linux-kernel - Re: [PATCH] mm/memory_hotplug: return zero from do_migrate

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: <388b9a93-423f-33f8-0495-2a4a290fd1aa@redhat.com>
Date:   Wed, 15 Feb 2023 14:16:05 +0100
From:   David Hildenbrand <david@...hat.com>
To:     SeongJae Park <sj@...nel.org>, akpm@...ux-foundation.org
Cc:     osalvador@...e.de, linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mm/memory_hotplug: return zero from do_migrate_range()
 for only success

On 14.02.23 23:32, SeongJae Park wrote:
> do_migrate_range() returns migrate_pages() return value, which zero
> means perfect success, in usual cases.  If all pages are failed to be
> isolated, however, it returns isolate_{lru,movalbe}_page() return
> values, or zero if all pfn were invalid, were hugetlb or hwpoisoned.  So
> do_migrate_range() returning zero means either perfect success, or
> special cases of isolation total failure.
> 
> Actually, the return value is not checked by any caller, so it might be
> better to simply make it a void function.  However, there is a TODO for
> checking the return value.

I'd prefer to not add more dead code ;) Let's not return an error instead.

It's still unclear which kind of fatal migration issues we actually care 
about and how to really detect them.

-- 
Thanks,

David / dhildenb