Comment 101 for bug 339091

Well, git bisect shows that revert

commit: 79f11c19a396e8cea7dad322dcfb46c0a8517fe6
drm/i915: save/restore fence registers across suspend/resume

make kernel 2.6.30 resume works again. kernel 2.6.30-rc5 + the above commit doesn't cause this hang, so it could be some conflict between this commit and other commits for kernel 2.6.30-rc6.

Here is some addition info.

i915_gem_fence_regs before suspend:

Reserved fences = 3
Total fences = 16
Fenced object[ 0] = unused
Fenced object[ 1] = unused
Fenced object[ 2] = unused
Fenced object[ 3] = f676c360: P 00c00000 00400000 00001000 X 00000002 00000002 0 (name: 1)
Fenced object[ 4] = f6901f00: 02000000 00400000 00001000 X 00000002 00000002 0 (name: 2)
Fenced object[ 5] = f6901f60: 02400000 00400000 00001000 X 00000002 00000002 0 (name: 3)
Fenced object[ 6] = unused
Fenced object[ 7] = unused
Fenced object[ 8] = unused
Fenced object[ 9] = unused
Fenced object[10] = unused
Fenced object[11] = unused
Fenced object[12] = unused
Fenced object[13] = unused
Fenced object[14] = unused
Fenced object[15] = unused

i915_gem_fence_regs after resume:

Reserved fences = 3
Total fences = 16
Fenced object[ 0] = unused
Fenced object[ 1] = unused
Fenced object[ 2] = unused
Fenced object[ 3] = f6042780: P 00c00000 00400000 00001000 X 00000002 00000000 0 (name: 1)
Fenced object[ 4] = unused
Fenced object[ 5] = unused
Fenced object[ 6] = unused
Fenced object[ 7] = unused
Fenced object[ 8] = unused
Fenced object[ 9] = unused
Fenced object[10] = unused
Fenced object[11] = unused
Fenced object[12] = unused
Fenced object[13] = unused
Fenced object[14] = unused
Fenced object[15] = unused