mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-03-22 07:27:12 +08:00
syzbot reports "task hung in rpm_resume"
This is caused by aqc111_suspend calling
the PM variant of its write_cmd routine.
The simplified call trace looks like this:
rpm_suspend()
usb_suspend_both() - here udev->dev.power.runtime_status == RPM_SUSPENDING
aqc111_suspend() - called for the usb device interface
aqc111_write32_cmd()
usb_autopm_get_interface()
pm_runtime_resume_and_get()
rpm_resume() - here we call rpm_resume() on our parent
rpm_resume() - Here we wait for a status change that will never happen.
At this point we block another task which holds
rtnl_lock and locks up the whole networking stack.
Fix this by replacing the write_cmd calls with their _nopm variants
Reported-by: syzbot+48dc1e8dfc92faf1124c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=48dc1e8dfc92faf1124c
Fixes: e58ba4544c ("net: usb: aqc111: Add support for wake on LAN by MAGIC packet")
Signed-off-by: Nikola Z. Ivanov <zlatistiv@gmail.com>
Link: https://patch.msgid.link/20260313141643.1181386-1-zlatistiv@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>