diff options
| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2022-06-15 01:07:19 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-06-27 11:34:00 +0300 |
| commit | 0fe4aeea9c01baabecc8c3afc7889c809d939bc2 (patch) | |
| tree | 7b2532b4d57abff89e5fd5203ee8743df6dd3aea | |
| parent | 3ebc170068885b6fc7bedda6c667bb2c4d533159 (diff) | |
| download | linux-0fe4aeea9c01baabecc8c3afc7889c809d939bc2.tar.xz | |
x86/bugs: Do IBPB fallback check only once
When booting with retbleed=auto, if the kernel wasn't built with
CONFIG_CC_HAS_RETURN_THUNK, the mitigation falls back to IBPB. Make
sure a warning is printed in that case. The IBPB fallback check is done
twice, but it really only needs to be done once.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 15 |
1 files changed, 5 insertions, 10 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 04077d13b3ae..108bd74289c5 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -891,18 +891,13 @@ static void __init retbleed_select_mitigation(void) case RETBLEED_CMD_AUTO: default: if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || - boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) { - - if (IS_ENABLED(CONFIG_RETPOLINE) && - IS_ENABLED(CONFIG_CC_HAS_RETURN_THUNK)) - retbleed_mitigation = RETBLEED_MITIGATION_UNRET; - else - retbleed_mitigation = RETBLEED_MITIGATION_IBPB; - } + boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) + retbleed_mitigation = RETBLEED_MITIGATION_UNRET; /* - * The Intel mitigation (IBRS) was already selected in - * spectre_v2_select_mitigation(). + * The Intel mitigation (IBRS or eIBRS) was already selected in + * spectre_v2_select_mitigation(). 'retbleed_mitigation' will + * be set accordingly below. */ break; |