virtio_blk: freeze the virtqueue layout at probe time

init_vq() reads the writable num_request_queues and poll_queues module
parameters both at probe and when recreating virtqueues after suspend
or reset. However, virtio-blk does not update the blk-mq hardware queue
count or queue maps on restore.

Increasing poll_queues can therefore remove the completion callback
from a virtqueue still used for interrupt-driven I/O, leaving requests
uncompleted. Reducing the effective request queue count through
num_request_queues can instead leave existing hardware contexts
indexing beyond the reallocated vblk->vqs array.

Determine the virtqueue count and the split between interrupt-driven
and polling queues once at probe, and reuse this layout when
recreating the virtqueues. Changes to these module parameters then
affect only subsequently probed devices.

Fixes: 0989c41bed96 ("virtio-blk: add num_request_queues module parameter")
Signed-off-by: Yunye Zhao <yunye.zhao@linux.alibaba.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://patch.msgid.link/20261102133740.88919-1-yunye.zhao@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

0 files changed, 0 insertions, 0 deletions