afs: Fix manually set volume location server list

dhowells · torvalds · commit 7d762d69145a · 2019-02-25T11:59:07.000-08:00
When a cell with a volume location server list is added manually by echoing the details into /proc/net/afs/cells, a record is added but the flag saying it has been looked up isn't set. This causes the VL server rotation code to wait forever, with the top of /proc/pid/stack looking like: afs_select_vlserver+0x3a6/0x6f3 afs_vl_lookup_vldb+0x4b/0x92 afs_create_volume+0x25/0x1b9 ... with the thread stuck in afs_start_vl_iteration() waiting for AFS_CELL_FL_NO_LOOKUP_YET to be cleared. Fix this by clearing AFS_CELL_FL_NO_LOOKUP_YET when setting up a record if that record's details were supplied manually. Fixes: 0a5143f ("afs: Implement VL server rotation") Reported-by: Dave Botsch <dwb7@cornell.edu> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/afs/cell.c b/fs/afs/cell.c
@@ -173,6 +173,7 @@ static struct afs_cell *afs_alloc_cell(struct afs_net *net,
 
 		rcu_assign_pointer(cell->vl_servers, vllist);
 		cell->dns_expiry = TIME64_MAX;
+		__clear_bit(AFS_CELL_FL_NO_LOOKUP_YET, &cell->flags);
 	} else {
 		cell->dns_expiry = ktime_get_real_seconds();
 	}

Original file line number	Diff line number	Diff line change
`@@ -173,6 +173,7 @@ static struct afs_cell afs_alloc_cell(struct afs_net net,`
`173`	`173`
`174`	`174`	`rcu_assign_pointer(cell->vl_servers, vllist);`
`175`	`175`	`cell->dns_expiry = TIME64_MAX;`
	`176`	`+ __clear_bit(AFS_CELL_FL_NO_LOOKUP_YET, &cell->flags);`
`176`	`177`	`} else {`
`177`	`178`	`cell->dns_expiry = ktime_get_real_seconds();`
`178`	`179`	`}`