| commit | 539fbd92996b1ec2a93228c56a318b53fa514df1 | |
| author | Matthew Dillon <dillon@apollo.backplane.com> | |
| Fri, 26 Jun 2015 21:05:40 +0000 (26 14:05 -0700) | ||
| committer | Matthew Dillon <dillon@apollo.backplane.com> | |
| Fri, 26 Jun 2015 21:49:30 +0000 (26 14:49 -0700) | ||
| tree | 9e77fff761e97e2510803c534b730065b6f3bc4d | treesnapshot (tar.gz zip) |
| parent | 546cb17e48cea226fbf6691c8a70373811b245e2 | commitdiff |
kernel - Fix syscons deadlock during panic
* The system console can deadlock during a panic if a cpu is stopped
while holding syscons_mtx.
* The new asynchronous update thread makes this problem more likely to occur.
* Fix the problem by recoding syscons_lock() to detect the panic or shutdown
condition and loop for up to 0.5 seconds trying to get the syscons_mtx.
If it is unable to acquire it, it reinitializes the mutex.
* We still have issues with VT switching away from X.
* The system console can deadlock during a panic if a cpu is stopped
while holding syscons_mtx.
* The new asynchronous update thread makes this problem more likely to occur.
* Fix the problem by recoding syscons_lock() to detect the panic or shutdown
condition and loop for up to 0.5 seconds trying to get the syscons_mtx.
If it is unable to acquire it, it reinitializes the mutex.
* We still have issues with VT switching away from X.