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Tobias Klausmann e94c55b8e0 nouveau: Skip unvailable ttm page entries
Starting with commit f295c8cfec
("drm/nouveau: fix dma syncing warning with debugging on.")
the following oops occures:

   BUG: kernel NULL pointer dereference, address: 0000000000000000
   #PF: supervisor read access in kernel mode
   #PF: error_code(0x0000) - not-present page
   PGD 0 P4D 0
   Oops: 0000 [#1] PREEMPT SMP PTI
   CPU: 6 PID: 1013 Comm: Xorg.bin Tainted: G E     5.11.0-desktop-rc0+ #2
   Hardware name: Acer Aspire VN7-593G/Pluto_KLS, BIOS V1.11 08/01/2018
   RIP: 0010:nouveau_bo_sync_for_device+0x40/0xb0 [nouveau]
   Call Trace:
    nouveau_bo_validate+0x5d/0x80 [nouveau]
    nouveau_gem_ioctl_pushbuf+0x662/0x1120 [nouveau]
    ? nouveau_gem_ioctl_new+0xf0/0xf0 [nouveau]
    drm_ioctl_kernel+0xa6/0xf0 [drm]
    drm_ioctl+0x1f4/0x3a0 [drm]
    ? nouveau_gem_ioctl_new+0xf0/0xf0 [nouveau]
    nouveau_drm_ioctl+0x50/0xa0 [nouveau]
    __x64_sys_ioctl+0x7e/0xb0
    do_syscall_64+0x33/0x80
    entry_SYSCALL_64_after_hwframe+0x44/0xae
   ---[ end trace ccfb1e7f4064374f ]---
   RIP: 0010:nouveau_bo_sync_for_device+0x40/0xb0 [nouveau]

The underlying problem is not introduced by the commit, yet it uncovered the
underlying issue. The cited commit relies on valid pages. This is not given for
due to some bugs. For now, just warn and work around the issue by just ignoring
the bad ttm objects.
Below is some debug info gathered while debugging this issue:

nouveau 0000:01:00.0: DRM: ttm_dma->num_pages: 2048
nouveau 0000:01:00.0: DRM: ttm_dma->pages is NULL
nouveau 0000:01:00.0: DRM: ttm_dma: 00000000e96058e7
nouveau 0000:01:00.0: DRM: ttm_dma->page_flags:
nouveau 0000:01:00.0: DRM: ttm_dma:   Populated: 1
nouveau 0000:01:00.0: DRM: ttm_dma:   No Retry: 0
nouveau 0000:01:00.0: DRM: ttm_dma:   SG: 256
nouveau 0000:01:00.0: DRM: ttm_dma:   Zero Alloc: 0
nouveau 0000:01:00.0: DRM: ttm_dma:   Swapped: 0

Signed-off-by: Tobias Klausmann <tobias.klausmann@freenet.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210313222159.3346-1-tobias.klausmann@freenet.de
2021-03-19 10:38:31 +10:00
arch A set of irqchip updates: 2021-03-14 13:33:33 -07:00
block block: Discard page cache of zone reset target range 2021-03-11 11:49:25 -07:00
certs certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}ID 2021-01-21 16:16:10 +00:00
crypto crypto: mips/poly1305 - enable for all MIPS processors 2021-03-08 11:52:17 +01:00
Documentation A set of irqchip updates: 2021-03-14 13:33:33 -07:00
drivers nouveau: Skip unvailable ttm page entries 2021-03-19 10:38:31 +10:00
fs Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
include drm-misc-fixes for v5.12-rc4: 2021-03-19 10:21:48 +10:00
init Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
ipc fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
kernel prctl: fix PR_SET_MM_AUXV kernel stack leak 2021-03-14 14:33:27 -07:00
lib kasan: fix KASAN_STACK dependency for HW_TAGS 2021-03-13 11:27:31 -08:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
mm Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
net NFS Client Bugfixes for Linux 5.10-rc3 2021-03-12 14:19:35 -08:00
samples Merge git://git.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-03-09 17:15:56 -08:00
scripts kbuild: fix ld-version.sh to not be affected by locale 2021-03-13 11:12:13 +09:00
security Revert 95ebabde38 ("capabilities: Don't allow writing ambiguous v3 file capabilities") 2021-03-12 15:27:14 -06:00
sound ALSA: hda/hdmi: Cancel pending works before suspend 2021-03-10 12:52:01 +01:00
tools A single objtool fix to handle the PUSHF/POPF validation correctly for the 2021-03-14 13:15:55 -07:00
usr Kbuild updates for v5.12 2021-02-25 10:17:31 -08:00
virt KVM: x86/mmu: Consider the hva in mmu_notifier retry 2021-02-22 13:16:53 -05:00
.clang-format cxl for 5.12 2021-02-24 09:38:36 -08:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore clang-lto series for v5.12-rc1 2021-02-23 09:28:51 -08:00
.mailmap treewide: Miguel has moved 2021-02-26 09:41:03 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS treewide: Miguel has moved 2021-02-26 09:41:03 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
Makefile Linux 5.12-rc3 2021-03-14 14:41:02 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.