From 2a07bb64d80152701d507b1498237ed1b8d83866 Mon Sep 17 00:00:00 2001 From: Eric Farman Date: Mon, 12 Aug 2024 14:57:32 +0200 Subject: [PATCH 1/4] s390/dasd: Remove DMA alignment This reverts commit bc792884b76f ("s390/dasd: Establish DMA alignment"). Quoting the original commit: linux-next commit bf8d08532bc1 ("iomap: add support for dma aligned direct-io") changes the alignment requirement to come from the block device rather than the block size, and the default alignment requirement is 512-byte boundaries. Since DASD I/O has page alignments for IDAW/TIDAW requests, let's override this value to restore the expected behavior. I mentioned TIDAW, but that was wrong. TIDAWs have no distinct alignment requirement (per p. 15-70 of POPS SA22-7832-13): Unless otherwise specified, TIDAWs may designate a block of main storage on any boundary and length up to 4K bytes, provided the specified block does not cross a 4 K-byte boundary. IDAWs do, but the original commit neglected that while ECKD DASD are typically formatted in 4096-byte blocks, they don't HAVE to be. Formatting an ECKD volume with smaller blocks is permitted (dasdfmt -b xxx), and the problematic commit enforces alignment properties to such a device that will result in errors, such as: [test@host ~]# lsdasd -l a367 | grep blksz blksz: 512 [test@host ~]# mkfs.xfs -f /dev/disk/by-path/ccw-0.0.a367-part1 meta-data=/dev/dasdc1 isize=512 agcount=4, agsize=230075 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=1 = reflink=1 bigtime=1 inobtcount=1 nrext64=1 data = bsize=4096 blocks=920299, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=1 log =internal log bsize=4096 blocks=16384, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 error reading existing superblock: Invalid argument mkfs.xfs: pwrite failed: Invalid argument libxfs_bwrite: write failed on (unknown) bno 0x70565c/0x100, err=22 mkfs.xfs: Releasing dirty buffer to free list! found dirty buffer (bulk) on free list! mkfs.xfs: pwrite failed: Invalid argument ...snipped... The original commit omitted the FBA discipline for just this reason, but the formatted block size of the other disciplines was overlooked. The solution to all of this is to revert to the original behavior, such that the block size can be respected. There were two commits [1] that moved this code in the interim, so a straight git-revert is not possible, but the change is straightforward. But what of the original problem? That was manifested with a direct-io QEMU guest, where QEMU itself was changed a month or two later with commit 25474d90aa ("block: use the request length for iov alignment") such that the blamed kernel commit is unnecessary. [1] commit 0127a47f58c6 ("dasd: move queue setup to common code") commit fde07a4d74e3 ("dasd: use the atomic queue limits API") Fixes: bc792884b76f ("s390/dasd: Establish DMA alignment") Reviewed-by: Stefan Haberland Signed-off-by: Eric Farman Signed-off-by: Stefan Haberland Link: https://lore.kernel.org/r/20240812125733.126431-2-sth@linux.ibm.com Signed-off-by: Jens Axboe --- drivers/s390/block/dasd_genhd.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c index 1aa426b1dedd..6da47a65af61 100644 --- a/drivers/s390/block/dasd_genhd.c +++ b/drivers/s390/block/dasd_genhd.c @@ -41,7 +41,6 @@ int dasd_gendisk_alloc(struct dasd_block *block) */ .max_segment_size = PAGE_SIZE, .seg_boundary_mask = PAGE_SIZE - 1, - .dma_alignment = PAGE_SIZE - 1, .max_segments = USHRT_MAX, }; struct gendisk *gdp; From 7db4042336580dfd75cb5faa82c12cd51098c90b Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Mon, 12 Aug 2024 14:57:33 +0200 Subject: [PATCH 2/4] s390/dasd: fix error recovery leading to data corruption on ESE devices Extent Space Efficient (ESE) or thin provisioned volumes need to be formatted on demand during usual IO processing. The dasd_ese_needs_format function checks for error codes that signal the non existence of a proper track format. The check for incorrect length is to imprecise since other error cases leading to transport of insufficient data also have this flag set. This might lead to data corruption in certain error cases for example during a storage server warmstart. Fix by removing the check for incorrect length and replacing by explicitly checking for invalid track format in transport mode. Also remove the check for file protected since this is not a valid ESE handling case. Cc: stable@vger.kernel.org # 5.3+ Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes") Reviewed-by: Jan Hoeppner Signed-off-by: Stefan Haberland Link: https://lore.kernel.org/r/20240812125733.126431-3-sth@linux.ibm.com Signed-off-by: Jens Axboe --- drivers/s390/block/dasd.c | 36 ++++++++++++------- drivers/s390/block/dasd_3990_erp.c | 10 ++---- drivers/s390/block/dasd_eckd.c | 57 +++++++++++++----------------- drivers/s390/block/dasd_int.h | 2 +- 4 files changed, 51 insertions(+), 54 deletions(-) diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 0a97cfedd706..42a4a996defb 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -1601,9 +1601,15 @@ static int dasd_ese_needs_format(struct dasd_block *block, struct irb *irb) if (!sense) return 0; - return !!(sense[1] & SNS1_NO_REC_FOUND) || - !!(sense[1] & SNS1_FILE_PROTECTED) || - scsw_cstat(&irb->scsw) == SCHN_STAT_INCORR_LEN; + if (sense[1] & SNS1_NO_REC_FOUND) + return 1; + + if ((sense[1] & SNS1_INV_TRACK_FORMAT) && + scsw_is_tm(&irb->scsw) && + !(sense[2] & SNS2_ENV_DATA_PRESENT)) + return 1; + + return 0; } static int dasd_ese_oos_cond(u8 *sense) @@ -1624,7 +1630,7 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, struct dasd_device *device; unsigned long now; int nrf_suppressed = 0; - int fp_suppressed = 0; + int it_suppressed = 0; struct request *req; u8 *sense = NULL; int expires; @@ -1679,8 +1685,9 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, */ sense = dasd_get_sense(irb); if (sense) { - fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) && - test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags); + it_suppressed = (sense[1] & SNS1_INV_TRACK_FORMAT) && + !(sense[2] & SNS2_ENV_DATA_PRESENT) && + test_bit(DASD_CQR_SUPPRESS_IT, &cqr->flags); nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) && test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags); @@ -1695,7 +1702,7 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, return; } } - if (!(fp_suppressed || nrf_suppressed)) + if (!(it_suppressed || nrf_suppressed)) device->discipline->dump_sense_dbf(device, irb, "int"); if (device->features & DASD_FEATURE_ERPLOG) @@ -2459,14 +2466,17 @@ retry: rc = 0; list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) { /* - * In some cases the 'File Protected' or 'Incorrect Length' - * error might be expected and error recovery would be - * unnecessary in these cases. Check if the according suppress - * bit is set. + * In some cases certain errors might be expected and + * error recovery would be unnecessary in these cases. + * Check if the according suppress bit is set. */ sense = dasd_get_sense(&cqr->irb); - if (sense && sense[1] & SNS1_FILE_PROTECTED && - test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags)) + if (sense && (sense[1] & SNS1_INV_TRACK_FORMAT) && + !(sense[2] & SNS2_ENV_DATA_PRESENT) && + test_bit(DASD_CQR_SUPPRESS_IT, &cqr->flags)) + continue; + if (sense && (sense[1] & SNS1_NO_REC_FOUND) && + test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags)) continue; if (scsw_cstat(&cqr->irb.scsw) == 0x40 && test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags)) diff --git a/drivers/s390/block/dasd_3990_erp.c b/drivers/s390/block/dasd_3990_erp.c index bbbacfc386f2..d0aa267462c5 100644 --- a/drivers/s390/block/dasd_3990_erp.c +++ b/drivers/s390/block/dasd_3990_erp.c @@ -1386,14 +1386,8 @@ dasd_3990_erp_file_prot(struct dasd_ccw_req * erp) struct dasd_device *device = erp->startdev; - /* - * In some cases the 'File Protected' error might be expected and - * log messages shouldn't be written then. - * Check if the according suppress bit is set. - */ - if (!test_bit(DASD_CQR_SUPPRESS_FP, &erp->flags)) - dev_err(&device->cdev->dev, - "Accessing the DASD failed because of a hardware error\n"); + dev_err(&device->cdev->dev, + "Accessing the DASD failed because of a hardware error\n"); return dasd_3990_erp_cleanup(erp, DASD_CQR_FAILED); diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index 9388b5c383ca..90b106408992 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -2275,6 +2275,7 @@ dasd_eckd_analysis_ccw(struct dasd_device *device) cqr->status = DASD_CQR_FILLED; /* Set flags to suppress output for expected errors */ set_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags); + set_bit(DASD_CQR_SUPPRESS_IT, &cqr->flags); return cqr; } @@ -2556,7 +2557,6 @@ dasd_eckd_build_check_tcw(struct dasd_device *base, struct format_data_t *fdata, cqr->buildclk = get_tod_clock(); cqr->status = DASD_CQR_FILLED; /* Set flags to suppress output for expected errors */ - set_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags); set_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags); return cqr; @@ -4130,8 +4130,6 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single( /* Set flags to suppress output for expected errors */ if (dasd_eckd_is_ese(basedev)) { - set_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags); - set_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags); set_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags); } @@ -4633,9 +4631,8 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_tpm_track( /* Set flags to suppress output for expected errors */ if (dasd_eckd_is_ese(basedev)) { - set_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags); - set_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags); set_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags); + set_bit(DASD_CQR_SUPPRESS_IT, &cqr->flags); } return cqr; @@ -5780,36 +5777,32 @@ static void dasd_eckd_dump_sense(struct dasd_device *device, { u8 *sense = dasd_get_sense(irb); - if (scsw_is_tm(&irb->scsw)) { - /* - * In some cases the 'File Protected' or 'Incorrect Length' - * error might be expected and log messages shouldn't be written - * then. Check if the according suppress bit is set. - */ - if (sense && (sense[1] & SNS1_FILE_PROTECTED) && - test_bit(DASD_CQR_SUPPRESS_FP, &req->flags)) - return; - if (scsw_cstat(&irb->scsw) == 0x40 && - test_bit(DASD_CQR_SUPPRESS_IL, &req->flags)) - return; + /* + * In some cases certain errors might be expected and + * log messages shouldn't be written then. + * Check if the according suppress bit is set. + */ + if (sense && (sense[1] & SNS1_INV_TRACK_FORMAT) && + !(sense[2] & SNS2_ENV_DATA_PRESENT) && + test_bit(DASD_CQR_SUPPRESS_IT, &req->flags)) + return; + if (sense && sense[0] & SNS0_CMD_REJECT && + test_bit(DASD_CQR_SUPPRESS_CR, &req->flags)) + return; + + if (sense && sense[1] & SNS1_NO_REC_FOUND && + test_bit(DASD_CQR_SUPPRESS_NRF, &req->flags)) + return; + + if (scsw_cstat(&irb->scsw) == 0x40 && + test_bit(DASD_CQR_SUPPRESS_IL, &req->flags)) + return; + + if (scsw_is_tm(&irb->scsw)) dasd_eckd_dump_sense_tcw(device, req, irb); - } else { - /* - * In some cases the 'Command Reject' or 'No Record Found' - * error might be expected and log messages shouldn't be - * written then. Check if the according suppress bit is set. - */ - if (sense && sense[0] & SNS0_CMD_REJECT && - test_bit(DASD_CQR_SUPPRESS_CR, &req->flags)) - return; - - if (sense && sense[1] & SNS1_NO_REC_FOUND && - test_bit(DASD_CQR_SUPPRESS_NRF, &req->flags)) - return; - + else dasd_eckd_dump_sense_ccw(device, req, irb); - } } static int dasd_eckd_reload_device(struct dasd_device *device) diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index e5f40536b425..81cfb5c89681 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -196,7 +196,7 @@ struct dasd_ccw_req { * The following flags are used to suppress output of certain errors. */ #define DASD_CQR_SUPPRESS_NRF 4 /* Suppress 'No Record Found' error */ -#define DASD_CQR_SUPPRESS_FP 5 /* Suppress 'File Protected' error*/ +#define DASD_CQR_SUPPRESS_IT 5 /* Suppress 'Invalid Track' error*/ #define DASD_CQR_SUPPRESS_IL 6 /* Suppress 'Incorrect Length' error */ #define DASD_CQR_SUPPRESS_CR 7 /* Suppress 'Command Reject' error */ From c916ca35308d3187c9928664f9be249b22a3a701 Mon Sep 17 00:00:00 2001 From: Yu Kuai Date: Sat, 3 Aug 2024 17:11:37 +0800 Subject: [PATCH 3/4] md/raid1: Fix data corruption for degraded array with slow disk MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit read_balance() will avoid reading from slow disks as much as possible, however, if valid data only lands in slow disks, and a new normal disk is still in recovery, unrecovered data can be read: raid1_read_request read_balance raid1_should_read_first -> return false choose_best_rdev -> normal disk is not recovered, return -1 choose_bb_rdev -> missing the checking of recovery, return the normal disk -> read unrecovered data Root cause is that the checking of recovery is missing in choose_bb_rdev(). Hence add such checking to fix the problem. Also fix similar problem in choose_slow_rdev(). Cc: stable@vger.kernel.org Fixes: 9f3ced792203 ("md/raid1: factor out choose_bb_rdev() from read_balance()") Fixes: dfa8ecd167c1 ("md/raid1: factor out choose_slow_rdev() from read_balance()") Reported-and-tested-by: Mateusz Jończyk Closes: https://lore.kernel.org/all/9952f532-2554-44bf-b906-4880b2e88e3a@o2.pl/ Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20240803091137.3197008-1-yukuai1@huaweicloud.com Signed-off-by: Song Liu --- drivers/md/raid1.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 7acfe7c9dc8d..761989d67906 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -617,6 +617,12 @@ static int choose_first_rdev(struct r1conf *conf, struct r1bio *r1_bio, return -1; } +static bool rdev_in_recovery(struct md_rdev *rdev, struct r1bio *r1_bio) +{ + return !test_bit(In_sync, &rdev->flags) && + rdev->recovery_offset < r1_bio->sector + r1_bio->sectors; +} + static int choose_bb_rdev(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors) { @@ -635,6 +641,7 @@ static int choose_bb_rdev(struct r1conf *conf, struct r1bio *r1_bio, rdev = conf->mirrors[disk].rdev; if (!rdev || test_bit(Faulty, &rdev->flags) || + rdev_in_recovery(rdev, r1_bio) || test_bit(WriteMostly, &rdev->flags)) continue; @@ -673,7 +680,8 @@ static int choose_slow_rdev(struct r1conf *conf, struct r1bio *r1_bio, rdev = conf->mirrors[disk].rdev; if (!rdev || test_bit(Faulty, &rdev->flags) || - !test_bit(WriteMostly, &rdev->flags)) + !test_bit(WriteMostly, &rdev->flags) || + rdev_in_recovery(rdev, r1_bio)) continue; /* there are no bad blocks, we can use this disk */ @@ -733,9 +741,7 @@ static bool rdev_readable(struct md_rdev *rdev, struct r1bio *r1_bio) if (!rdev || test_bit(Faulty, &rdev->flags)) return false; - /* still in recovery */ - if (!test_bit(In_sync, &rdev->flags) && - rdev->recovery_offset < r1_bio->sector + r1_bio->sectors) + if (rdev_in_recovery(rdev, r1_bio)) return false; /* don't read from slow disk unless have to */ From b313a8c835516bdda85025500be866ac8a74e022 Mon Sep 17 00:00:00 2001 From: Li Lingfeng Date: Thu, 15 Aug 2024 10:47:36 +0800 Subject: [PATCH 4/4] block: Fix lockdep warning in blk_mq_mark_tag_wait Lockdep reported a warning in Linux version 6.6: [ 414.344659] ================================ [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.356863] scsi_io_completion+0x177/0x1610 [ 414.357379] scsi_complete+0x12f/0x260 [ 414.357856] blk_complete_reqs+0xba/0xf0 [ 414.358338] __do_softirq+0x1b0/0x7a2 [ 414.358796] irq_exit_rcu+0x14b/0x1a0 [ 414.359262] sysvec_call_function_single+0xaf/0xc0 [ 414.359828] asm_sysvec_call_function_single+0x1a/0x20 [ 414.360426] default_idle+0x1e/0x30 [ 414.360873] default_idle_call+0x9b/0x1f0 [ 414.361390] do_idle+0x2d2/0x3e0 [ 414.361819] cpu_startup_entry+0x55/0x60 [ 414.362314] start_secondary+0x235/0x2b0 [ 414.362809] secondary_startup_64_no_verify+0x18f/0x19b [ 414.363413] irq event stamp: 428794 [ 414.363825] hardirqs last enabled at (428793): [] ktime_get+0x1dc/0x200 [ 414.364694] hardirqs last disabled at (428794): [] _raw_spin_lock_irq+0x47/0x50 [ 414.365629] softirqs last enabled at (428444): [] __do_softirq+0x540/0x7a2 [ 414.366522] softirqs last disabled at (428419): [] irq_exit_rcu+0x14b/0x1a0 [ 414.367425] other info that might help us debug this: [ 414.368194] Possible unsafe locking scenario: [ 414.368900] CPU0 [ 414.369225] ---- [ 414.369548] lock(&sbq->ws[i].wait); [ 414.370000] [ 414.370342] lock(&sbq->ws[i].wait); [ 414.370802] *** DEADLOCK *** [ 414.371569] 5 locks held by kworker/u10:3/1152: [ 414.372088] #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0 [ 414.373180] #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0 [ 414.374384] #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00 [ 414.375342] #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.376377] #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0 [ 414.378607] stack backtrace: [ 414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda #6 [ 414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 414.381177] Workqueue: writeback wb_workfn (flush-253:0) [ 414.381805] Call Trace: [ 414.382136] [ 414.382429] dump_stack_lvl+0x91/0xf0 [ 414.382884] mark_lock_irq+0xb3b/0x1260 [ 414.383367] ? __pfx_mark_lock_irq+0x10/0x10 [ 414.383889] ? stack_trace_save+0x8e/0xc0 [ 414.384373] ? __pfx_stack_trace_save+0x10/0x10 [ 414.384903] ? graph_lock+0xcf/0x410 [ 414.385350] ? save_trace+0x3d/0xc70 [ 414.385808] mark_lock.part.20+0x56d/0xa90 [ 414.386317] mark_held_locks+0xb0/0x110 [ 414.386791] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.387320] lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.387901] ? _raw_spin_unlock_irq+0x28/0x50 [ 414.388422] trace_hardirqs_on+0x58/0x100 [ 414.388917] _raw_spin_unlock_irq+0x28/0x50 [ 414.389422] __blk_mq_tag_busy+0x1d6/0x2a0 [ 414.389920] __blk_mq_get_driver_tag+0x761/0x9f0 [ 414.390899] blk_mq_dispatch_rq_list+0x1780/0x1ee0 [ 414.391473] ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10 [ 414.392070] ? sbitmap_get+0x2b8/0x450 [ 414.392533] ? __blk_mq_get_driver_tag+0x210/0x9f0 [ 414.393095] __blk_mq_sched_dispatch_requests+0xd99/0x1690 [ 414.393730] ? elv_attempt_insert_merge+0x1b1/0x420 [ 414.394302] ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10 [ 414.394970] ? lock_acquire+0x18d/0x460 [ 414.395456] ? blk_mq_run_hw_queue+0x637/0xa00 [ 414.395986] ? __pfx_lock_acquire+0x10/0x10 [ 414.396499] blk_mq_sched_dispatch_requests+0x109/0x190 [ 414.397100] blk_mq_run_hw_queue+0x66e/0xa00 [ 414.397616] blk_mq_flush_plug_list.part.17+0x614/0x2030 [ 414.398244] ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10 [ 414.398897] ? writeback_sb_inodes+0x241/0xcc0 [ 414.399429] blk_mq_flush_plug_list+0x65/0x80 [ 414.399957] __blk_flush_plug+0x2f1/0x530 [ 414.400458] ? __pfx___blk_flush_plug+0x10/0x10 [ 414.400999] blk_finish_plug+0x59/0xa0 [ 414.401467] wb_writeback+0x7cc/0x920 [ 414.401935] ? __pfx_wb_writeback+0x10/0x10 [ 414.402442] ? mark_held_locks+0xb0/0x110 [ 414.402931] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.403462] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.404062] wb_workfn+0x2b3/0xcf0 [ 414.404500] ? __pfx_wb_workfn+0x10/0x10 [ 414.404989] process_scheduled_works+0x432/0x13f0 [ 414.405546] ? __pfx_process_scheduled_works+0x10/0x10 [ 414.406139] ? do_raw_spin_lock+0x101/0x2a0 [ 414.406641] ? assign_work+0x19b/0x240 [ 414.407106] ? lock_is_held_type+0x9d/0x110 [ 414.407604] worker_thread+0x6f2/0x1160 [ 414.408075] ? __kthread_parkme+0x62/0x210 [ 414.408572] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.409168] ? __kthread_parkme+0x13c/0x210 [ 414.409678] ? __pfx_worker_thread+0x10/0x10 [ 414.410191] kthread+0x33c/0x440 [ 414.410602] ? __pfx_kthread+0x10/0x10 [ 414.411068] ret_from_fork+0x4d/0x80 [ 414.411526] ? __pfx_kthread+0x10/0x10 [ 414.411993] ret_from_fork_asm+0x1b/0x30 [ 414.412489] When interrupt is turned on while a lock holding by spin_lock_irq it throws a warning because of potential deadlock. blk_mq_prep_dispatch_rq blk_mq_get_driver_tag __blk_mq_get_driver_tag __blk_mq_alloc_driver_tag blk_mq_tag_busy -> tag is already busy // failed to get driver tag blk_mq_mark_tag_wait spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait) __add_wait_queue(wq, wait) -> wait queue active blk_mq_get_driver_tag __blk_mq_tag_busy -> 1) tag must be idle, which means there can't be inflight IO spin_lock_irq(&tags->lock) -> lock B (hctx->tags) spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally -> 2) context must be preempt by IO interrupt to trigger deadlock. As shown above, the deadlock is not possible in theory, but the warning still need to be fixed. Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq. Fixes: 4f1731df60f9 ("blk-mq: fix potential io hang by wrong 'wake_batch'") Signed-off-by: Li Lingfeng Reviewed-by: Ming Lei Reviewed-by: Yu Kuai Reviewed-by: Bart Van Assche Link: https://lore.kernel.org/r/20240815024736.2040971-1-lilingfeng@huaweicloud.com Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index cc57e2dd9a0b..2cafcf11ee8b 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -38,6 +38,7 @@ static void blk_mq_update_wake_batch(struct blk_mq_tags *tags, void __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) { unsigned int users; + unsigned long flags; struct blk_mq_tags *tags = hctx->tags; /* @@ -56,11 +57,11 @@ void __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) return; } - spin_lock_irq(&tags->lock); + spin_lock_irqsave(&tags->lock, flags); users = tags->active_queues + 1; WRITE_ONCE(tags->active_queues, users); blk_mq_update_wake_batch(tags, users); - spin_unlock_irq(&tags->lock); + spin_unlock_irqrestore(&tags->lock, flags); } /*