Messages in this thread | | | Date | Tue, 27 Nov 2007 09:28:25 +0000 | From | "Jan Beulich" <> | Subject | Re: Avoid creating P2P prefetch window for expansion ROMs |
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>A kernel without the patch always forced creation of a prefetch >window for expansion ROMs which was incorrect on systems where >insufficient memory resources are available for both non-prefetch >and prefetch windows. On the systems I was dealing with, the >BIOS assumes (correctly, I believe) that expansion ROM memory >resource needs will be satisfied from the non-prefetch window.
Why would ROM space generally need to be non-prefetchable? I can see that special cases might require this, but as long as ROM space really is just normal code and data, there's nothing wrong with prefetching from it I would think. Of course I realize there's no way to specify that on a per-device basis, so I think the BIOS must be relied upon here.
>I think it would still be useful to know what system/PCI adapter >combination you are seeing the problem with so that I can try >to put together a setup that will reproduce the problem here. >Alternatively, it would good if you wouldn't mind providing >more information, testing possible fixes, etc. As a start, >could you send me the following taken with and without the >patch? > - /proc/iomem > - /proc/ioports > - `dmesg` output > - `lspci -vt` output > - `lspci -vvv` output
Attached. *.0 is with the patch, *.1 is with it reverted. All output from the SLE10SP2 (2.6.16.54-based) kernel that has that patch backported.
I'd also like to note that I found that a second of the systems I'm regularly dealing with also has similar problems. I'm just not normally looking at the boot messages that closely.
Jan
[unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream][unhandled content-type:application/octet-stream] | |