diff options
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index dc75195760ca..100a32044385 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -82,6 +82,9 @@ static void __init l1d_flush_select_mitigation(void); static void __init srso_select_mitigation(void); static void __init gds_select_mitigation(void); static void __init gds_apply_mitigation(void); +static void __init bhi_select_mitigation(void); +static void __init bhi_update_mitigation(void); +static void __init bhi_apply_mitigation(void); /* The base value of the SPEC_CTRL MSR without task-specific bits set */ u64 x86_spec_ctrl_base; @@ -208,6 +211,7 @@ void __init cpu_select_mitigations(void) */ srso_select_mitigation(); gds_select_mitigation(); + bhi_select_mitigation(); /* * After mitigations are selected, some may need to update their @@ -225,6 +229,7 @@ void __init cpu_select_mitigations(void) taa_update_mitigation(); mmio_update_mitigation(); rfds_update_mitigation(); + bhi_update_mitigation(); spectre_v1_apply_mitigation(); retbleed_apply_mitigation(); @@ -235,6 +240,7 @@ void __init cpu_select_mitigations(void) rfds_apply_mitigation(); srbds_apply_mitigation(); gds_apply_mitigation(); + bhi_apply_mitigation(); } /* @@ -1794,12 +1800,13 @@ static bool __init spec_ctrl_bhi_dis(void) enum bhi_mitigations { BHI_MITIGATION_OFF, + BHI_MITIGATION_AUTO, BHI_MITIGATION_ON, BHI_MITIGATION_VMEXIT_ONLY, }; static enum bhi_mitigations bhi_mitigation __ro_after_init = - IS_ENABLED(CONFIG_MITIGATION_SPECTRE_BHI) ? BHI_MITIGATION_ON : BHI_MITIGATION_OFF; + IS_ENABLED(CONFIG_MITIGATION_SPECTRE_BHI) ? BHI_MITIGATION_AUTO : BHI_MITIGATION_OFF; static int __init spectre_bhi_parse_cmdline(char *str) { @@ -1821,6 +1828,25 @@ early_param("spectre_bhi", spectre_bhi_parse_cmdline); static void __init bhi_select_mitigation(void) { + if (!boot_cpu_has(X86_BUG_BHI) || cpu_mitigations_off()) + bhi_mitigation = BHI_MITIGATION_OFF; + + if (bhi_mitigation == BHI_MITIGATION_AUTO) + bhi_mitigation = BHI_MITIGATION_ON; +} + +static void __init bhi_update_mitigation(void) +{ + if (spectre_v2_cmd == SPECTRE_V2_CMD_NONE) + bhi_mitigation = BHI_MITIGATION_OFF; + + if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2) && + spectre_v2_cmd == SPECTRE_V2_CMD_AUTO) + bhi_mitigation = BHI_MITIGATION_OFF; +} + +static void __init bhi_apply_mitigation(void) +{ if (bhi_mitigation == BHI_MITIGATION_OFF) return; @@ -1961,9 +1987,6 @@ static void __init spectre_v2_select_mitigation(void) mode == SPECTRE_V2_RETPOLINE) spec_ctrl_disable_kernel_rrsba(); - if (boot_cpu_has(X86_BUG_BHI)) - bhi_select_mitigation(); - spectre_v2_enabled = mode; pr_info("%s\n", spectre_v2_strings[mode]); |