APM: fix deadlock in APM_IOC_SUSPEND ioctl
I found the Xorg server on my ARM device stuck in the 'msleep()' loop in apm_ioctl. I suspect it had attempted suspend immediately after resuming and lost a race. During that msleep(10);, a new suspend cycle must have started and changed ->suspend_state to SUSPEND_PENDING, so it was never seen to be SUSPEND_DONE and the loop could never exited. It would have moved on to SUSPEND_ACKTO but never been able to reach SUSPEND_DONE. So change the loop to only run while SUSPEND_ACKED rather than until SUSPEND_DONE. This is much safer. Signed-off-by:NeilBrown <neilb@suse.de> Signed-off-by:
Jiri Kosina <jkosina@suse.cz>
parent
b4a133da
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