Re: [Patch v2] Make PCI extended config space (MMCONFIG) a driver opt-in

On Fri, Jan 11, 2008 at 01:12:12PM -0800, Linus Torvalds wrote:


On Fri, 11 Jan 2008, Matthew Wilcox wrote:

But they can't. We limit the size they can access to 256 bytes, unless
the kernel probed address 256 and it worked.

Umm. Probing address 256 (or *any* address) using MMCONFIG will simply
lock up the machine. HARD.

Did I miss a bug report? The only problems I'm currently aware of are
the ones where using MMCONFIG during BAR probing causes a hard lockup on
some Intel machines, and the ones where we get bad config data on some
AMD machines due to the configuration retry status being mishandled.

All the other lockups I'm aware of are already handled by the existing
checks.

--
Intel are signing my paycheques ... these opinions are still mine
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Relevant Pages

  • Re: Problem Solved
    ... this is on an AMD machine. ... > sure how this affects Intel machines, or even if certain Intel machines ...
    (microsoft.public.windowsxp.hardware)
  • Re: [PATCH] Machine Check Architecture on amd64
    ... Intel machines with bad RAM. ... reporting the corrected errors and will stop the kthread ). ...
    (freebsd-current)
  • Re: [PATCH] Machine Check Architecture on amd64
    ... Architecture/Exceptions on most recent x86 CPUs to detect memory errors: ... It will report uncorrected and corrected errors (the latter, ... Intel machines with bad RAM. ...
    (freebsd-current)
  • [PATCH] Machine Check Architecture on amd64
    ... I have a simple patch for amd64 that uses the Machine Check Architecture/Exceptions on most recent x86 CPUs to detect memory errors: ... It will report uncorrected and corrected errors ... I'm still not sure if I want this enabled by default, as I don't have any Intel machines to test this on, but I have tested it on Opteron. ...
    (freebsd-current)