On Mon, Mar 16, 2020 at 01:59:49PM +0100, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f967140dfb7442e2db0868b03b961f9c59418a1b Mon Sep 17 00:00:00 2001
From: Kim Phillips <kim.phillips@xxxxxxx>
Date: Wed, 11 Mar 2020 14:13:21 -0500
Subject: [PATCH] perf/amd/uncore: Replace manual sampling check with
CAP_NO_INTERRUPT flag
Enable the sampling check in kernel/events/core.c::perf_event_open(),
which returns the more appropriate -EOPNOTSUPP.
BEFORE:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (l3_request_g1.caching_l3_cache_accesses).
/bin/dmesg | grep -i perf may provide additional information.
With nothing relevant in dmesg.
AFTER:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
l3_request_g1.caching_l3_cache_accesses: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
Fixes: c43ca5091a37 ("perf/x86/amd: Add support for AMD NB and L2I "uncore" counters")
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Acked-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20200311191323.13124-1-kim.phillips@xxxxxxx
I've worked around not having PERF_PMU_CAP_NO_EXCLUDE on older kernels
and queued this patch for 4.19-4.4.
--
Thanks,
Sasha
