On 2023/3/21 22:22, Benjamin Block wrote:
On Tue, Mar 21, 2023 at 04:42:04PM +0800, Ye Bin wrote:
From: Ye Bin <yebin10@xxxxxxxxxx>
When do follow test:
Step1: echo "recovery" > /sys/class/scsi_host/host0/state
Hmm, that make me wonder, what potential use-case this is for? Just
testing?
Thank you for your reply.
Actually, I'm looking for a way to temporarily stop sending IO to the
driver.
Setting the state of the host to recovery can do this, but I changed the
state to
running and found that the process could not be woken up.
I don't know what the purpose of designing this sysfs interface was. But
this
modification can solve the effect I want to achieve.
For SDEVs we explicitly filter what states can be set from user-space.
Only `SDEV_RUNNING` and `SDEV_OFFLINE` can be set in
`store_state_field()`.
There is probably quite a few other bad things you can do with this
interface by using any of the other states used for device destruction
or EH, and then trigger I/O or said destruction/EH otherwise.
Not sure handling this one special case of `SHOST_RECOVERY` is quite
enough.
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index ee28f73af4d4..ae6b1476b869 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -216,6 +216,9 @@ store_shost_state(struct device *dev, struct device_attribute *attr,
if (scsi_host_set_state(shost, state))
return -EINVAL;
+ else
+ wake_up(&shost->host_wait);
+
return count;
}
--
2.31.1
