Re: Regression from 2.6.26: Hibernation (possibly suspend) broken on Toshiba R500 (bisected)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Wednesday, 3 of December 2008, Rafael J. Wysocki wrote:
> On Wednesday, 3 of December 2008, Linus Torvalds wrote:
> > 
> > On Wed, 3 Dec 2008, Rafael J. Wysocki wrote:
> > > 
> > > Here's the output of 'lspci -vvxxx':
> > 
> > Ok, I'm not finding any documented quirks that would be memory regions, 
> > and in fact it doesn't look like there is even any remotely likely 32-bit 
> > valies that might be pointers in your PCI config space that look remotely 
> > like they might be conflicting in the area of MMIO space that we allocate 
> > PCI resources from (ie 0x88000000-0x92000000).
> > 
> > Of course, any odd MMIO regions might be descibed by some insane model 
> > that doesn't look like an aligned 32-bit value, but that's unlikely.
> > 
> > So I'm still not seeing anything wrong in there.
> > 
> > > I'll run the 'pci=cbmemsize=4M' test tomorrow (need to have some sleep).
> > 
> > Sure. It will be interesting to see if it makes any difference.
> 
> It didn't help (failure in the 4th consecutive hibernation/resume cycle).

Moreover, to check if the problem may be related to the prefetch window,
I added the appended patch on top of -rc7 (instead of the previous debug
patch), which resulted in the following layout in /proc/iomem:

88000000-8dffffff : PCI Bus 0000:03
  88000000-8bffffff : PCI CardBus 0000:04
  8c000000-8c003fff : 0000:03:0b.1
  8c004000-8c004fff : 0000:03:0b.0
    8c004000-8c004fff : yenta_socket
  8c005000-8c0057ff : 0000:03:0b.1
    8c005000-8c0057ff : firewire_ohci
  8c005800-8c0058ff : 0000:03:0b.3
    8c005800-8c0058ff : mmc0
  8c400000-8c7fffff : PCI CardBus 0000:04

and the first hibernation-resume cycle failed.

Thanks,
Rafael

---
 drivers/pci/setup-bus.c |   19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

Index: linux-2.6/drivers/pci/setup-bus.c
===================================================================
--- linux-2.6.orig/drivers/pci/setup-bus.c
+++ linux-2.6/drivers/pci/setup-bus.c
@@ -353,6 +353,25 @@ static int pbus_size_mem(struct pci_bus 
 			r_size = resource_size(r);
 			/* For bridges size != alignment */
 			align = resource_alignment(r);
+			if (r->flags & IORESOURCE_PREFETCH) {
+				resource_size_t expected_align;
+
+				expected_align = (i < PCI_BRIDGE_RESOURCES) ?
+							r_size : r->start;
+				if (align != expected_align) {
+					dev_warn(&dev->dev,
+						"BAR %d [%llx-%llx] "
+						"alignment issue: flags=%lx "
+						"align=%llx (%llx)\n", i,
+						(unsigned long long)r->start,
+						(unsigned long long)r->end,
+						r->flags,
+						(unsigned long long)align,
+						(unsigned long long)expected_align);
+					/* Hacky and wrong, but trying to keep things */
+					align = expected_align;
+				}
+			}
 			order = __ffs(align) - 20;
 			if (order > 11) {
 				dev_warn(&dev->dev, "BAR %d bad alignment %llx: "