The following commit has been merged into the x86/bugs branch of tip:
Commit-ID: 530e80648bff083e1d19ad7248c0540812a9a35f
Gitweb: https://git.kernel.org/tip/530e80648bff083e1d19ad7248c0540812a9a35f
Author: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
AuthorDate: Wed, 11 Jun 2025 10:29:15 -07:00
Committer: Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Mon, 23 Jun 2025 12:16:30 +02:00
x86/bugs: Simplify the retbleed=stuff checks
Simplify the nested checks, remove redundant print and comment.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250611-eibrs-fix-v4-2-5ff86cac6c61@linux.intel.com
---
arch/x86/kernel/cpu/bugs.c | 24 ++++++++----------------
1 file changed, 8 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 53649df..94d0de3 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1263,24 +1263,16 @@ static void __init retbleed_update_mitigation(void)
if (!boot_cpu_has_bug(X86_BUG_RETBLEED) || cpu_mitigations_off())
return;
- /*
- * retbleed=stuff is only allowed on Intel. If stuffing can't be used
- * then a different mitigation will be selected below.
- *
- * its=stuff will also attempt to enable stuffing.
- */
- if (retbleed_mitigation == RETBLEED_MITIGATION_STUFF ||
- its_mitigation == ITS_MITIGATION_RETPOLINE_STUFF) {
- if (spectre_v2_enabled != SPECTRE_V2_RETPOLINE) {
- pr_err("WARNING: retbleed=stuff depends on spectre_v2=retpoline\n");
- retbleed_mitigation = RETBLEED_MITIGATION_NONE;
- } else {
- if (retbleed_mitigation != RETBLEED_MITIGATION_STUFF)
- pr_info("Retbleed mitigation updated to stuffing\n");
+ /* ITS can also enable stuffing */
+ if (its_mitigation == ITS_MITIGATION_RETPOLINE_STUFF)
+ retbleed_mitigation = RETBLEED_MITIGATION_STUFF;
- retbleed_mitigation = RETBLEED_MITIGATION_STUFF;
- }
+ if (retbleed_mitigation == RETBLEED_MITIGATION_STUFF &&
+ spectre_v2_enabled != SPECTRE_V2_RETPOLINE) {
+ pr_err("WARNING: retbleed=stuff depends on spectre_v2=retpoline\n");
+ retbleed_mitigation = RETBLEED_MITIGATION_NONE;
}
+
/*
* Let IBRS trump all on Intel without affecting the effects of the
* retbleed= cmdline option except for call depth based stuffing