>Number:         178061
>Category:       kern
>Synopsis:       [ukbd] panic at reboot when hitting scroll-lock; race 
>condition with interrupt handler in lower half of kernel
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Apr 22 20:10:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Garrett Cooper
>Release:        10-CURRENT
>Organization:
EMC Isilon
>Environment:
FreeBSD 10.0-CURRENT #0: Sat Apr 13 22:16:27 UTC 2013
>Description:
I was installing FreeBSD 10-CURRENT [1] on a machine with IPMI and happened to 
hit the scroll lock when the syncer was running at reboot over IPMI and it 
generated an interrupt which caused the ukbd(4) driver to panic. Unfortunately 
I didn't capture any additional details, but it should be relatively easy to 
reproduce.

1. 
ftp://ftp.freebsd.org/pub/FreeBSD/snapshots/amd64/amd64/ISO-IMAGES/10.0/FreeBSD-10.0-CURRENT-amd64-20130413-r249439-release.iso
>How-To-Repeat:
Hit scroll lock at reboot. This may require several tries in order to hit the 
magic race condition
>Fix:
The solution would be for ukbd to properly mask interrupts when it shouldn't be 
servicing them at reboot/shutdown. This is tricky though because the kernel 
could panic at reboot and hence the driver should be functional for service via 
ddb in "recoverable"/"debuggable" scenarios, BUT it should be easy to call a 
resume hook for the driver or unmask the interrupts again in ukbd.

>Release-Note:
>Audit-Trail:
>Unformatted:
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-bugs
To unsubscribe, send any mail to "[email protected]"

Reply via email to