Re: [PATCH] scsi: scsi_error: the Error Handler base on SCSI Device

[Bart Van Assche]

On 11/25/25 5:48 AM, JiangJianJun wrote:
> When a SCSI device fails, SCSI locks the host and enters an error handler,
> which causes all I/O operations on the host to be locked. This performance
> impact is even more pronounced when a large number of devices are connected
> to the same host. So I believe it's necessary to downgrade the large lock.
>
> This commit binds an Error Handler to the device, so that when a device
> failure occurs, only the current device is locked. If the device fails to
> recover, the default Error Handler will still be activated.

The current behavior should be retained as the default and the new
behavior should only be enabled if a SCSI LLD requests the new behavior
because many SCSI LLD .eh_host_reset_handler implementations are based
on the assumption that no I/O is in progress if they are called.

Bart.