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Stephan Gerhold b71717735b drm/msm/gpu: Fix crash when throttling GPU immediately during boot
There is a small chance that the GPU is already hot during boot. In that
case, the call to of_devfreq_cooling_register() will immediately try to
apply devfreq cooling, as seen in the following crash:

  Unable to handle kernel paging request at virtual address 0000000000014110
  pc : a6xx_gpu_busy+0x1c/0x58 [msm]
  lr : msm_devfreq_get_dev_status+0xbc/0x140 [msm]
  Call trace:
   a6xx_gpu_busy+0x1c/0x58 [msm] (P)
   devfreq_simple_ondemand_func+0x3c/0x150
   devfreq_update_target+0x44/0xd8
   qos_max_notifier_call+0x30/0x84
   blocking_notifier_call_chain+0x6c/0xa0
   pm_qos_update_target+0xd0/0x110
   freq_qos_apply+0x3c/0x74
   apply_constraint+0x88/0x148
   __dev_pm_qos_update_request+0x7c/0xcc
   dev_pm_qos_update_request+0x38/0x5c
   devfreq_cooling_set_cur_state+0x98/0xf0
   __thermal_cdev_update+0x64/0xb4
   thermal_cdev_update+0x4c/0x58
   step_wise_manage+0x1f0/0x318
   __thermal_zone_device_update+0x278/0x424
   __thermal_cooling_device_register+0x2bc/0x308
   thermal_of_cooling_device_register+0x10/0x1c
   of_devfreq_cooling_register_power+0x240/0x2bc
   of_devfreq_cooling_register+0x14/0x20
   msm_devfreq_init+0xc4/0x1a0 [msm]
   msm_gpu_init+0x304/0x574 [msm]
   adreno_gpu_init+0x1c4/0x2e0 [msm]
   a6xx_gpu_init+0x5c8/0x9c8 [msm]
   adreno_bind+0x2a8/0x33c [msm]
   ...

At this point we haven't initialized the GMU at all yet, so we cannot read
the GMU registers inside a6xx_gpu_busy(). A similar issue was fixed before
in commit 6694482a70 ("drm/msm: Avoid unclocked GMU register access in
6xx gpu_busy"): msm_devfreq_init() does call devfreq_suspend_device(), but
unlike msm_devfreq_suspend(), it doesn't set the df->suspended flag
accordingly. This means the df->suspended flag does not match the actual
devfreq state after initialization and msm_devfreq_get_dev_status() will
end up accessing GMU registers, causing the crash.

Fix this by setting df->suspended correctly during initialization.

Cc: stable@vger.kernel.org
Fixes: 6694482a70 ("drm/msm: Avoid unclocked GMU register access in 6xx gpu_busy")
Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/650772/
Signed-off-by: Rob Clark <robdclark@chromium.org>
2025-05-04 09:20:28 -07:00
arch bpf-fixes 2025-04-12 12:48:10 -07:00
block treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto This push fixes reverts the multibuffer hash testing as it is buggy. 2025-04-02 09:14:59 -07:00
Documentation dt-bindings: display: msm: document DSI controller and phy on SA8775P 2025-05-02 03:54:03 +03:00
drivers drm/msm/gpu: Fix crash when throttling GPU immediately during boot 2025-05-04 09:20:28 -07:00
fs Changes since last update: 2025-04-13 10:52:04 -07:00
include drm/panthor: Add driver IOCTL for setting BO labels 2025-04-23 10:35:35 +02:00
init Miscellaneous scheduler fixes/updates: 2025-04-06 10:44:58 -07:00
io_uring io_uring/kbuf: reject zero sized provided buffers 2025-04-07 07:51:23 -06:00
ipc treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
kernel tracing fixes for v6.15 2025-04-12 15:37:40 -07:00
lib vsprintf: Use %p4chR instead of %p4cn for reading data in reversed host ordering 2025-04-29 09:29:33 -04:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm Disable SLUB_TINY for build testing 2025-04-06 10:00:04 -07:00
net bpf-fixes 2025-04-12 12:48:10 -07:00
rust Kbuild updates for v6.15 2025-04-05 15:46:50 -07:00
samples treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
scripts lib/vsprintf: Add support for generic FourCCs by extending %p4cc 2025-04-21 10:18:30 -04:00
security mseal sysmap: kernel config and header change 2025-04-01 15:17:14 -07:00
sound soundwire fix for 6.15-rc1 2025-04-06 12:04:53 -07:00
tools memblock: fix build of memblock test 2025-04-13 07:11:33 -07:00
usr kbuild: hdrcheck: fix cross build with clang 2025-03-05 04:06:45 +09:00
virt ARM: 2025-04-08 13:47:55 -07:00
.clang-format drm/vkms: Allow to attach connectors and encoders 2025-03-07 10:58:28 +01:00
.clippy.toml rust: give Clippy the minimum supported Rust version 2025-01-10 00:17:25 +01:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: Create intermediate vmlinux build with relocations preserved 2025-03-17 00:29:50 +09:00
.mailmap mailmap: add an entry for Nicolas Schier 2025-04-01 15:20:45 -07:00
.rustfmt.toml
COPYING
CREDITS Including fixes from netfilter. 2025-04-04 09:15:35 -07:00
Kbuild drm: ensure drm headers are self-contained and pass kernel-doc 2025-02-12 10:44:43 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS MAINTAINERS: add entry for Sitronix ST7571 LCD Controller 2025-04-23 21:47:23 +02:00
Makefile Linux 6.15-rc2 2025-04-13 11:54:49 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.