On Sat, Mar 20, 2021 at 03:19:23PM +0800, Zhiqiang Liu wrote:
> From: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx>
>
> When we make IO stress test on multipath device, there will
> be a metadata err because of wrong path. In the test, we
> concurrent execute 'iscsi device login|logout' and
> 'multipath -r' command with IO stress on multipath device.
> In some case, systemd-udevd may have not time to process
> uevents of iscsi device logout|login, and then 'multipath -r'
> command triggers multipathd daemon calls ioctl to load table
> with incorrect old device info from systemd-udevd.
> Then, one iscsi path may be incorrectly attached to another
> multipath which has different uuid. Finally, the metadata err
> occurs when umounting filesystem to down write metadata on
> the iscsi device which is actually not owned by the multipath
> device.
>
> So we need to check whether all pgpaths of one multipath have
> the same uuid, if not, we should throw a error.
>
> Signed-off-by: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx>
> Signed-off-by: lixiaokeng <lixiaokeng@xxxxxxxxxx>
> Signed-off-by: linfeilong <linfeilong@xxxxxxxxxx>
> Signed-off-by: Wubo <wubo40@xxxxxxxxxx>
> ---
> drivers/md/dm-mpath.c | 52 +++++++++++++++++++++++++++++++++++++++++
> drivers/scsi/scsi_lib.c | 1 +
> 2 files changed, 53 insertions(+)
>
> diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
> index bced42f082b0..f0b995784b53 100644
> --- a/drivers/md/dm-mpath.c
> +++ b/drivers/md/dm-mpath.c
> @@ -24,6 +24,7 @@
> #include <linux/workqueue.h>
> #include <linux/delay.h>
> #include <scsi/scsi_dh.h>
> +#include <linux/dm-ioctl.h>
> #include <linux/atomic.h>
> #include <linux/blk-mq.h>
>
> @@ -1169,6 +1170,45 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
> return r;
> }
>
> +#define SCSI_VPD_LUN_ID_PREFIX_LEN 4
> +#define MPATH_UUID_PREFIX_LEN 7
> +static int check_pg_uuid(struct priority_group *pg, char *md_uuid)
> +{
> + char pgpath_uuid[DM_UUID_LEN] = {0};
> + struct request_queue *q;
> + struct pgpath *pgpath;
> + struct scsi_device *sdev;
> + ssize_t count;
> + int r = 0;
> +
> + list_for_each_entry(pgpath, &pg->pgpaths, list) {
> + q = bdev_get_queue(pgpath->path.dev->bdev);
> + sdev = scsi_device_from_queue(q);
Common dm-multipath code should never poke into scsi internals. This
is something for the device handler to check. It probably also won't
work for all older devices.
