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| author | Jim Shu <jim.shu@sifive.com> | 2026-01-25 21:09:56 -0700 |
|---|---|---|
| committer | Paul Walmsley <pjw@kernel.org> | 2026-01-29 02:38:40 -0700 |
| commit | 37f57bd3faeac92e898c3381355f4fd2b6a80901 (patch) | |
| tree | fb5765cebb42c41f24726fcc14309b0a8392eace /arch/riscv/include | |
| parent | 41213bf2ae6c936f51a79986b37f95da9ecbb970 (diff) | |
| download | linux-next-37f57bd3faeac92e898c3381355f4fd2b6a80901.tar.gz linux-next-37f57bd3faeac92e898c3381355f4fd2b6a80901.zip | |
arch/riscv: compile vdso with landing pad and shadow stack note
User mode tasks compiled with Zicfilp may call indirectly into the
vdso (like hwprobe indirect calls). Add support for compiling landing
pads into the vdso. Landing pad instructions in the vdso will be
no-ops for tasks which have not enabled landing pads. Furthermore, add
support for the C sources of the vdso to be compiled with shadow stack
and landing pads enabled as well.
Landing pad and shadow stack instructions are emitted only when the
VDSO_CFI cflags option is defined during compile.
Signed-off-by: Jim Shu <jim.shu@sifive.com>
Reviewed-by: Zong Li <zong.li@sifive.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-v23-23-b55691eacf4f@rivosinc.com
[pjw@kernel.org: cleaned up patch description, issues reported by checkpatch]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Diffstat (limited to 'arch/riscv/include')
| -rw-r--r-- | arch/riscv/include/asm/assembler.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/assembler.h b/arch/riscv/include/asm/assembler.h index 16931712beab..a8df1999118b 100644 --- a/arch/riscv/include/asm/assembler.h +++ b/arch/riscv/include/asm/assembler.h @@ -80,3 +80,47 @@ .endm #endif /* __ASM_ASSEMBLER_H */ + +#if defined(VDSO_CFI) && (__riscv_xlen == 64) +.macro vdso_lpad, label = 0 +lpad \label +.endm +#else +.macro vdso_lpad, label = 0 +.endm +#endif + +/* + * This macro emits a program property note section identifying + * architecture features which require special handling, mainly for + * use in assembly files included in the VDSO. + */ +#define NT_GNU_PROPERTY_TYPE_0 5 +#define GNU_PROPERTY_RISCV_FEATURE_1_AND 0xc0000000 + +#define GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP BIT(0) +#define GNU_PROPERTY_RISCV_FEATURE_1_ZICFISS BIT(1) + +#if defined(VDSO_CFI) && (__riscv_xlen == 64) +#define GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT \ + (GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP | GNU_PROPERTY_RISCV_FEATURE_1_ZICFISS) +#endif + +#ifdef GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT +.macro emit_riscv_feature_1_and, feat = GNU_PROPERTY_RISCV_FEATURE_1_DEFAULT + .pushsection .note.gnu.property, "a" + .p2align 3 + .word 4 + .word 16 + .word NT_GNU_PROPERTY_TYPE_0 + .asciz "GNU" + .word GNU_PROPERTY_RISCV_FEATURE_1_AND + .word 4 + .word \feat + .word 0 + .popsection +.endm +#else +.macro emit_riscv_feature_1_and, feat = 0 +.endm +#endif |