From 694521cb3fadea6052328f507351a820a2529b8e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Tue, 15 Apr 2025 10:51:47 +0200 Subject: [PATCH] loop: properly send KOBJ_CHANGED uevent for disk device MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit e7bc0010ceb403d025100698586c8e760921d471 upstream. The original commit message and the wording "uncork" in the code comment indicate that it is expected that the suppressed event instances are automatically sent after unsuppressing. This is not the case, instead they are discarded. In effect this means that no "changed" events are emitted on the device itself by default. While each discovered partition does trigger a changed event on the device, devices without partitions don't have any event emitted. This makes udev miss the device creation and prompted workarounds in userspace. See the linked util-linux/losetup bug. Explicitly emit the events and drop the confusingly worded comments. Link: https://github.com/util-linux/util-linux/issues/2434 Fixes: 498ef5c777d9 ("loop: suppress uevents while reconfiguring the device") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20250415-loop-uevent-changed-v2-1-0c4e6a923b2a@linutronix.de Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/block/loop.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 0be518b9ed64..e5ae43278ff4 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -573,8 +573,8 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, error = 0; done: - /* enable and uncork uevent now that we are done */ dev_set_uevent_suppress(disk_to_dev(lo->lo_disk), 0); + kobject_uevent(&disk_to_dev(lo->lo_disk)->kobj, KOBJ_CHANGE); return error; out_err: @@ -1034,8 +1034,8 @@ static int loop_configure(struct loop_device *lo, blk_mode_t mode, if (partscan) clear_bit(GD_SUPPRESS_PART_SCAN, &lo->lo_disk->state); - /* enable and uncork uevent now that we are done */ dev_set_uevent_suppress(disk_to_dev(lo->lo_disk), 0); + kobject_uevent(&disk_to_dev(lo->lo_disk)->kobj, KOBJ_CHANGE); loop_global_unlock(lo, is_loop); if (partscan)