linux-kernel - Re: [PATCH v6 00/37] Memory allocation profiling

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <41328d5a-3e41-4936-bcb7-c0a85e6ce332@gmail.com>
Date: Fri, 5 Apr 2024 16:30:19 +0200
From: Klara Modin <klarasmodin@...il.com>
To: Suren Baghdasaryan <surenb@...gle.com>
Cc: akpm@...ux-foundation.org, kent.overstreet@...ux.dev, mhocko@...e.com,
 vbabka@...e.cz, hannes@...xchg.org, roman.gushchin@...ux.dev,
 mgorman@...e.de, dave@...olabs.net, willy@...radead.org,
 liam.howlett@...cle.com, penguin-kernel@...ove.sakura.ne.jp, corbet@....net,
 void@...ifault.com, peterz@...radead.org, juri.lelli@...hat.com,
 catalin.marinas@....com, will@...nel.org, arnd@...db.de, tglx@...utronix.de,
 mingo@...hat.com, dave.hansen@...ux.intel.com, x86@...nel.org,
 peterx@...hat.com, david@...hat.com, axboe@...nel.dk, mcgrof@...nel.org,
 masahiroy@...nel.org, nathan@...nel.org, dennis@...nel.org,
 jhubbard@...dia.com, tj@...nel.org, muchun.song@...ux.dev, rppt@...nel.org,
 paulmck@...nel.org, pasha.tatashin@...een.com, yosryahmed@...gle.com,
 yuzhao@...gle.com, dhowells@...hat.com, hughd@...gle.com,
 andreyknvl@...il.com, keescook@...omium.org, ndesaulniers@...gle.com,
 vvvvvv@...gle.com, gregkh@...uxfoundation.org, ebiggers@...gle.com,
 ytcoode@...il.com, vincent.guittot@...aro.org, dietmar.eggemann@....com,
 rostedt@...dmis.org, bsegall@...gle.com, bristot@...hat.com,
 vschneid@...hat.com, cl@...ux.com, penberg@...nel.org,
 iamjoonsoo.kim@....com, 42.hyeyoo@...il.com, glider@...gle.com,
 elver@...gle.com, dvyukov@...gle.com, songmuchun@...edance.com,
 jbaron@...mai.com, aliceryhl@...gle.com, rientjes@...gle.com,
 minchan@...gle.com, kaleshsingh@...gle.com, kernel-team@...roid.com,
 linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
 iommu@...ts.linux.dev, linux-arch@...r.kernel.org,
 linux-fsdevel@...r.kernel.org, linux-mm@...ck.org,
 linux-modules@...r.kernel.org, kasan-dev@...glegroups.com,
 cgroups@...r.kernel.org
Subject: Re: [PATCH v6 00/37] Memory allocation profiling

On 2024-04-05 16:14, Suren Baghdasaryan wrote:
> On Fri, Apr 5, 2024 at 6:37 AM Klara Modin <klarasmodin@...il.com> 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