On 2024-04-05 16:14, Suren Baghdasaryan wrote:
On Fri, Apr 5, 2024 at 6:37 AM Klara Modin <klarasmodin@xxxxxxxxx> wrote:
If I enable this, I consistently get percpu allocation failures. I can
occasionally reproduce it in qemu. I've attached the logs and my config,
please let me know if there's anything else that could be relevant.
Thanks for the report!
In debug_alloc_profiling.log I see:
[ 7.445127] percpu: limit reached, disable warning
That's probably the reason. I'll take a closer look at the cause of
that and how we can fix it.
Thanks!
In qemu-alloc3.log I see couple of warnings:
[ 1.111620] alloc_tag was not set
[ 1.111880] WARNING: CPU: 0 PID: 164 at
include/linux/alloc_tag.h:118 kfree (./include/linux/alloc_tag.h:118
(discriminator 1) ./include/linux/alloc_tag.h:161 (discriminator 1)
mm/slub.c:2043 ...
[ 1.161710] alloc_tag was not cleared (got tag for fs/squashfs/cache.c:413)
[ 1.162289] WARNING: CPU: 0 PID: 195 at
include/linux/alloc_tag.h:109 kmalloc_trace_noprof
(./include/linux/alloc_tag.h:109 (discriminator 1)
./include/linux/alloc_tag.h:149 (discriminator 1) ...
Which means we missed to instrument some allocation. Can you please
check if disabling CONFIG_MEM_ALLOC_PROFILING_DEBUG fixes QEMU case?
In the meantime I'll try to reproduce and fix this.
Thanks,
Suren.
That does seem to be the case from what I can tell. I didn't get the
warning in qemu consistently, but it hasn't reappeared for a number of
times at least with the debugging option off.
Regards,
Klara Modin
