summary refs log tree commit diff
path: root/drivers/gpu/drm
diff options
context:
space:
mode:
authorChangbin Du <changbin.du@intel.com>2017-03-30 11:32:05 +0800
committerZhenyu Wang <zhenyuw@linux.intel.com>2017-03-30 17:47:39 +0800
commitf85726905745fb4f6e15c68e2ade9da5390f8d89 (patch)
tree458386208689f2e0eea0dfc1cf1f2cbbe71e2202 /drivers/gpu/drm
parentb79c52aef3cdee903017c1e9834b53996d70010e (diff)
downloadlinux-f85726905745fb4f6e15c68e2ade9da5390f8d89.tar.gz
drm/i915/gvt: exclude cfg space from failsafe mode
When test GVTg as below scenario:
  VM boot --> failsafe --> kill qemu --> VM boot.
Qemu report error at the second boot:
  ERROR: PCI region size must be pow2 type=0x0, size=0x1fa1000

Qemu need access PCI_ROM_ADDRESS reg to determine the size of expansion
PCI rom. The mechanism just like the BAR reg (write-read) and we should
return the size 0 since we have no rom. If we reject the write to
PCI_ROM_ADDRESS, Qemu cannot get the correct size of rom.

Essentially, GVTg failsafe mode should not break PCI function. So we
exclude cfg space from failsafe mode. This can fix above issue.

v2: add Fixes and Bugzilla link.

Fixes: fd64be636708d ("drm/i915/gvt: introduced failsafe mode into vgpu")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100296
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm')
-rw-r--r--drivers/gpu/drm/i915/gvt/cfg_space.c3
1 files changed, 0 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/gvt/cfg_space.c b/drivers/gpu/drm/i915/gvt/cfg_space.c
index b7d7721e72fa..40af17ec6312 100644
--- a/drivers/gpu/drm/i915/gvt/cfg_space.c
+++ b/drivers/gpu/drm/i915/gvt/cfg_space.c
@@ -285,9 +285,6 @@ int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
 {
 	int ret;
 
-	if (vgpu->failsafe)
-		return 0;
-
 	if (WARN_ON(bytes > 4))
 		return -EINVAL;