From 9206053d7efb79adb564ccf7055342318b22475c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 26 May 2011 21:06:50 +0200 Subject: [PATCH] block: always allocate genhd->ev if check_events is implemented commit 75e3f3ee3c64968d42f4843ec49e579f84b5aa0c upstream. 9fd097b149 (block: unexport DISK_EVENT_MEDIA_CHANGE for legacy/fringe drivers) removed DISK_EVENT_MEDIA_CHANGE from legacy/fringe block drivers which have inadequate ->check_events(). Combined with earlier change 7c88a168da (block: don't propagate unlisted DISK_EVENTs to userland), this enables using ->check_events() for internal processing while avoiding enabling in-kernel block event polling which can lead to infinite event loop. Unfortunately, this made many drivers including floppy without any bit set in disk->events and ->async_events in which case disk_add_events() simply skipped allocation of disk->ev, which disables whole event handling. As ->check_events() is still used during open processing for revalidation, this can lead to open failure. This patch always allocates disk->ev if ->check_events is implemented. In the long term, it would make sense to simply include the event structure inline into genhd as it's now used by virtually all block devices. Signed-off-by: Tejun Heo Reported-by: Ondrej Zary Reported-by: Alex Villacis Lasso Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- block/genhd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/genhd.c b/block/genhd.c index 2dd988723d73..95822ae25cfe 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1728,7 +1728,7 @@ static void disk_add_events(struct gendisk *disk) { struct disk_events *ev; - if (!disk->fops->check_events || !(disk->events | disk->async_events)) + if (!disk->fops->check_events) return; ev = kzalloc(sizeof(*ev), GFP_KERNEL); -- 2.39.5