Hi, On Thu, Aug 23, 2012 at 11:02 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Thu, Aug 23, 2012 at 12:28:23AM -0700, Olof Johansson wrote: >> Hi, >> >> On Mon, Jul 9, 2012 at 11:20 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: >> > After 253d2e5498, we disable MEM and IO decoding for most devices while we >> > size 32-bit BARs. However, we restore the original COMMAND register before >> > we size the upper 32 bits of 64-bit BARs, so we can still cause a conflict. >> > >> > This patch waits to restore the original COMMAND register until we're >> > completely finished sizing the BAR. >> > >> > Reference: https://lkml.org/lkml/2007/8/25/154 >> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> >> >> This patch causes boot lockup on PA Semi hardware, since it disables >> the bar on the UART that is used for console, and it has printks >> between the old and the new re-enable location. If I boot with 'debug' >> level for printk, I hit this. If I boot with just regular console >> args, I don't. >> >> I'm guessing any other platform that uses MMIO-based UART on PCI for >> console will have similar issues. I can verify on Chrome OS x86 >> hardware tomorrow if legacy powerpc isn't important enough to care >> about. :-) >> >> I have no proposal for a fix for this. Can you please consider >> reverting for 3.6 unless someone has a better idea? > > Thanks a lot for finding and debugging this! > > Can you try the patch below? > > > commit cfc29ece86d648e63fb46de81b2bf8e3e107672c > Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Date: Thu Aug 23 10:53:08 2012 -0600 > > PCI: Don't print anything while decoding is disabled > > If we try to print to the console device while its decoding is disabled, > the system will hang. > > Reported-by: Olof Johansson <olof@xxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Ah yes, of course. Teaches me to try to do anything productive late at night. Tested fine here. Acked-by: Olof Johansson <olof@xxxxxxxxx> Thanks! -Olof -- 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
