On Tue, Sep 27, 2022 at 5:09 AM Keith Busch [off-list ref] wrote:

From: Keith Busch <kbusch@kernel.org>

The hctx's work may be racing with the elevator switch that occurs when
reinitializing hardware queues. This happens because the queue is merely
frozen in this context, but that only prevents requests from allocating
and doesn't stop the hctx work from running. When swapping the io
scheduler, this leaves a race condition open where the work may get a
pointer to an elevator that's being torn down. Use the quiesced elevator
switch instead.

Signed-off-by: Keith Busch <kbusch@kernel.org>

This patch should fix one kernel panic when running stress
test(elevator switch vs
nvme pci reset/scan).

Reviewed-by: Ming Lei <redacted>