On Wed, Jan 18, 2012 at 8:49 AM, Martin Burnicki <martin.burnicki@xxxxxxxxxxx> wrote: > Hi folks, > > I'm maintaining the driver software for the PCI cards manufactured by our > company, Meinberg Funkuhren in Germany. Basically our Linux driver supports > all our PCI cards on all Linux kernels 2.6.x and 3.x. The PCI cards are e.g. > GPS receivers, radio clocks, or IRIG time code receivers. > > Recently I've run into a problem with our PCI Express cards in a certain > server PC: There are 8 PCI Express slots on the mainboard, and in some of > the slots the cards work properly, but in some other slots on the same > machine they don't work since the cards are not accessible by the kernel > driver. > > In cases where the cards are not accessible lspci -v reports > for the I/O base address 0: > > Region 0: I/O ports at <ignored> >From the lspci source (http://mj.ucw.cz/sw/pciutils/), it looks like this happens when the BAR contains zero. > Finally I tried different Linux distributions with different kernel versions > and found that the same card in the same slot with the same driver works > properly under kernel 2.6.32 and earlier, but doesn't work anymore under > kernel 2.6.36 and later, including kernel 3.1.4. So there must have been > some code changes in the newer kernel versions which prevent the card from > being accessed via I/O, and let lspci say "I/O ports at <ignored>". Please open a bug report at http://bugzilla.kernel.org, category Drivers/PCI, mark it as a regression, add me to the CC: list, and attach complete dmesg logs from 2.6.32 and 3.1.4 with the card in the slot that no longer works. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
