perf/amd/ibs: Assorted fixes

[PATCH v2 0/5] perf/amd/ibs: Assorted fixes

Posted by Ravi Bangoria 1 month, 2 weeks ago

Address several issues in the AMD IBS perf code: interrupt accounting
for discarded samples, a Zen5-specific quirk, PhyAddrVal handling,
NMI-safety with perf_allow_kernel(), and a race between event add and
NMI.

Patches are prepared on tip/perf/core (7db06e329af3)

v1: https://lore.kernel.org/r/20260116033450.965-1-ravi.bangoria@amd.com
v1->v2:
  - Split fixes series from future enhancements
  - Add interrupt throttling for zero-rip erratum #1197
  - Avoid calling perf_allow_kernel() in NMI context (new patch)

Ravi Bangoria (5):
  perf/amd/ibs: Account interrupt for discarded samples
  perf/amd/ibs: Limit ldlat->l3missonly dependency to Zen5
  perf/amd/ibs: Preserve PhyAddrVal bit when clearing PhyAddr MSR
  perf/amd/ibs: Avoid calling perf_allow_kernel() from the IBS NMI
    handler
  perf/amd/ibs: Avoid race between event add and NMI

 arch/x86/events/amd/ibs.c          | 28 ++++++++++++++++++++++------
 arch/x86/events/perf_event_flags.h |  1 +
 2 files changed, 23 insertions(+), 6 deletions(-)

-- 
2.43.0

Re: [PATCH v2 0/5] perf/amd/ibs: Assorted fixes

Posted by Namhyung Kim 1 month, 1 week ago

Hello Ravi,

On Mon, Feb 16, 2026 at 04:22:11AM +0000, Ravi Bangoria wrote:
> Address several issues in the AMD IBS perf code: interrupt accounting
> for discarded samples, a Zen5-specific quirk, PhyAddrVal handling,
> NMI-safety with perf_allow_kernel(), and a race between event add and
> NMI.
> 
> Patches are prepared on tip/perf/core (7db06e329af3)
> 
> v1: https://lore.kernel.org/r/20260116033450.965-1-ravi.bangoria@amd.com
> v1->v2:
>   - Split fixes series from future enhancements
>   - Add interrupt throttling for zero-rip erratum #1197
>   - Avoid calling perf_allow_kernel() in NMI context (new patch)
> 
> Ravi Bangoria (5):
>   perf/amd/ibs: Account interrupt for discarded samples
>   perf/amd/ibs: Limit ldlat->l3missonly dependency to Zen5
>   perf/amd/ibs: Preserve PhyAddrVal bit when clearing PhyAddr MSR
>   perf/amd/ibs: Avoid calling perf_allow_kernel() from the IBS NMI
>     handler
>   perf/amd/ibs: Avoid race between event add and NMI

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> 
>  arch/x86/events/amd/ibs.c          | 28 ++++++++++++++++++++++------
>  arch/x86/events/perf_event_flags.h |  1 +
>  2 files changed, 23 insertions(+), 6 deletions(-)
> 
> -- 
> 2.43.0
>