Hi! I have got a pair of very strange panics today. I didn't saw the exact panic message for the firs one, as the X was running at the time it has halted, and all I can say about it is that it was unable to reboot and there are no coredump. For the second one I saw a message (approximate -- I type it in from paper) "panic: sbflush_locked: cc 0 || mb 0xc1bfa600 || mbcnt 0", and it looks like that as soon as it has tried to dump core it has got a second panic and went to reboot. I am unsure if the machine was able to reboot automatically, as I pressed a key to write down panic message. As in the previous case there is no core, so I can't get any backtrace from it. It all has happeden on 5.4-RELEASE-p3. -- Best regards, Alexander.