From c01a21b77722db0474bbcc4eafc8c4e0d8fed6d8 Mon Sep 17 00:00:00 2001 From: Petr Vorel Date: Thu, 12 Nov 2020 17:50:05 +0100 Subject: [PATCH] loop: Fix occasional uevent drop Commit 716ad0986cbd ("loop: Switch to set_capacity_revalidate_and_notify") causes an occasional drop of loop device uevent, which are no longer triggered in loop_set_size() but in a different part of code. Bug is reproducible with LTP test uevent01 [1]: i=0; while true; do i=$((i+1)); echo "== $i ==" lsmod |grep -q loop && rmmod -f loop ./uevent01 || break done Put back triggering through code called in loop_set_size(). Fix required to add yet another parameter to set_capacity_revalidate_and_notify(). [1] https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/uevents/uevent01.c [hch: rebased on a different change to the prototype of set_capacity_revalidate_and_notify] Cc: stable@vger.kernel.org # v5.9 Fixes: 716ad0986cbd ("loop: Switch to set_capacity_revalidate_and_notify") Reported-by: Signed-off-by: Petr Vorel Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/block/loop.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index cb1191d..a58084c 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -255,7 +255,8 @@ static void loop_set_size(struct loop_device *lo, loff_t size) bd_set_nr_sectors(bdev, size); - set_capacity_revalidate_and_notify(lo->lo_disk, size, false); + if (!set_capacity_revalidate_and_notify(lo->lo_disk, size, false)) + kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE); } static inline int -- 2.7.4