* [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl()
@ 2025-04-01 14:17 Wentao Liang
2025-04-01 15:43 ` Liang, Kan
2025-04-01 18:24 ` Ingo Molnar
0 siblings, 2 replies; 3+ messages in thread
From: Wentao Liang @ 2025-04-01 14:17 UTC (permalink / raw)
To: peterz, mingo, acme, namhyung, mark.rutland, alexander.shishkin,
jolsa, irogers, adrian.hunter, kan.liang, tglx, bp, dave.hansen,
x86, hpa
Cc: linux-perf-users, linux-kernel, Wentao Liang, stable
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@vger.kernel.org # v6.3+
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl()
2025-04-01 14:17 [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl() Wentao Liang
@ 2025-04-01 15:43 ` Liang, Kan
2025-04-01 18:24 ` Ingo Molnar
1 sibling, 0 replies; 3+ messages in thread
From: Liang, Kan @ 2025-04-01 15:43 UTC (permalink / raw)
To: Wentao Liang, peterz, mingo, acme, namhyung, mark.rutland,
alexander.shishkin, jolsa, irogers, adrian.hunter, tglx, bp,
dave.hansen, x86, hpa
Cc: linux-perf-users, linux-kernel, stable
On 2025-04-01 10:17 a.m., Wentao Liang wrote:
> 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@vger.kernel.org # v6.3+
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Thanks,
Kan> ---
> 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 = {
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl()
2025-04-01 14:17 [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl() Wentao Liang
2025-04-01 15:43 ` Liang, Kan
@ 2025-04-01 18:24 ` Ingo Molnar
1 sibling, 0 replies; 3+ messages in thread
From: Ingo Molnar @ 2025-04-01 18:24 UTC (permalink / raw)
To: Wentao Liang
Cc: peterz, mingo, acme, namhyung, mark.rutland, alexander.shishkin,
jolsa, irogers, adrian.hunter, kan.liang, tglx, bp, dave.hansen,
x86, hpa, linux-perf-users, linux-kernel, stable
* Wentao Liang <vulab@iscas.ac.cn> wrote:
> 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@vger.kernel.org # v6.3+
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
> 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);
Exactly what happens without this patch, do we crash during boot due to
the incorrect wrmsr()?
Thanks,
Ingo
^ permalink raw reply [flat|nested] 3+ messages in thread
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2025-04-01 14:17 [PATCH] perf/x86/intel/uncore: Add error handling for uncore_msr_box_ctl() Wentao Liang
2025-04-01 15:43 ` Liang, Kan
2025-04-01 18:24 ` Ingo Molnar
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