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Ville Syrjälä c08c364102 drm/i915: Bypass LMEMBAR/GTTMMADR for MTL stolen memory access
On MTL accessing stolen memory via the BARs is somehow borked,
and it can hang the machine. As a workaround let's bypass the
BARs and just go straight to DSMBASE/GSMBASE instead.

Note that on every other platform this itself would hang the
machine, but on MTL the system firmware is expected to relax
the access permission guarding stolen memory to enable this
workaround, and thus direct CPU accesses should be fine.

The raw stolen memory areas won't be passed to VMs so we'll
need to risk using the BAR there for the initial setup. Once
command submission is up we should switch to MI_UPDATE_GTT
which at least shouldn't hang the whole machine.

v2: Don't use direct GSM/DSM access on guests
    Add w/a number
v3: Check register 0x138914 to see if pcode did its job
    Add some debug prints

Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Tested-by: Paz Zcharya <pazz@chromium.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240202224340.30647-5-ville.syrjala@linux.intel.com
2024-02-07 01:58:54 +02:00
arch - Add a forgotten CPU vendor check in the AMD microcode post-loading 2023-12-10 10:53:55 -08:00
block block-6.7-2023-12-01 2023-12-02 06:39:30 +09:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto This push fixes a regression in ahash and hides the Kconfig sub-options for the jitter RNG. 2023-11-09 17:04:58 -08:00
Documentation amd-drm-next-6.8-2024-01-05: 2024-01-09 09:07:50 +10:00
drivers drm/i915: Bypass LMEMBAR/GTTMMADR for MTL stolen memory access 2024-02-07 01:58:54 +02:00
fs Char/Misc driver fixes for 6.7-rc5 2023-12-09 12:44:10 -08:00
include drm/i915: Add additional ARL PCI IDs 2024-01-18 15:24:32 -08:00
init As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
io_uring io_uring/af_unix: disable sending io_uring over sockets 2023-12-07 10:35:19 -07:00
ipc Many singleton patches against the MM code. The patch series which are 2023-11-02 19:38:47 -10:00
kernel - Make sure tasks are thawed exactly and only once to avoid their state 2023-12-10 11:09:16 -08:00
lib 31 hotfixes. 10 of these address pre-6.6 issues and are marked cc:stable. 2023-12-08 08:36:23 -08:00
LICENSES
mm mm/madvise: add cond_resched() in madvise_cold_or_pageout_pte_range() 2023-12-06 16:12:50 -08:00
net io_uring-6.7-2023-12-08 2023-12-08 12:32:38 -08:00
rust Kbuild updates for v6.7 2023-11-04 08:07:19 -10:00
samples Landlock updates for v6.7-rc1 2023-11-03 09:28:53 -10:00
scripts 31 hotfixes. 10 of these address pre-6.6 issues and are marked cc:stable. 2023-12-08 08:36:23 -08:00
security + Features 2023-11-03 09:48:17 -10:00
sound Two fixups 2023-12-12 13:06:29 +09:00
tools Generic: 2023-12-10 10:46:46 -08:00
usr
virt Revert "KVM: Prevent module exit until all VMs are freed" 2023-12-01 08:12:30 -08:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap .mailmap: add a new address mapping for Chester Lin 2023-12-06 16:12:45 -08:00
.rustfmt.toml
COPYING
CREDITS MAINTAINERS: drop Antti Palosaari 2023-12-06 16:12:49 -08:00
Kbuild
Kconfig
MAINTAINERS Introduce a new DRM driver for Intel GPUs 2023-12-22 10:36:21 +10:00
Makefile Linux 6.7-rc5 2023-12-10 14:33:40 -08:00
README

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.