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| author | Bart Van Assche <bvanassche@acm.org> | 2025-10-07 14:48:00 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-07 06:09:31 +0900 |
| commit | 804b5b8e3545445450387ae6891262c421c49304 (patch) | |
| tree | 5b6b81a4fb69136a9dc2567d955ea7fa2f698ff7 /drivers | |
| parent | 67432915145848658149683101104e32f9fd6559 (diff) | |
| download | linux-804b5b8e3545445450387ae6891262c421c49304.tar.gz linux-804b5b8e3545445450387ae6891262c421c49304.tar.bz2 linux-804b5b8e3545445450387ae6891262c421c49304.zip | |
scsi: core: Fix a regression triggered by scsi_host_busy()
[ Upstream commit a0b7780602b1b196f47e527fec82166a7e67c4d0 ]
Commit 995412e23bb2 ("blk-mq: Replace tags->lock with SRCU for tag
iterators") introduced the following regression:
Call trace:
__srcu_read_lock+0x30/0x80 (P)
blk_mq_tagset_busy_iter+0x44/0x300
scsi_host_busy+0x38/0x70
ufshcd_print_host_state+0x34/0x1bc
ufshcd_link_startup.constprop.0+0xe4/0x2e0
ufshcd_init+0x944/0xf80
ufshcd_pltfrm_init+0x504/0x820
ufs_rockchip_probe+0x2c/0x88
platform_probe+0x5c/0xa4
really_probe+0xc0/0x38c
__driver_probe_device+0x7c/0x150
driver_probe_device+0x40/0x120
__driver_attach+0xc8/0x1e0
bus_for_each_dev+0x7c/0xdc
driver_attach+0x24/0x30
bus_add_driver+0x110/0x230
driver_register+0x68/0x130
__platform_driver_register+0x20/0x2c
ufs_rockchip_pltform_init+0x1c/0x28
do_one_initcall+0x60/0x1e0
kernel_init_freeable+0x248/0x2c4
kernel_init+0x20/0x140
ret_from_fork+0x10/0x20
Fix this regression by making scsi_host_busy() check whether the SCSI
host tag set has already been initialized. tag_set->ops is set by
scsi_mq_setup_tags() just before blk_mq_alloc_tag_set() is called. This
fix is based on the assumption that scsi_host_busy() and
scsi_mq_setup_tags() calls are serialized. This is the case in the UFS
driver.
Reported-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Closes: https://lore.kernel.org/linux-block/pnezafputodmqlpumwfbn644ohjybouveehcjhz2hmhtcf2rka@sdhoiivync4y/
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://patch.msgid.link/20251007214800.1678255-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/scsi/hosts.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index eb3e8b41adb1..cf842c97639a 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -594,8 +594,9 @@ int scsi_host_busy(struct Scsi_Host *shost) { int cnt = 0; - blk_mq_tagset_busy_iter(&shost->tag_set, - scsi_host_check_in_flight, &cnt); + if (shost->tag_set.ops) + blk_mq_tagset_busy_iter(&shost->tag_set, + scsi_host_check_in_flight, &cnt); return cnt; } EXPORT_SYMBOL(scsi_host_busy); |