[PATCH] add chan->cl check in mbox_chan_received_data()
From: Haidong Yao
Date: Tue Dec 15 2020 - 03:50:19 EST
From: Haidong Yao <haidong.yao@xxxxxxxxxx>
mailbox outbox irq is coming, but mbox_request_channel
is not be registered, so cl->rx_callback is NULL.
panic log:
[ 9.852090]c0 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
[ 9.954634]c0 pstate: 60400089 (nZCv daIf +PAN -UAO)
[ 9.954651]c0 pc : mbox_chan_received_data+0x1c/0x88
[ 9.954666]c0 lr : sprd_mbox_outbox_isr+0x1d0/0x204 [sprd_mailbox]
[ 9.967439]c0 sp : ffffffc010003e10
[ 9.967443]c0 x29: ffffffc010003e20 x28: ffffffc011c2f6c0-
[ 9.984918]c0 x27: ffffffc010e92e08 x26: 0000000000000001-
[ 10.140344]c0 x25: 0000000000000378 x24: ffffff80f4064130-
[ 10.145880]c0 x23: 0000000000000001 x22: ffffffc0091072c7-
[ 10.151418]c0 x21: ffffffc009107212 x20: 0000000000000005-
[ 10.156957]c0 x19: ffffff80f4064080 x18: ffffffc010005038-
[ 10.162494]c0 x17: 0000000000000000 x16: ffffffc010e6f844-
[ 10.168033]c0 x15: ffffffc0117abac7 x14: 000000000000003f-
[ 10.173571]c0 x13: ffff0000ffffff00 x12: ffff0a01ffffff10-
[ 10.179110]c0 x11: 0000000000000001 x10: 00000000ffffffff-
[ 10.184649]c0 x9 : ffffff80f40644a8 x8 : c366877097809900-
[ 10.190187]c0 x7 : 207273695f786f62 x6 : ffffffc011d62231-
[ 10.195726]c0 x5 : 0000000000000034 x4 : 000000000000000c-
[ 10.201265]c0 x3 : ffffffc010e9842c x2 : 0000000000000001-
[ 10.206803]c0 x1 : ffffffc010003e40 x0 : 0000000000000000-
[ 10.212343]c0 Call trace:
[ 10.215029]c0 mbox_chan_received_data+0x1c/0x88
[ 10.219705]c0 sprd_mbox_outbox_isr+0x1d0/0x204 [sprd_mailbox]
[ 10.225590]c0 __handle_irq_event_percpu+0x164/0x358
[ 10.230604]c0 handle_irq_event+0x60/0xd8
[ 10.234675]c0 handle_fasteoi_irq+0x128/0x32c
[ 10.239086]c0 __handle_domain_irq+0xa0/0x100
[ 10.243502]c0 efi_header_end+0xb8/0x15c
[ 10.247478]c0 el1_irq+0x104/0x200
[ 10.250945]c0 cpuidle_enter_state+0x158/0x2d8
[ 10.255440]c0 cpuidle_enter+0x38/0x50
[ 10.259253]c0 do_idle.llvm.10091284334483161164+0x1a4/0x294
[ 10.264963]c0 cpu_startup_entry+0x24/0x28
[ 10.269120]c0 kernel_init+0x0/0x29c
[ 10.272752]c0 start_kernel+0x0/0x418
[ 10.276468]c0 start_kernel+0x3a0/0x418
[ 10.280371]c0 Code: f90013f3 910043fd aa0003e9 f9400800 (f9401008)-
[ 10.286684]c0 ---[ end trace b868997a960c667a ]---
Signed-off-by: Haidong Yao <haidong.yao@xxxxxxxxxx>
---
drivers/mailbox/mailbox.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 3e7d4b20ab34..58697298a95f 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -152,7 +152,7 @@ static enum hrtimer_restart txdone_hrtimer(struct hrtimer *hrtimer)
void mbox_chan_received_data(struct mbox_chan *chan, void *mssg)
{
/* No buffering the received data */
- if (chan->cl->rx_callback)
+ if (chan->cl && chan->cl->rx_callback)
chan->cl->rx_callback(chan->cl, mssg);
}
EXPORT_SYMBOL_GPL(mbox_chan_received_data);
--
2.28.0