ixgbe: Add locking to prevent panic when setting sriov_numvfs to zero
It is possible to disable VFs while the PF driver is processing requests
from the VF driver. This can result in a panic.
BUG: unable to handle kernel paging request at
000000000000106c
PGD 0 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 8 PID: 0 Comm: swapper/8 Kdump: loaded Tainted: G I --------- -
Hardware name: Dell Inc. PowerEdge R740/06WXJT, BIOS 2.8.2 08/27/2020
RIP: 0010:ixgbe_msg_task+0x4c8/0x1690 [ixgbe]
Code: 00 00 48 8d 04 40 48 c1 e0 05 89 7c 24 24 89 fd 48 89 44 24 10 83 ff
01 0f 84 b8 04 00 00 4c 8b 64 24 10 4d 03 a5 48 22 00 00 <41> 80 7c 24 4c
00 0f 84 8a 03 00 00 0f b7 c7 83 f8 08 0f 84 8f 0a
RSP: 0018:
ffffb337869f8df8 EFLAGS:
00010002
RAX:
0000000000001020 RBX:
0000000000000000 RCX:
000000000000002b
RDX:
0000000000000002 RSI:
0000000000000008 RDI:
0000000000000006
RBP:
0000000000000006 R08:
0000000000000002 R09:
0000000000029780
R10:
00006957d8f42832 R11:
0000000000000000 R12:
0000000000001020
R13:
ffff8a00e8978ac0 R14:
000000000000002b R15:
ffff8a00e8979c80
FS:
0000000000000000(0000) GS:
ffff8a07dfd00000(0000) knlGS:
00000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
000000000000106c CR3:
0000000063e10004 CR4:
00000000007726e0
DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
PKRU:
55555554
Call Trace:
<IRQ>
? ttwu_do_wakeup+0x19/0x140
? try_to_wake_up+0x1cd/0x550
? ixgbevf_update_xcast_mode+0x71/0xc0 [ixgbevf]
ixgbe_msix_other+0x17e/0x310 [ixgbe]
__handle_irq_event_percpu+0x40/0x180
handle_irq_event_percpu+0x30/0x80
handle_irq_event+0x36/0x53
handle_edge_irq+0x82/0x190
handle_irq+0x1c/0x30
do_IRQ+0x49/0xd0
common_interrupt+0xf/0xf
This can be eventually be reproduced with the following script:
while :
do
echo 63 > /sys/class/net/<devname>/device/sriov_numvfs
sleep 1
echo 0 > /sys/class/net/<devname>/device/sriov_numvfs
sleep 1
done
Add lock when disabling SR-IOV to prevent process VF mailbox communication.
Fixes:
d773d1310625 ("ixgbe: Fix memory leak when SR-IOV VFs are direct assigned")
Signed-off-by: Piotr Skajewski <piotrx.skajewski@intel.com>
Tested-by: Marek Szlosek <marek.szlosek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20220715214456.2968711-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>