linux_dsm_epyc7002/drivers/block
Mauricio Faria de Oliveira fd6625a1ec loop: fix I/O error on fsync() in detached loop devices
commit 4ceddce55eb35d15b0f87f5dcf6f0058fd15d3a4 upstream.

There's an I/O error on fsync() in a detached loop device
if it has been previously attached.

The issue is write cache is enabled in the attach path in
loop_configure() but it isn't disabled in the detach path;
thus it remains enabled in the block device regardless of
whether it is attached or not.

Now fsync() can get an I/O request that will just be failed
later in loop_queue_rq() as device's state is not 'Lo_bound'.

So, disable write cache in the detach path.

Do so based on the queue flag, not the loop device flag for
read-only (used to enable) as the queue flag can be changed
via sysfs even on read-only loop devices (e.g., losetup -r.)

Test-case:

    # DEV=/dev/loop7

    # IMG=/tmp/image
    # truncate --size 1M $IMG

    # losetup $DEV $IMG
    # losetup -d $DEV

Before:

    # strace -e fsync parted -s $DEV print 2>&1 | grep fsync
    fsync(3)                                = -1 EIO (Input/output error)
    Warning: Error fsyncing/closing /dev/loop7: Input/output error
    [  982.529929] blk_update_request: I/O error, dev loop7, sector 0 op 0x1:(WRITE) flags 0x800 phys_seg 0 prio class 0

After:

    # strace -e fsync parted -s $DEV print 2>&1 | grep fsync
    fsync(3)                                = 0

Co-developed-by: Eric Desrochers <eric.desrochers@canonical.com>
Signed-off-by: Eric Desrochers <eric.desrochers@canonical.com>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Tested-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-19 09:44:55 +02:00
..
aoe
drbd
mtip32xx
paride
rnbd block/rnbd-clt: Check the return value of the function rtrs_clt_query 2021-05-19 10:13:06 +02:00
rsxx block: rsxx: fix error return code of rsxx_pci_probe() 2021-03-17 17:06:33 +01:00
xen-blkback xen-blkback: fix compatibility bug with single page rings 2021-05-14 09:50:21 +02:00
zram zram: fix return value on writeback_store 2021-03-17 17:06:34 +01:00
amiflop.c
ataflop.c
brd.c
cryptoloop.c
floppy.c
Kconfig
loop.c loop: fix I/O error on fsync() in detached loop devices 2021-07-19 09:44:55 +02:00
loop.h
Makefile
nbd.c nbd: Fix NULL pointer in flush_workqueue 2021-05-19 10:13:14 +02:00
null_blk_main.c null_blk: fix command timeout completion handling 2021-04-16 11:43:21 +02:00
null_blk_trace.c
null_blk_trace.h
null_blk_zoned.c drivers/block/null_blk/main: Fix a double free in null_init. 2021-05-14 09:50:28 +02:00
null_blk.h null_blk: fix command timeout completion handling 2021-04-16 11:43:21 +02:00
pktcdvd.c
ps3disk.c
ps3vram.c
rbd_types.h
rbd.c
skd_main.c
skd_s1120.h
sunvdc.c
swim3.c
swim_asm.S
swim.c
sx8.c
umem.c umem: fix error return code in mm_pci_probe() 2021-03-30 14:31:50 +02:00
umem.h
virtio_blk.c
xen-blkfront.c
xsysace.c
z2ram.c