linux-kernel - Re: [PATCH v3 07/11] lib/ref_tracker: remove warnings in case of allocation failure

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: <CANn89i+E3z-iXSJh8316KSycYk2VTS-n0E=tAOj23fuDSi1Zjg@mail.gmail.com>
Date:   Mon, 21 Feb 2022 15:54:12 -0800
From:   Eric Dumazet <edumazet@...gle.com>
To:     Andrzej Hajda <andrzej.hajda@...el.com>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        netdev <netdev@...r.kernel.org>,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Daniel Vetter <daniel@...ll.ch>,
        Lucas De Marchi <lucas.demarchi@...el.com>,
        Chris Wilson <chris.p.wilson@...el.com>,
        Dmitry Vyukov <dvyukov@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>
Subject: Re: [PATCH v3 07/11] lib/ref_tracker: remove warnings in case of
 allocation failure

On Mon, Feb 21, 2022 at 3:26 PM Andrzej Hajda <andrzej.hajda@...el.com> wrote:
>
> Library can handle allocation failures. To avoid allocation warnings
> __GFP_NOWARN has been added everywhere. Moreover GFP_ATOMIC has been
> replaced with GFP_NOWAIT in case of stack allocation on tracker free
> call.
>
> Signed-off-by: Andrzej Hajda <andrzej.hajda@...el.com>
> ---
>  lib/ref_tracker.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c
> index 2ef4596b6b36f..cae4498fcfd70 100644
> --- a/lib/ref_tracker.c
> +++ b/lib/ref_tracker.c
> @@ -189,7 +189,7 @@ int ref_tracker_alloc(struct ref_tracker_dir *dir,
>         unsigned long entries[REF_TRACKER_STACK_ENTRIES];
>         struct ref_tracker *tracker;
>         unsigned int nr_entries;
> -       gfp_t gfp_mask = gfp;
> +       gfp_t gfp_mask = gfp | __GFP_NOWARN;

SGTM

>         unsigned long flags;
>
>         WARN_ON_ONCE(dir->dead);
> @@ -237,7 +237,8 @@ int ref_tracker_free(struct ref_tracker_dir *dir,
>                 return -EEXIST;
>         }
>         nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 1);
> -       stack_handle = stack_depot_save(entries, nr_entries, GFP_ATOMIC);
> +       stack_handle = stack_depot_save(entries, nr_entries,
> +                                       GFP_NOWAIT | __GFP_NOWARN);

Last time I looked at this, __GFP_NOWARN was enforced in __stack_depot_save()

>
>         spin_lock_irqsave(&dir->lock, flags);
>         if (tracker->dead) {
> --
> 2.25.1
>