diff options
| author | Nathan Chancellor <nathan@kernel.org> | 2026-01-23 16:20:28 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2026-01-24 10:18:28 +0100 |
| commit | 3e30278e0c71808e156cac8da5895d636ce819d5 (patch) | |
| tree | fbc4252c5639fa99c3a10d7f89162fc163c9c045 | |
| parent | 436ee609df7da5671ae5a717d1df867313868baf (diff) | |
x86/entry/vdso32: Omit '.cfi_offset eflags' for LLVM < 16
After commit:
884961618ee5 ("x86/entry/vdso32: Remove open-coded DWARF in sigreturn.S")
building arch/x86/entry/vdso/vdso32/sigreturn.S with LLVM 15 fails with:
<instantiation>:18:20: error: invalid register name
.cfi_offset eflags, 64
^
arch/x86/entry/vdso/vdso32/sigreturn.S:33:2: note: while in macro instantiation
STARTPROC_SIGNAL_FRAME 8
^
Support for eflags as an argument to .cfi_offset was added in the LLVM
16 development cycle:
https://github.com/llvm/llvm-project/commit/67bd3c58c0c7389e39c5a2f4d3b1a30459ccf5b7 [1]
Only add this .cfi_offset directive if it is supported by the assembler
to clear up the error.
[ mingo: Tidied up the changelog and the comment a bit ]
Fixes: 884961618ee5 ("x86/entry/vdso32: Remove open-coded DWARF in sigreturn.S")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Link: https://patch.msgid.link/20260123-x86-vdso32-wa-llvm-15-cfi-offset-eflags-v1-1-0f412e3516a4@kernel.org
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/sigreturn.S | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/entry/vdso/vdso32/sigreturn.S b/arch/x86/entry/vdso/vdso32/sigreturn.S index 25b0ac4b4bfe..b433353bc8e3 100644 --- a/arch/x86/entry/vdso/vdso32/sigreturn.S +++ b/arch/x86/entry/vdso/vdso32/sigreturn.S @@ -22,7 +22,17 @@ CFI_OFFSET cs, IA32_SIGCONTEXT_cs CFI_OFFSET ss, IA32_SIGCONTEXT_ss CFI_OFFSET ds, IA32_SIGCONTEXT_ds +/* + * .cfi_offset eflags requires LLVM 16 or newer: + * + * https://github.com/llvm/llvm-project/commit/67bd3c58c0c7389e39c5a2f4d3b1a30459ccf5b7 + * + * Check for 16.0.1 to ensure the support is present, as 16.0.0 may be a + * prerelease version. + */ +#if defined(CONFIG_AS_IS_GNU) || (defined(CONFIG_AS_IS_LLVM) && CONFIG_AS_VERSION >= 160001) CFI_OFFSET eflags, IA32_SIGCONTEXT_flags +#endif .endm .text |