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Author SHA1 Message Date
Kiryl Shutsemau
476849b0fb riscv/mm: align vmemmap to maximal folio size 
The upcoming change to the HugeTLB vmemmap optimization (HVO) requires
struct pages of the head page to be naturally aligned with regard to the
folio size.

Align vmemmap to the newly introduced MAX_FOLIO_VMEMMAP_ALIGN.

Link: https://lkml.kernel.org/r/20260227194302.274384-6-kas@kernel.org
Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Baoquan He <bhe@redhat.com>
Cc: Christoph Lameter <cl@gentwo.org>
Cc: David Hildenbrand (arm) <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-04-05 13:53:08 -07:00
Mike Rapoport (Microsoft)
6215d9f447 arch, mm: consolidate empty_zero_page 
Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of
ZERO_PAGE() to 4.

Every architecture defines empty_zero_page that way or another, but for the
most of them it is always a page aligned page in BSS and most definitions
of ZERO_PAGE do virt_to_page(empty_zero_page).

Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the
core MM and drop these definitions in architectures that do not implement
colored zero page (MIPS and s390).

ZERO_PAGE() remains a macro because turning it to a wrapper for a static
inline causes severe pain in header dependencies.

For the most part the change is mechanical, with these being noteworthy:

* alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot
  parameters. Switching to a generic empty_zero_page removes the aliasing
  and keeps ZERO_PGE for boot parameters only
* arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of
  ZERO_PAGE() is kept intact.
* m68k/parisc/um: allocated empty_zero_page from memblock,
  although they do not support zero page coloring and having it in BSS
  will work fine.
* sparc64 can have empty_zero_page in BSS rather allocate it, but it
  can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE()
  but instead of allocating it, make mem_map_zero point to
  empty_zero_page.
* sh: used empty_zero_page for boot parameters at the very early boot.
  Rename the parameters page to boot_params_page and let sh use the generic
  empty_zero_page.
* hexagon: had an amusing comment about empty_zero_page

	/* A handy thing to have if one has the RAM. Declared in head.S */

  that unfortunately had to go :)

Link: https://lkml.kernel.org/r/20260211103141.3215197-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>		[parisc]
Tested-by: Helge Deller <deller@gmx.de>		[parisc]
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>	[alpha]
Acked-by: Dinh Nguyen <dinguyen@kernel.org>	[nios2]
Acked-by: Andreas Larsson <andreas@gaisler.com>	[sparc]
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-04-05 13:53:01 -07:00
Linus Torvalds
cee73b1e84 Merge tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 
Pull RISC-V updates from Paul Walmsley:

 - Add support for control flow integrity for userspace processes.

   This is based on the standard RISC-V ISA extensions Zicfiss and
   Zicfilp

 - Improve ptrace behavior regarding vector registers, and add some
   selftests

 - Optimize our strlen() assembly

 - Enable the ISO-8859-1 code page as built-in, similar to ARM64, for
   EFI volume mounting

 - Clean up some code slightly, including defining copy_user_page() as
   copy_page() rather than memcpy(), aligning us with other
   architectures; and using max3() to slightly simplify an expression
   in riscv_iommu_init_check()

* tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits)
  riscv: lib: optimize strlen loop efficiency
  selftests: riscv: vstate_exec_nolibc: Use the regular prctl() function
  selftests: riscv: verify ptrace accepts valid vector csr values
  selftests: riscv: verify ptrace rejects invalid vector csr inputs
  selftests: riscv: verify syscalls discard vector context
  selftests: riscv: verify initial vector state with ptrace
  selftests: riscv: test ptrace vector interface
  riscv: ptrace: validate input vector csr registers
  riscv: csr: define vtype register elements
  riscv: vector: init vector context with proper vlenb
  riscv: ptrace: return ENODATA for inactive vector extension
  kselftest/riscv: add kselftest for user mode CFI
  riscv: add documentation for shadow stack
  riscv: add documentation for landing pad / indirect branch tracking
  riscv: create a Kconfig fragment for shadow stack and landing pad support
  arch/riscv: add dual vdso creation logic and select vdso based on hw
  arch/riscv: compile vdso with landing pad and shadow stack note
  riscv: enable kernel access to shadow stack memory via the FWFT SBI call
  riscv: add kernel command line option to opt out of user CFI
  riscv/hwprobe: add zicfilp / zicfiss enumeration in hwprobe
  ...
 2026-02-12 19:17:44 -08:00
Mike Rapoport (Microsoft)
9fac145b6d mm, arch: consolidate hugetlb CMA reservation 
Every architecture that supports hugetlb_cma command line parameter
reserves CMA areas for hugetlb during setup_arch().

This obfuscates the ordering of hugetlb CMA initialization with respect to
the rest initialization of the core MM.

Introduce arch_hugetlb_cma_order() callback to allow architectures report
the desired order-per-bit of CMA areas and provide a week implementation
of arch_hugetlb_cma_order() for architectures that don't support hugetlb
with CMA.

Use this callback in hugetlb_cma_reserve() instead if passing the order as
parameter and call hugetlb_cma_reserve() from mm_core_init_early() rather
than have it spread over architecture specific code.

Link: https://lkml.kernel.org/r/20260111082105.290734-28-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-26 20:02:19 -08:00
Mike Rapoport (Microsoft)
4267739cab arch, mm: consolidate initialization of SPARSE memory model 
Every architecture calls sparse_init() during setup_arch() although the
data structures created by sparse_init() are not used until the
initialization of the core MM.

Beside the code duplication, calling sparse_init() from architecture
specific code causes ordering differences of vmemmap and HVO
initialization on different architectures.

Move the call to sparse_init() from architecture specific code to
free_area_init() to ensure that vmemmap and HVO initialization order is
always the same.

Link: https://lkml.kernel.org/r/20260111082105.290734-25-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-26 20:02:18 -08:00
Mike Rapoport (Microsoft)
d49004c5f0 arch, mm: consolidate initialization of nodes, zones and memory map 
To initialize node, zone and memory map data structures every architecture
calls free_area_init() during setup_arch() and passes it an array of zone
limits.

Beside code duplication it creates "interesting" ordering cases between
allocation and initialization of hugetlb and the memory map.  Some
architectures allocate hugetlb pages very early in setup_arch() in certain
cases, some only create hugetlb CMA areas in setup_arch() and sometimes
hugetlb allocations happen mm_core_init().

With arch_zone_limits_init() helper available now on all architectures it
is no longer necessary to call free_area_init() from architecture setup
code.  Rather core MM initialization can call arch_zone_limits_init() in a
single place.

This allows to unify ordering of hugetlb vs memory map allocation and
initialization.

Remove the call to free_area_init() from architecture specific code and
place it in a new mm_core_init_early() function that is called immediately
after setup_arch().

After this refactoring it is possible to consolidate hugetlb allocations
and eliminate differences in ordering of hugetlb and memory map
initialization among different architectures.

As the first step of this consolidation move hugetlb_bootmem_alloc() to
mm_core_early_init().

Link: https://lkml.kernel.org/r/20260111082105.290734-24-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-26 20:02:18 -08:00
Mike Rapoport (Microsoft)
db8cdb0ad6 riscv: introduce arch_zone_limits_init() 
Move calculations of zone limits to a dedicated arch_zone_limits_init()
function.

Later MM core will use this function as an architecture specific callback
during nodes and zones initialization and thus there won't be a need to
call free_area_init() from every architecture.

Link: https://lkml.kernel.org/r/20260111082105.290734-17-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-26 20:02:16 -08:00
Deepak Gupta
6c7559f22b riscv/mm: ensure PROT_WRITE leads to VM_READ | VM_WRITE 
'arch_calc_vm_prot_bits' is implemented on risc-v to return VM_READ |
VM_WRITE if PROT_WRITE is specified. Similarly 'riscv_sys_mmap' is
updated to convert all incoming PROT_WRITE to (PROT_WRITE | PROT_READ).
This is to make sure that any existing apps using PROT_WRITE still work.

Earlier 'protection_map[VM_WRITE]' used to pick read-write PTE encodings.
Now 'protection_map[VM_WRITE]' will always pick PAGE_SHADOWSTACK PTE
encodings for shadow stack. The above changes ensure that existing apps
continue to work because underneath, the kernel will be picking
'protection_map[VM_WRITE|VM_READ]' PTE encodings.

Reviewed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6
Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com>
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-6-b55691eacf4f@rivosinc.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
 2026-01-25 21:09:53 -07:00
Vishal Moola (Oracle)
c9a7161044 riscv: Remove __GFP_HIGHMEM masking 
Remove unnecessary __GFP_HIGHMEM masking, which was introduced with
commit 380f2c1ae9 ("riscv: convert alloc_{pmd, pte}_late() to use
ptdescs"). GFP_KERNEL doesn't contain __GFP_HIGHMEM.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Link: https://patch.msgid.link/20251107182620.95844-1-vishal.moola@gmail.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
 2025-11-19 09:19:27 -07:00
Linus Torvalds
8804d970fa Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 
Pull MM updates from Andrew Morton:

 - "mm, swap: improve cluster scan strategy" from Kairui Song improves
   performance and reduces the failure rate of swap cluster allocation

 - "support large align and nid in Rust allocators" from Vitaly Wool
   permits Rust allocators to set NUMA node and large alignment when
   perforning slub and vmalloc reallocs

 - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
   DAMOS_STAT's handling of the DAMON operations sets for virtual
   address spaces for ops-level DAMOS filters

 - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
   Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps

 - "mm/mincore: minor clean up for swap cache checking" from Kairui Song
   performs some cleanup in the swap code

 - "mm: vm_normal_page*() improvements" from David Hildenbrand provides
   code cleanup in the pagemap code

 - "add persistent huge zero folio support" from Pankaj Raghav provides
   a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero

 - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
   the recently added Kexec Handover feature

 - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
   Stoakes turns mm_struct.flags into a bitmap. To end the constant
   struggle with space shortage on 32-bit conflicting with 64-bit's
   needs

 - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
   code

 - "selftests/mm: Fix false positives and skip unsupported tests" from
   Donet Tom fixes a few things in our selftests code

 - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
   from David Hildenbrand "allows individual processes to opt-out of
   THP=always into THP=madvise, without affecting other workloads on the
   system".

   It's a long story - the [1/N] changelog spells out the considerations

 - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
   the memdesc project. Please see

      https://kernelnewbies.org/MatthewWilcox/Memdescs and
      https://blogs.oracle.com/linux/post/introducing-memdesc

 - "Tiny optimization for large read operations" from Chi Zhiling
   improves the efficiency of the pagecache read path

 - "Better split_huge_page_test result check" from Zi Yan improves our
   folio splitting selftest code

 - "test that rmap behaves as expected" from Wei Yang adds some rmap
   selftests

 - "remove write_cache_pages()" from Christoph Hellwig removes that
   function and converts its two remaining callers

 - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
   selftests issues

 - "introduce kernel file mapped folios" from Boris Burkov introduces
   the concept of "kernel file pages". Using these permits btrfs to
   account its metadata pages to the root cgroup, rather than to the
   cgroups of random inappropriate tasks

 - "mm/pageblock: improve readability of some pageblock handling" from
   Wei Yang provides some readability improvements to the page allocator
   code

 - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
   to understand arm32 highmem

 - "tools: testing: Use existing atomic.h for vma/maple tests" from
   Brendan Jackman performs some code cleanups and deduplication under
   tools/testing/

 - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
   a couple of 32-bit issues in tools/testing/radix-tree.c

 - "kasan: unify kasan_enabled() and remove arch-specific
   implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
   initialization code into a common arch-neutral implementation

 - "mm: remove zpool" from Johannes Weiner removes zspool - an
   indirection layer which now only redirects to a single thing
   (zsmalloc)

 - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
   couple of cleanups in the fork code

 - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
   adjustments at various nth_page() callsites, eventually permitting
   the removal of that undesirable helper function

 - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
   creates a KASAN read-only mode for ARM, using that architecture's
   memory tagging feature. It is felt that a read-only mode KASAN is
   suitable for use in production systems rather than debug-only

 - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
   some tidying in the hugetlb folio allocation code

 - "mm: establish const-correctness for pointer parameters" from Max
   Kellermann makes quite a number of the MM API functions more accurate
   about the constness of their arguments. This was getting in the way
   of subsystems (in this case CEPH) when they attempt to improving
   their own const/non-const accuracy

 - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
   code sites which were confused over when to use free_pages() vs
   __free_pages()

 - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
   mapletree code accessible to Rust. Required by nouveau and by its
   forthcoming successor: the new Rust Nova driver

 - "selftests/mm: split_huge_page_test: split_pte_mapped_thp
   improvements" from David Hildenbrand adds a fix and some cleanups to
   the thp selftesting code

 - "mm, swap: introduce swap table as swap cache (phase I)" from Chris
   Li and Kairui Song is the first step along the path to implementing
   "swap tables" - a new approach to swap allocation and state tracking
   which is expected to yield speed and space improvements. This
   patchset itself yields a 5-20% performance benefit in some situations

 - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
   layer to clean up the ptdesc code a little

 - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
   issues in our 5-level pagetable selftesting code

 - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
   addresses a couple of minor issues in relatively new memory
   allocation profiling feature

 - "Small cleanups" from Matthew Wilcox has a few cleanups in
   preparation for more memdesc work

 - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
   Quanmin Yan makes some changes to DAMON in furtherance of supporting
   arm highmem

 - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
   Anjum adds that compiler check to selftests code and fixes the
   fallout, by removing dead code

 - "Improvements to Victim Process Thawing and OOM Reaper Traversal
   Order" from zhongjinji makes a number of improvements in the OOM
   killer: mainly thawing a more appropriate group of victim threads so
   they can release resources

 - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
   is a bunch of small and unrelated fixups for DAMON

 - "mm/damon: define and use DAMON initialization check function" from
   SeongJae Park implement reliability and maintainability improvements
   to a recently-added bug fix

 - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
   SeongJae Park provides additional transparency to userspace clients
   of the DAMON_STAT information

 - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
   some constraints on khubepaged's collapsing of anon VMAs. It also
   increases the success rate of MADV_COLLAPSE against an anon vma

 - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
   from Lorenzo Stoakes moves us further towards removal of
   file_operations.mmap(). This patchset concentrates upon clearing up
   the treatment of stacked filesystems

 - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
   provides some fixes and improvements to mlock's tracking of large
   folios. /proc/meminfo's "Mlocked" field became more accurate

 - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
   Donet Tom fixes several user-visible KSM stats inaccuracies across
   forks and adds selftest code to verify these counters

 - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
   some potential but presently benign issues in KSM's mm_slot handling

* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
  mm: swap: check for stable address space before operating on the VMA
  mm: convert folio_page() back to a macro
  mm/khugepaged: use start_addr/addr for improved readability
  hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
  alloc_tag: fix boot failure due to NULL pointer dereference
  mm: silence data-race in update_hiwater_rss
  mm/memory-failure: don't select MEMORY_ISOLATION
  mm/khugepaged: remove definition of struct khugepaged_mm_slot
  mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
  hugetlb: increase number of reserving hugepages via cmdline
  selftests/mm: add fork inheritance test for ksm_merging_pages counter
  mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
  drivers/base/node: fix double free in register_one_node()
  mm: remove PMD alignment constraint in execmem_vmalloc()
  mm/memory_hotplug: fix typo 'esecially' -> 'especially'
  mm/rmap: improve mlock tracking for large folios
  mm/filemap: map entire large folio faultaround
  mm/fault: try to map the entire file folio in finish_fault()
  mm/rmap: mlock large folios in try_to_unmap_one()
  mm/rmap: fix a mlock race condition in folio_referenced_one()
  ...
 2025-10-02 18:18:33 -07:00
Vishal Moola (Oracle)
5e8fce2016 riscv: stop calling page_address() in free_pages() 
free_pages() should be used when we only have a virtual address.  We
should call __free_pages() directly on our page instead.

Link: https://lkml.kernel.org/r/20250903185921.1785167-5-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Justin Sanders <justin@coraid.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-21 14:22:17 -07:00
Djordje Todorovic
0b0ca959d2 riscv: errata: Fix the PAUSE Opcode for MIPS P8700 
Add ERRATA_MIPS and ERRATA_MIPS_P8700_PAUSE_OPCODE configs.
Handle errata for the MIPS PAUSE instruction.

Signed-off-by: Djordje Todorovic <djordje.todorovic@htecgroup.com>
Signed-off-by: Aleksandar Rikalo <arikalo@gmail.com>
Signed-off-by: Raj Vishwanathan4 <rvishwanathan@mips.com>
Signed-off-by: Aleksa Paunovic <aleksa.paunovic@htecgroup.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250724-p8700-pause-v5-7-a6cbbe1c3412@htecgroup.com
[pjw@kernel.org: updated to apply and compile; fixed a checkpatch issue]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
 2025-09-19 10:33:56 -06:00
Junhui Liu
17e9521044 riscv: mm: Use mmu-type from FDT to limit SATP mode 
Some RISC-V implementations may hang when attempting to write an
unsupported SATP mode, even though the latest RISC-V specification
states such writes should have no effect. To avoid this issue, the
logic for selecting SATP mode has been refined:

The kernel now determines the SATP mode limit by taking the minimum of
the value specified by the kernel command line (noXlvl) and the
"mmu-type" property in the device tree (FDT). If only one is specified,
use that.
- If the resulting limit is sv48 or higher, the kernel will probe SATP
  modes from this limit downward until a supported mode is found.
- If the limit is sv39, the kernel will directly use sv39 without
  probing.

This ensures SATP mode selection is safe and compatible with both
hardware and user configuration, minimizing the risk of hangs.

Signed-off-by: Junhui Liu <junhui.liu@pigmoral.tech>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Nutty Liu <liujingqi@lanxincomputing.com>
Link: https://lore.kernel.org/r/20250722-satp-from-fdt-v1-2-5ba22218fa5f@pigmoral.tech
Signed-off-by: Paul Walmsley <pjw@kernel.org>
 2025-09-18 08:18:14 -06:00
Junhui Liu
f3243bed39 riscv: mm: Return intended SATP mode for noXlvl options 
Change the return value of match_noXlvl() to return the SATP mode that
will be used, rather than the mode being disabled. This enables unified
logic for return value judgement with the function that obtains mmu-type
from the fdt, avoiding extra conversion. This only changes the naming,
with no functional impact.

Signed-off-by: Junhui Liu <junhui.liu@pigmoral.tech>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Nutty Liu <liujingqi@lanxincomputing.com>
Link: https://lore.kernel.org/r/20250722-satp-from-fdt-v1-1-5ba22218fa5f@pigmoral.tech
Signed-off-by: Paul Walmsley <pjw@kernel.org>
 2025-09-17 17:00:59 -06:00
Jiri Bohac
35c18f2933 Add a new optional ",cma" suffix to the crashkernel= command line option 
Patch series "kdump: crashkernel reservation from CMA", v5.

This series implements a way to reserve additional crash kernel memory
using CMA.

Currently, all the memory for the crash kernel is not usable by the 1st
(production) kernel.  It is also unmapped so that it can't be corrupted by
the fault that will eventually trigger the crash.  This makes sense for
the memory actually used by the kexec-loaded crash kernel image and initrd
and the data prepared during the load (vmcoreinfo, ...).  However, the
reserved space needs to be much larger than that to provide enough
run-time memory for the crash kernel and the kdump userspace.  Estimating
the amount of memory to reserve is difficult.  Being too careful makes
kdump likely to end in OOM, being too generous takes even more memory from
the production system.  Also, the reservation only allows reserving a
single contiguous block (or two with the "low" suffix).  I've seen systems
where this fails because the physical memory is fragmented.

By reserving additional crashkernel memory from CMA, the main crashkernel
reservation can be just large enough to fit the kernel and initrd image,
minimizing the memory taken away from the production system.  Most of the
run-time memory for the crash kernel will be memory previously available
to userspace in the production system.  As this memory is no longer
wasted, the reservation can be done with a generous margin, making kdump
more reliable.  Kernel memory that we need to preserve for dumping is
normally not allocated from CMA, unless it is explicitly allocated as
movable.  Currently this is only the case for memory ballooning and zswap.
Such movable memory will be missing from the vmcore.  User data is
typically not dumped by makedumpfile.  When dumping of user data is
intended this new CMA reservation cannot be used.

There are five patches in this series:

The first adds a new ",cma" suffix to the recenly introduced generic
crashkernel parsing code.  parse_crashkernel() takes one more argument to
store the cma reservation size.

The second patch implements reserve_crashkernel_cma() which performs the
reservation.  If the requested size is not available in a single range,
multiple smaller ranges will be reserved.

The third patch updates Documentation/, explicitly mentioning the
potential DMA corruption of the CMA-reserved memory.

The fourth patch adds a short delay before booting the kdump kernel,
allowing pending DMA transfers to finish.

The fifth patch enables the functionality for x86 as a proof of
concept. There are just three things every arch needs to do:
- call reserve_crashkernel_cma()
- include the CMA-reserved ranges in the physical memory map
- exclude the CMA-reserved ranges from the memory available
  through /proc/vmcore by excluding them from the vmcoreinfo
  PT_LOAD ranges.

Adding other architectures is easy and I can do that as soon as this
series is merged.

With this series applied, specifying
	crashkernel=100M craskhernel=1G,cma
on the command line will make a standard crashkernel reservation
of 100M, where kexec will load the kernel and initrd.

An additional 1G will be reserved from CMA, still usable by the production
system.  The crash kernel will have 1.1G memory available.  The 100M can
be reliably predicted based on the size of the kernel and initrd.

The new cma suffix is completely optional. When no
crashkernel=size,cma is specified, everything works as before.


This patch (of 5):

Add a new cma_size parameter to parse_crashkernel().  When not NULL, call
__parse_crashkernel to parse the CMA reservation size from
"crashkernel=size,cma" and store it in cma_size.

Set cma_size to NULL in all calls to parse_crashkernel().

Link: https://lkml.kernel.org/r/aEqnxxfLZMllMC8I@dwarf.suse.cz
Link: https://lkml.kernel.org/r/aEqoQckgoTQNULnh@dwarf.suse.cz
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Donald Dutile <ddutile@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Philipp Rudo <prudo@redhat.com>
Cc: Pingfan Liu <piliu@redhat.com>
Cc: Tao Liu <ltao@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-19 19:08:22 -07:00
Kevin Brodsky
8472cc4503 riscv: mm: call PUD/P4D ctor in special kernel pgtable alloc 
Constructors for PUD/P4D-level pgtables were recently introduced.  They
should be called for all pgtables; make sure they are called for special
kernel mappings created by create_pgd_mapping() too.

While at it also switch to using pagetable_alloc() like in
alloc_{pte,pmd}_late().

Link: https://lkml.kernel.org/r/20250408095222.860601-13-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Waleij <linus.walleij@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: <x86@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-05-11 17:48:23 -07:00
Kevin Brodsky
0e3a16a760 riscv: mm: clarify ctor mm argument in alloc_{pte,pmd}_late 
pagetable_{pte,pmd}_ctor(mm, ptdesc) skip the ptlock initialisation if mm
is &init_mm.  To avoid unnecessary overhead, it is therefore preferable to
pass the actual mm associated to the PTE/PMD.

Unfortunately, this proves challenging for alloc_{pte,pmd}_late() as the
associated mm is not available at the point where they are called - in
fact not even top-level functions like create_pgd_mapping() are passed the
mm.  As a result they both call the ctor with NULL as mm; this is safe but
potentially wasteful.

This is not a new situation, but let's add a couple of comments to clarify
it.

Link: https://lkml.kernel.org/r/20250408095222.860601-11-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Waleij <linus.walleij@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: <x86@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-05-11 17:48:23 -07:00
Kevin Brodsky
d82d3bf411 mm: pass mm down to pagetable_{pte,pmd}_ctor 
Patch series "Always call constructor for kernel page tables", v2.

There has been much confusion around exactly when page table
constructors/destructors (pagetable_*_[cd]tor) are supposed to be called. 
They were initially introduced for user PTEs only (to support split page
table locks), then at the PMD level for the same purpose.  Accounting was
added later on, starting at the PTE level and then moving to higher levels
(PMD, PUD).  Finally, with my earlier series "Account page tables at all
levels" [1], the ctor/dtor is run for all levels, all the way to PGD.

I thought this was the end of the story, and it hopefully is for user
pgtables, but I was wrong for what concerns kernel pgtables.  The current
situation there makes very little sense:

* At the PTE level, the ctor/dtor is not called (at least in the generic
  implementation).  Specific helpers are used for kernel pgtables at this
  level (pte_{alloc,free}_kernel()) and those have never called the
  ctor/dtor, most likely because they were initially irrelevant in the
  kernel case.

* At all other levels, the ctor/dtor is normally called.  This is
  potentially wasteful at the PMD level (more on that later).

This series aims to ensure that the ctor/dtor is always called for kernel
pgtables, as it already is for user pgtables.  Besides consistency, the
main motivation is to guarantee that ctor/dtor hooks are systematically
called; this makes it possible to insert hooks to protect page tables [2],
for instance.  There is however an extra challenge: split locks are not
used for kernel pgtables, and it would therefore be wasteful to initialise
them (ptlock_init()).

It is worth clarifying exactly when split locks are used.  They clearly
are for user pgtables, but as illustrated in commit 61444cde91 ("ARM:
8591/1: mm: use fully constructed struct pages for EFI pgd allocations"),
they also are for special page tables like efi_mm.  The one case where
split locks are definitely unused is pgtables owned by init_mm; this is
consistent with the behaviour of apply_to_pte_range().

The approach chosen in this series is therefore to pass the mm associated
to the pgtables being constructed to pagetable_{pte,pmd}_ctor() (patch 1),
and skip ptlock_init() if mm == &init_mm (patch 3 and 7).  This makes it
possible to call the PTE ctor/dtor from pte_{alloc,free}_kernel() without
unintended consequences (patch 3).  As a result the accounting functions
are now called at all levels for kernel pgtables, and split locks are
never initialised.

In configurations where ptlocks are dynamically allocated (32-bit,
PREEMPT_RT, etc.) and ARCH_ENABLE_SPLIT_PMD_PTLOCK is selected, this
series results in the removal of a kmem_cache allocation for every kernel
PMD.  Additionally, for certain architectures that do not use
<asm-generic/pgalloc.h> such as s390, the same optimisation occurs at the
PTE level.

===

Things get more complicated when it comes to special pgtable allocators
(patch 8-12).  All architectures need such allocators to create initial
kernel pgtables; we are not concerned with those as the ctor cannot be
called so early in the boot sequence.  However, those allocators may also
be used later in the boot sequence or during normal operations.  There are
two main use-cases:

1. Mapping EFI memory: efi_mm (arm, arm64, riscv)
2. arch_add_memory(): init_mm

The ctor is already explicitly run (at the PTE/PMD level) in the first
case, as required for pgtables that are not associated with init_mm. 
However the same allocators may also be used for the second use-case (or
others), and this is where it gets messy.  Patch 1 calls the ctor with
NULL as mm in those situations, as the actual mm isn't available. 
Practically this means that ptlocks will be unconditionally initialised. 
This is fine on arm - create_mapping_late() is only used for the EFI
mapping.  On arm64, __create_pgd_mapping() is also used by
arch_add_memory(); patch 8/9/11 ensure that ctors are called at all levels
with the appropriate mm.  The situation is similar on riscv, but
propagating the mm down to the ctor would require significant refactoring.
Since they are already called unconditionally, this series leaves riscv
no worse off - patch 10 adds comments to clarify the situation.

From a cursory look at other architectures implementing arch_add_memory(),
s390 and x86 may also need a similar treatment to add constructor calls. 
This is to be taken care of in a future version or as a follow-up.

===

The complications in those special pgtable allocators beg the question:
does it really make sense to treat efi_mm and init_mm differently in e.g. 
apply_to_pte_range()?  Maybe what we really need is a way to tell if an mm
corresponds to user memory or not, and never use split locks for non-user
mm's.  Feedback and suggestions welcome!


This patch (of 12):

In preparation for calling constructors for all kernel page tables while
eliding unnecessary ptlock initialisation, let's pass down the associated
mm to the PTE/PMD level ctors.  (These are the two levels where ptlocks
are used.)

In most cases the mm is already around at the point of calling the ctor so
we simply pass it down.  This is however not the case for special page
table allocators:

* arch/arm/mm/mmu.c
* arch/arm64/mm/mmu.c
* arch/riscv/mm/init.c

In those cases, the page tables being allocated are either for standard
kernel memory (init_mm) or special page directories, which may not be
associated to any mm.  For now let's pass NULL as mm; this will be refined
where possible in future patches.

No functional change in this patch.

Link: https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ [1]
Link: https://lore.kernel.org/linux-hardening/20250203101839.1223008-1-kevin.brodsky@arm.com/ [2]
Link: https://lkml.kernel.org/r/20250408095222.860601-1-kevin.brodsky@arm.com
Link: https://lkml.kernel.org/r/20250408095222.860601-2-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>	[s390]
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Linus Waleij <linus.walleij@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: <x86@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-05-11 17:48:21 -07:00
Linus Torvalds
4a1d8ababd Merge tag 'riscv-for-linus-6.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 
Pull RISC-V updates from Palmer Dabbelt:

 - The sub-architecture selection Kconfig system has been cleaned up,
   the documentation has been improved, and various detections have been
   fixed

 - The vector-related extensions dependencies are now validated when
   parsing from device tree and in the DT bindings

 - Misaligned access probing can be overridden via a kernel command-line
   parameter, along with various fixes to misalign access handling

 - Support for relocatable !MMU kernels builds

 - Support for hpge pfnmaps, which should improve TLB utilization

 - Support for runtime constants, which improves the d_hash()
   performance

 - Support for bfloat16, Zicbom, Zaamo, Zalrsc, Zicntr, Zihpm

 - Various fixes, including:
      - We were missing a secondary mmu notifier call when flushing the
        tlb which is required for IOMMU
      - Fix ftrace panics by saving the registers as expected by ftrace
      - Fix a couple of stimecmp usage related to cpu hotplug
      - purgatory_start is now aligned as per the STVEC requirements
      - A fix for hugetlb when calculating the size of non-present PTEs

* tag 'riscv-for-linus-6.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (65 commits)
  riscv: Add norvc after .option arch in runtime const
  riscv: Make sure toolchain supports zba before using zba instructions
  riscv/purgatory: 4B align purgatory_start
  riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator
  selftests: riscv: fix v_exec_initval_nolibc.c
  riscv: Fix hugetlb retrieval of number of ptes in case of !present pte
  riscv: print hartid on bringup
  riscv: Add norvc after .option arch in runtime const
  riscv: Remove CONFIG_PAGE_OFFSET
  riscv: Support CONFIG_RELOCATABLE on riscv32
  asm-generic: Always define Elf_Rel and Elf_Rela
  riscv: Support CONFIG_RELOCATABLE on NOMMU
  riscv: Allow NOMMU kernels to access all of RAM
  riscv: Remove duplicate CONFIG_PAGE_OFFSET definition
  RISC-V: errata: Use medany for relocatable builds
  dt-bindings: riscv: document vector crypto requirements
  dt-bindings: riscv: add vector sub-extension dependencies
  dt-bindings: riscv: d requires f
  RISC-V: add f & d extension validation checks
  RISC-V: add vector crypto extension validation checks
  ...
 2025-04-04 09:49:17 -07:00
Linus Torvalds
d6b02199cd Merge tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 
Pull non-MM updates from Andrew Morton:

 - The series "powerpc/crash: use generic crashkernel reservation" from
   Sourabh Jain changes powerpc's kexec code to use more of the generic
   layers.

 - The series "get_maintainer: report subsystem status separately" from
   Vlastimil Babka makes some long-requested improvements to the
   get_maintainer output.

 - The series "ucount: Simplify refcounting with rcuref_t" from
   Sebastian Siewior cleans up and optimizing the refcounting in the
   ucount code.

 - The series "reboot: support runtime configuration of emergency
   hw_protection action" from Ahmad Fatoum improves the ability for a
   driver to perform an emergency system shutdown or reboot.

 - The series "Converge on using secs_to_jiffies() part two" from Easwar
   Hariharan performs further migrations from msecs_to_jiffies() to
   secs_to_jiffies().

 - The series "lib/interval_tree: add some test cases and cleanup" from
   Wei Yang permits more userspace testing of kernel library code, adds
   some more tests and performs some cleanups.

 - The series "hung_task: Dump the blocking task stacktrace" from Masami
   Hiramatsu arranges for the hung_task detector to dump the stack of
   the blocking task and not just that of the blocked task.

 - The series "resource: Split and use DEFINE_RES*() macros" from Andy
   Shevchenko provides some cleanups to the resource definition macros.

 - Plus the usual shower of singleton patches - please see the
   individual changelogs for details.

* tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  mailmap: consolidate email addresses of Alexander Sverdlin
  fs/procfs: fix the comment above proc_pid_wchan()
  relay: use kasprintf() instead of fixed buffer formatting
  resource: replace open coded variant of DEFINE_RES()
  resource: replace open coded variants of DEFINE_RES_*_NAMED()
  resource: replace open coded variant of DEFINE_RES_NAMED_DESC()
  resource: split DEFINE_RES_NAMED_DESC() out of DEFINE_RES_NAMED()
  samples: add hung_task detector mutex blocking sample
  hung_task: show the blocker task if the task is hung on mutex
  kexec_core: accept unaccepted kexec segments' destination addresses
  watchdog/perf: optimize bytes copied and remove manual NUL-termination
  lib/interval_tree: fix the comment of interval_tree_span_iter_next_gap()
  lib/interval_tree: skip the check before go to the right subtree
  lib/interval_tree: add test case for span iteration
  lib/interval_tree: add test case for interval_tree_iter_xxx() helpers
  lib/rbtree: add random seed
  lib/rbtree: split tests
  lib/rbtree: enable userland test suite for rbtree related data structure
  checkpatch: describe --min-conf-desc-length
  scripts/gdb/symbols: determine KASLR offset on s390
  ...
 2025-04-01 10:06:52 -07:00
Samuel Holland
e1cf2d009b riscv: Remove CONFIG_PAGE_OFFSET 
The current definition of CONFIG_PAGE_OFFSET is problematic for a couple
of reasons:
 1) The value is misleading for normal 64-bit kernels, where it is
    overridden at runtime if Sv48 or Sv39 is chosen. This is especially
    the case for XIP kernels, which always use Sv39.
 2) The option is not user-visible, but for NOMMU kernels it must be a
    valid RAM address, and for !RELOCATABLE it must additionally be the
    exact address where the kernel is loaded.

Fix both of these by removing the option.
 1) For MMU kernels, drop the indirection through Kconfig. Additionally,
    for XIP, drop the indirection through kernel_map.
 2) For NOMMU kernels, use the user-visible physical RAM base if
    provided. Otherwise, force the kernel to be relocatable.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Jesse Taube <mr.bossman075@gmail.com>
Link: https://lore.kernel.org/r/20241026171441.3047904-7-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2025-03-26 15:56:46 -07:00
Samuel Holland
ea2bde36a4 riscv: Support CONFIG_RELOCATABLE on riscv32 
When adjusted to use the correctly-sized ELF types, relocate_kernel()
works on riscv32 as well. The caveat about crossing an intermediate page
table boundary does not apply to riscv32, since for Sv32 the early
kernel mapping uses only PGD entries. Since KASLR is not yet supported
on riscv32, this option is mostly useful for NOMMU.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20241026171441.3047904-6-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2025-03-26 15:56:45 -07:00
Samuel Holland
51b766c79a riscv: Support CONFIG_RELOCATABLE on NOMMU 
Move relocate_kernel() out of the CONFIG_MMU block so it can be called
from the NOMMU version of setup_vm(). Set some offsets in kernel_map so
relocate_kernel() does not need to be modified. Relocatable NOMMU
kernels can be loaded to any physical memory address; they no longer
depend on CONFIG_PAGE_OFFSET.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20241026171441.3047904-4-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2025-03-26 15:56:41 -07:00
Mike Rapoport (Microsoft)
8afa901c14 arch, mm: make releasing of memory to page allocator more explicit 
The point where the memory is released from memblock to the buddy
allocator is hidden inside arch-specific mem_init()s and the call to
memblock_free_all() is needlessly duplicated in every artiste cure and
after introduction of arch_mm_preinit() hook, mem_init() implementation on
many architecture only contains the call to memblock_free_all().

Pull memblock_free_all() call into mm_core_init() and drop mem_init() on
relevant architectures to make it more explicit where the free memory is
released from memblock to the buddy allocator and to reduce code
duplication in architecture specific code.

Link: https://lkml.kernel.org/r/20250313135003.836600-14-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>	[x86]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Guo Ren (csky) <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-03-17 22:06:53 -07:00
Mike Rapoport (Microsoft)
0d98484ee3 arch, mm: introduce arch_mm_preinit 
Currently, implementation of mem_init() in every architecture consists of
one or more of the following:

* initializations that must run before page allocator is active, for
  instance swiotlb_init()
* a call to memblock_free_all() to release all the memory to the buddy
  allocator
* initializations that must run after page allocator is ready and there is
  no arch-specific hook other than mem_init() for that, like for example
  register_page_bootmem_info() in x86 and sparc64 or simple setting of
  mem_init_done = 1 in several architectures
* a bunch of semi-related stuff that apparently had no better place to
  live, for example a ton of BUILD_BUG_ON()s in parisc.

Introduce arch_mm_preinit() that will be the first thing called from
mm_core_init(). On architectures that have initializations that must happen
before the page allocator is ready, move those into arch_mm_preinit() along
with the code that does not depend on ordering with page allocator setup.

On several architectures this results in reduction of mem_init() to a
single call to memblock_free_all() that allows its consolidation next.

Link: https://lkml.kernel.org/r/20250313135003.836600-13-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>	[x86]
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Guo Ren (csky) <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-03-17 22:06:53 -07:00
Mike Rapoport (Microsoft)
e120d1bc12 arch, mm: set high_memory in free_area_init() 
high_memory defines upper bound on the directly mapped memory.  This bound
is defined by the beginning of ZONE_HIGHMEM when a system has high memory
and by the end of memory otherwise.

All this is known to generic memory management initialization code that
can set high_memory while initializing core mm structures.

Add a generic calculation of high_memory to free_area_init() and remove
per-architecture calculation except for the architectures that set and use
high_memory earlier than that.

Link: https://lkml.kernel.org/r/20250313135003.836600-11-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>	[x86]
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Guo Ren (csky) <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-03-17 22:06:52 -07:00
Mike Rapoport (Microsoft)
8268af309d arch, mm: set max_mapnr when allocating memory map for FLATMEM 
max_mapnr is essentially the size of the memory map for systems that use
FLATMEM. There is no reason to calculate it in each and every architecture
when it's anyway calculated in alloc_node_mem_map().

Drop setting of max_mapnr from architecture code and set it once in
alloc_node_mem_map().

While on it, move definition of mem_map and max_mapnr to mm/mm_init.c so
there won't be two copies for MMU and !MMU variants.

Link: https://lkml.kernel.org/r/20250313135003.836600-10-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>	[x86]
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Guo Ren (csky) <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-03-17 22:06:52 -07:00
Sourabh Jain
7b54a96f30 crash: remove an unused argument from reserve_crashkernel_generic() 
cmdline argument is not used in reserve_crashkernel_generic() so remove
it.  Correspondingly, all the callers have been updated as well.

No functional change intended.

Link: https://lkml.kernel.org/r/20250131113830.925179-3-sourabhjain@linux.ibm.com
Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-03-16 22:30:47 -07:00
Linus Torvalds
1b5f3c51fb Merge tag 'riscv-for-linus-6.14-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 
Pull RISC-V updates from Palmer Dabbelt:

 - The PH1520 pinctrl and dwmac drivers are enabeled in defconfig

 - A redundant AQRL barrier has been removed from the futex cmpxchg
   implementation

 - Support for the T-Head vector extensions, which includes exposing
   these extensions to userspace on systems that implement them

 - Some more page table information is now printed on die() and systems
   that cause PA overflows

* tag 'riscv-for-linus-6.14-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: add a warning when physical memory address overflows
  riscv/mm/fault: add show_pte() before die()
  riscv: Add ghostwrite vulnerability
  selftests: riscv: Support xtheadvector in vector tests
  selftests: riscv: Fix vector tests
  riscv: hwprobe: Document thead vendor extensions and xtheadvector extension
  riscv: hwprobe: Add thead vendor extension probing
  riscv: vector: Support xtheadvector save/restore
  riscv: Add xtheadvector instruction definitions
  riscv: csr: Add CSR encodings for CSR_VXRM/CSR_VXSAT
  RISC-V: define the elements of the VCSR vector CSR
  riscv: vector: Use vlenb from DT for thead
  riscv: Add thead and xtheadvector as a vendor extension
  riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree
  dt-bindings: cpus: add a thead vlen register length property
  dt-bindings: riscv: Add xtheadvector ISA extension description
  RISC-V: Mark riscv_v_init() as __init
  riscv: defconfig: drop RT_GROUP_SCHED=y
  riscv/futex: Optimize atomic cmpxchg
  riscv: defconfig: enable pinctrl and dwmac support for TH1520
 2025-01-31 15:13:25 -08:00
Yunhui Cui
101971298b riscv: add a warning when physical memory address overflows 
The part of physical memory that exceeds the size of the linear mapping
will be discarded. When the system starts up normally, a warning message
will be printed to prevent confusion caused by the mismatch between the
system memory and the actual physical memory.

Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240814062625.19794-1-cuiyunhui@bytedance.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2025-01-29 18:36:09 -08:00
Linus Torvalds
9c5968db9e Merge tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 
Pull MM updates from Andrew Morton:
 "The various patchsets are summarized below. Plus of course many
  indivudual patches which are described in their changelogs.

   - "Allocate and free frozen pages" from Matthew Wilcox reorganizes
     the page allocator so we end up with the ability to allocate and
     free zero-refcount pages. So that callers (ie, slab) can avoid a
     refcount inc & dec

   - "Support large folios for tmpfs" from Baolin Wang teaches tmpfs to
     use large folios other than PMD-sized ones

   - "Fix mm/rodata_test" from Petr Tesarik performs some maintenance
     and fixes for this small built-in kernel selftest

   - "mas_anode_descend() related cleanup" from Wei Yang tidies up part
     of the mapletree code

   - "mm: fix format issues and param types" from Keren Sun implements a
     few minor code cleanups

   - "simplify split calculation" from Wei Yang provides a few fixes and
     a test for the mapletree code

   - "mm/vma: make more mmap logic userland testable" from Lorenzo
     Stoakes continues the work of moving vma-related code into the
     (relatively) new mm/vma.c

   - "mm/page_alloc: gfp flags cleanups for alloc_contig_*()" from David
     Hildenbrand cleans up and rationalizes handling of gfp flags in the
     page allocator

   - "readahead: Reintroduce fix for improper RA window sizing" from Jan
     Kara is a second attempt at fixing a readahead window sizing issue.
     It should reduce the amount of unnecessary reading

   - "synchronously scan and reclaim empty user PTE pages" from Qi Zheng
     addresses an issue where "huge" amounts of pte pagetables are
     accumulated:

       https://lore.kernel.org/lkml/cover.1718267194.git.zhengqi.arch@bytedance.com/

     Qi's series addresses this windup by synchronously freeing PTE
     memory within the context of madvise(MADV_DONTNEED)

   - "selftest/mm: Remove warnings found by adding compiler flags" from
     Muhammad Usama Anjum fixes some build warnings in the selftests
     code when optional compiler warnings are enabled

   - "mm: don't use __GFP_HARDWALL when migrating remote pages" from
     David Hildenbrand tightens the allocator's observance of
     __GFP_HARDWALL

   - "pkeys kselftests improvements" from Kevin Brodsky implements
     various fixes and cleanups in the MM selftests code, mainly
     pertaining to the pkeys tests

   - "mm/damon: add sample modules" from SeongJae Park enhances DAMON to
     estimate application working set size

   - "memcg/hugetlb: Rework memcg hugetlb charging" from Joshua Hahn
     provides some cleanups to memcg's hugetlb charging logic

   - "mm/swap_cgroup: remove global swap cgroup lock" from Kairui Song
     removes the global swap cgroup lock. A speedup of 10% for a
     tmpfs-based kernel build was demonstrated

   - "zram: split page type read/write handling" from Sergey Senozhatsky
     has several fixes and cleaups for zram in the area of
     zram_write_page(). A watchdog softlockup warning was eliminated

   - "move pagetable_*_dtor() to __tlb_remove_table()" from Kevin
     Brodsky cleans up the pagetable destructor implementations. A rare
     use-after-free race is fixed

   - "mm/debug: introduce and use VM_WARN_ON_VMG()" from Lorenzo Stoakes
     simplifies and cleans up the debugging code in the VMA merging
     logic

   - "Account page tables at all levels" from Kevin Brodsky cleans up
     and regularizes the pagetable ctor/dtor handling. This results in
     improvements in accounting accuracy

   - "mm/damon: replace most damon_callback usages in sysfs with new
     core functions" from SeongJae Park cleans up and generalizes
     DAMON's sysfs file interface logic

   - "mm/damon: enable page level properties based monitoring" from
     SeongJae Park increases the amount of information which is
     presented in response to DAMOS actions

   - "mm/damon: remove DAMON debugfs interface" from SeongJae Park
     removes DAMON's long-deprecated debugfs interfaces. Thus the
     migration to sysfs is completed

   - "mm/hugetlb: Refactor hugetlb allocation resv accounting" from
     Peter Xu cleans up and generalizes the hugetlb reservation
     accounting

   - "mm: alloc_pages_bulk: small API refactor" from Luiz Capitulino
     removes a never-used feature of the alloc_pages_bulk() interface

   - "mm/damon: extend DAMOS filters for inclusion" from SeongJae Park
     extends DAMOS filters to support not only exclusion (rejecting),
     but also inclusion (allowing) behavior

   - "Add zpdesc memory descriptor for zswap.zpool" from Alex Shi
     introduces a new memory descriptor for zswap.zpool that currently
     overlaps with struct page for now. This is part of the effort to
     reduce the size of struct page and to enable dynamic allocation of
     memory descriptors

   - "mm, swap: rework of swap allocator locks" from Kairui Song redoes
     and simplifies the swap allocator locking. A speedup of 400% was
     demonstrated for one workload. As was a 35% reduction for kernel
     build time with swap-on-zram

   - "mm: update mips to use do_mmap(), make mmap_region() internal"
     from Lorenzo Stoakes reworks MIPS's use of mmap_region() so that
     mmap_region() can be made MM-internal

   - "mm/mglru: performance optimizations" from Yu Zhao fixes a few
     MGLRU regressions and otherwise improves MGLRU performance

   - "Docs/mm/damon: add tuning guide and misc updates" from SeongJae
     Park updates DAMON documentation

   - "Cleanup for memfd_create()" from Isaac Manjarres does that thing

   - "mm: hugetlb+THP folio and migration cleanups" from David
     Hildenbrand provides various cleanups in the areas of hugetlb
     folios, THP folios and migration

   - "Uncached buffered IO" from Jens Axboe implements the new
     RWF_DONTCACHE flag which provides synchronous dropbehind for
     pagecache reading and writing. To permite userspace to address
     issues with massive buildup of useless pagecache when
     reading/writing fast devices

   - "selftests/mm: virtual_address_range: Reduce memory" from Thomas
     Weißschuh fixes and optimizes some of the MM selftests"

* tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  mm/compaction: fix UBSAN shift-out-of-bounds warning
  s390/mm: add missing ctor/dtor on page table upgrade
  kasan: sw_tags: use str_on_off() helper in kasan_init_sw_tags()
  tools: add VM_WARN_ON_VMG definition
  mm/damon/core: use str_high_low() helper in damos_wmark_wait_us()
  seqlock: add missing parameter documentation for raw_seqcount_try_begin()
  mm/page-writeback: consolidate wb_thresh bumping logic into __wb_calc_thresh
  mm/page_alloc: remove the incorrect and misleading comment
  zram: remove zcomp_stream_put() from write_incompressible_page()
  mm: separate move/undo parts from migrate_pages_batch()
  mm/kfence: use str_write_read() helper in get_access_type()
  selftests/mm/mkdirty: fix memory leak in test_uffdio_copy()
  kasan: hw_tags: Use str_on_off() helper in kasan_init_hw_tags()
  selftests/mm: virtual_address_range: avoid reading from VM_IO mappings
  selftests/mm: vm_util: split up /proc/self/smaps parsing
  selftests/mm: virtual_address_range: unmap chunks after validation
  selftests/mm: virtual_address_range: mmap() without PROT_WRITE
  selftests/memfd/memfd_test: fix possible NULL pointer dereference
  mm: add FGP_DONTCACHE folio creation flag
  mm: call filemap_fdatawrite_range_kick() after IOCB_DONTCACHE issue
  ...
 2025-01-26 18:36:23 -08:00
Qi Zheng
db6b435d73 mm: pgtable: introduce pagetable_dtor() 
The pagetable_p*_dtor() are exactly the same except for the handling of
ptlock.  If we make ptlock_free() handle the case where ptdesc->ptl is
NULL and remove VM_BUG_ON_PAGE() from pmd_ptlock_free(), we can unify
pagetable_p*_dtor() into one function.  Let's introduce pagetable_dtor()
to do this.

Later, pagetable_dtor() will be moved to tlb_remove_ptdesc(), so that
ptlock and page table pages can be freed together (regardless of whether
RCU is used).  This prevents the use-after-free problem where the ptlock
is freed immediately but the page table pages is freed later via RCU.

Link: https://lkml.kernel.org/r/47f44fff9dc68d9d9e9a0d6c036df275f820598a.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>	[s390]
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-01-25 20:22:22 -08:00
Xu Lu
f754f27e98 riscv: mm: Fix the out of bound issue of vmemmap address 
In sparse vmemmap model, the virtual address of vmemmap is calculated as:
((struct page *)VMEMMAP_START - (phys_ram_base >> PAGE_SHIFT)).
And the struct page's va can be calculated with an offset:
(vmemmap + (pfn)).

However, when initializing struct pages, kernel actually starts from the
first page from the same section that phys_ram_base belongs to. If the
first page's physical address is not (phys_ram_base >> PAGE_SHIFT), then
we get an va below VMEMMAP_START when calculating va for it's struct page.

For example, if phys_ram_base starts from 0x82000000 with pfn 0x82000, the
first page in the same section is actually pfn 0x80000. During
init_unavailable_range(), we will initialize struct page for pfn 0x80000
with virtual address ((struct page *)VMEMMAP_START - 0x2000), which is
below VMEMMAP_START as well as PCI_IO_END.

This commit fixes this bug by introducing a new variable
'vmemmap_start_pfn' which is aligned with memory section size and using
it to calculate vmemmap address instead of phys_ram_base.

Fixes: a11dd49dcb ("riscv: Sparse-Memory/vmemmap out-of-bounds fix")
Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20241209122617.53341-1-luxu.kernel@bytedance.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2025-01-08 10:45:34 -08:00
Björn Töpel
21f1b85c89 riscv: mm: Do not call pmd dtor on vmemmap page table teardown 
The vmemmap's, which is used for RV64 with SPARSEMEM_VMEMMAP, page
tables are populated using pmd (page middle directory) hugetables.
However, the pmd allocation is not using the generic mechanism used by
the VMA code (e.g. pmd_alloc()), or the RISC-V specific
create_pgd_mapping()/alloc_pmd_late(). Instead, the vmemmap page table
code allocates a page, and calls vmemmap_set_pmd(). This results in
that the pmd ctor is *not* called, nor would it make sense to do so.

Now, when tearing down a vmemmap page table pmd, the cleanup code
would unconditionally, and incorrectly call the pmd dtor, which
results in a crash (best case).

This issue was found when running the HMM selftests:

  | tools/testing/selftests/mm# ./test_hmm.sh smoke
  | ... # when unloading the test_hmm.ko module
  | page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10915b
  | flags: 0x1000000000000000(node=0|zone=1)
  | raw: 1000000000000000 0000000000000000 dead000000000122 0000000000000000
  | raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
  | page dumped because: VM_BUG_ON_PAGE(ptdesc->pmd_huge_pte)
  | ------------[ cut here ]------------
  | kernel BUG at include/linux/mm.h:3080!
  | Kernel BUG [#1]
  | Modules linked in: test_hmm(-) sch_fq_codel fuse drm drm_panel_orientation_quirks backlight dm_mod
  | CPU: 1 UID: 0 PID: 514 Comm: modprobe Tainted: G        W          6.12.0-00982-gf2a4f1682d07 #2
  | Tainted: [W]=WARN
  | Hardware name: riscv-virtio qemu/qemu, BIOS 2024.10 10/01/2024
  | epc : remove_pgd_mapping+0xbec/0x1070
  |  ra : remove_pgd_mapping+0xbec/0x1070
  | epc : ffffffff80010a68 ra : ffffffff80010a68 sp : ff20000000a73940
  |  gp : ffffffff827b2d88 tp : ff6000008785da40 t0 : ffffffff80fbce04
  |  t1 : 0720072007200720 t2 : 706d756420656761 s0 : ff20000000a73a50
  |  s1 : ff6000008915cff8 a0 : 0000000000000039 a1 : 0000000000000008
  |  a2 : ff600003fff0de20 a3 : 0000000000000000 a4 : 0000000000000000
  |  a5 : 0000000000000000 a6 : c0000000ffffefff a7 : ffffffff824469b8
  |  s2 : ff1c0000022456c0 s3 : ff1ffffffdbfffff s4 : ff6000008915c000
  |  s5 : ff6000008915c000 s6 : ff6000008915c000 s7 : ff1ffffffdc00000
  |  s8 : 0000000000000001 s9 : ff1ffffffdc00000 s10: ffffffff819a31f0
  |  s11: ffffffffffffffff t3 : ffffffff8000c950 t4 : ff60000080244f00
  |  t5 : ff60000080244000 t6 : ff20000000a73708
  | status: 0000000200000120 badaddr: ffffffff80010a68 cause: 0000000000000003
  | [<ffffffff80010a68>] remove_pgd_mapping+0xbec/0x1070
  | [<ffffffff80fd238e>] vmemmap_free+0x14/0x1e
  | [<ffffffff8032e698>] section_deactivate+0x220/0x452
  | [<ffffffff8032ef7e>] sparse_remove_section+0x4a/0x58
  | [<ffffffff802f8700>] __remove_pages+0x7e/0xba
  | [<ffffffff803760d8>] memunmap_pages+0x2bc/0x3fe
  | [<ffffffff02a3ca28>] dmirror_device_remove_chunks+0x2ea/0x518 [test_hmm]
  | [<ffffffff02a3e026>] hmm_dmirror_exit+0x3e/0x1018 [test_hmm]
  | [<ffffffff80102c14>] __riscv_sys_delete_module+0x15a/0x2a6
  | [<ffffffff80fd020c>] do_trap_ecall_u+0x1f2/0x266
  | [<ffffffff80fde0a2>] _new_vmalloc_restore_context_a0+0xc6/0xd2
  | Code: bf51 7597 0184 8593 76a5 854a 4097 0029 80e7 2c00 (9002) 7597
  | ---[ end trace 0000000000000000 ]---
  | Kernel panic - not syncing: Fatal exception in interrupt

Add a check to avoid calling the pmd dtor, if the calling context is
vmemmap_free().

Fixes: c75a74f4ba ("riscv: mm: Add memory hotplugging support")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20241120131203.1859787-1-bjorn@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-12-11 11:44:21 -08:00
Linus Torvalds
97d8894b6f Merge tag 'riscv-for-linus-6.12-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 
Pull RISC-V updates from Palmer Dabbelt:

 - Support using Zkr to seed KASLR

 - Support IPI-triggered CPU backtracing

 - Support for generic CPU vulnerabilities reporting to userspace

 - A few cleanups for missing licenses

 - The size limit on the XIP kernel has been removed

 - Support for tracing userspace stacks

 - Support for the Svvptc extension

 - Various cleanups and fixes throughout the tree

* tag 'riscv-for-linus-6.12-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (47 commits)
  crash: Fix riscv64 crash memory reserve dead loop
  perf/riscv-sbi: Add platform specific firmware event handling
  tools: Optimize ring buffer for riscv
  tools: Add riscv barrier implementation
  RISC-V: Don't have MAX_PHYSMEM_BITS exceed phys_addr_t
  ACPI: NUMA: initialize all values of acpi_early_node_map to NUMA_NO_NODE
  riscv: Enable bitops instrumentation
  riscv: Omit optimized string routines when using KASAN
  ACPI: RISCV: Make acpi_numa_get_nid() to be static
  riscv: Randomize lower bits of stack address
  selftests: riscv: Allow mmap test to compile on 32-bit
  riscv: Make riscv_isa_vendor_ext_andes array static
  riscv: Use LIST_HEAD() to simplify code
  riscv: defconfig: Disable RZ/Five peripheral support
  RISC-V: Implement kgdb_roundup_cpus() to enable future NMI Roundup
  riscv: avoid Imbalance in RAS
  riscv: cacheinfo: Add back init_cache_level() function
  riscv: Remove unused _TIF_WORK_MASK
  drivers/perf: riscv: Remove redundant macro check
  riscv: define ILLEGAL_POINTER_VALUE for 64bit
  ...
 2024-09-24 10:59:17 -07:00
Palmer Dabbelt
7e340f4fad Merge patch series "Svvptc extension to remove preventive sfence.vma" 
Alexandre Ghiti <alexghiti@rivosinc.com> says:

In RISC-V, after a new mapping is established, a sfence.vma needs to be
emitted for different reasons:

- if the uarch caches invalid entries, we need to invalidate it otherwise
  we would trap on this invalid entry,
- if the uarch does not cache invalid entries, a reordered access could fail
  to see the new mapping and then trap (sfence.vma acts as a fence).

We can actually avoid emitting those (mostly) useless and costly sfence.vma
by handling the traps instead:

- for new kernel mappings: only vmalloc mappings need to be taken care of,
  other new mapping are rare and already emit the required sfence.vma if
  needed.
  That must be achieved very early in the exception path as explained in
  patch 3, and this also fixes our fragile way of dealing with vmalloc faults.

- for new user mappings: Svvptc makes update_mmu_cache() a no-op but we can
  take some gratuitous page faults (which are very unlikely though).

Patch 1 and 2 introduce Svvptc extension probing.

On our uarch that does not cache invalid entries and a 6.5 kernel, the
gains are measurable:

* Kernel boot:                  6%
* ltp - mmapstress01:           8%
* lmbench - lat_pagefault:      20%
* lmbench - lat_mmap:           5%

Here are the corresponding numbers of sfence.vma emitted:

* Ubuntu boot to login:
Before: ~630k sfence.vma
After:  ~200k sfence.vma

* ltp - mmapstress01
Before: ~45k
After:  ~6.3k

* lmbench - lat_pagefault
Before: ~665k
After:   832 (!)

* lmbench - lat_mmap
Before: ~546k
After:   718 (!)

Thanks to Ved and Matt Evans for triggering the discussion that led to
this patchset!

* b4-shazam-merge:
  riscv: Stop emitting preventive sfence.vma for new userspace mappings with Svvptc
  riscv: Stop emitting preventive sfence.vma for new vmalloc mappings
  dt-bindings: riscv: Add Svvptc ISA extension description
  riscv: Add ISA extension parsing for Svvptc

Link: https://lore.kernel.org/r/20240717060125.139416-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-15 20:58:24 -07:00
Alexandre Ghiti
503638e0ba riscv: Stop emitting preventive sfence.vma for new vmalloc mappings 
In 6.5, we removed the vmalloc fault path because that can't work (see
[1] [2]). Then in order to make sure that new page table entries were
seen by the page table walker, we had to preventively emit a sfence.vma
on all harts [3] but this solution is very costly since it relies on IPI.

And even there, we could end up in a loop of vmalloc faults if a vmalloc
allocation is done in the IPI path (for example if it is traced, see
[4]), which could result in a kernel stack overflow.

Those preventive sfence.vma needed to be emitted because:

- if the uarch caches invalid entries, the new mapping may not be
  observed by the page table walker and an invalidation may be needed.
- if the uarch does not cache invalid entries, a reordered access
  could "miss" the new mapping and traps: in that case, we would actually
  only need to retry the access, no sfence.vma is required.

So this patch removes those preventive sfence.vma and actually handles
the possible (and unlikely) exceptions. And since the kernel stacks
mappings lie in the vmalloc area, this handling must be done very early
when the trap is taken, at the very beginning of handle_exception: this
also rules out the vmalloc allocations in the fault path.

Link: https://lore.kernel.org/linux-riscv/20230531093817.665799-1-bjorn@kernel.org/ [1]
Link: https://lore.kernel.org/linux-riscv/20230801090927.2018653-1-dylan@andestech.com [2]
Link: https://lore.kernel.org/linux-riscv/20230725132246.817726-1-alexghiti@rivosinc.com/ [3]
Link: https://lore.kernel.org/lkml/20200508144043.13893-1-joro@8bytes.org/ [4]
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Yunhui Cui <cuiyunhui@bytedance.com>
Link: https://lore.kernel.org/r/20240717060125.139416-4-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-15 00:11:04 -07:00
Stuart Menefy
d6a1928134 riscv: Remove redundant restriction on memory size 
The original reason for reserving the top 4GiB of the direct map
(space for modules/BPF/kernel) hasn't applied since the address
map was reworked for KASAN.

Signed-off-by: Stuart Menefy <stuart.menefy@codasip.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240624121723.2186279-1-stuart.menefy@codasip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-14 01:08:56 -07:00
Palmer Dabbelt
9ea7b92b77 Merge patch series "remove size limit on XIP kernel" 
Nam Cao <namcao@linutronix.de> says:

Hi,

For XIP kernel, the writable data section is always at offset specified in
XIP_OFFSET, which is hard-coded to 32MB.

Unfortunately, this means the read-only section (placed before the
writable section) is restricted in size. This causes build failure if the
kernel gets too large.

This series remove the use of XIP_OFFSET one by one, then remove this
macro entirely at the end, with the goal of lifting this size restriction.

Also some cleanup and documentation along the way.

* b4-shazam-merge
  riscv: remove limit on the size of read-only section for XIP kernel
  riscv: drop the use of XIP_OFFSET in create_kernel_page_table()
  riscv: drop the use of XIP_OFFSET in kernel_mapping_va_to_pa()
  riscv: drop the use of XIP_OFFSET in XIP_FIXUP_FLASH_OFFSET
  riscv: drop the use of XIP_OFFSET in XIP_FIXUP_OFFSET
  riscv: replace misleading va_kernel_pa_offset on XIP kernel
  riscv: don't export va_kernel_pa_offset in vmcoreinfo for XIP kernel
  riscv: cleanup XIP_FIXUP macro
  riscv: change XIP's kernel_map.size to be size of the entire kernel
  ...

Link: https://lore.kernel.org/r/cover.1717789719.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-12 07:23:05 -07:00
Nam Cao
a7cfb99943 riscv: drop the use of XIP_OFFSET in create_kernel_page_table() 
XIP_OFFSET is the hard-coded offset of writable data section within the
kernel.

By hard-coding this value, the read-only section of the kernel (which is
placed before the writable data section) is restricted in size.

As a preparation to remove this hard-coded value entirely, stop using
XIP_OFFSET in create_kernel_page_table(). Instead use _sdata and _start to
do the same thing.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/4ea3f222a7eb9f91c04b155ff2e4d3ef19158acc.1717789719.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-12 07:23:01 -07:00
Nam Cao
5cf0896721 riscv: replace misleading va_kernel_pa_offset on XIP kernel 
On XIP kernel, the name "va_kernel_pa_offset" is misleading: unlike
"normal" kernel, it is not the virtual-physical address offset of kernel
mapping, it is the offset of kernel mapping's first virtual address to
first physical address in DRAM, which is not meaningful because the
kernel's first physical address is not in DRAM.

For XIP kernel, there are 2 different offsets because the read-only part of
the kernel resides in ROM while the rest is in RAM. The offset to ROM is in
kernel_map.va_kernel_xip_pa_offset, while the offset to RAM is not stored
anywhere: it is calculated on-the-fly.

Remove this confusing "va_kernel_pa_offset" and add
"va_kernel_xip_data_pa_offset" as its replacement. This new variable is the
offset of virtual mapping of the kernel's data portion to the corresponding
physical addresses.

With the introduction of this new variable, also rename
va_kernel_xip_pa_offset -> va_kernel_xip_text_pa_offset to make it clear
that this one is about the .text section.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/84e5d005c1386d88d7b2531e0b6707ec5352ee54.1717789719.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-12 07:22:57 -07:00
Alexandre Ghiti
5f771088a2 riscv: Do not restrict memory size because of linear mapping on nommu 
It makes no sense to restrict physical memory size because of linear
mapping size constraints when there is no linear mapping, so only do
that when mmu is enabled.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Closes: https://lore.kernel.org/linux-riscv/CAMuHMdW0bnJt5GMRtOZGkTiM7GK4UaLJCDMF_Ouq++fnDKi3_A@mail.gmail.com/
Fixes: 3b6564427a ("riscv: Fix linear mapping checks for non-contiguous memory regions")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20240827065230.145021-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-09-03 07:57:27 -07:00
Nam Cao
57d76bc51f riscv: change XIP's kernel_map.size to be size of the entire kernel 
With XIP kernel, kernel_map.size is set to be only the size of data part of
the kernel. This is inconsistent with "normal" kernel, who sets it to be
the size of the entire kernel.

More importantly, XIP kernel fails to boot if CONFIG_DEBUG_VIRTUAL is
enabled, because there are checks on virtual addresses with the assumption
that kernel_map.size is the size of the entire kernel (these checks are in
arch/riscv/mm/physaddr.c).

Change XIP's kernel_map.size to be the size of the entire kernel.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: <stable@vger.kernel.org> # v6.1+
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240508191917.2892064-1-namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-08-14 13:12:33 -07:00
Palmer Dabbelt
7c08a2615f Merge patch series "RISC-V: Parse DT for Zkr to seed KASLR" 
Jesse Taube <jesse@rivosinc.com> says:

Add functions to pi/fdt_early.c to help parse the FDT to check if
the isa string has the Zkr extension. Then use the Zkr extension to
seed the KASLR base address.

The first two patches fix the visibility of symbols.

* b4-shazam-merge:
  RISC-V: Use Zkr to seed KASLR base address
  RISC-V: pi: Add kernel/pi/pi.h
  RISC-V: lib: Add pi aliases for string functions
  RISC-V: pi: Force hidden visibility for all symbol references

Link: https://lore.kernel.org/r/20240709173937.510084-1-jesse@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-08-05 12:06:43 -07:00
Jesse Taube
945302df3d RISC-V: Use Zkr to seed KASLR base address 
Parse the device tree for Zkr in the isa string.
If Zkr is present, use it to seed the kernel base address.

On an ACPI system, as of this commit, there is no easy way to check if
Zkr is present. Blindly running the instruction isn't an option as;
we have to be able to trust the firmware.

Signed-off-by: Jesse Taube <jesse@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240709173937.510084-5-jesse@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-08-05 12:06:41 -07:00
Stuart Menefy
3b6564427a riscv: Fix linear mapping checks for non-contiguous memory regions 
The RISC-V kernel already has checks to ensure that memory which would
lie outside of the linear mapping is not used. However those checks
use memory_limit, which is used to implement the mem= kernel command
line option (to limit the total amount of memory, not its address
range). When memory is made up of two or more non-contiguous memory
banks this check is incorrect.

Two changes are made here:
 - add a call in setup_bootmem() to memblock_cap_memory_range() which
   will cause any memory which falls outside the linear mapping to be
   removed from the memory regions.
 - remove the check in create_linear_mapping_page_table() which was
   intended to remove memory which is outside the liner mapping based
   on memory_limit, as it is no longer needed. Note a check for
   mapping more memory than memory_limit (to implement mem=) is
   unnecessary because of the existing call to
   memblock_enforce_memory_limit().

This issue was seen when booting on a SV39 platform with two memory
banks:
  0x00,80000000 1GiB
  0x20,00000000 32GiB
This memory range is 158GiB from top to bottom, but the linear mapping
is limited to 128GiB, so the lower block of RAM will be mapped at
PAGE_OFFSET, and the upper block straddles the top of the linear
mapping.

This causes the following Oops:
[    0.000000] Linux version 6.10.0-rc2-gd3b8dd5b51dd-dirty (stuart.menefy@codasip.com) (riscv64-codasip-linux-gcc (GCC) 13.2.0, GNU ld (GNU Binutils) 2.41.0.20231213) #20 SMP Sat Jun 22 11:34:22 BST 2024
[    0.000000] memblock_add: [0x0000000080000000-0x00000000bfffffff] early_init_dt_add_memory_arch+0x4a/0x52
[    0.000000] memblock_add: [0x0000002000000000-0x00000027ffffffff] early_init_dt_add_memory_arch+0x4a/0x52
...
[    0.000000] memblock_alloc_try_nid: 23724 bytes align=0x8 nid=-1 from=0x0000000000000000 max_addr=0x0000000000000000 early_init_dt_alloc_memory_arch+0x1e/0x48
[    0.000000] memblock_reserve: [0x00000027ffff5350-0x00000027ffffaffb] memblock_alloc_range_nid+0xb8/0x132
[    0.000000] Unable to handle kernel paging request at virtual address fffffffe7fff5350
[    0.000000] Oops [#1]
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.10.0-rc2-gd3b8dd5b51dd-dirty #20
[    0.000000] Hardware name: codasip,a70x (DT)
[    0.000000] epc : __memset+0x8c/0x104
[    0.000000]  ra : memblock_alloc_try_nid+0x74/0x84
[    0.000000] epc : ffffffff805e88c8 ra : ffffffff806148f6 sp : ffffffff80e03d50
[    0.000000]  gp : ffffffff80ec4158 tp : ffffffff80e0bec0 t0 : fffffffe7fff52f8
[    0.000000]  t1 : 00000027ffffb000 t2 : 5f6b636f6c626d65 s0 : ffffffff80e03d90
[    0.000000]  s1 : 0000000000005cac a0 : fffffffe7fff5350 a1 : 0000000000000000
[    0.000000]  a2 : 0000000000005cac a3 : fffffffe7fffaff8 a4 : 000000000000002c
[    0.000000]  a5 : ffffffff805e88c8 a6 : 0000000000005cac a7 : 0000000000000030
[    0.000000]  s2 : fffffffe7fff5350 s3 : ffffffffffffffff s4 : 0000000000000000
[    0.000000]  s5 : ffffffff8062347e s6 : 0000000000000000 s7 : 0000000000000001
[    0.000000]  s8 : 0000000000002000 s9 : 00000000800226d0 s10: 0000000000000000
[    0.000000]  s11: 0000000000000000 t3 : ffffffff8080a928 t4 : ffffffff8080a928
[    0.000000]  t5 : ffffffff8080a928 t6 : ffffffff8080a940
[    0.000000] status: 0000000200000100 badaddr: fffffffe7fff5350 cause: 000000000000000f
[    0.000000] [<ffffffff805e88c8>] __memset+0x8c/0x104
[    0.000000] [<ffffffff8062349c>] early_init_dt_alloc_memory_arch+0x1e/0x48
[    0.000000] [<ffffffff8043e892>] __unflatten_device_tree+0x52/0x114
[    0.000000] [<ffffffff8062441e>] unflatten_device_tree+0x9e/0xb8
[    0.000000] [<ffffffff806046fe>] setup_arch+0xd4/0x5bc
[    0.000000] [<ffffffff806007aa>] start_kernel+0x76/0x81a
[    0.000000] Code: b823 02b2 bc23 02b2 b023 04b2 b423 04b2 b823 04b2 (bc23) 04b2
[    0.000000] ---[ end trace 0000000000000000 ]---
[    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[    0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---

The problem is that memblock (unaware that some physical memory cannot
be used) has allocated memory from the top of memory but which is
outside the linear mapping region.

Signed-off-by: Stuart Menefy <stuart.menefy@codasip.com>
Fixes: c99127c452 ("riscv: Make sure the linear mapping does not use the kernel mapping")
Reviewed-by: David McKay <david.mckay@codasip.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240622114217.2158495-1-stuart.menefy@codasip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-08-01 11:46:09 -07:00
Linus Torvalds
f557af081d Merge tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 
Pull RISC-V updates from Palmer Dabbelt:

 - Support for various new ISA extensions:
     * The Zve32[xf] and Zve64[xfd] sub-extensios of the vector
       extension
     * Zimop and Zcmop for may-be-operations
     * The Zca, Zcf, Zcd and Zcb sub-extensions of the C extension
     * Zawrs

 - riscv,cpu-intc is now dtschema

 - A handful of performance improvements and cleanups to text patching

 - Support for memory hot{,un}plug

 - The highest user-allocatable virtual address is now visible in
   hwprobe

* tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (58 commits)
  riscv: lib: relax assembly constraints in hweight
  riscv: set trap vector earlier
  KVM: riscv: selftests: Add Zawrs extension to get-reg-list test
  KVM: riscv: Support guest wrs.nto
  riscv: hwprobe: export Zawrs ISA extension
  riscv: Add Zawrs support for spinlocks
  dt-bindings: riscv: Add Zawrs ISA extension description
  riscv: Provide a definition for 'pause'
  riscv: hwprobe: export highest virtual userspace address
  riscv: Improve sbi_ecall() code generation by reordering arguments
  riscv: Add tracepoints for SBI calls and returns
  riscv: Optimize crc32 with Zbc extension
  riscv: Enable DAX VMEMMAP optimization
  riscv: mm: Add support for ZONE_DEVICE
  virtio-mem: Enable virtio-mem for RISC-V
  riscv: Enable memory hotplugging for RISC-V
  riscv: mm: Take memory hotplug read-lock during kernel page table dump
  riscv: mm: Add memory hotplugging support
  riscv: mm: Add pfn_to_kaddr() implementation
  riscv: mm: Refactor create_linear_mapping_range() for memory hot add
  ...
 2024-07-20 09:11:27 -07:00
Björn Töpel
c75a74f4ba riscv: mm: Add memory hotplugging support 
For an architecture to support memory hotplugging, a couple of
callbacks needs to be implemented:

 arch_add_memory()
  This callback is responsible for adding the physical memory into the
  direct map, and call into the memory hotplugging generic code via
  __add_pages() that adds the corresponding struct page entries, and
  updates the vmemmap mapping.

 arch_remove_memory()
  This is the inverse of the callback above.

 vmemmap_free()
  This function tears down the vmemmap mappings (if
  CONFIG_SPARSEMEM_VMEMMAP is enabled), and also deallocates the
  backing vmemmap pages. Note that for persistent memory, an
  alternative allocator for the backing pages can be used; The
  vmem_altmap. This means that when the backing pages are cleared,
  extra care is needed so that the correct deallocation method is
  used.

 arch_get_mappable_range()
  This functions returns the PA range that the direct map can map.
  Used by the MHP internals for sanity checks.

The page table unmap/teardown functions are heavily based on code from
the x86 tree. The same remove_pgd_mapping() function is used in both
vmemmap_free() and arch_remove_memory(), but in the latter function
the backing pages are not removed.

Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240605114100.315918-7-bjorn@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-06-26 08:42:42 -07:00
Björn Töpel
007480fe84 riscv: mm: Refactor create_linear_mapping_range() for memory hot add 
Add a parameter to the direct map setup function, so it can be used in
arch_add_memory() later.

Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240605114100.315918-5-bjorn@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-06-26 08:42:40 -07:00
Björn Töpel
fe122b89da riscv: mm: Change attribute from __init to __meminit for page functions 
Prepare for memory hotplugging support by changing from __init to
__meminit for the page table functions that are used by the upcoming
architecture specific callbacks.

Changing the __init attribute to __meminit, avoids that the functions
are removed after init. The __meminit attribute makes sure the
functions are kept in the kernel text post init, but only if memory
hotplugging is enabled for the build.

Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240605114100.315918-4-bjorn@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
 2024-06-26 08:42:39 -07:00