[PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl()
From: Wentao Liang
Date: Tue Apr 01 2025 - 10:19:42 EST
In mtl_uncore_msr_init_box(), the return value of uncore_msr_box_ctl()
needs to be checked before being used as the parameter of wrmsrl().
A proper implementation can be found in ivbep_uncore_msr_init_box().
Add error handling for uncore_msr_box_ctl() to ensure the MSR write
operation is only performed when a valid MSR address is returned.
Fixes: c828441f21dd ("perf/x86/intel/uncore: Add Meteor Lake support")
Cc: stable@xxxxxxxxxxxxxxx # v6.3+
Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
---
arch/x86/events/intel/uncore_snb.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/x86/events/intel/uncore_snb.c b/arch/x86/events/intel/uncore_snb.c
index 3934e1e4e3b1..84070388f495 100644
--- a/arch/x86/events/intel/uncore_snb.c
+++ b/arch/x86/events/intel/uncore_snb.c
@@ -691,7 +691,10 @@ static struct intel_uncore_type mtl_uncore_hac_cbox = {
static void mtl_uncore_msr_init_box(struct intel_uncore_box *box)
{
- wrmsrl(uncore_msr_box_ctl(box), SNB_UNC_GLOBAL_CTL_EN);
+ unsigned int msr = uncore_msr_box_ctl(box);
+
+ if (msr)
+ wrmsrl(msr, SNB_UNC_GLOBAL_CTL_EN);
}
static struct intel_uncore_ops mtl_uncore_msr_ops = {
--
2.42.0.windows.2