Pull x86 entry code updates from Dave Hansen:
"This is entirely composed of a set of long overdue VDSO cleanups. They
makes the VDSO build much more logical and zap quite a bit of old
cruft.
It also results in a coveted net-code-removal diffstat"
* tag 'x86_entry_for_7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/vdso: Add vdso2c to .gitignore
x86/entry/vdso32: Omit '.cfi_offset eflags' for LLVM < 16
MAINTAINERS: Adjust vdso file entry in INTEL SGX
x86/entry/vdso/selftest: Update location of vgetrandom-chacha.S
x86/entry/vdso: Fix filtering of vdso compiler flags
x86/entry/vdso: Update the object paths for "make vdso_install"
x86/entry/vdso32: When using int $0x80, use it directly
x86/cpufeature: Replace X86_FEATURE_SYSENTER32 with X86_FEATURE_SYSFAST32
x86/vdso: Abstract out vdso system call internals
x86/entry/vdso: Include GNU_PROPERTY and GNU_STACK PHDRs
x86/entry/vdso32: Remove open-coded DWARF in sigreturn.S
x86/entry/vdso32: Remove SYSCALL_ENTER_KERNEL macro in sigreturn.S
x86/entry/vdso32: Don't rely on int80_landing_pad for adjusting ip
x86/entry/vdso: Refactor the vdso build
x86/entry/vdso: Move vdso2c to arch/x86/tools
x86/entry/vdso: Rename vdso_image_* to vdso*_image
Pull VDSO updates from Thomas Gleixner:
- Provide the missing 64-bit variant of clock_getres()
This allows the extension of CONFIG_COMPAT_32BIT_TIME to the vDSO and
finally the removal of 32-bit time types from the kernel and UAPI.
- Remove the useless and broken getcpu_cache from the VDSO
The intention was to provide a trivial way to retrieve the CPU number
from the VDSO, but as the VDSO data is per process there is no way to
make it work.
- Switch get/put_unaligned() from packed struct to memcpy()
The packed struct violates strict aliasing rules which requires to
pass -fno-strict-aliasing to the compiler. As this are scalar values
__builtin_memcpy() turns them into simple loads and stores
- Use __typeof_unqual__() for __unqual_scalar_typeof()
The get/put_unaligned() changes triggered a new sparse warning when
__beNN types are used with get/put_unaligned() as sparse builds add a
special 'bitwise' attribute to them which prevents sparse to evaluate
the Generic in __unqual_scalar_typeof().
Newer sparse versions support __typeof_unqual__() which avoids the
problem, but requires a recent sparse install. So this adds a sanity
check to sparse builds, which validates that sparse is available and
capable of handling it.
- Force inline __cvdso_clock_getres_common()
Compilers sometimes un-inline agressively, which results in function
call overhead and problems with automatic stack variable
initialization.
Interestingly enough the force inlining results in smaller code than
the un-inlined variant produced by GCC when optimizing for size.
* tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
vdso/gettimeofday: Force inlining of __cvdso_clock_getres_common()
x86/percpu: Make CONFIG_USE_X86_SEG_SUPPORT work with sparse
compiler: Use __typeof_unqual__() for __unqual_scalar_typeof()
powerpc/vdso: Provide clock_getres_time64()
tools headers: Remove unneeded ignoring of warnings in unaligned.h
tools headers: Update the linux/unaligned.h copy with the kernel sources
vdso: Switch get/put_unaligned() from packed struct to memcpy()
parisc: Inline a type punning version of get_unaligned_le32()
vdso: Remove struct getcpu_cache
MIPS: vdso: Provide getres_time64() for 32-bit ABIs
arm64: vdso32: Provide clock_getres_time64()
ARM: VDSO: Provide clock_getres_time64()
ARM: VDSO: Patch out __vdso_clock_getres() if unavailable
x86/vdso: Provide clock_getres_time64() for x86-32
selftests: vDSO: vdso_test_abi: Add test for clock_getres_time64()
selftests: vDSO: vdso_test_abi: Use UAPI system call numbers
selftests: vDSO: vdso_config: Add configurations for clock_getres_time64()
vdso: Add prototype for __vdso_clock_getres_time64()
The s390 vDSO source directory was recently moved,
but this reference was not updated.
Fixes: c0087d807a ("s390/vdso: Rename vdso64 to vdso")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The cache parameter of getcpu() is useless nowadays for various reasons.
* It is never passed by userspace for either the vDSO or syscalls.
* It is never used by the kernel.
* It could not be made to work on the current vDSO architecture.
* The structure definition is not part of the UAPI headers.
* vdso_getcpu() is superseded by restartable sequences in any case.
Remove the struct and its header.
As a side-effect this gets rid of an unwanted inclusion of the linux/
header namespace from vDSO code.
[ tglx: Adapt to s390 upstream changes */
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Link: https://patch.msgid.link/20251230-getcpu_cache-v3-1-fb9c5f880ebe@linutronix.de
Pull non-MM updates from Andrew Morton:
- "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko)
fixes a build issue and does some cleanup in ib/sys_info.c
- "Implement mul_u64_u64_div_u64_roundup()" (David Laight)
enhances the 64-bit math code on behalf of a PWM driver and beefs up
the test module for these library functions
- "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich)
makes BPF symbol names, sizes, and line numbers available to the GDB
debugger
- "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang)
adds a sysctl which can be used to cause additional info dumping when
the hung-task and lockup detectors fire
- "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu)
adds a general base64 encoder/decoder to lib/ and migrates several
users away from their private implementations
- "rbree: inline rb_first() and rb_last()" (Eric Dumazet)
makes TCP a little faster
- "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin)
reworks the KEXEC Handover interfaces in preparation for Live Update
Orchestrator (LUO), and possibly for other future clients
- "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin)
increases the flexibility of KEXEC Handover. Also preparation for LUO
- "Live Update Orchestrator" (Pasha Tatashin)
is a major new feature targeted at cloud environments. Quoting the
cover letter:
This series introduces the Live Update Orchestrator, a kernel
subsystem designed to facilitate live kernel updates using a
kexec-based reboot. This capability is critical for cloud
environments, allowing hypervisors to be updated with minimal
downtime for running virtual machines. LUO achieves this by
preserving the state of selected resources, such as memory,
devices and their dependencies, across the kernel transition.
As a key feature, this series includes support for preserving
memfd file descriptors, which allows critical in-memory data, such
as guest RAM or any other large memory region, to be maintained in
RAM across the kexec reboot.
Mike Rappaport merits a mention here, for his extensive review and
testing work.
- "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain)
moves the kexec and kdump sysfs entries from /sys/kernel/ to
/sys/kernel/kexec/ and adds back-compatibility symlinks which can
hopefully be removed one day
- "kho: fixes for vmalloc restoration" (Mike Rapoport)
fixes a BUG which was being hit during KHO restoration of vmalloc()
regions
* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
calibrate: update header inclusion
Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
vmcoreinfo: track and log recoverable hardware errors
kho: fix restoring of contiguous ranges of order-0 pages
kho: kho_restore_vmalloc: fix initialization of pages array
MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
init: replace simple_strtoul with kstrtoul to improve lpj_setup
KHO: fix boot failure due to kmemleak access to non-PRESENT pages
Documentation/ABI: new kexec and kdump sysfs interface
Documentation/ABI: mark old kexec sysfs deprecated
kexec: move sysfs entries to /sys/kernel/kexec
test_kho: always print restore status
kho: free chunks using free_page() instead of kfree()
selftests/liveupdate: add kexec test for multiple and empty sessions
selftests/liveupdate: add simple kexec-based selftest for LUO
selftests/liveupdate: add userspace API selftests
docs: add documentation for memfd preservation via LUO
mm: memfd_luo: allow preserving memfd
liveupdate: luo_file: add private argument to store runtime state
mm: shmem: export some functions to internal.h
...
Remove s390 compat support from everything within tools, since s390 compat
support will be removed from the kernel.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Weißschuh <linux@weissschuh.net> # tools/nolibc selftests/nolibc
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> # selftests/vDSO
Acked-by: Alexei Starovoitov <ast@kernel.org> # bpf bits
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
If AT_SYSINFO_EHDR is missing the whole test needs to be skipped.
Currently this results in the following output:
TAP version 13
1..16
# AT_SYSINFO_EHDR is not present!
This output is incorrect, as "1..16" still requires the subtest lines to
be printed, which isn't done however.
Switch to the correct skipping functions, so the output now correctly
indicates that no subtests are being run:
TAP version 13
1..0 # SKIP AT_SYSINFO_EHDR is not present!
Fixes: 693f5ca08c ("kselftest: Extend vDSO selftest")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-2-90f499dd35f8@linutronix.de
The _rval register variable is meant to be an output operand of the asm
statement but is instead used as input operand.
clang 20.1 notices this and triggers -Wuninitialized warnings:
tools/testing/selftests/timers/auxclock.c:154:10: error: variable '_rval' is uninitialized when used here [-Werror,-Wuninitialized]
154 | return VDSO_CALL(self->vdso_clock_gettime64, 2, clockid, ts);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tools/testing/selftests/timers/../vDSO/vdso_call.h:59:10: note: expanded from macro 'VDSO_CALL'
59 | : "r" (_rval) \
| ^~~~~
tools/testing/selftests/timers/auxclock.c:154:10: note: variable '_rval' is declared here
tools/testing/selftests/timers/../vDSO/vdso_call.h:47:2: note: expanded from macro 'VDSO_CALL'
47 | register long _rval asm ("r3"); \
| ^
It seems the list of input and output operands have been switched around.
However as the argument registers are not always initialized they can not
be marked as pure inputs as that would trigger -Wuninitialized warnings.
Adding _rval as another input and output operand does also not work as it
would collide with the existing _r3 variable.
Instead reuse _r3 for both the argument and the return value.
Fixes: 6eda706a53 ("selftests: vDSO: fix the way vDSO functions are called for powerpc")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-1-90f499dd35f8@linutronix.de
Closes: https://lore.kernel.org/oe-kbuild-all/202506180223.BOOk5jDK-lkp@intel.com/
Functions definitions without any argument list produce a warning with
-Wstrict-prototypes:
vdso_test_correctness.c:111:13: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
111 | static void fill_function_pointers()
| ^~~~~~~~~~~~~~~~~~~~~~
Explicitly use an empty argument list.
Now that all selftests a free of this warning, enable it in the Makefile.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-7-e62e37a6bcf5@linutronix.de
According to kselftest.h ksft_exit_skip() is not meant to be called when
a plan has already been printed.
Use the recommended function ksft_test_result_skip().
This fixes a bug, where the TAP output would be invalid when skipping:
TAP version 13
1..1
ok 2 # SKIP Not implemented on architecture
The SKIP line should start with "ok 1" as the plan only contains one test.
Fixes: 3b5992eaf7 ("selftests: vDSO: unconditionally build chacha test")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-1-e62e37a6bcf5@linutronix.de
Hook up the generic vDSO implementation to the generic vDSO getrandom
implementation by providing the required __arch_chacha20_blocks_nostack
and getrandom_syscall implementations. Also wire up the selftests.
The benchmark result:
vdso: 25000000 times in 2.466341333 seconds
libc: 25000000 times in 41.447720005 seconds
syscall: 25000000 times in 41.043926672 seconds
vdso: 25000000 x 256 times in 162.286219353 seconds
libc: 25000000 x 256 times in 2953.855018685 seconds
syscall: 25000000 x 256 times in 2796.268546000 seconds
[ alex: - Fix dynamic relocation
- Squash Nathan's fix https://lore.kernel.org/all/20250423-riscv-fix-compat_vdso-lld-v2-1-b7bbbc244501@kernel.org/
- Add comment from Loongarch ]
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Link: https://lore.kernel.org/r/20250411024600.16045-1-xry111@xry111.site
Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Pull VDSO infrastructure updates from Thomas Gleixner:
- Consolidate the VDSO storage
The VDSO data storage and data layout has been largely architecture
specific for historical reasons. That increases the maintenance
effort and causes inconsistencies over and over.
There is no real technical reason for architecture specific layouts
and implementations. The architecture specific details can easily be
integrated into a generic layout, which also reduces the amount of
duplicated code for managing the mappings.
Convert all architectures over to a unified layout and common mapping
infrastructure. This splits the VDSO data layout into subsystem
specific blocks, timekeeping, random and architecture parts, which
provides a better structure and allows to improve and update the
functionalities without conflict and interaction.
- Rework the timekeeping data storage
The current implementation is designed for exposing system
timekeeping accessors, which was good enough at the time when it was
designed.
PTP and Time Sensitive Networking (TSN) change that as there are
requirements to expose independent PTP clocks, which are not related
to system timekeeping.
Replace the monolithic data storage by a structured layout, which
allows to add support for independent PTP clocks on top while reusing
both the data structures and the time accessor implementations.
* tag 'timers-vdso-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
sparc/vdso: Always reject undefined references during linking
x86/vdso: Always reject undefined references during linking
vdso: Rework struct vdso_time_data and introduce struct vdso_clock
vdso: Move architecture related data before basetime data
powerpc/vdso: Prepare introduction of struct vdso_clock
arm64/vdso: Prepare introduction of struct vdso_clock
x86/vdso: Prepare introduction of struct vdso_clock
time/namespace: Prepare introduction of struct vdso_clock
vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock struct
vdso/vsyscall: Prepare introduction of struct vdso_clock
vdso/gettimeofday: Prepare helper functions for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_coarse_timens() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_coarse() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_hres_timens() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_hres() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare introduction of struct vdso_clock
vdso/helpers: Prepare introduction of struct vdso_clock
vdso/datapage: Define vdso_clock to prepare for multiple PTP clocks
vdso: Make vdso_time_data cacheline aligned
arm64: Make asm/cache.h compatible with vDSO
...
Commit 14be4e6f35 ("selftests: vDSO: fix ELF hash table entry size for s390x")
changed the type of the ELF hash table entries to 64bit on s390x.
However the *GNU* hash tables entries are always 32bit.
The "bucket" pointer is shared between both hash algorithms.
On s390, this caused the GNU hash algorithm to access its 32-bit entries as if they
were 64-bit, triggering compiler warnings (assignment between "Elf64_Xword *" and
"Elf64_Word *") and runtime crashes.
Introduce a new dedicated "gnu_bucket" pointer which is used by the GNU hash.
Fixes: e0746bde6f ("selftests/vDSO: support DT_GNU_HASH")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250217-selftests-vdso-s390-gnu-hash-v2-1-f6c2532ffe2a@linutronix.de
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull powerpc updates from Michael Ellerman:
- Rework kfence support for the HPT MMU to work on systems with >= 16TB
of RAM.
- Remove the powerpc "maple" platform, used by the "Yellow Dog
Powerstation".
- Add support for DYNAMIC_FTRACE_WITH_CALL_OPS,
DYNAMIC_FTRACE_WITH_DIRECT_CALLS & BPF Trampolines.
- Add support for running KVM nested guests on Power11.
- Other small features, cleanups and fixes.
Thanks to Amit Machhiwal, Arnd Bergmann, Christophe Leroy, Costa
Shulyupin, David Hunter, David Wang, Disha Goel, Gautam Menghani, Geert
Uytterhoeven, Hari Bathini, Julia Lawall, Kajol Jain, Keith Packard,
Lukas Bulwahn, Madhavan Srinivasan, Markus Elfring, Michal Suchanek,
Ming Lei, Mukesh Kumar Chaurasiya, Nathan Chancellor, Naveen N Rao,
Nicholas Piggin, Nysal Jan K.A, Paulo Miguel Almeida, Pavithra Prakash,
Ritesh Harjani (IBM), Rob Herring (Arm), Sachin P Bappalige, Shen
Lichuan, Simon Horman, Sourabh Jain, Thomas Weißschuh, Thorsten Blum,
Thorsten Leemhuis, Venkat Rao Bagalkote, Zhang Zekun, and zhang jiao.
* tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (89 commits)
EDAC/powerpc: Remove PPC_MAPLE drivers
powerpc/perf: Add per-task/process monitoring to vpa_pmu driver
powerpc/kvm: Add vpa latency counters to kvm_vcpu_arch
docs: ABI: sysfs-bus-event_source-devices-vpa-pmu: Document sysfs event format entries for vpa_pmu
powerpc/perf: Add perf interface to expose vpa counters
MAINTAINERS: powerpc: Mark Maddy as "M"
powerpc/Makefile: Allow overriding CPP
powerpc-km82xx.c: replace of_node_put() with __free
ps3: Correct some typos in comments
powerpc/kexec: Fix return of uninitialized variable
macintosh: Use common error handling code in via_pmu_led_init()
powerpc/powermac: Use of_property_match_string() in pmac_has_backlight_type()
powerpc: remove dead config options for MPC85xx platform support
powerpc/xive: Use cpumask_intersects()
selftests/powerpc: Remove the path after initialization.
powerpc/xmon: symbol lookup length fixed
powerpc/ep8248e: Use %pa to format resource_size_t
powerpc/ps3: Reorganize kerneldoc parameter names
KVM: PPC: Book3S HV: Fix kmv -> kvm typo
powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static
...
On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.
$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: PowerPC64
Version: 0x1
...
Symbol table '.dynsym' contains 12 entries:
Num: Value Size Type Bind Vis Ndx Name
...
1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
...
4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
Symbol table '.symtab' contains 56 entries:
Num: Value Size Type Bind Vis Ndx Name
...
45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu
47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres
To overcome that, commit ba83b3239e ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.
The original commit that brought VDSO support into powerpc/64 has the
following explanation:
Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
can't be expected to link against them directly, the vDSO's are both seen
as if they were linked at 0 and the symbols just contain offsets to the
various functions. This is done on purpose to avoid a relocation step
(ppc64 functions normally have descriptors with abs addresses in them).
When glibc uses those functions, it's expected to use it's own trampolines
that know how to reach them.
The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.
glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.
For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.
So lets flag VDSO entry points as functions and revert the
selftest change.
Link: 5f2dd691b6
Fixes: ba83b3239e ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-By: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
The previous commit introduced the use of CLONE_NEWTIME without including
<sched.h> which contains its definition.
Add an explicit include of <sched.h> to ensure that CLONE_NEWTIME
is correctly defined before it is used.
Fixes: 2aec90036d ("selftests: vDSO: ensure vgetrandom works in a time namespace")
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Improve the error and skip condition messages to let the developer know
precisely where a test has failed. Also make better use of the ksft api
for this.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Rather than building on supported archs, build on all archs, and then
use the presence of the symbol in the vDSO to either skip the test or
move forward with it.
Note that this means that this test no longer checks whether the symbol
was correctly added to the kernel. But hopefully this will be clear
enough to developers and we'll cross our fingers that symbols aren't
removed by accident and not caught after this change.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Rather than using symlinks to find the vgetrandom-chacha.S file for each
arch, store this in a file that uses the compiler to determine
architecture, and then make use of weak symbols to skip the test on
architectures that don't provide the code.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This prevents false sharing, which makes a large difference on machines
with several NUMA nodes, such as on a dual socket Intel(R) Xeon(R) Gold
6338 CPU @ 2.00GHz, where the "bench-multi" test goes from 2.7s down to
1.9s. While this is just test code, it also forms the basis of how folks
will wind up implementing this in libraries, so we should implement this
simple cache alignment improvement here.
Suggested-by: Florian Weimer <fweimer@redhat.com>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull kselftest fix from Shuah Khan:
"One urgent fix to vDSO as automated testing is failing due to this
bug"
* tag 'linux_kselftest-next-6.12-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests: vDSO: align stack for O2-optimized memcpy
Some archs -- arm64 and s390x -- implemented chacha using instructions
that are available most places, but aren't always available. The kernel
handles this just fine, but the selftest does not. Check the hwcaps
before running, and skip the test if the cpu doesn't support it. As
well, on s390x, always emit the fallback instructions of an alternative
block, to ensure maximum compatibility.
Co-developed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Provide the s390 specific vdso getrandom() architecture backend.
_vdso_rng_data required data is placed within the _vdso_data vvar page,
by using a hardcoded offset larger than vdso_data.
As required the chacha20 implementation does not write to the stack.
The implementation follows more or less the arm64 implementations and
makes use of vector instructions. It has a fallback to the getrandom()
system call for machines where the vector facility is not installed.
The check if the vector facility is installed, as well as an
optimization for machines with the vector-enhancements facility 2, is
implemented with alternatives, avoiding runtime checks.
Note that __kernel_getrandom() is implemented without the vdso user
wrapper which would setup a stack frame for odd cases (aka very old
glibc variants) where the caller has not done that. All callers of
__kernel_getrandom() are required to setup a stack frame, like the C ABI
requires it.
The vdso testcases vdso_test_getrandom and vdso_test_chacha pass.
Benchmark on a z16:
$ ./vdso_test_getrandom bench-single
vdso: 25000000 times in 0.493703559 seconds
syscall: 25000000 times in 6.584025337 seconds
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
