BMC/Intel-BMC/linux.git/drivers/nvme/host/multipath.c, branch dev-5.2

nvme-multipath: fix possible I/O hang when paths are updated

2019-09-10T09:35:21+00:00

[ Upstream commit 504db087aaccdb32af61539916409f7dca31ceb5 ] nvme_state_set_live() making a path available triggers requeue_work in order to resubmit requests that ended up on requeue_list when no paths were available. This requeue_work may race with concurrent nvme_ns_head_make_request() that do not observe the live path yet. Such concurrent requests may by made by either: - New IO submission. - Requeue_work triggered by nvme_failover_req() or another ana_work. A race may cause requeue_work capture the state of requeue_list before more requests get onto the list. These requests will stay on the list forever unless requeue_work is triggered again. In order to prevent such race, nvme_state_set_live() should synchronize_srcu(&head->srcu) before triggering the requeue_work and prevent nvme_ns_head_make_request referencing an old snapshot of the path list. Reviewed-by: Christoph Hellwig Signed-off-by: Anton Eidelman Signed-off-by: Sagi Grimberg Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

nvme: fix controller removal race with scan work

2019-09-06T08:23:16+00:00

[ Upstream commit 0157ec8dad3c8fc9bc9790f76e0831ffdaf2e7f0 ] With multipath enabled, nvme_scan_work() can read from the device (through nvme_mpath_add_disk()) and hang [1]. However, with fabrics, once ctrl->state is set to NVME_CTRL_DELETING, the reads will hang (see nvmf_check_ready()) and the mpath stack device make_request will block if head->list is not empty. However, when the head->list consistst of only DELETING/DEAD controllers, we should actually not block, but rather fail immediately. In addition, before we go ahead and remove the namespaces, make sure to clear the current path and kick the requeue list so that the request will fast fail upon requeuing. [1]: -- INFO: task kworker/u4:3:166 blocked for more than 120 seconds. Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:3 D 0 166 2 0x80004000 Workqueue: nvme-wq nvme_scan_work Call Trace: __schedule+0x851/0x1400 schedule+0x99/0x210 io_schedule+0x21/0x70 do_read_cache_page+0xa57/0x1330 read_cache_page+0x4a/0x70 read_dev_sector+0xbf/0x380 amiga_partition+0xc4/0x1230 check_partition+0x30f/0x630 rescan_partitions+0x19a/0x980 __blkdev_get+0x85a/0x12f0 blkdev_get+0x2a5/0x790 __device_add_disk+0xe25/0x1250 device_add_disk+0x13/0x20 nvme_mpath_set_live+0x172/0x2b0 nvme_update_ns_ana_state+0x130/0x180 nvme_set_ns_ana_state+0x9a/0xb0 nvme_parse_ana_log+0x1c3/0x4a0 nvme_mpath_add_disk+0x157/0x290 nvme_validate_ns+0x1017/0x1bd0 nvme_scan_work+0x44d/0x6a0 process_one_work+0x7d7/0x1240 worker_thread+0x8e/0xff0 kthread+0x2c3/0x3b0 ret_from_fork+0x35/0x40 INFO: task kworker/u4:1:1034 blocked for more than 120 seconds. Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:1 D 0 1034 2 0x80004000 Workqueue: nvme-delete-wq nvme_delete_ctrl_work Call Trace: __schedule+0x851/0x1400 schedule+0x99/0x210 schedule_timeout+0x390/0x830 wait_for_completion+0x1a7/0x310 __flush_work+0x241/0x5d0 flush_work+0x10/0x20 nvme_remove_namespaces+0x85/0x3d0 nvme_do_delete_ctrl+0xb4/0x1e0 nvme_delete_ctrl_work+0x15/0x20 process_one_work+0x7d7/0x1240 worker_thread+0x8e/0xff0 kthread+0x2c3/0x3b0 ret_from_fork+0x35/0x40 -- Reported-by: Logan Gunthorpe Tested-by: Logan Gunthorpe Reviewed-by: Logan Gunthorpe Reviewed-by: Ming Lei Signed-off-by: Sagi Grimberg Signed-off-by: Sasha Levin

nvme: fix a possible deadlock when passthru commands sent to a multipath device

2019-09-06T08:23:15+00:00

[ Upstream commit b9156daeb1601d69007b7e50efcf89d69d72ec1d ] When the user issues a command with side effects, we will end up freezing the namespace request queue when updating disk info (and the same for the corresponding mpath disk node). However, we are not freezing the mpath node request queue, which means that mpath I/O can still come in and block on blk_queue_enter (called from nvme_ns_head_make_request -> direct_make_request). This is a deadlock, because blk_queue_enter will block until the inner namespace request queue is unfroze, but that process is blocked because the namespace revalidation is trying to update the mpath disk info and freeze its request queue (which will never complete because of the I/O that is blocked on blk_queue_enter). Fix this by freezing all the subsystem nsheads request queues before executing the passthru command. Given that these commands are infrequent we should not worry about this temporary I/O freeze to keep things sane. Here is the matching hang traces: -- [ 374.465002] INFO: task systemd-udevd:17994 blocked for more than 122 seconds. [ 374.472975] Not tainted 5.2.0-rc3-mpdebug+ #42 [ 374.478522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 374.487274] systemd-udevd D 0 17994 1 0x00000000 [ 374.493407] Call Trace: [ 374.496145] __schedule+0x2ef/0x620 [ 374.500047] schedule+0x38/0xa0 [ 374.503569] blk_queue_enter+0x139/0x220 [ 374.507959] ? remove_wait_queue+0x60/0x60 [ 374.512540] direct_make_request+0x60/0x130 [ 374.517219] nvme_ns_head_make_request+0x11d/0x420 [nvme_core] [ 374.523740] ? generic_make_request_checks+0x307/0x6f0 [ 374.529484] generic_make_request+0x10d/0x2e0 [ 374.534356] submit_bio+0x75/0x140 [ 374.538163] ? guard_bio_eod+0x32/0xe0 [ 374.542361] submit_bh_wbc+0x171/0x1b0 [ 374.546553] block_read_full_page+0x1ed/0x330 [ 374.551426] ? check_disk_change+0x70/0x70 [ 374.556008] ? scan_shadow_nodes+0x30/0x30 [ 374.560588] blkdev_readpage+0x18/0x20 [ 374.564783] do_read_cache_page+0x301/0x860 [ 374.569463] ? blkdev_writepages+0x10/0x10 [ 374.574037] ? prep_new_page+0x88/0x130 [ 374.578329] ? get_page_from_freelist+0xa2f/0x1280 [ 374.583688] ? __alloc_pages_nodemask+0x179/0x320 [ 374.588947] read_cache_page+0x12/0x20 [ 374.593142] read_dev_sector+0x2d/0xd0 [ 374.597337] read_lba+0x104/0x1f0 [ 374.601046] find_valid_gpt+0xfa/0x720 [ 374.605243] ? string_nocheck+0x58/0x70 [ 374.609534] ? find_valid_gpt+0x720/0x720 [ 374.614016] efi_partition+0x89/0x430 [ 374.618113] ? string+0x48/0x60 [ 374.621632] ? snprintf+0x49/0x70 [ 374.625339] ? find_valid_gpt+0x720/0x720 [ 374.629828] check_partition+0x116/0x210 [ 374.634214] rescan_partitions+0xb6/0x360 [ 374.638699] __blkdev_reread_part+0x64/0x70 [ 374.643377] blkdev_reread_part+0x23/0x40 [ 374.647860] blkdev_ioctl+0x48c/0x990 [ 374.651956] block_ioctl+0x41/0x50 [ 374.655766] do_vfs_ioctl+0xa7/0x600 [ 374.659766] ? locks_lock_inode_wait+0xb1/0x150 [ 374.664832] ksys_ioctl+0x67/0x90 [ 374.668539] __x64_sys_ioctl+0x1a/0x20 [ 374.672732] do_syscall_64+0x5a/0x1c0 [ 374.676828] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 374.738474] INFO: task nvmeadm:49141 blocked for more than 123 seconds. [ 374.745871] Not tainted 5.2.0-rc3-mpdebug+ #42 [ 374.751419] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 374.760170] nvmeadm D 0 49141 36333 0x00004080 [ 374.766301] Call Trace: [ 374.769038] __schedule+0x2ef/0x620 [ 374.772939] schedule+0x38/0xa0 [ 374.776452] blk_mq_freeze_queue_wait+0x59/0x100 [ 374.781614] ? remove_wait_queue+0x60/0x60 [ 374.786192] blk_mq_freeze_queue+0x1a/0x20 [ 374.790773] nvme_update_disk_info.isra.57+0x5f/0x350 [nvme_core] [ 374.797582] ? nvme_identify_ns.isra.50+0x71/0xc0 [nvme_core] [ 374.804006] __nvme_revalidate_disk+0xe5/0x110 [nvme_core] [ 374.810139] nvme_revalidate_disk+0xa6/0x120 [nvme_core] [ 374.816078] ? nvme_submit_user_cmd+0x11e/0x320 [nvme_core] [ 374.822299] nvme_user_cmd+0x264/0x370 [nvme_core] [ 374.827661] nvme_dev_ioctl+0x112/0x1d0 [nvme_core] [ 374.833114] do_vfs_ioctl+0xa7/0x600 [ 374.837117] ? __audit_syscall_entry+0xdd/0x130 [ 374.842184] ksys_ioctl+0x67/0x90 [ 374.845891] __x64_sys_ioctl+0x1a/0x20 [ 374.850082] do_syscall_64+0x5a/0x1c0 [ 374.854178] entry_SYSCALL_64_after_hwframe+0x44/0xa9 -- Reported-by: James Puthukattukaran Tested-by: James Puthukattukaran Reviewed-by: Keith Busch Signed-off-by: Sagi Grimberg Signed-off-by: Sasha Levin

nvme: fix multipath crash when ANA is deactivated

2019-08-04T07:29:38+00:00

commit 66b20ac0a1a10769d059d6903202f53494e3d902 upstream. Fix a crash with multipath activated. It happends when ANA log page is larger than MDTS and because of that ANA is disabled. The driver then tries to access unallocated buffer when connecting to a nvme target. The signature is as follows: [ 300.433586] nvme nvme0: ANA log page size (8208) larger than MDTS (8192). [ 300.435387] nvme nvme0: disabling ANA support. [ 300.437835] nvme nvme0: creating 4 I/O queues. [ 300.459132] nvme nvme0: new ctrl: NQN "nqn.0.0.0", addr 10.91.0.1:8009 [ 300.464609] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 300.466342] #PF error: [normal kernel read fault] [ 300.467385] PGD 0 P4D 0 [ 300.467987] Oops: 0000 [#1] SMP PTI [ 300.468787] CPU: 3 PID: 50 Comm: kworker/u8:1 Not tainted 5.0.20kalray+ #4 [ 300.470264] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 300.471532] Workqueue: nvme-wq nvme_scan_work [nvme_core] [ 300.472724] RIP: 0010:nvme_parse_ana_log+0x21/0x140 [nvme_core] [ 300.474038] Code: 45 01 d2 d8 48 98 c3 66 90 0f 1f 44 00 00 41 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 08 48 8b af 20 0a 00 00 48 89 34 24 <66> 83 7d 08 00 0f 84 c6 00 00 00 44 8b 7d 14 49 89 d5 8b 55 10 48 [ 300.477374] RSP: 0018:ffffa50e80fd7cb8 EFLAGS: 00010296 [ 300.478334] RAX: 0000000000000001 RBX: ffff9130f1872258 RCX: 0000000000000000 [ 300.479784] RDX: ffffffffc06c4c30 RSI: ffff9130edad4280 RDI: ffff9130f1872258 [ 300.481488] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044 [ 300.483203] R10: 0000000000000220 R11: 0000000000000040 R12: ffff9130f18722c0 [ 300.484928] R13: ffff9130f18722d0 R14: ffff9130edad4280 R15: ffff9130f18722c0 [ 300.486626] FS: 0000000000000000(0000) GS:ffff9130f7b80000(0000) knlGS:0000000000000000 [ 300.488538] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 300.489907] CR2: 0000000000000008 CR3: 00000002365e6000 CR4: 00000000000006e0 [ 300.491612] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 300.493303] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 300.494991] Call Trace: [ 300.495645] nvme_mpath_add_disk+0x5c/0xb0 [nvme_core] [ 300.496880] nvme_validate_ns+0x2ef/0x550 [nvme_core] [ 300.498105] ? nvme_identify_ctrl.isra.45+0x6a/0xb0 [nvme_core] [ 300.499539] nvme_scan_work+0x2b4/0x370 [nvme_core] [ 300.500717] ? __switch_to_asm+0x35/0x70 [ 300.501663] process_one_work+0x171/0x380 [ 300.502340] worker_thread+0x49/0x3f0 [ 300.503079] kthread+0xf8/0x130 [ 300.503795] ? max_active_store+0x80/0x80 [ 300.504690] ? kthread_bind+0x10/0x10 [ 300.505502] ret_from_fork+0x35/0x40 [ 300.506280] Modules linked in: nvme_tcp nvme_rdma rdma_cm iw_cm ib_cm ib_core nvme_fabrics nvme_core xt_physdev ip6table_raw ip6table_mangle ip6table_filter ip6_tables xt_comment iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_CHECKSUM iptable_mangle iptable_filter veth ebtable_filter ebtable_nat ebtables iptable_raw vxlan ip6_udp_tunnel udp_tunnel sunrpc joydev pcspkr virtio_balloon br_netfilter bridge stp llc ip_tables xfs libcrc32c ata_generic pata_acpi virtio_net virtio_console net_failover virtio_blk failover ata_piix serio_raw libata virtio_pci virtio_ring virtio [ 300.514984] CR2: 0000000000000008 [ 300.515569] ---[ end trace faa2eefad7e7f218 ]--- [ 300.516354] RIP: 0010:nvme_parse_ana_log+0x21/0x140 [nvme_core] [ 300.517330] Code: 45 01 d2 d8 48 98 c3 66 90 0f 1f 44 00 00 41 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 08 48 8b af 20 0a 00 00 48 89 34 24 <66> 83 7d 08 00 0f 84 c6 00 00 00 44 8b 7d 14 49 89 d5 8b 55 10 48 [ 300.520353] RSP: 0018:ffffa50e80fd7cb8 EFLAGS: 00010296 [ 300.521229] RAX: 0000000000000001 RBX: ffff9130f1872258 RCX: 0000000000000000 [ 300.522399] RDX: ffffffffc06c4c30 RSI: ffff9130edad4280 RDI: ffff9130f1872258 [ 300.523560] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044 [ 300.524734] R10: 0000000000000220 R11: 0000000000000040 R12: ffff9130f18722c0 [ 300.525915] R13: ffff9130f18722d0 R14: ffff9130edad4280 R15: ffff9130f18722c0 [ 300.527084] FS: 0000000000000000(0000) GS:ffff9130f7b80000(0000) knlGS:0000000000000000 [ 300.528396] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 300.529440] CR2: 0000000000000008 CR3: 00000002365e6000 CR4: 00000000000006e0 [ 300.530739] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 300.531989] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 300.533264] Kernel panic - not syncing: Fatal exception [ 300.534338] Kernel Offset: 0x17c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 300.536227] ---[ end Kernel panic - not syncing: Fatal exception ]--- Condition check refactoring from Christoph Hellwig. Signed-off-by: Marta Rybczynska Tested-by: Jean-Baptiste Riaux Signed-off-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman

nvme-multipath: avoid crash on invalid subsystem cntlid enumeration

2019-05-13T14:00:03+00:00

A process holding an open reference to a removed disk prevents it from completing deletion, so its name continues to exist. A subsequent gendisk creation may have the same cntlid which risks collision when using that for the name. Use the unique ctrl->instance instead. Signed-off-by: Hannes Reinecke Reviewed-by: Keith Busch Signed-off-by: Christoph Hellwig

nvme-multipath: don't print ANA group state by default

2019-05-01T13:17:16+00:00

Signed-off-by: Hannes Reinecke Signed-off-by: Chaitanya Kulkarni Reviewed-by: Sagi Grimberg Signed-off-by: Christoph Hellwig

nvme-multipath: split bios with the ns_head bio_set before submitting

2019-05-01T13:17:15+00:00

If the bio is moved to a different queue via blk_steal_bios() and the original queue is destroyed in nvme_remove_ns() we'll be ending with a crash in bio_endio() as the mempool for the split bio bvecs had already been destroyed. So split the bio using the original queue (which will remain during the lifetime of the bio) before sending it down to the underlying device. Signed-off-by: Hannes Reinecke Reviewed-by: Ming Lei Signed-off-by: Christoph Hellwig

nvme-multipath: relax ANA state check

2019-03-28T17:15:02+00:00

When undergoing state transitions I/O might be requeued, hence we should always call nvme_mpath_set_live() to schedule requeue_work whenever the nvme device is live, independent on whether the old state was live or not. Signed-off-by: Martin George Signed-off-by: Gargi Srinivas Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

nvme: convert to SPDX identifiers

2019-02-20T14:22:28+00:00

Update license to use SPDX-License-Identifier instead of verbose license text. Signed-off-by: Christoph Hellwig Reviewed-by: Sagi Grimberg

nvme-multipath: round-robin I/O policy

2019-02-20T14:17:49+00:00

Implement a simple round-robin I/O policy for multipathing. Path selection is done in two rounds, first iterating across all optimized paths, and if that doesn't return any valid paths, iterate over all optimized and non-optimized paths. If no paths are found, use the existing algorithm. Also add a sysfs attribute 'iopolicy' to switch between the current NUMA-aware I/O policy and the 'round-robin' I/O policy. Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig