Re: [PATCH] dma: pl330: Fix bug to allocate resources on ARM 64bit SoC

[Chanwoo Choi <cw00.choi@samsung.com>]

Hi Vinod,

On 11/12/2014 08:30 PM, Vinod Koul wrote:
> On Wed, Nov 12, 2014 at 08:02:13PM +0900, Chanwoo Choi wrote:
>> This patch fix following bug to allocate resources on ARM 64bit SoC.
>> The patch[1] adds to check wheter dev is NULL or not.
> 
> Fixed already by below in my tree

Thanks for reply.
Chanwoo Choi

> 
> commit 1d7e691f1b1793f8a9439b2e8eae069e5996a187
> Author: Andrew Jackson <Andrew.Jackson@arm.com>
> Date:   Thu Nov 6 11:39:47 2014 +0000
> 
>     dmaengine: pl330: Correct device assignment.
> 
>     Commit f6f2421c0a1c removed pl330_info structure by embedding it into
>     pl330_dmac structure, but did not ensure that the dmac->ddma.dev
>     pointer gets initialised before use. When dma_alloc_coherent() gets
>     called on arm64 a WARN() gets triggered due to dev being NULL.
> 
>     ------------[ cut here ]------------
>     WARNING: CPU: 1 PID: 1 at arch/arm64/mm/dma-mapping.c:49
> __dma_alloc_coherent+0xd0/0xe0()
>     Use an actual device structure for DMA allocation
>     Modules linked in:
>     CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.17.0+ #5
>     Call trace:
>     [<ffffffc000087f24>] dump_backtrace+0x0/0x130
>     [<ffffffc000088064>] show_stack+0x10/0x1c
>     [<ffffffc0004e8af8>] dump_stack+0x74/0xb8
>     [<ffffffc0000aa444>] warn_slowpath_common+0x8c/0xb4
>     [<ffffffc0000aa4b8>] warn_slowpath_fmt+0x4c/0x58
>     [<ffffffc000092580>] __dma_alloc_coherent+0xcc/0xe0
>     [<ffffffc000092734>] __dma_alloc_noncoherent+0x64/0x158
>     [<ffffffc000312cd8>] pl330_probe+0x650/0x8f0
>     [<ffffffc00030e1d4>] amba_probe+0xa0/0xc8
>     [<ffffffc000350240>] really_probe+0xc4/0x22c
>     [<ffffffc0003504b4>] __driver_attach+0xa0/0xa8
>     [<ffffffc00034e5fc>] bus_for_each_dev+0x54/0x98
>     [<ffffffc00034fd8c>] driver_attach+0x1c/0x28
>     [<ffffffc00034fa08>] bus_add_driver+0x14c/0x204
>     [<ffffffc000350b84>] driver_register+0x64/0x130
>     [<ffffffc00030dcf8>] amba_driver_register+0x50/0x5c
>     [<ffffffc0006a60d0>] pl330_driver_init+0x10/0x1c
>     [<ffffffc0000814ac>] do_one_initcall+0x88/0x19c
>     [<ffffffc00068dab8>] kernel_init_freeable+0x140/0x1e0
>     [<ffffffc0004e5e18>] kernel_init+0x10/0xd4
>     ---[ end trace 76f2d47a444e523e ]---
>     (NULL device *): dmac_alloc_resources:1821 Can't allocate memory!
>     (NULL device *): Unable to create channels for DMAC
> 
>     This patch will also ensure that any dev_err messages are printed
>     with the appropriate device name.
> 
>     Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
>     Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
>     Signed-off-by: Vinod Koul <vinod.koul@intel.com>
>