This is a note to let you know that I've just added the patch titled
s390/perf: fix bug when creating per-thread event
to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-perf-fix-bug-when-creating-per-thread-event.patch
and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From fc3100d64f0ae383ae8d845989103da06d62763b Mon Sep 17 00:00:00 2001
From: Pu Hou <bjhoupu@xxxxxxxxxxxxxxxxxx>
Date: Tue, 5 Sep 2017 05:17:24 +0200
Subject: s390/perf: fix bug when creating per-thread event
From: Pu Hou <bjhoupu@xxxxxxxxxxxxxxxxxx>
commit fc3100d64f0ae383ae8d845989103da06d62763b upstream.
A per-thread event could not be created correctly like below:
perf record --per-thread -e rB0000 -- sleep 1
Error:
The sys_perf_event_open() syscall returned with 19 (No such device) for event (rB0000).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
This bug was introduced by:
commit c311c797998c1e70eade463dd60b843da4f1a203
Author: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Date: Mon May 8 15:56:15 2017 -0700
cpumask: make "nr_cpumask_bits" unsigned
If a per-thread event is not attached to any CPU, the cpu field
in struct perf_event is -1. The above commit converts the CPU number
to unsigned int, which result in an illegal CPU number.
Fixes: c311c797998c ("cpumask: make "nr_cpumask_bits" unsigned")
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Acked-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Pu Hou <bjhoupu@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/s390/kernel/perf_cpum_sf.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -823,9 +823,12 @@ static int cpumsf_pmu_event_init(struct
}
/* Check online status of the CPU to which the event is pinned */
- if ((unsigned int)event->cpu >= nr_cpumask_bits ||
- (event->cpu >= 0 && !cpu_online(event->cpu)))
- return -ENODEV;
+ if (event->cpu >= 0) {
+ if ((unsigned int)event->cpu >= nr_cpumask_bits)
+ return -ENODEV;
+ if (!cpu_online(event->cpu))
+ return -ENODEV;
+ }
/* Force reset of idle/hv excludes regardless of what the
* user requested.
Patches currently in stable-queue which might be from bjhoupu@xxxxxxxxxxxxxxxxxx are
queue-4.13/s390-perf-fix-bug-when-creating-per-thread-event.patch