diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2022-06-27 22:21:17 +0000 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-06-29 17:43:41 +0200 |
| commit | f43b9876e857c739d407bc56df288b0ebe1a9164 (patch) | |
| tree | 22fcf2716b615556869c460a71ed3fd9b1393bd6 /arch/x86/include/asm/nospec-branch.h | |
| parent | 26aae8ccbc1972233afd08fb3f368947c0314265 (diff) | |
| download | linux-f43b9876e857c739d407bc56df288b0ebe1a9164.tar.bz2 | |
x86/retbleed: Add fine grained Kconfig knobs
Do fine-grained Kconfig for all the various retbleed parts.
NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'arch/x86/include/asm/nospec-branch.h')
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index ccde87e6eabb..bb05ed4f46bd 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -127,6 +127,12 @@ .Lskip_rsb_\@: .endm +#ifdef CONFIG_CPU_UNRET_ENTRY +#define CALL_ZEN_UNTRAIN_RET "call zen_untrain_ret" +#else +#define CALL_ZEN_UNTRAIN_RET "" +#endif + /* * Mitigate RETBleed for AMD/Hygon Zen uarch. Requires KERNEL CR3 because the * return thunk isn't mapped into the userspace tables (then again, AMD @@ -139,10 +145,10 @@ * where we have a stack but before any RET instruction. */ .macro UNTRAIN_RET -#ifdef CONFIG_RETPOLINE +#if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY) ANNOTATE_UNRET_END ALTERNATIVE_2 "", \ - "call zen_untrain_ret", X86_FEATURE_UNRET, \ + CALL_ZEN_UNTRAIN_RET, X86_FEATURE_UNRET, \ "call entry_ibpb", X86_FEATURE_ENTRY_IBPB #endif .endm |