linux-kernel - Re: [RFC][PATCH 1/1] drm/amdkfd: Remove redundant pdd validation

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]

Date:	Thu, 9 Jul 2015 11:47:21 +0300
From:	Oded Gabbay <oded.gabbay@...il.com>
To:	Maninder Singh <maninder1.s@...sung.com>
Cc:	David Airlie <airlied@...ux.ie>,
	Maling list - DRI developers 
	<dri-devel@...ts.freedesktop.org>,
	"Linux-Kernel@...r. Kernel. Org" <linux-kernel@...r.kernel.org>,
	pankaj.m@...sung.com
Subject: Re: [RFC][PATCH 1/1] drm/amdkfd: Remove redundant pdd validation

On Mon, Jun 29, 2015 at 7:33 AM, Maninder Singh <maninder1.s@...sung.com> wrote:
>
> pdd is already dereferenced before this check.
> So it is redundtant to validate pdd here.
>
> Signed-off-by: Maninder Singh <maninder1.s@...sung.com>
> ---
>  drivers/gpu/drm/amd/amdkfd/kfd_process.c |    3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> index 8a1f999..4dbc4e5 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> @@ -431,8 +431,7 @@ void kfd_unbind_process_from_device(struct kfd_dev *dev, unsigned int pasid)
>          * We don't call amd_iommu_unbind_pasid() here
>          * because the IOMMU called us.
>          */
> -       if (pdd)
> -               pdd->bound = false;
> +       pdd->bound = false;
>
>         mutex_unlock(&p->mutex);
>  }
> --
> 1.7.9.5
>
Hi Maninder,

You are correct pdd was already dereferenced so this check is
redundant. However, I think a better patch would be to move the check
to where pdd is first acquired (a few lines above it), because I don't
see there any check.

Could you please do that and resend the patch ? Use latest v4.2-rc1
label from Linus please.

Thansk,

   Oded
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/