From: Christoph Hellwig hch@lst.de
[ Upstream commit 5fb4aac756acacf260b9ebd88747251effa3a2f2 ]
Holding the SRCU critical section protecting the namespace list can cause deadlocks when using the per-namespace admin passthrough ioctl to delete as namespace. Release it earlier when performing per-controller ioctls to avoid that.
Reported-by: Kenneth Heitke kenneth.heitke@intel.com Reviewed-by: Chaitanya Kulkarni chaitanya.kulkarni@wdc.com Reviewed-by: Keith Busch keith.busch@intel.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/core.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 8b77e6a05f4b..23c90382a515 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -1395,14 +1395,31 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode, if (unlikely(!ns)) return -EWOULDBLOCK;
+ /* + * Handle ioctls that apply to the controller instead of the namespace + * seperately and drop the ns SRCU reference early. This avoids a + * deadlock when deleting namespaces using the passthrough interface. + */ + if (cmd == NVME_IOCTL_ADMIN_CMD || is_sed_ioctl(cmd)) { + struct nvme_ctrl *ctrl = ns->ctrl; + + nvme_get_ctrl(ns->ctrl); + nvme_put_ns_from_disk(head, srcu_idx); + + if (cmd == NVME_IOCTL_ADMIN_CMD) + ret = nvme_user_cmd(ctrl, NULL, argp); + else + ret = sed_ioctl(ctrl->opal_dev, cmd, argp); + + nvme_put_ctrl(ctrl); + return ret; + } + switch (cmd) { case NVME_IOCTL_ID: force_successful_syscall_return(); ret = ns->head->ns_id; break; - case NVME_IOCTL_ADMIN_CMD: - ret = nvme_user_cmd(ns->ctrl, NULL, argp); - break; case NVME_IOCTL_IO_CMD: ret = nvme_user_cmd(ns->ctrl, ns, argp); break; @@ -1412,8 +1429,6 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode, default: if (ns->ndev) ret = nvme_nvm_ioctl(ns, cmd, arg); - else if (is_sed_ioctl(cmd)) - ret = sed_ioctl(ns->ctrl->opal_dev, cmd, argp); else ret = -ENOTTY; }