linux/include
Johannes Berg d136f1bd36 genetlink: fix netns vs. netlink table locking
Since my commits introducing netns awareness into
genetlink we can get this problem:

BUG: scheduling while atomic: modprobe/1178/0x00000002
2 locks held by modprobe/1178:
 #0:  (genl_mutex){+.+.+.}, at: [<ffffffff8135ee1a>] genl_register_mc_grou
 #1:  (rcu_read_lock){.+.+..}, at: [<ffffffff8135eeb5>] genl_register_mc_g
Pid: 1178, comm: modprobe Not tainted 2.6.31-rc8-wl-34789-g95cb731-dirty #
Call Trace:
 [<ffffffff8103e285>] __schedule_bug+0x85/0x90
 [<ffffffff81403138>] schedule+0x108/0x588
 [<ffffffff8135b131>] netlink_table_grab+0xa1/0xf0
 [<ffffffff8135c3a7>] netlink_change_ngroups+0x47/0x100
 [<ffffffff8135ef0f>] genl_register_mc_group+0x12f/0x290

because I overlooked that netlink_table_grab() will
schedule, thinking it was just the rwlock. However,
in the contention case, that isn't actually true.

Fix this by letting the code grab the netlink table
lock first and then the RCU for netns protection.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-14 17:02:50 -07:00
..
acpi
asm-generic Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-09-14 10:37:28 -07:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2009-09-11 09:38:37 -07:00
drm
keys
linux genetlink: fix netns vs. netlink table locking 2009-09-14 17:02:50 -07:00
math-emu
media
mtd
net Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6 2009-09-10 18:17:09 -07:00
pcmcia
rdma
rxrpc
scsi
sound Merge branch 'topic/ymfpci' into for-linus 2009-09-10 15:33:09 +02:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-09-14 10:37:28 -07:00
video
xen
Kbuild