* [PATCH V2 1/1] scsi: ufs: Fix a possible NULL pointer issue
@ 2020-12-14 3:41 Can Guo
2020-12-14 14:32 ` Bean Huo
0 siblings, 1 reply; 3+ messages in thread
From: Can Guo @ 2020-12-14 3:41 UTC (permalink / raw)
To: asutoshd, nguyenb, hongwus, rnayak, linux-scsi, kernel-team,
saravanak, salyzyn, cang
Cc: Alim Akhtar, Avri Altman, James E.J. Bottomley,
Martin K. Petersen, Stanley Chu, Bean Huo, Bart Van Assche,
open list
During system resume/suspend, hba could be NULL. In this case, do not touch
eh_sem.
Fixes: 88a92d6ae4fe ("scsi: ufs: Serialize eh_work with system PM events and async scan")
Signed-off-by: Can Guo <cang@codeaurora.org>
---
drivers/scsi/ufs/ufshcd.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c1c401b..ef155a9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8883,8 +8883,11 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
int ret = 0;
ktime_t start = ktime_get();
+ if (!hba)
+ return 0;
+
down(&hba->eh_sem);
- if (!hba || !hba->is_powered)
+ if (!hba->is_powered)
return 0;
if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
@@ -8932,10 +8935,8 @@ int ufshcd_system_resume(struct ufs_hba *hba)
int ret = 0;
ktime_t start = ktime_get();
- if (!hba) {
- up(&hba->eh_sem);
+ if (!hba)
return -EINVAL;
- }
if (!hba->is_powered || pm_runtime_suspended(hba->dev))
/*
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH V2 1/1] scsi: ufs: Fix a possible NULL pointer issue
2020-12-14 3:41 [PATCH V2 1/1] scsi: ufs: Fix a possible NULL pointer issue Can Guo
@ 2020-12-14 14:32 ` Bean Huo
2020-12-18 5:42 ` Can Guo
0 siblings, 1 reply; 3+ messages in thread
From: Bean Huo @ 2020-12-14 14:32 UTC (permalink / raw)
To: Can Guo, asutoshd, nguyenb, hongwus, rnayak, linux-scsi,
kernel-team, saravanak, salyzyn
Cc: Alim Akhtar, Avri Altman, James E.J. Bottomley,
Martin K. Petersen, Stanley Chu, Bean Huo, Bart Van Assche,
open list
On Sun, 2020-12-13 at 19:41 -0800, Can Guo wrote:
> Fixes: 88a92d6ae4fe ("scsi: ufs: Serialize eh_work with system PM
> events and async scan")
>
> Signed-off-by: Can Guo <cang@codeaurora.org>
> ---
> drivers/scsi/ufs/ufshcd.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index c1c401b..ef155a9 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -8883,8 +8883,11 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
> int ret = 0;
> ktime_t start = ktime_get();
>
> + if (!hba)
> + return 0;
> +
> down(&hba->eh_sem);
> - if (!hba || !hba->is_powered)
> + if (!hba->is_powered)
> return 0;
Can,
why not moving down(&hba->eh_sem) after "return 0;"?
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH V2 1/1] scsi: ufs: Fix a possible NULL pointer issue
2020-12-14 14:32 ` Bean Huo
@ 2020-12-18 5:42 ` Can Guo
0 siblings, 0 replies; 3+ messages in thread
From: Can Guo @ 2020-12-18 5:42 UTC (permalink / raw)
To: Bean Huo
Cc: asutoshd, nguyenb, hongwus, rnayak, linux-scsi, kernel-team,
saravanak, salyzyn, Alim Akhtar, Avri Altman,
James E.J. Bottomley, Martin K. Petersen, Stanley Chu, Bean Huo,
Bart Van Assche, open list
On 2020-12-14 22:32, Bean Huo wrote:
> On Sun, 2020-12-13 at 19:41 -0800, Can Guo wrote:
>> Fixes: 88a92d6ae4fe ("scsi: ufs: Serialize eh_work with system PM
>> events and async scan")
>>
>> Signed-off-by: Can Guo <cang@codeaurora.org>
>> ---
>> drivers/scsi/ufs/ufshcd.c | 9 +++++----
>> 1 file changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index c1c401b..ef155a9 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -8883,8 +8883,11 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
>> int ret = 0;
>> ktime_t start = ktime_get();
>>
>> + if (!hba)
>> + return 0;
>> +
>> down(&hba->eh_sem);
>> - if (!hba || !hba->is_powered)
>> + if (!hba->is_powered)
>> return 0;
>
>
> Can,
>
> why not moving down(&hba->eh_sem) after "return 0;"?
In your way, if hba is not powered, ufshcd_system_suspend() returns
0, which is a successful suspend. When ufshcd_system_resume() is called,
if hba is not powered, it goes to out and does up(&hba->eh_sem), which
shall cause unbalance to eh_sem.
Thanks,
Can Guo.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-12-18 5:43 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-12-14 3:41 [PATCH V2 1/1] scsi: ufs: Fix a possible NULL pointer issue Can Guo
2020-12-14 14:32 ` Bean Huo
2020-12-18 5:42 ` Can Guo
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).