| Message ID | 20191118034452.9939-1-maddy@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] powerpc/perf: Disable trace_imc pmu | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (3b4852888d3f7e0cde65b29af9c518f4019e145f) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 13 lines checked |
| snowpatch_ozlabs/needsstable | warning | Please consider tagging this patch for stable! |
On 11/18/19 9:14 AM, Madhavan Srinivasan wrote: > When a root user or a user with CAP_SYS_ADMIN > privilege use trace_imc performance monitoring > unit events, to monitor application or KVM threads, > may result in a checkstop (System crash). Reason > being frequent switch of the "trace/accumulation" > mode of In-Memory Collection hardware. > This patch disables trace_imc pmu unit, but will > be re-enabled at a later stage with a fix patchset. > > Fixes: 012ae244845f1 ('powerpc/perf: Trace imc PMU functions') > Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Tested-by: Hariharan T.S. <hari@linux.ibm.com> > --- > Changelog v1: > - Added fixes and signed-off by. > arch/powerpc/platforms/powernv/opal-imc.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c > index e04b20625cb9..5790f078771f 100644 > --- a/arch/powerpc/platforms/powernv/opal-imc.c > +++ b/arch/powerpc/platforms/powernv/opal-imc.c > @@ -285,7 +285,12 @@ static int opal_imc_counters_probe(struct platform_device *pdev) > domain = IMC_DOMAIN_THREAD; > break; > case IMC_TYPE_TRACE: > - domain = IMC_DOMAIN_TRACE; > + /* Using trace_imc events to monitor > + * application or KVM thread performances > + * may result in a checkstop (system crash). > + * So disabling it for now. > + */ > + domain = -1; > break; > default: > pr_warn("IMC Unknown Device type \n"); >
On Mon, 2019-11-18 at 03:44:52 UTC, Madhavan Srinivasan wrote: > When a root user or a user with CAP_SYS_ADMIN > privilege use trace_imc performance monitoring > unit events, to monitor application or KVM threads, > may result in a checkstop (System crash). Reason > being frequent switch of the "trace/accumulation" > mode of In-Memory Collection hardware. > This patch disables trace_imc pmu unit, but will > be re-enabled at a later stage with a fix patchset. > > Fixes: 012ae244845f1 ('powerpc/perf: Trace imc PMU functions') > Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/249fad734a25889a4f23ed014d43634af6798063 cheers
diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index e04b20625cb9..5790f078771f 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c @@ -285,7 +285,12 @@ static int opal_imc_counters_probe(struct platform_device *pdev) domain = IMC_DOMAIN_THREAD; break; case IMC_TYPE_TRACE: - domain = IMC_DOMAIN_TRACE; + /* Using trace_imc events to monitor + * application or KVM thread performances + * may result in a checkstop (system crash). + * So disabling it for now. + */ + domain = -1; break; default: pr_warn("IMC Unknown Device type \n");
When a root user or a user with CAP_SYS_ADMIN privilege use trace_imc performance monitoring unit events, to monitor application or KVM threads, may result in a checkstop (System crash). Reason being frequent switch of the "trace/accumulation" mode of In-Memory Collection hardware. This patch disables trace_imc pmu unit, but will be re-enabled at a later stage with a fix patchset. Fixes: 012ae244845f1 ('powerpc/perf: Trace imc PMU functions') Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> --- Changelog v1: - Added fixes and signed-off by. arch/powerpc/platforms/powernv/opal-imc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)