Fix a lock up where we enter swapper() with interrupts disabled.

In smp_rendezvous_cpus we expect to wait for all cpus to enter
smp_rendezvous_action. If we call this holding a proc lock swapper may
attempt to also lock it, however as interrupts are disabled the cpu never
handles the ipi. Because smp_rendezvous_action waits for all signaled
cpus before contining it may get caught waiting for the cpu running swapper
as the proc mutex will be unlocked after smp_rendezvous_cpus finishes.

The fix is to enable interrupts in the configure stage as we should be
doing.

MFC after:	1 week

This commit is contained in:

Andrew Turner

2015-05-23 23:08:16 +00:00

parent f22cb06aeb

commit e81032ad24

1 changed files with 1 additions and 0 deletions

									
										sys/arm/arm/autoconf.c
									
		+1
		
												View File
												
				@@ -94,6 +94,7 @@ static void

				configure_final(void *dummy)

				{

					enable_interrupts(PSR_I | PSR_F);

					cninit_finish();

					cold = 0;

				}