Commit 37953cec authored by Maurizio Lombardi's avatar Maurizio Lombardi Committed by Keith Busch
Browse files

nvme: fix race condition between connected uevent and STARTED_ONCE flag 



When a controller connects, nvme_start_ctrl() emits the
"NVME_EVENT=connected" uevent and sets the NVME_CTRL_STARTED_ONCE flag.
Currently, the uevent is emitted before the flag is set. This creates a
race condition for userspace tools (like udev rules) that might rely on
the "connected" event to configure other attributes.

Swap the order of operations in nvme_start_ctrl() so that the
NVME_CTRL_STARTED_ONCE flag is set before the uevent is sent. This
guarantees that the admin_timeout can already be changed when userspace
is notified.

Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Reviewed-by: default avatarHannes Reinecke <hare@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDaniel Wagner <dwagner@suse.de>
Signed-off-by: default avatarMaurizio Lombardi <mlombard@redhat.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent 40df2172

drivers/nvme/host/core.c

+1 −1
Original line number Diff line number Diff line
@@ -5045,8 +5045,8 @@ void nvme_start_ctrl(struct nvme_ctrl *ctrl) 
		nvme_mpath_update(ctrl);

	}



	nvme_change_uevent(ctrl, "NVME_EVENT=connected");

	set_bit(NVME_CTRL_STARTED_ONCE, &ctrl->flags);

	nvme_change_uevent(ctrl, "NVME_EVENT=connected");

}

EXPORT_SYMBOL_GPL(nvme_start_ctrl);