From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Fri, 25 Mar 2011 08:36:30 +0000
Subject: [PATCH 1/1] ARM: dmabounce: fix dmabounce may cause crash issue
In-Reply-To: <1300965400-28304-1-git-send-email-b29396@freescale.com>
References: <1300965400-28304-1-git-send-email-b29396@freescale.com>
Message-ID: <20110325083630.GA26481@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Thu, Mar 24, 2011 at 07:16:40PM +0800, Aisheng.Dong wrote:
> The map_single does not check if dev is NULL which may cause kernel panic
> like follows:
> Unable to handle kernel NULL pointer dereference at virtual address 000000bc
> pgd = 80004000
> [000000bc] *pgd=00000000
> Internal error: Oops: 5 [#1] PREEMPT
> last sysfs file:
> Modules linked in:
> CPU: 0    Not tainted  (2.6.35.3-00845-g204c152-dirty #112)
> PC is at dma_map_single+0x2c/0x2a0
> LR is at fec_enet_interrupt+0x1d4/0x450
> pc : [<8003cf04>]    lr : [<802936b8>]    psr: 60000193
> sp : 80809ec8  ip : 00000080  fp : 99308040
> r10: 99308040  r9 : 00000002  r8 : 99074f00
> r7 : fa0a5000  r6 : 00000000  r5 : 00000060  r4 : 992e4000
> r3 : 00000002  r2 : 8080cac0  r1 : 99308040  r0 : 00000000
> 
> The patch checks the dev to avoid this issue and align with the
> original dma_map_single to allow dev is NULL.

Is there a reason that the FEC code can't pass the appropriate struct
device?