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Chen Li ede6b6bc43 drm/radeon: use writel to avoid gcc optimization v3
When using e8860(gcn1) on arm64, the kernel crashed on drm/radeon:

[   11.240414] pc : __memset+0x4c/0x188
[   11.244101] lr : radeon_uvd_get_create_msg+0x114/0x1d0 [radeon]
[   11.249995] sp : ffff00000d7eb700
[   11.253295] x29: ffff00000d7eb700 x28: ffff8001f632a868
[   11.258585] x27: 0000000000040000 x26: ffff00000de00000
[   11.263875] x25: 0000000000000125 x24: 0000000000000001
[   11.269168] x23: 0000000000000000 x22: 0000000000000005
[   11.274459] x21: ffff00000df24000 x20: ffff8001f74b4000
[   11.279753] x19: 0000000000124000 x18: 0000000000000020
[   11.285043] x17: 0000000000000000 x16: 0000000000000000
[   11.290336] x15: ffff000009309000 x14: ffffffffffffffff
[   11.290340] x13: ffff0000094b6f88 x12: ffff0000094b6bd2
[   11.290343] x11: ffff00000d7eb700 x10: ffff00000d7eb700
[   11.306246] x9 : ffff00000d7eb700 x8 : ffff00000df2402c
[   11.306254] x7 : 0000000000000000 x6 : ffff0000094b626a
[   11.306257] x5 : 0000000000000000 x4 : 0000000000000004
[   11.306262] x3 : ffffffffffffffff x2 : 0000000000000fd4
[   11.306265] x1 : 0000000000000000 x0 : ffff00000df2402c
[   11.306272] Call trace:
[   11.306316]  __memset+0x4c/0x188
[   11.306638]  uvd_v1_0_ib_test+0x70/0x1c0 [radeon]
[   11.306758]  radeon_ib_ring_tests+0x54/0xe0 [radeon]
...

Obviously, the __memset call is generated by gcc(8.3.1). It optimizes
this for loop into memset. But this may break on some platforms which
cannot map device memory correctly. So, just invoke `writel` to handle this.

v3 (chk): minor cleanups in code and commit message

Signed-off-by: Chen Li <chenli@uniontech.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2021-01-05 11:32:05 -05:00
arch Linux 5.10-rc3 2020-11-10 14:36:36 +01:00
block blk-mq: mark flush request as IDLE in flush_end_io() 2020-10-30 08:33:49 -06:00
certs
crypto
Documentation Merge tag 'drm-msm-next-2020-12-07' of https://gitlab.freedesktop.org/drm/msm into drm-next 2020-12-10 09:42:47 +10:00
drivers drm/radeon: use writel to avoid gcc optimization v3 2021-01-05 11:32:05 -05:00
fs Fixes for 5.10-rc3: 2020-11-08 10:23:07 -08:00
include Merge tag 'amd-drm-next-5.11-2020-12-09' of git://people.freedesktop.org/~agd5f/linux into drm-next 2020-12-10 16:55:53 +10:00
init linux-kselftest-kunit-5.10-rc1 2020-10-18 14:45:59 -07:00
ipc
kernel fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent 2020-11-08 11:18:39 -08:00
lib Fonts: Add charcount field to font_desc 2020-11-16 16:31:41 +01:00
LICENSES
mm Revert "mm: mmap: fix fput in error path v2" 2020-11-05 17:09:18 +01:00
net Networking fixes for 5.10-rc3, including fixes from wireless, can, 2020-11-06 11:50:28 -08:00
samples misc: mic: remove the MIC drivers 2020-10-28 19:12:03 +01:00
scripts Driver core documentation fixes for 5.10-rc3 2020-11-08 11:30:25 -08:00
security ima: Replace zero-length array with flexible-array member 2020-10-29 17:22:59 -05:00
sound ASoC: Fixes for v5.10 2020-11-05 18:19:32 +01:00
tools Linux 5.10-rc3 2020-11-10 14:36:36 +01:00
usr
virt kvm: x86/mmu: Support dirty logging for the TDP MMU 2020-10-23 03:42:13 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap MAINTAINERS: jarkko.sakkinen@linux.intel.com -> jarkko@kernel.org 2020-10-16 11:11:19 -07:00
COPYING
CREDITS MAINTAINERS: Move Sangbeom Kim to credits 2020-10-26 10:11:18 +01:00
Kbuild
Kconfig
MAINTAINERS Mediatek DRM Next for Linux 5.11-2 2020-12-03 13:23:57 +10:00
Makefile Linux 5.10-rc3 2020-11-08 16:10:16 -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.