From ecbcdf0c81265f7f780b588eed77fa933fd79f68 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Wed, 12 Aug 2020 17:24:44 -0600 Subject: nvme: Use spin_lock_irq() when taking the ctrl->lock When locking the ctrl->lock spinlock IRQs need to be disabled to avoid a dead lock. The new spin_lock() calls recently added produce the following lockdep warning when running the blktest nvme/003: ================================ WARNING: inconsistent lock state -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/2/22 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff888276a8c4c0 (&ctrl->lock){+.?.}-{2:2}, at: nvme_keep_alive_end_io+0x50/0xc0 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x164/0x500 _raw_spin_lock+0x28/0x40 nvme_get_effects_log+0x37/0x1c0 nvme_init_identify+0x9e4/0x14f0 nvme_reset_work+0xadd/0x2360 process_one_work+0x66b/0xb70 worker_thread+0x6e/0x6c0 kthread+0x1e7/0x210 ret_from_fork+0x22/0x30 irq event stamp: 1449221 hardirqs last enabled at (1449220): [] ktime_get+0xf9/0x140 hardirqs last disabled at (1449221): [] _raw_spin_lock_irqsave+0x25/0x60 softirqs last enabled at (1449210): [] __do_softirq+0x447/0x595 softirqs last disabled at (1449215): [] run_ksoftirqd+0x35/0x50 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&ctrl->lock); lock(&ctrl->lock); *** DEADLOCK *** no locks held by ksoftirqd/2/22. stack backtrace: CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 5.8.0-rc4-eid-vmlocalyes-dbg-00157-g7236657c6b3a #1450 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack+0xc8/0x11a print_usage_bug.cold.63+0x235/0x23e mark_lock+0xa9c/0xcf0 __lock_acquire+0xd9a/0x2b50 lock_acquire+0x164/0x500 _raw_spin_lock_irqsave+0x40/0x60 nvme_keep_alive_end_io+0x50/0xc0 blk_mq_end_request+0x158/0x210 nvme_complete_rq+0x146/0x500 nvme_loop_complete_rq+0x26/0x30 [nvme_loop] blk_done_softirq+0x187/0x1e0 __do_softirq+0x118/0x595 run_ksoftirqd+0x35/0x50 smpboot_thread_fn+0x1d3/0x310 kthread+0x1e7/0x210 ret_from_fork+0x22/0x30 Fixes: be93e87e7802 ("nvme: support for multiple Command Sets Supported and Effects log pages") Signed-off-by: Logan Gunthorpe Reviewed-by: Keith Busch Tested-by: Chaitanya Kulkarni Reviewed-by: Chaitanya Kulkarni Signed-off-by: Sagi Grimberg Signed-off-by: Jens Axboe --- drivers/nvme/host/core.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/nvme') diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 88cff309d8e4..466c591c05e9 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2965,14 +2965,14 @@ static struct nvme_cel *nvme_find_cel(struct nvme_ctrl *ctrl, u8 csi) { struct nvme_cel *cel, *ret = NULL; - spin_lock(&ctrl->lock); + spin_lock_irq(&ctrl->lock); list_for_each_entry(cel, &ctrl->cels, entry) { if (cel->csi == csi) { ret = cel; break; } } - spin_unlock(&ctrl->lock); + spin_unlock_irq(&ctrl->lock); return ret; } @@ -2999,9 +2999,9 @@ static int nvme_get_effects_log(struct nvme_ctrl *ctrl, u8 csi, cel->csi = csi; - spin_lock(&ctrl->lock); + spin_lock_irq(&ctrl->lock); list_add_tail(&cel->entry, &ctrl->cels); - spin_unlock(&ctrl->lock); + spin_unlock_irq(&ctrl->lock); out: *log = &cel->log; return 0; -- cgit v1.2.3