4.17-stable review patch. If anyone has any objections, please let me know.
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From: Scott Bauer scott.bauer@intel.com
[ Upstream commit cf39a6bc342b980f10f344d88035829638a89a48 ]
If the controller supports effects and goes down during the passthru admin command we will deadlock during namespace revalidation.
[ 363.488275] INFO: task kworker/u16:5:231 blocked for more than 120 seconds. [ 363.488290] Not tainted 4.17.0+ #2 [ 363.488296] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 363.488303] kworker/u16:5 D 0 231 2 0x80000000 [ 363.488331] Workqueue: nvme-reset-wq nvme_reset_work [nvme] [ 363.488338] Call Trace: [ 363.488385] schedule+0x75/0x190 [ 363.488396] rwsem_down_read_failed+0x1c3/0x2f0 [ 363.488481] call_rwsem_down_read_failed+0x14/0x30 [ 363.488504] down_read+0x1d/0x80 [ 363.488523] nvme_stop_queues+0x1e/0xa0 [nvme_core] [ 363.488536] nvme_dev_disable+0xae4/0x1620 [nvme] [ 363.488614] nvme_reset_work+0xd1e/0x49d9 [nvme] [ 363.488911] process_one_work+0x81a/0x1400 [ 363.488934] worker_thread+0x87/0xe80 [ 363.488955] kthread+0x2db/0x390 [ 363.488977] ret_from_fork+0x35/0x40
Fixes: 84fef62d135b6 ("nvme: check admin passthru command effects") Signed-off-by: Scott Bauer scott.bauer@intel.com Reviewed-by: Keith Busch keith.busch@linux.intel.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/nvme/host/core.c | 50 ++++++++++++++++++++++++----------------------- 1 file changed, 26 insertions(+), 24 deletions(-)
--- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -100,6 +100,22 @@ static struct class *nvme_subsys_class; static void nvme_ns_remove(struct nvme_ns *ns); static int nvme_revalidate_disk(struct gendisk *disk); static void nvme_put_subsystem(struct nvme_subsystem *subsys); +static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl, + unsigned nsid); + +static void nvme_set_queue_dying(struct nvme_ns *ns) +{ + /* + * Revalidating a dead namespace sets capacity to 0. This will end + * buffered writers dirtying pages that can't be synced. + */ + if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags)) + return; + revalidate_disk(ns->disk); + blk_set_queue_dying(ns->queue); + /* Forcibly unquiesce queues to avoid blocking dispatch */ + blk_mq_unquiesce_queue(ns->queue); +}
int nvme_reset_ctrl(struct nvme_ctrl *ctrl) { @@ -1130,19 +1146,15 @@ static u32 nvme_passthru_start(struct nv
static void nvme_update_formats(struct nvme_ctrl *ctrl) { - struct nvme_ns *ns, *next; - LIST_HEAD(rm_list); + struct nvme_ns *ns;
- down_write(&ctrl->namespaces_rwsem); - list_for_each_entry(ns, &ctrl->namespaces, list) { - if (ns->disk && nvme_revalidate_disk(ns->disk)) { - list_move_tail(&ns->list, &rm_list); - } - } - up_write(&ctrl->namespaces_rwsem); + down_read(&ctrl->namespaces_rwsem); + list_for_each_entry(ns, &ctrl->namespaces, list) + if (ns->disk && nvme_revalidate_disk(ns->disk)) + nvme_set_queue_dying(ns); + up_read(&ctrl->namespaces_rwsem);
- list_for_each_entry_safe(ns, next, &rm_list, list) - nvme_ns_remove(ns); + nvme_remove_invalid_namespaces(ctrl, NVME_NSID_ALL); }
static void nvme_passthru_end(struct nvme_ctrl *ctrl, u32 effects) @@ -3110,7 +3122,7 @@ static void nvme_remove_invalid_namespac
down_write(&ctrl->namespaces_rwsem); list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) { - if (ns->head->ns_id > nsid) + if (ns->head->ns_id > nsid || test_bit(NVME_NS_DEAD, &ns->flags)) list_move_tail(&ns->list, &rm_list); } up_write(&ctrl->namespaces_rwsem); @@ -3488,19 +3500,9 @@ void nvme_kill_queues(struct nvme_ctrl * if (ctrl->admin_q) blk_mq_unquiesce_queue(ctrl->admin_q);
- list_for_each_entry(ns, &ctrl->namespaces, list) { - /* - * Revalidating a dead namespace sets capacity to 0. This will - * end buffered writers dirtying pages that can't be synced. - */ - if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags)) - continue; - revalidate_disk(ns->disk); - blk_set_queue_dying(ns->queue); + list_for_each_entry(ns, &ctrl->namespaces, list) + nvme_set_queue_dying(ns);
- /* Forcibly unquiesce queues to avoid blocking dispatch */ - blk_mq_unquiesce_queue(ns->queue); - } up_read(&ctrl->namespaces_rwsem); } EXPORT_SYMBOL_GPL(nvme_kill_queues);