From: Michal Hocko <mhocko@suse.com>
To: Barry Song <21cnbao@gmail.com>
Cc: akpm@linux-foundation.org, linux-mm@kvack.org,
Barry Song <v-songbaohua@oppo.com>,
Uladzislau Rezki <urezki@gmail.com>,
Christoph Hellwig <hch@infradead.org>,
Lorenzo Stoakes <lstoakes@gmail.com>,
Christoph Lameter <cl@linux.com>,
Pekka Enberg <penberg@kernel.org>,
David Rientjes <rientjes@google.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Vlastimil Babka <vbabka@suse.cz>,
Roman Gushchin <roman.gushchin@linux.dev>,
Hyeonggon Yoo <42.hyeyoo@gmail.com>
Subject: Re: [PATCH RFC] mm: warn potential return NULL for kmalloc_array and kvmalloc_array with __GFP_NOFAIL
Date: Fri, 19 Jul 2024 10:01:09 +0200 [thread overview]
Message-ID: <ZpodRShdeVsFu_mH@tiehlicka> (raw)
In-Reply-To: <CAGsJ_4xpLf6qfvfNmowT01xF8ETBPM46-A=3umHEUXpk=fQ04A@mail.gmail.com>
On Fri 19-07-24 19:51:06, Barry Song wrote:
> On Fri, Jul 19, 2024 at 7:42 PM Michal Hocko <mhocko@suse.com> wrote:
[...]
> > It cannot reclaim itself and it cannot sleep to wait for the memory so
> > NOFAIL semantic is simply impossible. We have put a warning in place to
>
> this is still "right" behaviour to retry infinitely at least according
> to the doc of
> __GFP_NOFAIL.
I do not agree that implementing busy loop in the kernel is the right
practice!
> I assume getting new memory by many retries is still
> possibly some other processes might be reclaiming or freeing memory
> then providing free memory to this one being stuck.
No, I strongly disagree we should even pretend this is a supported
allocation strategy. NAK to any attempt to legalize it in some form.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2024-07-19 8:01 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-17 23:00 Barry Song
2024-07-18 6:58 ` Michal Hocko
2024-07-18 7:04 ` Christoph Hellwig
2024-07-18 7:12 ` Michal Hocko
2024-07-18 8:16 ` Vlastimil Babka
2024-07-18 7:22 ` Barry Song
2024-07-18 7:27 ` Michal Hocko
2024-07-18 7:41 ` Barry Song
2024-07-18 7:53 ` Michal Hocko
2024-07-18 8:18 ` Barry Song
2024-07-18 8:32 ` Michal Hocko
2024-07-18 8:43 ` Barry Song
2024-07-18 8:50 ` Michal Hocko
2024-07-19 0:35 ` Barry Song
2024-07-19 7:02 ` Michal Hocko
2024-07-19 7:07 ` Barry Song
2024-07-19 7:42 ` Michal Hocko
2024-07-19 7:51 ` Barry Song
2024-07-19 8:01 ` Michal Hocko [this message]
2024-07-19 8:28 ` Barry Song
2024-07-19 8:40 ` Michal Hocko
2024-07-19 9:36 ` Barry Song
2024-07-19 9:45 ` Michal Hocko
2024-07-19 9:58 ` Barry Song
2024-07-19 10:57 ` Michal Hocko
2024-07-19 11:05 ` Barry Song
2024-07-19 11:19 ` Michal Hocko
2024-07-19 8:50 ` Vlastimil Babka
2024-07-19 9:33 ` Michal Hocko
2024-07-19 10:10 ` Vlastimil Babka
2024-07-19 10:52 ` Michal Hocko
2024-07-19 11:13 ` Vlastimil Babka
2024-07-19 11:26 ` Michal Hocko
2024-07-19 13:02 ` Barry Song
2024-07-19 13:30 ` Michal Hocko
2024-07-20 0:36 ` Barry Song
2024-07-22 7:23 ` Michal Hocko
2024-07-22 7:34 ` Vlastimil Babka
2024-07-19 7:37 ` Christoph Hellwig
2024-07-19 7:43 ` Barry Song
2024-07-19 7:53 ` Christoph Hellwig
2024-07-20 22:14 ` Barry Song
2024-07-22 7:26 ` Michal Hocko
2024-07-22 8:09 ` Barry Song
2024-07-22 9:01 ` Michal Hocko
2024-07-22 23:18 ` Christoph Hellwig
2024-07-22 23:22 ` Barry Song
2024-07-19 8:35 ` Vlastimil Babka
2024-07-18 7:48 ` Hailong Liu
2024-07-18 8:33 ` Barry Song
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