RE: [PATCH] spi: fsl-dspi: fix NULL pointer dereference

[Qiang Zhao]

On Thu, Oct 30, 2020 at 21:02PM, Mark Brown <broonie@xxxxxxxxxx> wrote:

> -----Original Message-----
> From: Mark Brown <broonie@xxxxxxxxxx>
> Sent: 2020年10月30日 21:02
> To: Qiang Zhao <qiang.zhao@xxxxxxx>
> Cc: olteanv@xxxxxxxxx; linux-spi@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] spi: fsl-dspi: fix NULL pointer dereference
> 
> On Thu, Oct 29, 2020 at 04:40:35PM +0800, Qiang Zhao wrote:
> 
> > [   64.587431] Unable to handle kernel NULL pointer dereference at
> > virtual address 0000000000000020
> > [..]
> > [   64.756080] Call trace:
> > [   64.758526]  dspi_suspend+0x30/0x78
> > [   64.762012]  platform_pm_suspend+0x28/0x70
> > [   64.766107]  dpm_run_callback.isra.19+0x24/0x70
> > [   64.770635]  __device_suspend+0xf4/0x2f0
> > [   64.774553]  dpm_suspend+0xec/0x1e0
> > [   64.778036]  dpm_suspend_start+0x80/0xa0
> > [   64.781957]  suspend_devices_and_enter+0x118/0x4f0
> > [   64.786743]  pm_suspend+0x1e0/0x260
> > [   64.790227]  state_store+0x8c/0x118
> > [   64.793712]  kobj_attr_store+0x18/0x30
> > [   64.797459]  sysfs_kf_write+0x40/0x58
> > [   64.801118]  kernfs_fop_write+0x148/0x240
> > [   64.805126]  vfs_write+0xc0/0x230
> > [   64.808436]  ksys_write+0x6c/0x100
> > [   64.811833]  __arm64_sys_write+0x1c/0x28
> > [   64.815753]  el0_svc_common.constprop.3+0x68/0x170
> > [   64.820541]  do_el0_svc+0x24/0x90
> > [   64.823853]  el0_sync_handler+0x118/0x168
> > [   64.827858]  el0_sync+0x158/0x180
> 
> Please think hard before including complete backtraces in upstream reports,
> they are very large and contain almost no useful information relative to their
> size so often obscure the relevant content in your message. If part of the
> backtrace is usefully illustrative (it often is for search engines if nothing else)
> then it's usually better to pull out the relevant sections.

Ok, will modified in next version.

Best Regards,
Qiang Zhao