[PATCH v2 3/8] arm64: alternatives: proton-pack: prepare for cap changes

Mark Rutland mark.rutland at arm.com
Mon Sep 12 09:22:05 PDT 2022


The spectre patching callbacks use cpus_have_final_cap(), and subsequent
patches will make it invalid to call cpus_have_final_cap() before
alternatives patching has completed.

In preparation for said change, this patch modifies the spectre patching
callbacks use cpus_have_cap(). This is not subject to patching, and will
dynamically check the cpu_hwcaps array, which is functionally equivalent
to the existing behaviour.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Reviewed-by: Joey Gouly <joey.gouly at arm.com>
Cc: Ard Biesheuvel <ardb at kernel.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: James Morse <james.morse at arm.com>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Will Deacon <will at kernel.org>
---
 arch/arm64/kernel/proton-pack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
index 40be3a7c2c531..8010b2e573fac 100644
--- a/arch/arm64/kernel/proton-pack.c
+++ b/arch/arm64/kernel/proton-pack.c
@@ -586,7 +586,7 @@ void __init spectre_v4_patch_fw_mitigation_enable(struct alt_instr *alt,
 	if (spectre_v4_mitigations_off())
 		return;
 
-	if (cpus_have_final_cap(ARM64_SSBS))
+	if (cpus_have_cap(ARM64_SSBS))
 		return;
 
 	if (spectre_v4_mitigations_dynamic())
-- 
2.30.2




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