[PATCH 6.1 0917/1146] devlink: hold region lock when flushing snapshots

From: Jakub Kicinski kuba@kernel.org

[ Upstream commit b4cafb3d2c740f8d1b1234b43ac4a60e5291c960 ]

Netdevsim triggers a splat on reload, when it destroys regions with snapshots pending:

WARNING: CPU: 1 PID: 787 at net/core/devlink.c:6291 devlink_region_snapshot_del+0x12e/0x140 CPU: 1 PID: 787 Comm: devlink Not tainted 6.1.0-07460-g7ae9888d6e1c #580 RIP: 0010:devlink_region_snapshot_del+0x12e/0x140 Call Trace: <TASK> devl_region_destroy+0x70/0x140 nsim_dev_reload_down+0x2f/0x60 [netdevsim] devlink_reload+0x1f7/0x360 devlink_nl_cmd_reload+0x6ce/0x860 genl_family_rcv_msg_doit.isra.0+0x145/0x1c0

This is the locking assert in devlink_region_snapshot_del(), we're supposed to be holding the region->snapshot_lock here.

Fixes: 2dec18ad826f ("net: devlink: remove region snapshots list dependency on devlink->lock") Signed-off-by: Jakub Kicinski kuba@kernel.org Reviewed-by: Jiri Pirko jiri@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/devlink.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/net/core/devlink.c b/net/core/devlink.c index 89baa7c0938b..e8f1af4231db 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -11435,8 +11435,10 @@ void devl_region_destroy(struct devlink_region *region) devl_assert_locked(devlink);

/* Free all snapshots of region */ + mutex_lock(&region->snapshot_lock); list_for_each_entry_safe(snapshot, ts, &region->snapshot_list, list) devlink_region_snapshot_del(region, snapshot); + mutex_unlock(&region->snapshot_lock);

list_del(&region->list); mutex_destroy(&region->snapshot_lock);