[PATCH v1] Bluetooth: btmtk: Fix kernel crash when entering btmtk_usb_suspend

[Nícolas F. R. A. Prado]

On Tue, Jul 16, 2024 at 03:49:47PM +0800, Chris Lu wrote:
> If MediaTek's Bluetooth setup is unsuccessful, a NULL pointer issue
> occur when the system is suspended and the anchored kill function
> is called. To avoid this, add protection to prevent executing the
> anchored kill function if the setup is unsuccessful.
> 
> [    6.922106] Hardware name: Acer Tomato (rev2) board (DT)
> [    6.922114] Workqueue: pm pm_runtime_work
> [    6.922132] pstate: 804000c9
> (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [    6.922147] pc : usb_kill_anchored_urbs+0x6c/0x1e0
> [    6.922164] lr : usb_kill_anchored_urbs+0x48/0x1e0
> [    6.922181] sp : ffff800080903b60
> [    6.922187] x29: ffff800080903b60
> x28: ffff2c7b85c32b80 x27: ffff2c7bbb370930
> [    6.922211] x26: 00000000000f4240
> x25: 00000000ffffffff x24: ffffd49ece2dcb48
> [    6.922255] x20: ffffffffffffffd8
> x19: 0000000000000000 x18: 0000000000000006
> [    6.922276] x17: 6531656337386238
> x16: 3632373862333863 x15: ffff800080903480
> [    6.922297] x14: 0000000000000000
> x13: 303278302f303178 x12: ffffd49ecf090e30
> [    6.922318] x11: 0000000000000001
> x10: 0000000000000001 x9 : ffffd49ecd2c5bb4
> [    6.922339] x8 : c0000000ffffdfff
> x7 : ffffd49ecefe0db8 x6 : 00000000000affa8
> [    6.922360] x5 : ffff2c7bbb35dd48
> x4 : 0000000000000000 x3 : 0000000000000000
> [    6.922379] x2 : 0000000000000000
> x1 : 0000000000000003 x0 : ffffffffffffffd8
> [    6.922400] Call trace:
> [    6.922405]  usb_kill_anchored_urbs+0x6c/0x1e0
> [    6.922422]  btmtk_usb_suspend+0x20/0x38
> [btmtk 5f200a97badbdfda4266773fee49acfc8e0224d5]
> [    6.922444]  btusb_suspend+0xd0/0x210
> [btusb 0bfbf19a87ff406c83b87268b87ce1e80e9a829b]
> [    6.922469]  usb_suspend_both+0x90/0x288
> [    6.922487]  usb_runtime_suspend+0x3c/0xa8
> [    6.922507]  __rpm_callback+0x50/0x1f0
> [    6.922523]  rpm_callback+0x70/0x88
> [    6.922538]  rpm_suspend+0xe4/0x5a0
> [    6.922553]  pm_runtime_work+0xd4/0xe0
> [    6.922569]  process_one_work+0x18c/0x440
> [    6.922588]  worker_thread+0x314/0x428
> [    6.922606]  kthread+0x128/0x138
> [    6.922621]  ret_from_fork+0x10/0x20
> [    6.922644] Code: f100a274 54000520 d503201f d100a260 (b8370000)
> [    6.922654] ---[ end trace 0000000000000000 ]---
> 
> Fixes: ceac1cb0259d ("Bluetooth: btusb: mediatek: add ISO data transmission functions")
> Signed-off-by: Chris Lu <chris.lu at mediatek.com>

Hi Chris,

thank you for the patch. Please add the following tags:

Reported-by: Nícolas F. R. A. Prado <nfraprado at collabora.com> #KernelCI
Closes: https://lore.kernel.org/all/7851401b-e884-4ed4-998d-7651f427ad37@notapiano

Those will make it easier to find the bug report and also make sure regzbot
closes the issue once the patch is merged.

I've tested this patch and indeed it fixes the issue, so please also add

Tested-by: Nícolas F. R. A. Prado <nfraprado at collabora.com>

Thanks,
Nícolas