linux-kernel - Re: [PATCH v1] mm/gup: remove (VM_)BUG

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: <f1a3e3c1-103f-46d4-aa0e-ea057e78954d@suse.cz>
Date: Thu, 5 Jun 2025 07:37:58 +0200
From: Vlastimil Babka <vbabka@...e.cz>
To: John Hubbard <jhubbard@...dia.com>, David Hildenbrand <david@...hat.com>,
 linux-kernel@...r.kernel.org
Cc: linux-mm@...ck.org, Andrew Morton <akpm@...ux-foundation.org>,
 Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
 "Liam R. Howlett" <Liam.Howlett@...cle.com>, Mike Rapoport
 <rppt@...nel.org>, Suren Baghdasaryan <surenb@...gle.com>,
 Michal Hocko <mhocko@...e.com>, Jason Gunthorpe <jgg@...pe.ca>,
 Peter Xu <peterx@...hat.com>
Subject: Re: [PATCH v1] mm/gup: remove (VM_)BUG_ONs

On 6/5/25 03:07, John Hubbard wrote:
> On 6/4/25 7:05 AM, David Hildenbrand wrote:
>> Especially once we hit one of the assertions in
>> sanity_check_pinned_pages(), observing follow-up assertions failing
>> in other code can give good clues about what went wrong, so use
>> VM_WARN_ON_ONCE instead.
>> 
>> While at it, let's just convert all VM_BUG_ON to VM_WARN_ON_ONCE as
>> well. Add one comment for the pfn_valid() check.
> 
> It would be a nice touch to add Linus' notes here, with the BUG() history
> and all. It answers a FAQ about BUG vs. WARN* that is really nice
> to have in the commit log.

Perhaps then rather put it somewhere appropriate in Documentation/process/
than a random commit log?

> This looks great.
> 
> Looking ahead, should we also *delete* VM_BUG_ON*() items? (Not as part 
> of this patch, of course.)
> 
> In any case, 
> 
> Reviewed-by: John Hubbard <jhubbard@...dia.com>
> 
> thanks,