This is a note to let you know that I've just added the patch titled drm/nouveau/bar/gf100: fix access to upper half of BAR2 to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-nouveau-bar-gf100-fix-access-to-upper-half-of-bar2.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 38bcb208f60924a031b9f809f7cd252ea4a94e5f Mon Sep 17 00:00:00 2001 From: Ben Skeggs <bskeggs@xxxxxxxxxx> Date: Tue, 25 Jul 2017 11:06:47 +1000 Subject: drm/nouveau/bar/gf100: fix access to upper half of BAR2 From: Ben Skeggs <bskeggs@xxxxxxxxxx> commit 38bcb208f60924a031b9f809f7cd252ea4a94e5f upstream. Bit 30 being set causes the upper half of BAR2 to stay in physical mode, mapped over the end of VRAM, even when the rest of the BAR has been set to virtual mode. We inherited our initial value from RM, but I'm not aware of any reason we need to keep it that way. This fixes severe GPU hang/lockup issues revealed by Wayland on F26. Shout-out to NVIDIA for the quick response with the potential cause! Signed-off-by: Ben Skeggs <bskeggs@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c @@ -129,7 +129,7 @@ gf100_bar_init(struct nvkm_bar *base) if (bar->bar[0].mem) { addr = nvkm_memory_addr(bar->bar[0].mem) >> 12; - nvkm_wr32(device, 0x001714, 0xc0000000 | addr); + nvkm_wr32(device, 0x001714, 0x80000000 | addr); } return 0; Patches currently in stable-queue which might be from bskeggs@xxxxxxxxxx are queue-4.4/drm-nouveau-bar-gf100-fix-access-to-upper-half-of-bar2.patch