[PATCH 6.6 149/160] net: macb: Move devm_{free,request}_irq() out of spin lock area

Greg Kroah-Hartman
2026-04-08T18:26:43Z

From: Kevin Hao <haokexin@gmail.com>

[ Upstream commit 317e49358ebbf6390fa439ef3c142f9239dd25fb ]

The devm_free_irq() and devm_request_irq() functions should not be
executed in an atomic context.

During device suspend, all userspace processes and most kernel threads
are frozen. Additionally, we flush all tx/rx status, disable all macb
interrupts, and halt rx operations. Therefore, it is safe to split the
region protected by bp->lock into two independent sections, allowing
devm_free_irq() and devm_request_irq() to run in a non-atomic context.
This modification resolves the following lockdep warning:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:591
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 501, name: rtcwake
preempt_count: 1, expected: 0
RCU nest depth: 1, expected: 0
7 locks held by rtcwake/501:
#0: ffff0008038c3408 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0xf8/0x368
#1: ffff0008049a5e88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0xbc/0x1c8
#2: ffff00080098d588 (kn->active#70){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xcc/0x1c8
#3: ffff800081c84888 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0x1ec/0x290
#4: ffff0008009ba0f8 (&dev->mutex){....}-{4:4}, at: device_suspend+0x118/0x4f0
#5: ffff800081d00458 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48
#6: ffff0008031fb9e0 (&bp->lock){-.-.}-{3:3}, at: macb_suspend+0x144/0x558
irq event stamp: 8682
hardirqs last enabled at (8681): [<ffff8000813c7d7c>] _raw_spin_unlock_irqrestore+0x44/0x88
hardirqs last disabled at (8682): [<ffff8000813c7b58>] _raw_spin_lock_irqsave+0x38/0x98
softirqs last enabled at (7322): [<ffff8000800f1b4c>] handle_softirqs+0x52c/0x588
softirqs last disabled at (7317): [<ffff800080010310>] __do_softirq+0x20/0x2c
CPU: 1 UID: 0 PID: 501 Comm: rtcwake Not tainted 7.0.0-rc3-next-20260310-yocto-standard+ #125 PREEMPT
Hardware name: ZynqMP ZCU102 Rev1.1 (DT)
Call trace:
show_stack+0x24/0x38 (C)
__dump_stack+0x28/0x38
dump_stack_lvl+0x64/0x88
dump_stack+0x18/0x24
__might_resched+0x200/0x218
__might_sleep+0x38/0x98
__mutex_lock_common+0x7c/0x1378
mutex_lock_nested+0x38/0x50
free_irq+0x68/0x2b0
devm_irq_release+0x24/0x38
devres_release+0x40/0x80
devm_free_irq+0x48/0x88
macb_suspend+0x298/0x558
device_suspend+0x218/0x4f0
dpm_suspend+0x244/0x3a0
dpm_suspend_start+0x50/0x78
suspend_devices_and_enter+0xec/0x560
pm_suspend+0x194/0x290
state_store+0x110/0x158
kobj_attr_store+0x1c/0x30
sysfs_kf_write+0xa8/0xd0
kernfs_fop_write_iter+0x11c/0x1c8
vfs_write+0x248/0x368
ksys_write+0x7c/0xf8
__arm64_sys_write+0x28/0x40
invoke_syscall+0x4c/0xe8
el0_svc_common+0x98/0xf0
do_el0_svc+0x28/0x40
el0_svc+0x54/0x1e0
el0t_64_sync_handler+0x84/0x130
el0t_64_sync+0x198/0x1a0

Fixes: 558e35ccfe95 ("net: macb: WoL support for GEM type of Ethernet controller")
Cc: stable@vger.kernel.org
Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Link: https://patch.msgid.link/20260318-macb-irq-v2-1-f1179768ab24@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ replaced `tmp` variable with direct `MACB_BIT(MAG)` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/cadence/macb_main.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5384,6 +5384,8 @@ static int __maybe_unused macb_suspend(s
macb_writel(bp, TSR, -1);
macb_writel(bp, RSR, -1);

+ spin_unlock_irqrestore(&bp->lock, flags);
+
/* Change interrupt handler and
* Enable WoL IRQ on queue 0
*/
@@ -5395,11 +5397,12 @@ static int __maybe_unused macb_suspend(s
dev_err(dev,
"Unable to request IRQ %d (error %d)\n",
bp->queues[0].irq, err);
- spin_unlock_irqrestore(&bp->lock, flags);
return err;
}
+ spin_lock_irqsave(&bp->lock, flags);
queue_writel(bp->queues, IER, GEM_BIT(WOL));
gem_writel(bp, WOL, MACB_BIT(MAG));
+ spin_unlock_irqrestore(&bp->lock, flags);
} else {
err = devm_request_irq(dev, bp->queues[0].irq, macb_wol_interrupt,
IRQF_SHARED, netdev->name, bp->queues);
@@ -5407,13 +5410,13 @@ static int __maybe_unused macb_suspend(s
dev_err(dev,
"Unable to request IRQ %d (error %d)\n",
bp->queues[0].irq, err);
- spin_unlock_irqrestore(&bp->lock, flags);
return err;
}
+ spin_lock_irqsave(&bp->lock, flags);
queue_writel(bp->queues, IER, MACB_BIT(WOL));
macb_writel(bp, WOL, MACB_BIT(MAG));
+ spin_unlock_irqrestore(&bp->lock, flags);
}
- spin_unlock_irqrestore(&bp->lock, flags);

enable_irq_wake(bp->queues[0].irq);
}
@@ -5480,6 +5483,8 @@ static int __maybe_unused macb_resume(st
queue_readl(bp->queues, ISR);
if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
queue_writel(bp->queues, ISR, -1);
+ spin_unlock_irqrestore(&bp->lock, flags);
+
/* Replace interrupt handler on queue 0 */
devm_free_irq(dev, bp->queues[0].irq, bp->queues);
err = devm_request_irq(dev, bp->queues[0].irq, macb_interrupt,
@@ -5488,10 +5493,8 @@ static int __maybe_unused macb_resume(st
dev_err(dev,
"Unable to request IRQ %d (error %d)\n",
bp->queues[0].irq, err);
- spin_unlock_irqrestore(&bp->lock, flags);
return err;
}
- spin_unlock_irqrestore(&bp->lock, flags);

disable_irq_wake(bp->queues[0].irq);