[clang] NMI while trying to read acpi timer register

Andriy Gapon avg at FreeBSD.org
Wed Jan 30 21:03:29 UTC 2013


on 28/01/2013 16:30 Andriy Gapon said the following:
> is there any reasonable explanation for getting an NMI while trying to read acpi
> timer register?
> Note: this happens only after ACPI suspend/resume.

An update.
This happens only with clang compiled kernel, gcc compiled kernel is OK.
Also, this happens only in the depth of fwohci driver (where it calls DELAY).
If firewire is not loaded, then there is no problem.

I suspect that perhaps there is some miscompilation that results in some
incorrect I/O access that later leads to NMI.  Too many unknowns and guesses
here, obviously.

-- 
Andriy Gapon


More information about the freebsd-hackers mailing list