Re: [PATCH 0/6] scsi: make SG_IO user copyback failure-safe

[Bart Van Assche]

On 10/18/26 8:41 AM, Wang Yingjie wrote:
> Several SCSI passthrough completion paths touch userspace while their
> completed request still owns a queue tag.  Sense or READ-bounce copyback
> can fault on a mapping backed by the same one-tag device, leaving the
> nested I/O unable to obtain the retained tag.  The synchronous and
> io_uring BSG paths additionally discard data-copyback failures.
How common are one-tag devices? Has it been considered to disable SG_IO
for one-tag devices instead of complicating the SG_IO implementation?

Thanks,

Bart.