From 2a08b832712980b9eb0e913d64a42c74fc56319b Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 31 Oct 2024 04:06:16 -0700 Subject: [PATCH] x86/bugs: Use the cpu_smt_possible() helper instead of open-coded code There is a helper function to check if SMT is available. Use this helper instead of performing the check manually. The helper function cpu_smt_possible() does exactly the same thing as was being done manually inside spectre_v2_user_select_mitigation(). Specifically, it returns false if CONFIG_SMP is disabled, otherwise it checks the cpu_smt_control global variable. This change improves code consistency and reduces duplication. No change in functionality intended. Signed-off-by: Breno Leitao Signed-off-by: Ingo Molnar Reviewed-by: Pawan Gupta Cc: David Kaplan Link: https://lore.kernel.org/r/20241031-x86_bugs_last_v2-v2-1-b7ff1dab840e@debian.org --- arch/x86/kernel/cpu/bugs.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 93c437f44c24..346bebff3f6c 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1346,16 +1346,11 @@ static void __init spectre_v2_user_select_mitigation(void) { enum spectre_v2_user_mitigation mode = SPECTRE_V2_USER_NONE; - bool smt_possible = IS_ENABLED(CONFIG_SMP); enum spectre_v2_user_cmd cmd; if (!boot_cpu_has(X86_FEATURE_IBPB) && !boot_cpu_has(X86_FEATURE_STIBP)) return; - if (cpu_smt_control == CPU_SMT_FORCE_DISABLED || - cpu_smt_control == CPU_SMT_NOT_SUPPORTED) - smt_possible = false; - cmd = spectre_v2_parse_user_cmdline(); switch (cmd) { case SPECTRE_V2_USER_CMD_NONE: @@ -1416,7 +1411,7 @@ spectre_v2_user_select_mitigation(void) * so allow for STIBP to be selected in those cases. */ if (!boot_cpu_has(X86_FEATURE_STIBP) || - !smt_possible || + !cpu_smt_possible() || (spectre_v2_in_eibrs_mode(spectre_v2_enabled) && !boot_cpu_has(X86_FEATURE_AUTOIBRS))) return;