Patch "drm/nouveau/mmu: ALIGN_DOWN correct variable" has been added to the 4.15-stable tree
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This is a note to let you know that I've just added the patch titled
drm/nouveau/mmu: ALIGN_DOWN correct variable
to the 4.15-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-mmu-align_down-correct-variable.patch
and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From
da5e45e619b3f101420c38b3006a9ae4f3ad19b0Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C4=81ris=20Narti=C5=A1s?= <[email protected]>
Date: Fri, 16 Mar 2018 11:38:43 +1000
Subject: drm/nouveau/mmu: ALIGN_DOWN correct variable
From: Māris Nartišs <[email protected]>
commit da5e45e619b3f101420c38b3006a9ae4f3ad19b0 upstream.
Commit 7110c89bb8852ff8b0f88ce05b332b3fe22bd11e ("mmu: swap out round for ALIGN") replaced two calls to round/rounddown with ALIGN/ALIGN_DOWN, but erroneously applied ALIGN_DOWN to a different variable (addr) and left intended variable (tail) not rounded/ALIGNed.
As a result screen corruption, X lockups are observable. An example of kernel log of affected system with NV98 card where it was bisected:
nouveau 0000:01:00.0: gr: TRAP_M2MF 00000002 [IN]
nouveau 0000:01:00.0: gr: TRAP_M2MF 00320951 400007c0 00000000 04000000 nouveau 0000:01:00.0: gr: 00200000 [] ch 1 [000fbbe000 DRM] subc 4 class 5039 mthd 0100 data 00000000
nouveau 0000:01:00.0: fb: trapped read at 0040000000 on channel 1 [0fbbe000 DRM]
engine 00 [PGRAPH] client 03 [DISPATCH] subclient 04 [M2M_IN] reason 00000006 [NULL_DMAOBJ]
Fixes bug 105173 ("[MCP79][Regression] Unhandled NULL pointer dereference in nvkm_object_unmap since kernel 4.15")
https://bugs.freedesktop.org/show_bug.cgi?id=105173
--- drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c +1 -1
@@ -1354,7 +1354,7 @@ nvkm_vmm_get_locked(struct nvkm_vmm *vmm tail = this->addr + this->size;if (vmm->func->page_block && next && next->page != p) - tail =ALIGN_DOWN (addr, vmm->func->page_block); + tail =ALIGN_DOWN (tail, vmm->func->page_block);if (addr <= tail && tail - addr >= size) {rb_erase (&this->tree, &vmm->free);
Patches currently in stable-queue which might be from [email protected] are
queue-4.15/drm-nouveau-mmu-align_down-correct-variable.patch