Re: [PATCH 1/5] scsi: ufs: core: Cancel RTC work during ufshcd_remove()

["Peter Wang (王信友)" <peter.wang@mediatek.com>]

On Mon, 2024-11-11 at 23:18 +0530, Manivannan Sadhasivam via B4 Relay
wrote:
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> 
> From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> 
> Currently, RTC work is only cancelled during __ufshcd_wl_suspend().
> When
> ufshcd is removed in ufshcd_remove(), RTC work is not cancelled. Due
> to
> this, any further trigger of the RTC work after ufshcd_remove() would
> result in a NULL pointer dereference as below:
> 
> Unable to handle kernel NULL pointer dereference at virtual address
> 00000000000002a4
> Workqueue: events ufshcd_rtc_work
> Call trace:
>  _raw_spin_lock_irqsave+0x34/0x8c
>  pm_runtime_get_if_active+0x24/0xb4
>  ufshcd_rtc_work+0x124/0x19c
>  process_scheduled_works+0x18c/0x2d8
>  worker_thread+0x144/0x280
>  kthread+0x11c/0x128
>  ret_from_fork+0x10/0x20
> 
> Since RTC work accesses the ufshcd internal structures, it should be
> cancelled
> when ufshcd is removed. So do that in ufshcd_remove(), as per the
> order in
> ufshcd_init().
> 
> Cc: stable@vger.kernel.org # 6.8
> Fixes: 6bf999e0eb41 ("scsi: ufs: core: Add UFS RTC support")
> Signed-off-by: Manivannan Sadhasivam <
> manivannan.sadhasivam@linaro.org>
> ---
>  drivers/ufs/core/ufshcd.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> 

Reviewed-by: Peter Wang <peter.wang@mediatek.com>