x86/mtrr: Check if fixed MTRRs exist before saving them
PATCH v2 1/1 x86/mtrr: Check if fixed MTRRs exist before saving them
This one place forgot to check the fixed capability. Otherwise there will a harmless but ugly WARN_ON for the failed WRMSR when the MSR doesn't exist. Noticed when testing X86S support.
---
v2: Add Fixes tag and expand description.
--- arch/x86/kernel/cpu/mtrr/mtrr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
arch/x86/kernel/cpu/mtrr/mtrr.c +1 -1
@@ -609,7 +609,7 @@ void mtrr_save_state(void) {int first_cpu; -if (!mtrr_enabled ()) +if (!mtrr_enabled () || !mtrr_state.have_fixed)return ; first_cpu =cpumask_first (cpu_online_mask);
Signature · 1 line
2.43.0
Quoted 10 lines · Andi Kleen
This one place forgot to check the fixed capability. Otherwise there will a harmless but ugly
WARN_ONfor the failed WRMSR when the MSR doesn't exist. Noticed when testing X86S support.Fixes 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before")Signed-off-by Andi Kleen <[email protected]>---
v2: Add Fixes tag and expand description.
Just wanted to ping the patch. Thanks.
-Andi
Quoted 20 lines
--- arch/x86/kernel/cpu/mtrr/mtrr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)arch/x86/kernel/cpu/mtrr/mtrr.c +1
-1@@ -609,7 +609,7 @@ void mtrr_save_state(void) {int first_cpu; -if (!mtrr_enabled ()) +if (!mtrr_enabled () || !mtrr_state.have_fixed)return ; first_cpu =cpumask_first (cpu_online_mask);Signature · 1 line
2.43.0
Quoted 1 line · Andi Kleen
This one place forgot to check the fixed capability.
This one place forgot? And what the heck is a fixed capability?
Quoted 2 lines
Otherwise there will a harmless but ugly
WARN_ONfor the failed WRMSR when the MSR doesn't exist.
This is not a sentence as it lacks a verb,
Also it does not matter whether you think that the WARN_ON() is ugly or not. Can you please write a changelog in technical terms?
Quoted 1 line
Noticed when testing X86S support.
Who cares?
Quoted 1 line
Fixes 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before")
This fixes tag is pointlessly truncated. The correct one is:
It's not rocket science to copy & pasta correctly.
Thanks,
tglx