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  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]
Date:   Mon, 15 Apr 2019 13:48:17 -0700
From:   Eric Anholt <eric@...olt.net>
To:     Paul Kocialkowski <paul.kocialkowski@...tlin.com>,
        dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Cc:     David Airlie <airlied@...ux.ie>, Daniel Vetter <daniel@...ll.ch>,
        Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
        Maxime Ripard <maxime.ripard@...tlin.com>,
        Eben Upton <eben@...pberrypi.org>,
        Paul Kocialkowski <paul.kocialkowski@...tlin.com>
Subject: Re: [PATCH v5 3/4] drm/vc4: Check for the binner bo before handling OOM interrupt

Paul Kocialkowski <paul.kocialkowski@...tlin.com> writes:

> Since the OOM interrupt directly deals with the binner bo, it doesn't
> make sense to try and handle it without a binner buffer registered.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
> ---
>  drivers/gpu/drm/vc4/vc4_irq.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_irq.c b/drivers/gpu/drm/vc4/vc4_irq.c
> index ffd0a4388752..723dc86b4511 100644
> --- a/drivers/gpu/drm/vc4/vc4_irq.c
> +++ b/drivers/gpu/drm/vc4/vc4_irq.c
> @@ -64,6 +64,9 @@ vc4_overflow_mem_work(struct work_struct *work)
>  	struct vc4_exec_info *exec;
>  	unsigned long irqflags;
>  
> +	if (!bo)
> +		return;
> +
>  	bin_bo_slot = vc4_v3d_get_bin_slot(vc4);
>  	if (bin_bo_slot < 0) {
>  		DRM_ERROR("Couldn't allocate binner overflow mem\n");
> -- 
> 2.21.0

I don't think this is going to be race-free.  You're checking outside of
a lock, then proceeding to use it even if (in patch 4) the bin BO was in
the process of being freed during the file close path.  Can we put all
of the overflow process here under the same lock as freeing?

Download attachment "signature.asc" of type "application/pgp-signature" (833 bytes)

Powered by blists - more mailing lists