From 8fae268b40f5191227ae7050a99cb2cf1b914ddd Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Fri, 4 Jan 2019 15:04:33 -0700 Subject: [PATCH] nvme-pci: rerun irq setup on IO queue init errors If the driver is unable to create a subset of IO queues for any reason, the read/write and polled queue sets will not match the actual allocated hardware contexts. This leaves gaps in the CPU affinity mappings and causes the following kernel panic after blk_mq_map_queue_type() returns a NULL hctx. BUG: unable to handle kernel NULL pointer dereference at 0000000000000198 #PF error: [normal kernel read fault] PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 64 PID: 1171 Comm: kworker/u259:1 Not tainted 4.20.0+ #241 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014 Workqueue: nvme-wq nvme_scan_work [nvme_core] RIP: 0010:blk_mq_init_allocated_queue+0x2d9/0x440 RSP: 0018:ffffb1bf0abc3cd0 EFLAGS: 00010286 RAX: 000000000000001f RBX: ffff8ea744cf0718 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 000000000000007c RDI: ffffffff9109a820 RBP: ffff8ea7565f7008 R08: 000000000000001f R09: 000000000000003f R10: ffffb1bf0abc3c00 R11: 0000000000000000 R12: 000000000001d008 R13: ffff8ea7565f7008 R14: 000000000000003f R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8ea757200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000198 CR3: 0000000013058000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: blk_mq_init_queue+0x35/0x60 nvme_validate_ns+0xc6/0x7c0 [nvme_core] ? nvme_identify_ctrl.isra.56+0x7e/0xc0 [nvme_core] nvme_scan_work+0xc8/0x340 [nvme_core] ? __wake_up_common+0x6d/0x120 ? try_to_wake_up+0x55/0x410 process_one_work+0x1e9/0x3d0 worker_thread+0x2d/0x3d0 ? process_one_work+0x3d0/0x3d0 kthread+0x111/0x130 ? kthread_park+0x90/0x90 ret_from_fork+0x1f/0x30 Modules linked in: nvme nvme_core serio_raw CR2: 0000000000000198 Fix by re-running the interrupt vector setup from scratch using a reduced count that may be successful until the created queues matches the irq affinity plus polling queue sets. Signed-off-by: Keith Busch Reviewed-by: Sagi Grimberg Reviewed-by: Ming Lei Signed-off-by: Christoph Hellwig --- drivers/nvme/host/pci.c | 50 +++++++++++++++++++++++++++++++++++-------------- 1 file changed, 36 insertions(+), 14 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index efe46f5..f891eb5 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -95,6 +95,7 @@ struct nvme_dev; struct nvme_queue; static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown); +static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode); /* * Represents an NVM Express device. Each nvme_dev is a PCI function. @@ -1420,6 +1421,14 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) return 0; } +static void nvme_suspend_io_queues(struct nvme_dev *dev) +{ + int i; + + for (i = dev->ctrl.queue_count - 1; i > 0; i--) + nvme_suspend_queue(&dev->queues[i]); +} + static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown) { struct nvme_queue *nvmeq = &dev->queues[0]; @@ -2134,6 +2143,12 @@ static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues) return result; } +static void nvme_disable_io_queues(struct nvme_dev *dev) +{ + if (__nvme_disable_io_queues(dev, nvme_admin_delete_sq)) + __nvme_disable_io_queues(dev, nvme_admin_delete_cq); +} + static int nvme_setup_io_queues(struct nvme_dev *dev) { struct nvme_queue *adminq = &dev->queues[0]; @@ -2170,6 +2185,7 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) } while (1); adminq->q_db = dev->dbs; + retry: /* Deregister the admin queue's interrupt */ pci_free_irq(pdev, 0, adminq); @@ -2187,25 +2203,34 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) result = max(result - 1, 1); dev->max_qid = result + dev->io_queues[HCTX_TYPE_POLL]; - dev_info(dev->ctrl.device, "%d/%d/%d default/read/poll queues\n", - dev->io_queues[HCTX_TYPE_DEFAULT], - dev->io_queues[HCTX_TYPE_READ], - dev->io_queues[HCTX_TYPE_POLL]); - /* * Should investigate if there's a performance win from allocating * more queues than interrupt vectors; it might allow the submission * path to scale better, even if the receive path is limited by the * number of interrupts. */ - result = queue_request_irq(adminq); if (result) { adminq->cq_vector = -1; return result; } set_bit(NVMEQ_ENABLED, &adminq->flags); - return nvme_create_io_queues(dev); + + result = nvme_create_io_queues(dev); + if (result || dev->online_queues < 2) + return result; + + if (dev->online_queues - 1 < dev->max_qid) { + nr_io_queues = dev->online_queues - 1; + nvme_disable_io_queues(dev); + nvme_suspend_io_queues(dev); + goto retry; + } + dev_info(dev->ctrl.device, "%d/%d/%d default/read/poll queues\n", + dev->io_queues[HCTX_TYPE_DEFAULT], + dev->io_queues[HCTX_TYPE_READ], + dev->io_queues[HCTX_TYPE_POLL]); + return 0; } static void nvme_del_queue_end(struct request *req, blk_status_t error) @@ -2250,7 +2275,7 @@ static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode) return 0; } -static bool nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode) +static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode) { int nr_queues = dev->online_queues - 1, sent = 0; unsigned long timeout; @@ -2411,7 +2436,6 @@ static void nvme_pci_disable(struct nvme_dev *dev) static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown) { - int i; bool dead = true; struct pci_dev *pdev = to_pci_dev(dev->dev); @@ -2438,13 +2462,11 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown) nvme_stop_queues(&dev->ctrl); if (!dead && dev->ctrl.queue_count > 0) { - if (nvme_disable_io_queues(dev, nvme_admin_delete_sq)) - nvme_disable_io_queues(dev, nvme_admin_delete_cq); + nvme_disable_io_queues(dev); nvme_disable_admin_queue(dev, shutdown); } - for (i = dev->ctrl.queue_count - 1; i >= 0; i--) - nvme_suspend_queue(&dev->queues[i]); - + nvme_suspend_io_queues(dev); + nvme_suspend_queue(&dev->queues[0]); nvme_pci_disable(dev); blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl); -- 2.7.4