This patch fixes the following kernel crash:
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 1 PID: 155 Comm: kworker/1:1H Not tainted 4.16.0-rc5-dbg+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Workqueue: kblockd blk_mq_run_work_fn
Call Trace:
dump_stack+0x85/0xc7
register_lock_class+0x82a/0x830
__lock_acquire+0x141/0x1b10
lock_acquire+0xc9/0x260
_raw_spin_lock_irqsave+0x41/0x50
__wake_up_common_lock+0x9e/0x100
pg_init_done+0x100/0x240 [dm_multipath]
multipath_clone_and_map+0x32c/0x340 [dm_multipath]
map_request+0xc1/0x550 [dm_mod]
dm_mq_queue_rq+0xf9/0x1a0 [dm_mod]
blk_mq_dispatch_rq_list+0x143/0xac0
blk_mq_sched_dispatch_requests+0x23d/0x2f0
__blk_mq_run_hw_queue+0xdb/0x160
process_one_work+0x441/0xa50
worker_thread+0x76/0x6c0
kthread+0x1b2/0x1d0
ret_from_fork+0x24/0x30
==================================================================
BUG: KASAN: null-ptr-deref in __wake_up_common+0x60/0x230
Read of size 8 at addr 0000000000000000 by task kworker/1:1H/155
CPU: 1 PID: 155 Comm: kworker/1:1H Not tainted 4.16.0-rc5-dbg+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Workqueue: kblockd blk_mq_run_work_fn
Call Trace:
dump_stack+0x85/0xc7
kasan_report+0x139/0x350
__wake_up_common+0x60/0x230
__wake_up_common_lock+0xb9/0x100
pg_init_done+0x100/0x240 [dm_multipath]
multipath_clone_and_map+0x32c/0x340 [dm_multipath]
map_request+0xc1/0x550 [dm_mod]
dm_mq_queue_rq+0xf9/0x1a0 [dm_mod]
blk_mq_dispatch_rq_list+0x143/0xac0
blk_mq_sched_dispatch_requests+0x23d/0x2f0
__blk_mq_run_hw_queue+0xdb/0x160
process_one_work+0x441/0xa50
worker_thread+0x76/0x6c0
kthread+0x1b2/0x1d0
ret_from_fork+0x24/0x30
==================================================================
Fixes: 8d47e65948dd ("dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks")
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
---
drivers/md/dm-mpath.c | 66 +++++++++++++++++++++++++++++----------------------
1 file changed, 37 insertions(+), 29 deletions(-)
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 3fde9e9faddd..7d3e572072f5 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -22,7 +22,6 @@
#include <linux/time.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
-#include <scsi/scsi_device.h>
#include <scsi/scsi_dh.h>
#include <linux/atomic.h>
#include <linux/blk-mq.h>
@@ -212,13 +211,25 @@ static int alloc_multipath_stage2(struct dm_target *ti, struct multipath *m)
else
m->queue_mode = DM_TYPE_REQUEST_BASED;
- } else if (m->queue_mode == DM_TYPE_BIO_BASED) {
+ } else if (m->queue_mode == DM_TYPE_BIO_BASED ||
+ m->queue_mode == DM_TYPE_NVME_BIO_BASED) {
INIT_WORK(&m->process_queued_bios, process_queued_bios);
- /*
- * bio-based doesn't support any direct scsi_dh management;
- * it just discovers if a scsi_dh is attached.
- */
- set_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags);
+
+ if (m->queue_mode == DM_TYPE_BIO_BASED) {
+ /*
+ * bio-based doesn't support any direct scsi_dh management;
+ * it just discovers if a scsi_dh is attached.
+ */
+ set_bit(MPATHF_RETAIN_ATTACHED_HW_HANDLER, &m->flags);
+ }
+ }
+
+ if (m->queue_mode != DM_TYPE_NVME_BIO_BASED) {
+ set_bit(MPATHF_QUEUE_IO, &m->flags);
+ atomic_set(&m->pg_init_in_progress, 0);
+ atomic_set(&m->pg_init_count, 0);
+ m->pg_init_delay_msecs = DM_PG_INIT_DELAY_DEFAULT;
+ init_waitqueue_head(&m->pg_init_wait);
}
dm_table_set_type(ti->table, m->queue_mode);
@@ -326,12 +337,14 @@ static void __switch_pg(struct multipath *m, struct priority_group *pg)
{
m->current_pg = pg;
+ if (m->queue_mode == DM_TYPE_NVME_BIO_BASED)
+ return;
+
/* Must we initialise the PG first, and queue I/O till it's ready? */
if (m->hw_handler_name) {
set_bit(MPATHF_PG_INIT_REQUIRED, &m->flags);
set_bit(MPATHF_QUEUE_IO, &m->flags);
} else {
- /* FIXME: not needed if no scsi_dh is attached */
clear_bit(MPATHF_PG_INIT_REQUIRED, &m->flags);
clear_bit(MPATHF_QUEUE_IO, &m->flags);
}
@@ -372,7 +385,8 @@ static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes)
unsigned bypassed = 1;
if (!atomic_read(&m->nr_valid_paths)) {
- clear_bit(MPATHF_QUEUE_IO, &m->flags);
+ if (m->queue_mode != DM_TYPE_NVME_BIO_BASED)
+ clear_bit(MPATHF_QUEUE_IO, &m->flags);
goto failed;
}
@@ -585,7 +599,7 @@ static struct pgpath *__map_bio(struct multipath *m, struct bio *bio)
return pgpath;
}
-static struct pgpath *__map_bio_fast(struct multipath *m, struct bio *bio)
+static struct pgpath *__map_bio_nvme(struct multipath *m, struct bio *bio)
{
struct pgpath *pgpath;
unsigned long flags;
@@ -620,8 +634,8 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio,
{
struct pgpath *pgpath;
- if (!m->hw_handler_name)
- pgpath = __map_bio_fast(m, bio);
+ if (m->queue_mode == DM_TYPE_NVME_BIO_BASED)
+ pgpath = __map_bio_nvme(m, bio);
else
pgpath = __map_bio(m, bio);
@@ -661,7 +675,8 @@ static void process_queued_io_list(struct multipath *m)
{
if (m->queue_mode == DM_TYPE_MQ_REQUEST_BASED)
dm_mq_kick_requeue_list(dm_table_get_md(m->ti->table));
- else if (m->queue_mode == DM_TYPE_BIO_BASED)
+ else if (m->queue_mode == DM_TYPE_BIO_BASED ||
+ m->queue_mode == DM_TYPE_NVME_BIO_BASED)
queue_work(kmultipathd, &m->process_queued_bios);
}
@@ -823,16 +838,6 @@ static int setup_scsi_dh(struct block_device *bdev, struct multipath *m, char **
*/
kfree(m->hw_handler_name);
m->hw_handler_name = attached_handler_name;
-
- /*
- * Init fields that are only used when a scsi_dh is attached
- */
- if (!test_and_set_bit(MPATHF_QUEUE_IO, &m->flags)) {
- atomic_set(&m->pg_init_in_progress, 0);
- atomic_set(&m->pg_init_count, 0);
- m->pg_init_delay_msecs = DM_PG_INIT_DELAY_DEFAULT;
- init_waitqueue_head(&m->pg_init_wait);
- }
}
}
@@ -868,7 +873,6 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
int r;
struct pgpath *p;
struct multipath *m = ti->private;
- struct scsi_device *sdev;
/* we need at least a path arg */
if (as->argc < 1) {
@@ -887,9 +891,7 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
goto bad;
}
- sdev = scsi_device_from_queue(bdev_get_queue(p->path.dev->bdev));
- if (sdev) {
- put_device(&sdev->sdev_gendev);
+ if (m->queue_mode != DM_TYPE_NVME_BIO_BASED) {
INIT_DELAYED_WORK(&p->activate_path, activate_path_work);
r = setup_scsi_dh(p->path.dev->bdev, m, &ti->error);
if (r) {
@@ -999,7 +1001,8 @@ static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
if (!hw_argc)
return 0;
- if (m->queue_mode == DM_TYPE_BIO_BASED) {
+ if (m->queue_mode == DM_TYPE_BIO_BASED ||
+ m->queue_mode == DM_TYPE_NVME_BIO_BASED) {
dm_consume_args(as, hw_argc);
DMERR("bio-based multipath doesn't allow hardware handler args");
return 0;
@@ -1088,6 +1091,8 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
if (!strcasecmp(queue_mode_name, "bio"))
m->queue_mode = DM_TYPE_BIO_BASED;
+ else if (!strcasecmp(queue_mode_name, "nvme"))
+ m->queue_mode = DM_TYPE_NVME_BIO_BASED;
else if (!strcasecmp(queue_mode_name, "rq"))
m->queue_mode = DM_TYPE_REQUEST_BASED;
else if (!strcasecmp(queue_mode_name, "mq"))
@@ -1188,7 +1193,7 @@ static int multipath_ctr(struct dm_target *ti, unsigned argc, char **argv)
ti->num_discard_bios = 1;
ti->num_write_same_bios = 1;
ti->num_write_zeroes_bios = 1;
- if (m->queue_mode == DM_TYPE_BIO_BASED)
+ if (m->queue_mode == DM_TYPE_BIO_BASED || m->queue_mode == DM_TYPE_NVME_BIO_BASED)
ti->per_io_data_size = multipath_per_bio_data_size();
else
ti->per_io_data_size = sizeof(struct dm_mpath_io);
@@ -1725,6 +1730,9 @@ static void multipath_status(struct dm_target *ti, status_type_t type,
case DM_TYPE_BIO_BASED:
DMEMIT("queue_mode bio ");
break;
+ case DM_TYPE_NVME_BIO_BASED:
+ DMEMIT("queue_mode nvme ");
+ break;
case DM_TYPE_MQ_REQUEST_BASED:
DMEMIT("queue_mode mq ");
break;
--
2.16.2
--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel
