diff options
| author | Stanley Chu <stanley.chu@mediatek.com> | 2020-08-09 13:07:34 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-03 11:22:30 +0200 |
| commit | 7a44fce0d135fcb6ce362bf6c5773766dc09e6de (patch) | |
| tree | b8db3a146fbe43b13a035cde184a57b450f0f048 /drivers | |
| parent | cd124e99afd4049c12739d321ddc34a03e04d187 (diff) | |
scsi: ufs: Fix possible infinite loop in ufshcd_hold
[ Upstream commit 93b6c5db06028a3b55122bbb74d0715dd8ca4ae0 ]
In ufshcd_suspend(), after clk-gating is suspended and link is set
as Hibern8 state, ufshcd_hold() is still possibly invoked before
ufshcd_suspend() returns. For example, MediaTek's suspend vops may
issue UIC commands which would call ufshcd_hold() during the command
issuing flow.
Now if UFSHCD_CAP_HIBERN8_WITH_CLK_GATING capability is enabled,
then ufshcd_hold() may enter infinite loops because there is no
clk-ungating work scheduled or pending. In this case, ufshcd_hold()
shall just bypass, and keep the link as Hibern8 state.
Link: https://lore.kernel.org/r/20200809050734.18740-1-stanley.chu@mediatek.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Co-developed-by: Andy Teng <andy.teng@mediatek.com>
Signed-off-by: Andy Teng <andy.teng@mediatek.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 11e917b44a0f..3b4214feae97 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1425,6 +1425,7 @@ unblock_reqs: int ufshcd_hold(struct ufs_hba *hba, bool async) { int rc = 0; + bool flush_result; unsigned long flags; if (!ufshcd_is_clkgating_allowed(hba)) @@ -1456,7 +1457,9 @@ start: break; } spin_unlock_irqrestore(hba->host->host_lock, flags); - flush_work(&hba->clk_gating.ungate_work); + flush_result = flush_work(&hba->clk_gating.ungate_work); + if (hba->clk_gating.is_suspended && !flush_result) + goto out; spin_lock_irqsave(hba->host->host_lock, flags); goto start; } |