Commit 5e081591 "block: warn if tag is greater than real_max_depth" cleaned up blk_queue_end_tag() to warn when the tag is truly invalid (greater than real_max_depth). However, it changed behavior in the tag < max_depth case to not end the request. Leading to triggering of BUG_ON(blk_queued_rq(rq)) in the request completion path: http://marc.info/?l=linux-kernel&m=132204370518629&w=2 In order to allow blk_queue_resize_tags() to shrink the tag space blk_queue_end_tag() must always complete tags with a value less than real_max_depth regardless of the current max_depth. Cc: Tao Ma <boyu.mt@xxxxxxxxxx> Reported-by: Meelis Roos <mroos@xxxxx> Reported-by: Ed Nadolski <edmund.nadolski@xxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- Functionally the same as Tao Ma's fix [1], but just moves the warn into the if() directly. [1]: http://marc.info/?l=linux-scsi&m=132439698602441&w=2 -- Dan block/blk-tag.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-tag.c b/block/blk-tag.c index e74d6d1..6e61262 100644 --- a/block/blk-tag.c +++ b/block/blk-tag.c @@ -286,12 +286,13 @@ void blk_queue_end_tag(struct request_queue *q, struct request *rq) BUG_ON(tag == -1); - if (unlikely(tag >= bqt->max_depth)) { + if (WARN_ONCE(tag >= bqt->real_max_depth, + "%s: tag %d greater than tag map size: %d\n", + __func__, tag, bqt->real_max_depth)) { /* * This can happen after tag depth has been reduced. * But tag shouldn't be larger than real_max_depth. */ - WARN_ON(tag >= bqt->real_max_depth); return; } -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
