On 25/02/2022 01:56, Jaegeuk Kim wrote:
> The commit b294ff3e3449 ("scsi: ufs: core: Enable power management for wlun")
> moved hba->shutting_down from ufshcd_shutdown to ufshcd_wl_shutdown, which
> introduced regression as belows.
>
> ufshcd_err_handler started; HBA state eh_non_fatal; powered 1; shutting down 1; saved_err = 4; saved_uic_err = 64; force_reset = 0
> ...
> task:init state:D stack: 0 pid: 1 ppid: 0 flags:0x04000008
> Call trace:
> __switch_to+0x25c/0x5e0
> __schedule+0x68c/0xaa8
> schedule+0x12c/0x24c
> schedule_timeout+0x98/0x138
> wait_for_common_io+0x13c/0x30c
> blk_execute_rq+0xb0/0x10c
> __scsi_execute+0x100/0x27c
> ufshcd_set_dev_pwr_mode+0x1c8/0x408
> __ufshcd_wl_suspend+0x564/0x688
> ufshcd_wl_shutdown+0xa8/0xc0
> device_shutdown+0x234/0x578
> kernel_restart+0x4c/0x140
> __arm64_sys_reboot+0x3a0/0x414
> el0_svc_common+0xd0/0x1e4
> el0_svc+0x28/0x88
> el0_sync_handler+0x8c/0xf0
> el0_sync+0x1c0/0x200
>
> The init for reboot was stuck, since ufshcd_err_hanlder was skipped when
> shutting down WLUN. This patch allows to run the error handler and let
> disable it during final ufshcd_shutdown only.
I do not understand why it is stuck? If there was a non-fatal error, the
request should complete anyway, or at least timeout.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: b294ff3e3449 ("scsi: ufs: core: Enable power management for wlun")
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
> drivers/scsi/ufs/ufshcd.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 460d2b440d2e..a37813b474d0 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -9178,10 +9178,6 @@ static void ufshcd_wl_shutdown(struct device *dev)
>
> hba = shost_priv(sdev->host);
>
> - down(&hba->host_sem);
> - hba->shutting_down = true;
> - up(&hba->host_sem);
> -
> /* Turn on everything while shutting down */
> ufshcd_rpm_get_sync(hba);
> scsi_device_quiesce(sdev);
> @@ -9387,6 +9383,10 @@ EXPORT_SYMBOL(ufshcd_runtime_resume);
> */
> int ufshcd_shutdown(struct ufs_hba *hba)
> {
> + down(&hba->host_sem);
> + hba->shutting_down = true;
> + up(&hba->host_sem);
This does not seem right because the device is not accessible after
__ufshcd_wl_suspend(hba, UFS_SHUTDOWN_PM), so shutting_down needs to
be set before.
> +
> if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba))
> goto out;
>
