Pull RISC-V updates from Palmer Dabbelt:
- Support for runtime detection of the Svnapot extension
- Support for Zicboz when clearing pages
- We've moved to GENERIC_ENTRY
- Support for !MMU on rv32 systems
- The linear region is now mapped via huge pages
- Support for building relocatable kernels
- Support for the hwprobe interface
- Various fixes and cleanups throughout the tree
* tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits)
RISC-V: hwprobe: Explicity check for -1 in vdso init
RISC-V: hwprobe: There can only be one first
riscv: Allow to downgrade paging mode from the command line
dt-bindings: riscv: add sv57 mmu-type
RISC-V: hwprobe: Remove __init on probe_vendor_features()
riscv: Use --emit-relocs in order to move .rela.dyn in init
riscv: Check relocations at compile time
powerpc: Move script to check relocations at compile time in scripts/
riscv: Introduce CONFIG_RELOCATABLE
riscv: Move .rela.dyn outside of init to avoid empty relocations
riscv: Prepare EFI header for relocatable kernels
riscv: Unconditionnally select KASAN_VMALLOC if KASAN
riscv: Fix ptdump when KASAN is enabled
riscv: Fix EFI stub usage of KASAN instrumented strcmp function
riscv: Move DTB_EARLY_BASE_VA to the kernel address space
riscv: Rework kasan population functions
riscv: Split early and final KASAN population functions
riscv: Use PUD/P4D/PGD pages for the linear mapping
riscv: Move the linear mapping creation in its own function
riscv: Get rid of riscv_pfn_base variable
...
Add a vDSO function __vdso_riscv_hwprobe, which can sit in front of the
riscv_hwprobe syscall and answer common queries. We stash a copy of
static answers for the "all CPUs" case in the vDSO data page. This data
is private to the vDSO, so we can decide later to change what's stored
there or under what conditions we defer to the syscall. Currently all
data can be discovered at boot, so the vDSO function answers all queries
when the cpumask is set to the "all CPUs" hint.
There's also a boolean in the data that lets the vDSO function know that
all CPUs are the same. In that case, the vDSO will also answer queries
for arbitrary CPU masks in addition to the "all CPUs" hint.
Signed-off-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-7-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
There is no vgettimeofday supported in rv32 that makes simple to
generate rv32 vdso code which only needs riscv64 compiler. Other
architectures need change compiler or -m (machine parameter) to
support vdso32 compiling. If rv32 support vgettimeofday (which
cause C compile) in future, we would add CROSS_COMPILE to support
that makes more requirement on compiler enviornment.
linux-rv64/arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg:
file format elf64-littleriscv
Disassembly of section .text:
0000000000000800 <__vdso_rt_sigreturn>:
800: 08b00893 li a7,139
804: 00000073 ecall
808: 0000 unimp
...
000000000000080c <__vdso_getcpu>:
80c: 0a800893 li a7,168
810: 00000073 ecall
814: 8082 ret
...
0000000000000818 <__vdso_flush_icache>:
818: 10300893 li a7,259
81c: 00000073 ecall
820: 8082 ret
linux-rv32/arch/riscv/kernel/vdso/vdso.so.dbg:
file format elf32-littleriscv
Disassembly of section .text:
00000800 <__vdso_rt_sigreturn>:
800: 08b00893 li a7,139
804: 00000073 ecall
808: 0000 unimp
...
0000080c <__vdso_getcpu>:
80c: 0a800893 li a7,168
810: 00000073 ecall
814: 8082 ret
...
00000818 <__vdso_flush_icache>:
818: 10300893 li a7,259
81c: 00000073 ecall
820: 8082 ret
Finally, reuse all *.S from vdso in compat_vdso that makes
implementation clear and readable.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20220405071314.3225832-17-guoren@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
