On Mon, 2023-01-16 at 15:59 +0100, Steffen Maier wrote: > Hi all, > > since a few days/weeks, we sometimes see below alua and sleep related > kernel > BUG and WARNING (with panic_on_warn) in our CI. > > It reminds me of > [PATCH 0/2] Rework how the ALUA driver calls scsi_device_put() > https://lore.kernel.org/linux-scsi/166986602290.2101055.17397734326843853911.b4-ty@xxxxxxxxxx/ > > which I thought was the fix and went into 6.2-rc(1?) on 2022-12-14 > with > [GIT PULL] first round of SCSI updates for the 6.1+ merge window > https://lore.kernel.org/linux-scsi/b2e824bbd1e40da64d2d01657f2f7a67b98919fb.camel@xxxxxxxxxxxxxxxxxxxxx/T/#u > That was the fix for the code path alua_check_vpd()->alua_rtpg_queue() ->scsi_device_put(), where alua_rtpg_queue() was called while obviously holding a lock. The call chain in your case is different. But AFAICS Bart's original fix for the BUG, "scsi: alua: Fix alua_rtpg_queue()" (https://lore.kernel.org/linux-scsi/20221115224903.2325529-1-bvanassche@xxxxxxx/) would also not solve your issue, because it simply moves the scsi_device_put() to the caller, alua_check(), which can't sleep, either. [ 4569.046131] [<000003ff7fb9c874>] alua_rtpg_queue+0x3c/0x98 [scsi_dh_alua] [ 4569.046146] [<000003ff7fb9cfb2>] alua_check+0x122/0x250 [scsi_dh_alua] [ 4569.046167] [<000003ff7fb9d562>] alua_check_sense+0x172/0x228 [scsi_dh_alua] [ 4569.046179] [<000000017e96b3e2>] scsi_check_sense+0x8a/0x2e0 [ 4569.046191] [<000000017e96e4b6>] scsi_decide_disposition+0x286/0x298 [ 4569.046201] [<000000017e972bca>] scsi_complete+0x6a/0x108 [ 4569.046212] [<000000017e746906>] blk_complete_reqs+0x6e/0x88 [ 4569.046227] [<000000017ed3830e>] __do_softirq+0x13e/0x6b8 AFAICS, it comes down to the fact that the assertion in the commit message of f93ed747e2c7 ("scsi: core: Release SCSI devices synchronously"): "All upstream scsi_device_put() calls happen from thread context." turns out to be false for the alua code. Can we simply defer the scsi_device_put() to a workqueue? Regards, Martin > Due to limited history, I cannot tell exactly when problems started > and whether > it really correlates to above. > > Test workload are all kinds of coverage tests for zfcp recovery > including scsi > device removal and/or rescan. > > [ 4569.045992] BUG: sleeping function called from invalid context at > drivers/scsi/device_handler/scsi_dh_alua.c:992 > [ 4569.046003] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: > 0, name: > swapper/8 > [ 4569.046013] preempt_count: 101, expected: 0 > [ 4569.046023] RCU nest depth: 0, expected: 0 > [ 4569.046033] no locks held by swapper/8/0. > [ 4569.046042] Preemption disabled at: > [ 4569.046046] [<000000017e27ce4e>] > __slab_alloc.constprop.0+0x36/0xb8 > [ 4569.046072] CPU: 8 PID: 0 Comm: swapper/8 Tainted: G W > 6.2.0-20230114.rc3.git0.46e26dd43df0.300.fc37.s390x+debug #1 > [ 4569.046084] Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) > [ 4569.046094] Call Trace: > [ 4569.046102] [<000000017ed21bcc>] dump_stack_lvl+0xac/0x100 > [ 4569.046118] [<000000017df9192c>] __might_resched+0x284/0x2c8 > [ 4569.046131] [<000003ff7fb9c874>] alua_rtpg_queue+0x3c/0x98 > [scsi_dh_alua] > [ 4569.046146] [<000003ff7fb9cfb2>] alua_check+0x122/0x250 > [scsi_dh_alua] > [ 4569.046167] [<000003ff7fb9d562>] alua_check_sense+0x172/0x228 > [scsi_dh_alua] > [ 4569.046179] [<000000017e96b3e2>] scsi_check_sense+0x8a/0x2e0 > [ 4569.046191] [<000000017e96e4b6>] > scsi_decide_disposition+0x286/0x298 > [ 4569.046201] [<000000017e972bca>] scsi_complete+0x6a/0x108 > [ 4569.046212] [<000000017e746906>] blk_complete_reqs+0x6e/0x88 > [ 4569.046227] [<000000017ed3830e>] __do_softirq+0x13e/0x6b8 > [ 4569.046238] [<000000017df57902>] __irq_exit_rcu+0x14a/0x170 > [ 4569.046264] [<000000017df58472>] irq_exit_rcu+0x22/0x50 > [ 4569.046275] [<000000017ed2242a>] do_ext_irq+0x10a/0x1d0 > [ 4569.046286] [<000000017ed36156>] ext_int_handler+0xd6/0x110 > [ 4569.046296] [<000000017ed362e6>] psw_idle_exit+0x0/0xa > [ 4569.046307] ([<000000017defc5da>] arch_cpu_idle+0x52/0xe0) > [ 4569.046318] [<000000017ed34744>] default_idle_call+0x84/0xd0 > [ 4569.046329] [<000000017dfbe4cc>] do_idle+0xfc/0x1b8 > [ 4569.046340] [<000000017dfbe80e>] cpu_startup_entry+0x36/0x40 > [ 4569.046350] [<000000017df11964>] smp_start_secondary+0x14c/0x160 > [ 4569.046371] [<000000017ed3658e>] restart_int_handler+0x6e/0x90 > [ 4569.046381] no locks held by swapper/8/0. > > Above occurs a few times until it finally ends with: > > [ 4760.865496] device-mapper: multipath: 251:6: Reinstating path > 8:176. > [ 4760.867398] sd 4:0:0:1083719810: Power-on or device reset occurred > [ 4760.867445] sd 4:0:0:1083719810: [sde] tag#1224 Done: > ADD_TO_MLQUEUE Result: > hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s > [ 4760.867469] sd 4:0:0:1083719810: [sde] tag#1224 CDB: Test Unit > Ready 00 00 > 00 00 00 00 > [ 4760.867493] sd 4:0:0:1083719810: [sde] tag#1224 Sense Key : Unit > Attention > [current] > [ 4760.867515] sd 4:0:0:1083719810: [sde] tag#1224 Add. Sense: Power > on, reset, > or bus device reset occurred > [ 4760.878066] sd 4:0:0:1083719813: Power-on or device reset occurred > [ 4760.878096] ------------[ cut here ]------------ > [ 4760.878107] do not call blocking ops when !TASK_RUNNING; state=2 > set at > [<000000017ed2c0fa>] __wait_for_common+0xa2/0x240 > [ 4760.878132] WARNING: CPU: 3 PID: 165738 at > kernel/sched/core.c:9908 > __might_sleep+0x7c/0x98 > [ 4760.878147] Modules linked in: af_iucv kvm algif_hash af_alg > nft_fib_inet > nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 > nf_reject_ipv6 > nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 > nf_defrag_ipv4 ip_set nf_tables nfnetlink sunrpc vfio_ccw mdev > vfio_iommu_type1 > vfio sch_fq_codel ip6_tables ip_tables x_tables configfs > dm_service_time > ghash_s390 prng chacha_s390 libchacha aes_s390 des_s390 libdes > sha512_s390 > sha256_s390 sha1_s390 sha_common zfcp scsi_transport_fc dm_mirror > dm_region_hash dm_log scsi_dh_rdac scsi_dh_emc scsi_dh_alua pkey > zcrypt > rng_core dm_multipath autofs4 > [ 4760.878456] CPU: 3 PID: 165738 Comm: kworker/3:0 Tainted: G > W > 6.2.0-20230114.rc3.git0.46e26dd43df0.300.fc37.s390x+debug #1 > [ 4760.878478] Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) > [ 4760.878489] Workqueue: kaluad alua_rtpg_work [scsi_dh_alua] > [ 4760.878509] Krnl PSW : 0704d00180000000 000000017df919f0 > (__might_sleep+0x80/0x98) > [ 4760.878542] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 > CC:1 PM:0 > RI:0 EA:3 > [ 4760.878560] Krnl GPRS: c0000000ffffbfff 0000000080000101 > 000000000000006d > 000000017f198e94 > [ 4760.878573] 00000380002739f8 00000380002739f0 > 0000000000000000 > 000000017f7bca48 > [ 4760.878586] 0000000000000001 0000000000000000 > 00000000000003e0 > 000003ff7fb9f1bc > [ 4760.878599] 00000000827eb100 0000000000000101 > 000000017df919ec > 0000038000273b88 > [ 4760.878620] Krnl Code: 000000017df919e0: > c020008c1da3 larl %r2,000000017f115526 > 000000017df919e6: c0e5006bb91d brasl > %r14,000000017ed08c20 > #000000017df919ec: > af000000 mc 0,0 > >000000017df919f0: > a7490000 lghi %r4,0 > 000000017df919f4: > b904003a lgr %r3,%r10 > 000000017df919f8: > b904002b lgr %r2,%r11 > 000000017df919fc: > ebaff0a00004 lmg %r10,%r15,160(%r15) > 000000017df91a02: > c0f4fffffe53 brcl 15,000000017df916a8 > [ 4760.878692] Call Trace: > [ 4760.878703] [<000000017df919f0>] __might_sleep+0x80/0x98 > [ 4760.878716] ([<000000017df919ec>] __might_sleep+0x7c/0x98) > [ 4760.878728] [<000003ff7fb9c874>] alua_rtpg_queue+0x3c/0x98 > [scsi_dh_alua] > [ 4760.878743] [<000003ff7fb9cfb2>] alua_check+0x122/0x250 > [scsi_dh_alua] > [ 4760.878761] [<000003ff7fb9d562>] alua_check_sense+0x172/0x228 > [scsi_dh_alua] > [ 4760.878775] [<000000017e96b3e2>] scsi_check_sense+0x8a/0x2e0 > [ 4760.878788] [<000000017e96e4b6>] > scsi_decide_disposition+0x286/0x298 > [ 4760.878802] [<000000017e972bca>] scsi_complete+0x6a/0x108 > [ 4760.878815] [<000000017e746906>] blk_complete_reqs+0x6e/0x88 > [ 4760.878837] [<000000017ed3830e>] __do_softirq+0x13e/0x6b8 > [ 4760.878852] [<000000017df57902>] __irq_exit_rcu+0x14a/0x170 > [ 4760.878866] [<000000017df58472>] irq_exit_rcu+0x22/0x50 > [ 4760.878880] [<000000017ed223da>] do_ext_irq+0xba/0x1d0 > [ 4760.878896] [<000000017ed36156>] ext_int_handler+0xd6/0x110 > [ 4760.878909] [<000000017ed34fbe>] > _raw_spin_unlock_irqrestore+0x86/0xc0 > [ 4760.878928] ([<000000017ed34fae>] > _raw_spin_unlock_irqrestore+0x76/0xc0) > [ 4760.878941] [<000000017e033e66>] __mod_timer+0x2d6/0x408 > [ 4760.878955] [<000000017ed33864>] schedule_timeout+0xc4/0x168 > [ 4760.878969] [<000000017ed2ac62>] io_schedule_timeout+0x5a/0x80 > [ 4760.878983] [<000000017ed2c12e>] __wait_for_common+0xd6/0x240 > [ 4760.878997] [<000000017e7479a6>] blk_execute_rq+0x126/0x1f8 > [ 4760.879011] [<000000017e970722>] __scsi_execute+0x112/0x260 > [ 4760.879024] [<000003ff7fb9d750>] alua_rtpg+0x138/0xb10 > [scsi_dh_alua] > [ 4760.879038] [<000003ff7fb9e3e4>] alua_rtpg_work+0x2bc/0x4e0 > [scsi_dh_alua] > [ 4760.879053] [<000000017df78300>] process_one_work+0x310/0x730 > [ 4760.879069] [<000000017df78782>] worker_thread+0x62/0x420 > [ 4760.879109] [<000000017df83bc4>] kthread+0x13c/0x150 > [ 4760.879124] [<000000017defb930>] __ret_from_fork+0x40/0x58 > [ 4760.879138] [<000000017ed35eda>] ret_from_fork+0xa/0x40 > [ 4760.879152] 2 locks held by kworker/3:0/165738: > [ 4760.879165] #0: 000000008c7b5948 ((wq_completion)kaluad){+.+.}- > {0:0}, at: > process_one_work+0x232/0x730 > [ 4760.879210] #1: 0000038001177dc8 > ((work_completion)(&(&pg->rtpg_work)->work)){+.+.}-{0:0}, at: > process_one_work+0x232/0x730 > [ 4760.879249] Last Breaking-Event-Address: > [ 4760.879266] [<000000017e8c6dd0>] > __s390_indirect_jump_r14+0x0/0x10 > [ 4760.879283] Kernel panic - not syncing: kernel: panic_on_warn set > ... > >
