mirror of
https://github.com/openwrt/openwrt.git
synced 2025-01-31 08:25:29 +00:00
generic: 6.1: add patch fixing bugs with LED netdev trigger
Backport one patch merged upstream that prevent a deadlock for LED netdev trigger and add a pending patch that fix kernel panic on interface rename trigger notification with invalid dev. Fixes: #14477 Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
This commit is contained in:
Christian Marangi
parent
79c79d9809
commit
508f2dbfb3
@ -0,0 +1,170 @@
|
|||||||
|
From fe2b1226656afae56702d1d84c6900f6b67df297 Mon Sep 17 00:00:00 2001
|
||||||
|
From: Heiner Kallweit <hkallweit1@gmail.com>
|
||||||
|
Date: Fri, 1 Dec 2023 11:23:22 +0100
|
||||||
|
Subject: [PATCH] leds: trigger: netdev: fix RTNL handling to prevent potential
|
||||||
|
deadlock
|
||||||
|
|
||||||
|
When working on LED support for r8169 I got the following lockdep
|
||||||
|
warning. Easiest way to prevent this scenario seems to be to take
|
||||||
|
the RTNL lock before the trigger_data lock in set_device_name().
|
||||||
|
|
||||||
|
======================================================
|
||||||
|
WARNING: possible circular locking dependency detected
|
||||||
|
6.7.0-rc2-next-20231124+ #2 Not tainted
|
||||||
|
------------------------------------------------------
|
||||||
|
bash/383 is trying to acquire lock:
|
||||||
|
ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
|
||||||
|
but task is already holding lock:
|
||||||
|
ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20
|
||||||
|
|
||||||
|
which lock already depends on the new lock.
|
||||||
|
|
||||||
|
the existing dependency chain (in reverse order) is:
|
||||||
|
|
||||||
|
-> #1 (rtnl_mutex){+.+.}-{3:3}:
|
||||||
|
__mutex_lock+0x9b/0xb50
|
||||||
|
mutex_lock_nested+0x16/0x20
|
||||||
|
rtnl_lock+0x12/0x20
|
||||||
|
set_device_name+0xa9/0x120 [ledtrig_netdev]
|
||||||
|
netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev]
|
||||||
|
led_trigger_set+0x172/0x2c0
|
||||||
|
led_trigger_write+0xf1/0x140
|
||||||
|
sysfs_kf_bin_write+0x5d/0x80
|
||||||
|
kernfs_fop_write_iter+0x15d/0x210
|
||||||
|
vfs_write+0x1f0/0x510
|
||||||
|
ksys_write+0x6c/0xf0
|
||||||
|
__x64_sys_write+0x14/0x20
|
||||||
|
do_syscall_64+0x3f/0xf0
|
||||||
|
entry_SYSCALL_64_after_hwframe+0x6c/0x74
|
||||||
|
|
||||||
|
-> #0 (&trigger_data->lock){+.+.}-{3:3}:
|
||||||
|
__lock_acquire+0x1459/0x25a0
|
||||||
|
lock_acquire+0xc8/0x2d0
|
||||||
|
__mutex_lock+0x9b/0xb50
|
||||||
|
mutex_lock_nested+0x16/0x20
|
||||||
|
netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
call_netdevice_register_net_notifiers+0x5a/0x100
|
||||||
|
register_netdevice_notifier+0x85/0x120
|
||||||
|
netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev]
|
||||||
|
led_trigger_set+0x172/0x2c0
|
||||||
|
led_trigger_write+0xf1/0x140
|
||||||
|
sysfs_kf_bin_write+0x5d/0x80
|
||||||
|
kernfs_fop_write_iter+0x15d/0x210
|
||||||
|
vfs_write+0x1f0/0x510
|
||||||
|
ksys_write+0x6c/0xf0
|
||||||
|
__x64_sys_write+0x14/0x20
|
||||||
|
do_syscall_64+0x3f/0xf0
|
||||||
|
entry_SYSCALL_64_after_hwframe+0x6c/0x74
|
||||||
|
|
||||||
|
other info that might help us debug this:
|
||||||
|
|
||||||
|
Possible unsafe locking scenario:
|
||||||
|
|
||||||
|
CPU0 CPU1
|
||||||
|
---- ----
|
||||||
|
lock(rtnl_mutex);
|
||||||
|
lock(&trigger_data->lock);
|
||||||
|
lock(rtnl_mutex);
|
||||||
|
lock(&trigger_data->lock);
|
||||||
|
|
||||||
|
*** DEADLOCK ***
|
||||||
|
|
||||||
|
8 locks held by bash/383:
|
||||||
|
#0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0
|
||||||
|
#1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210
|
||||||
|
#2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210
|
||||||
|
#3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140
|
||||||
|
#4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140
|
||||||
|
#5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140
|
||||||
|
#6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120
|
||||||
|
#7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20
|
||||||
|
|
||||||
|
stack backtrace:
|
||||||
|
CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2
|
||||||
|
Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023
|
||||||
|
Call Trace:
|
||||||
|
<TASK>
|
||||||
|
dump_stack_lvl+0x5c/0xd0
|
||||||
|
dump_stack+0x10/0x20
|
||||||
|
print_circular_bug+0x2dd/0x410
|
||||||
|
check_noncircular+0x131/0x150
|
||||||
|
__lock_acquire+0x1459/0x25a0
|
||||||
|
lock_acquire+0xc8/0x2d0
|
||||||
|
? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
__mutex_lock+0x9b/0xb50
|
||||||
|
? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
? __this_cpu_preempt_check+0x13/0x20
|
||||||
|
? netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
? __cancel_work_timer+0x11c/0x1b0
|
||||||
|
? __mutex_lock+0x123/0xb50
|
||||||
|
mutex_lock_nested+0x16/0x20
|
||||||
|
? mutex_lock_nested+0x16/0x20
|
||||||
|
netdev_trig_notify+0xec/0x190 [ledtrig_netdev]
|
||||||
|
call_netdevice_register_net_notifiers+0x5a/0x100
|
||||||
|
register_netdevice_notifier+0x85/0x120
|
||||||
|
netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev]
|
||||||
|
led_trigger_set+0x172/0x2c0
|
||||||
|
? preempt_count_add+0x49/0xc0
|
||||||
|
led_trigger_write+0xf1/0x140
|
||||||
|
sysfs_kf_bin_write+0x5d/0x80
|
||||||
|
kernfs_fop_write_iter+0x15d/0x210
|
||||||
|
vfs_write+0x1f0/0x510
|
||||||
|
ksys_write+0x6c/0xf0
|
||||||
|
__x64_sys_write+0x14/0x20
|
||||||
|
do_syscall_64+0x3f/0xf0
|
||||||
|
entry_SYSCALL_64_after_hwframe+0x6c/0x74
|
||||||
|
RIP: 0033:0x7f269055d034
|
||||||
|
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48
|
||||||
|
RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
|
||||||
|
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034
|
||||||
|
RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001
|
||||||
|
RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001
|
||||||
|
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007
|
||||||
|
R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000
|
||||||
|
</TASK>
|
||||||
|
|
||||||
|
Fixes: d5e01266e7f5 ("leds: trigger: netdev: add additional specific link speed mode")
|
||||||
|
Cc: stable@vger.kernel.org
|
||||||
|
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
|
||||||
|
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
|
||||||
|
Acked-by: Lee Jones <lee@kernel.org>
|
||||||
|
Link: https://lore.kernel.org/r/fb5c8294-2a10-4bf5-8f10-3d2b77d2757e@gmail.com
|
||||||
|
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
||||||
|
---
|
||||||
|
drivers/leds/trigger/ledtrig-netdev.c | 11 +++++++----
|
||||||
|
1 file changed, 7 insertions(+), 4 deletions(-)
|
||||||
|
|
||||||
|
--- a/drivers/leds/trigger/ledtrig-netdev.c
|
||||||
|
+++ b/drivers/leds/trigger/ledtrig-netdev.c
|
||||||
|
@@ -235,6 +235,11 @@ static int set_device_name(struct led_ne
|
||||||
|
{
|
||||||
|
cancel_delayed_work_sync(&trigger_data->work);
|
||||||
|
|
||||||
|
+ /*
|
||||||
|
+ * Take RTNL lock before trigger_data lock to prevent potential
|
||||||
|
+ * deadlock with netdev notifier registration.
|
||||||
|
+ */
|
||||||
|
+ rtnl_lock();
|
||||||
|
mutex_lock(&trigger_data->lock);
|
||||||
|
|
||||||
|
if (trigger_data->net_dev) {
|
||||||
|
@@ -254,16 +259,14 @@ static int set_device_name(struct led_ne
|
||||||
|
trigger_data->carrier_link_up = false;
|
||||||
|
trigger_data->link_speed = SPEED_UNKNOWN;
|
||||||
|
trigger_data->duplex = DUPLEX_UNKNOWN;
|
||||||
|
- if (trigger_data->net_dev != NULL) {
|
||||||
|
- rtnl_lock();
|
||||||
|
+ if (trigger_data->net_dev)
|
||||||
|
get_device_state(trigger_data);
|
||||||
|
- rtnl_unlock();
|
||||||
|
- }
|
||||||
|
|
||||||
|
trigger_data->last_activity = 0;
|
||||||
|
|
||||||
|
set_baseline_state(trigger_data);
|
||||||
|
mutex_unlock(&trigger_data->lock);
|
||||||
|
+ rtnl_unlock();
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
@ -0,0 +1,52 @@
|
|||||||
|
From 9e2a0a8bd7a392b5af6bf2cfa0b07d96d1fb6719 Mon Sep 17 00:00:00 2001
|
||||||
|
From: Christian Marangi <ansuelsmth@gmail.com>
|
||||||
|
Date: Sun, 4 Feb 2024 00:32:04 +0100
|
||||||
|
Subject: [PATCH] leds: trigger: netdev: Fix kernel panic on interface rename
|
||||||
|
trig notify
|
||||||
|
|
||||||
|
Commit d5e01266e7f5 ("leds: trigger: netdev: add additional specific link
|
||||||
|
speed mode") in the various changes, reworked the way to set the LINKUP
|
||||||
|
mode in commit cee4bd16c319 ("leds: trigger: netdev: Recheck
|
||||||
|
NETDEV_LED_MODE_LINKUP on dev rename") and moved it to a generic function.
|
||||||
|
|
||||||
|
This changed the logic where, in the previous implementation the dev
|
||||||
|
from the trigger event was used to check if the carrier was ok, but in
|
||||||
|
the new implementation with the generic function, the dev in
|
||||||
|
trigger_data is used instead.
|
||||||
|
|
||||||
|
This is problematic and cause a possible kernel panic due to the fact
|
||||||
|
that the dev in the trigger_data still reference the old one as the
|
||||||
|
new one (passed from the trigger event) still has to be hold and saved
|
||||||
|
in the trigger_data struct (done in the NETDEV_REGISTER case).
|
||||||
|
|
||||||
|
On calling of get_device_state(), an invalid net_dev is used and this
|
||||||
|
cause a kernel panic.
|
||||||
|
|
||||||
|
To handle this correctly, move the call to get_device_state() after the
|
||||||
|
new net_dev is correctly set in trigger_data (in the NETDEV_REGISTER
|
||||||
|
case) and correctly parse the new dev.
|
||||||
|
|
||||||
|
Fixes: d5e01266e7f5 ("leds: trigger: netdev: add additional specific link speed mode")
|
||||||
|
Cc: stable@vger.kernel.org
|
||||||
|
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
|
||||||
|
---
|
||||||
|
drivers/leds/trigger/ledtrig-netdev.c | 4 ++--
|
||||||
|
1 file changed, 2 insertions(+), 2 deletions(-)
|
||||||
|
|
||||||
|
--- a/drivers/leds/trigger/ledtrig-netdev.c
|
||||||
|
+++ b/drivers/leds/trigger/ledtrig-netdev.c
|
||||||
|
@@ -489,12 +489,12 @@ static int netdev_trig_notify(struct not
|
||||||
|
trigger_data->duplex = DUPLEX_UNKNOWN;
|
||||||
|
switch (evt) {
|
||||||
|
case NETDEV_CHANGENAME:
|
||||||
|
- get_device_state(trigger_data);
|
||||||
|
- fallthrough;
|
||||||
|
case NETDEV_REGISTER:
|
||||||
|
dev_put(trigger_data->net_dev);
|
||||||
|
dev_hold(dev);
|
||||||
|
trigger_data->net_dev = dev;
|
||||||
|
+ if (evt == NETDEV_CHANGENAME)
|
||||||
|
+ get_device_state(trigger_data);
|
||||||
|
break;
|
||||||
|
case NETDEV_UNREGISTER:
|
||||||
|
dev_put(trigger_data->net_dev);
|
||||||
Loading…
x
Reference in New Issue
Block a user