On 2019-12-15 02:32, Bart Van Assche wrote:
On 12/14/19 8:03 AM, Can Guo wrote:
In ufshcd_remove(), after SCSI host is removed, put it once so that
its
resources can be released.
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b5966fa..a86b0fd 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8251,6 +8251,7 @@ void ufshcd_remove(struct ufs_hba *hba)
ufs_bsg_remove(hba);
ufs_sysfs_remove_nodes(hba->dev);
scsi_remove_host(hba->host);
+ scsi_host_put(hba->host);
/* disable interrupts */
ufshcd_disable_intr(hba, hba->intr_mask);
ufshcd_hba_stop(hba, true);
Hi Can,
The UFS driver may queue work asynchronously and that asynchronous
work may refer to the SCSI host, e.g. ufshcd_err_handler(). Is it
guaranteed that all that asynchronous work has finished before
scsi_host_put() is called?
Thanks,
Bart.
Hi Bart,
Thanks for pointing it out. I noticed that you are changing this
path too in below 2 changes.
https://marc.info/?l=linux-scsi&m=157591520015924&w=2
https://marc.info/?l=linux-scsi&m=157591519915923&w=2
Actually the async works you pointed may also affect your change,
because you may tear down the hba->cmd_queue too early, as there can be
devm commands sent by clock gating, eeh_work and eh_work after that
point,
meaning when blk_get_request is called in exec_dev_cmd(), hba->cmd_queue
may have been released already.
@@ -8263,6 +8232,7 @@ void ufshcd_remove(struct ufs_hba *hba)
{
ufs_bsg_remove(hba);
ufs_sysfs_remove_nodes(hba->dev);
+ blk_cleanup_queue(hba->cmd_queue);
scsi_remove_host(hba->host);
/* disable interrupts */
ufshcd_disable_intr(hba, hba->intr_mask);
How do you think if I replace my patch with below one?
In this way, you can also move blk_cleanup_queue() behind
cancel_work_sync(eh_work).
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b5966fa..bd4ae75 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8251,15 +8251,17 @@ void ufshcd_remove(struct ufs_hba *hba)
ufs_bsg_remove(hba);
ufs_sysfs_remove_nodes(hba->dev);
scsi_remove_host(hba->host);
- /* disable interrupts */
- ufshcd_disable_intr(hba, hba->intr_mask);
- ufshcd_hba_stop(hba, true);
-
ufshcd_exit_clk_scaling(hba);
ufshcd_exit_clk_gating(hba);
if (ufshcd_is_clkscaling_supported(hba))
device_remove_file(hba->dev,
&hba->clk_scaling.enable_attr);
+ cancel_work_sync(&hba->eeh_work);
+ cancel_work_sync(&hba->eh_work);
+ /* disable interrupts */
+ ufshcd_disable_intr(hba, hba->intr_mask);
+ ufshcd_hba_stop(hba, true);
ufshcd_hba_exit(hba);
+ ufshcd_dealloc_host(hba);
}
EXPORT_SYMBOL_GPL(ufshcd_remove);
--
Thanks,
Can Guo.
