linux-kernel - Re: [PATCH] docs/core-api: memory-allocation: GFP_NOWAIT doesn't need __GFP

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] [day] [month] [year] [list]

Message-ID: <877cd3aopm.fsf@trenco.lwn.net>
Date: Mon, 29 Jul 2024 15:11:01 -0600
From: Jonathan Corbet <corbet@....net>
To: Dave Martin <Dave.Martin@....com>, linux-kernel@...r.kernel.org
Cc: linux-doc@...r.kernel.org, Matthew Wilcox <willy@...radead.org>, Mike
 Rapoport <rppt@...nel.org>
Subject: Re: [PATCH] docs/core-api: memory-allocation: GFP_NOWAIT doesn't
 need __GFP_NOWARN

Dave Martin <Dave.Martin@....com> writes:

> Since v6.8 the definition of GFP_NOWAIT has implied __GFP_NOWARN,
> so it is now redundant to add this flag explicitly.
>
> Update the docs to match, and emphasise the need for a fallback
> when using GFP_NOWAIT.
>
> Fixes: 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT")
> Signed-off-by: Dave Martin <Dave.Martin@....com>
>
> ---
>
> Based on: v6.11-rc1
>
> This change also evaporates the apparent typo of __GFP_NOWARN without
> the underscores in the documentation, but that doesn't really feel like
> it merits a dedicated patch.
>
> Not sure if this really merits a Fixes tag, but the docmuentation
> update might as well be picked into trees that have the corresponding
> code change.
>
> ---
>  Documentation/core-api/memory-allocation.rst | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/core-api/memory-allocation.rst b/Documentation/core-api/memory-allocation.rst
> index 8b84eb4bdae7..0f19dd524323 100644
> --- a/Documentation/core-api/memory-allocation.rst
> +++ b/Documentation/core-api/memory-allocation.rst
> @@ -45,8 +45,9 @@ here we briefly outline their recommended usage:
>    * If the allocation is performed from an atomic context, e.g interrupt
>      handler, use ``GFP_NOWAIT``. This flag prevents direct reclaim and
>      IO or filesystem operations. Consequently, under memory pressure
> -    ``GFP_NOWAIT`` allocation is likely to fail. Allocations which
> -    have a reasonable fallback should be using ``GFP_NOWARN``.
> +    ``GFP_NOWAIT`` allocation is likely to fail. Users of this flag need
> +    to provide a suitable fallback to cope with such failures where
> +    appropriate.
>    * If you think that accessing memory reserves is justified and the kernel

Applied, thanks.

jon