1
linux/fs/afs
David Howells 610a79ffea
afs: Fix lock recursion
afs_wake_up_async_call() can incur lock recursion.  The problem is that it
is called from AF_RXRPC whilst holding the ->notify_lock, but it tries to
take a ref on the afs_call struct in order to pass it to a work queue - but
if the afs_call is already queued, we then have an extraneous ref that must
be put... calling afs_put_call() may call back down into AF_RXRPC through
rxrpc_kernel_shutdown_call(), however, which might try taking the
->notify_lock again.

This case isn't very common, however, so defer it to a workqueue.  The oops
looks something like:

  BUG: spinlock recursion on CPU#0, krxrpcio/7001/1646
   lock: 0xffff888141399b30, .magic: dead4ead, .owner: krxrpcio/7001/1646, .owner_cpu: 0
  CPU: 0 UID: 0 PID: 1646 Comm: krxrpcio/7001 Not tainted 6.12.0-rc2-build3+ #4351
  Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x47/0x70
   do_raw_spin_lock+0x3c/0x90
   rxrpc_kernel_shutdown_call+0x83/0xb0
   afs_put_call+0xd7/0x180
   rxrpc_notify_socket+0xa0/0x190
   rxrpc_input_split_jumbo+0x198/0x1d0
   rxrpc_input_data+0x14b/0x1e0
   ? rxrpc_input_call_packet+0xc2/0x1f0
   rxrpc_input_call_event+0xad/0x6b0
   rxrpc_input_packet_on_conn+0x1e1/0x210
   rxrpc_input_packet+0x3f2/0x4d0
   rxrpc_io_thread+0x243/0x410
   ? __pfx_rxrpc_io_thread+0x10/0x10
   kthread+0xcf/0xe0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x24/0x40
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/1394602.1729162732@warthog.procyon.org.uk
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-17 15:33:46 +02:00
..
addr_list.c
addr_prefs.c afs: Mark address lists with configured priorities 2024-01-01 16:37:27 +00:00
afs_cm.h
afs_fs.h
afs_vl.h afs: Remove unused struct and function prototype 2024-09-27 18:29:19 +02:00
afs.h afs: Parse the VolSync record in the reply of a number of RPC ops 2024-01-01 16:37:27 +00:00
callback.c afs: Overhaul invalidation handling to better support RO volumes 2024-01-01 16:37:27 +00:00
cell.c afs: Overhaul invalidation handling to better support RO volumes 2024-01-01 16:37:27 +00:00
cmservice.c
dir_edit.c afs: drop usage of folio_file_pos 2024-07-03 19:29:55 -07:00
dir_silly.c
dir.c afs: drop usage of folio_file_pos 2024-07-03 19:29:55 -07:00
dynroot.c afs: Remove afs_dynroot_d_revalidate() as it is redundant 2024-01-22 22:30:14 +00:00
file.c afs: Fix missing wire-up of afs_retry_request() 2024-09-27 18:29:19 +02:00
flock.c afs: adapt to breakup of struct file_lock 2024-02-05 13:11:42 +01:00
fs_operation.c afs: Fix the setting of the server responding flag 2024-09-27 18:29:20 +02:00
fs_probe.c afs: Fix possible infinite loop with unresponsive servers 2024-09-27 18:29:19 +02:00
fsclient.c netfs: Speed up buffered reading 2024-09-12 12:20:41 +02:00
inode.c afs: Fix post-setattr file edit to do truncation correctly 2024-08-24 16:09:16 +02:00
internal.h afs: Fix lock recursion 2024-10-17 15:33:46 +02:00
Kconfig
main.c afs: Fix ignored callbacks over ipv4 2024-02-20 09:51:21 +01:00
Makefile afs: Move the vnode/volume validity checking code into its own file 2024-01-01 16:37:27 +00:00
misc.c
mntpt.c afs: Don't cross .backup mountpoint from backup volume 2024-05-25 14:02:40 +02:00
proc.c afs: Fix missing/incorrect unlocking of RCU read lock 2024-01-22 22:30:38 +00:00
protocol_afs.h
protocol_uae.h
protocol_yfs.h
rotate.c afs: Fix possible infinite loop with unresponsive servers 2024-09-27 18:29:19 +02:00
rxrpc.c afs: Fix lock recursion 2024-10-17 15:33:46 +02:00
security.c
server_list.c afs: Fix fileserver rotation 2024-01-01 16:37:27 +00:00
server.c afs: Fix ignored callbacks over ipv4 2024-02-20 09:51:21 +01:00
super.c vfs-6.8.netfs 2024-01-19 09:10:23 -08:00
validation.c afs: Use alternative invalidation to using launder_folio 2024-05-01 18:07:34 +01:00
vl_alias.c afs: Defer volume record destruction to a workqueue 2024-01-01 16:37:27 +00:00
vl_list.c afs: Dispatch vlserver probes in priority order 2024-01-01 16:37:27 +00:00
vl_probe.c afs: Keep a record of the current fileserver endpoint state 2024-01-01 16:37:27 +00:00
vl_rotate.c
vlclient.c afs: Don't leave DONTUSE/NEWREPSITE servers out of server list 2024-01-01 16:37:27 +00:00
volume.c afs: Increase buffer size in afs_update_volume_status() 2024-02-20 09:51:21 +01:00
write.c netfs: Move max_len/max_nr_segs from netfs_io_subrequest to netfs_io_stream 2024-09-05 11:00:41 +02:00
xattr.c
xdr_fs.h
yfsclient.c netfs: Speed up buffered reading 2024-09-12 12:20:41 +02:00