From: Kevin Brace <kevinbrace@xxxxxxxxxxxxxxxxxxxx> Hi, I work on an out of the kernel tree DRM module for VIA Technologies Chrome integrated graphics (https://cgit.freedesktop.org/openchrome/drm-openchrome/), and DRM commit e3c92eb4a84fb0f00442e6b5cabf4f11b0eaaf41 (drm/ttm: rework on ttm_resource to use size_t type) definitely breaks my code. The bug is 100% reproducible. It took me about 2 1/2 weeks to track down the bad commit due to the general difficulty of debugging DRM code since it gets loaded by the OS way before sysklogd service is even up and running to record a crash. For this bug, bug check did not come on, so this made it very hard to track down the bad commit. After reversing many commits, I was able to see a difference in the behavior of the code if this particular commit was reversed. I am including a patch that I think correctly fixes the erroneous code, and OpenChrome DRM works correctly (i.e., OS now boots properly) if the patch is applied. Please be more careful tinkering with TTM in the future since it tends to be very fragile. -- Kevin Brace (1): drm/ttm: Fix of rework on ttm_resource to use size_t type commit drivers/gpu/drm/ttm/ttm_bo_util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.38.2
