Kevin Winchester reported a GART related direct rendering failure against
linux-next-
20080611, which shows up via these log entries:
PCI: Using ACPI for IRQ routing
PCI: Cannot allocate resource region 0 of device 0000:00:00.0
agpgart: Detected AGP bridge 0
agpgart: Aperture conflicts with PCI mapping.
agpgart: Aperture from AGP @
e0000000 size 128 MB
agpgart: Aperture conflicts with PCI mapping.
agpgart: No usable aperture found.
agpgart: Consider rebooting with iommu=memaper=2 to get a good aperture.
instead of the expected:
PCI: Using ACPI for IRQ routing
agpgart: Detected AGP bridge 0
agpgart: Aperture from AGP @
e0000000 size 128 MB
Kevin bisected it down to this change in tip/x86/gart:
"x86: checking aperture size order".
agp check is using request_mem_region(), and could fail if e820 is reserved...
change it back to e820_any_mapped().
Reported-and-bisected-by: "Kevin Winchester" <kjwinchester@gmail.com>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Tested-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix = 1;
if (gart_fix_e820 && !fix && aper_enabled) {
- if (!e820_all_mapped(aper_base, aper_base + aper_size,
- E820_RESERVED)) {
+ if (e820_any_mapped(aper_base, aper_base + aper_size,
+ E820_RAM)) {
/* reserve it, so we can reuse it in second kernel */
printk(KERN_INFO "update e820 for GART\n");
add_memory_region(aper_base, aper_size, E820_RESERVED);