kernel/arch/riscv/include/asm/vdso.h, branch linux-rolling-stable

riscv: Replace ASSEMBLY with ASSEMBLER in non-uapi headers

2025-09-16T22:25:30Z

While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize on the __ASSEMBLER__ macro that is provided by the compilers now. This originally was a completely mechanical patch (done with a simple "sed -i" statement), with some manual fixups during rebasing of the patch later. Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Alexandre Ghiti Cc: linux-riscv@lists.infradead.org Signed-off-by: Thomas Huth Link: https://lore.kernel.org/r/20250606070952.498274-3-thuth@redhat.com Signed-off-by: Paul Walmsley

riscv: vdso: Switch to generic storage implementation

2025-02-21T08:54:02Z

The generic storage implementation provides the same features as the custom one. However it can be shared between architectures, making maintenance easier. Co-developed-by: Nam Cao Signed-off-by: Nam Cao Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-9-13a4669dfc8c@linutronix.de

riscv: alternative: patch alternatives in the vDSO

2023-02-01T07:29:42Z

Make it possible to use alternatives in the vDSO, so that better implementations can be used if possible. Signed-off-by: Jisheng Zhang Reviewed-by: Guo Ren Reviewed-by: Andrew Jones Link: https://lore.kernel.org/r/20230128172856.3814-11-jszhang@kernel.org Signed-off-by: Palmer Dabbelt

riscv/vdso: typo therefor

2022-10-26T06:29:36Z

The adverbs 'therefor' and 'therefore' have different meaning. As the meaning here is 'consequently' the spelling should be 'therefore'. Signed-off-by: Heinrich Schuchardt Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20220925004757.9089-1-heinrich.schuchardt@canonical.com Signed-off-by: Palmer Dabbelt

riscv: compat: vdso: Add COMPAT_VDSO base code implementation

2022-04-26T20:36:53Z

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 Signed-off-by: Guo Ren Tested-by: Heiko Stuebner Link: https://lore.kernel.org/r/20220405071314.3225832-17-guoren@kernel.org Signed-off-by: Palmer Dabbelt

riscv/vdso: Drop unneeded part due to merge issue

2021-10-26T22:49:41Z

It seems that something is wrong when patch "riscv/vdso: Refactor asm/vdso.h" is merged. Let's fix the merge issue. Fixes: 8edab02386c3 ("Merge remote-tracking branch 'palmer/riscv-vdso-cleanup' into for-next") Signed-off-by: Kefeng Wang Signed-off-by: Palmer Dabbelt

riscv/vdso: Add support for time namespaces

2021-10-04T21:16:43Z

Implement generic vdso time namespace support which also enables time namespaces for riscv. This is quite similar to what arm64 does. selftest/timens test result: 1..10 ok 1 Passed for CLOCK_BOOTTIME (syscall) ok 2 Passed for CLOCK_BOOTTIME (vdso) ok 3 # SKIP CLOCK_BOOTTIME_ALARM isn't supported ok 4 # SKIP CLOCK_BOOTTIME_ALARM isn't supported ok 5 Passed for CLOCK_MONOTONIC (syscall) ok 6 Passed for CLOCK_MONOTONIC (vdso) ok 7 Passed for CLOCK_MONOTONIC_COARSE (syscall) ok 8 Passed for CLOCK_MONOTONIC_COARSE (vdso) ok 9 Passed for CLOCK_MONOTONIC_RAW (syscall) ok 10 Passed for CLOCK_MONOTONIC_RAW (vdso) # Totals: pass:8 fail:0 xfail:0 xpass:0 skip:2 error:0 Signed-off-by: Tong Tiangen Signed-off-by: Palmer Dabbelt

riscv/vdso: Move vdso data page up front

2021-10-02T20:42:25Z

As commit 601255ae3c98 ("arm64: vdso: move data page before code pages"), the same issue exists on riscv, testcase is shown below, make sure that vdso.so is bigger than page size, struct timespec tp; clock_gettime(5, &tp); printf("tv_sec: %ld, tv_nsec: %ld\n", tp.tv_sec, tp.tv_nsec); without this patch, test result : tv_sec: 0, tv_nsec: 0 with this patch, test result : tv_sec: 1629271537, tv_nsec: 748000000 Move the vdso data page in front of the VDSO area to fix the issue. Fixes: ad5d1122b82fb ("riscv: use vDSO common flow to reduce the latency of the time-related functions") Signed-off-by: Tong Tiangen Reviewed-by: Kefeng Wang Signed-off-by: Palmer Dabbelt

riscv/vdso: Refactor asm/vdso.h

2021-10-02T20:42:23Z

The asm/vdso.h will be included in vdso.lds.S in the next patch, the following cleanup is needed to avoid syntax error: 1.the declaration of sys_riscv_flush_icache() is moved into asm/syscall.h. 2.the definition of struct vdso_data is moved into kernel/vdso.c. 2.the definition of VDSO_SYMBOL is placed under "#ifndef __ASSEMBLY__". Also remove the redundant linux/types.h include. Signed-off-by: Tong Tiangen Reviewed-by: Kefeng Wang Signed-off-by: Palmer Dabbelt

RISC-V: Fix VDSO build for !MMU

2021-08-26T05:58:30Z

We don't have a VDSO for the !MMU configurations, so don't try to build one. Fixes: fde9c59aebaf ("riscv: explicitly use symbol offsets for VDSO") Signed-off-by: Palmer Dabbelt