> no longer have any video signal

You should be checking the journal for signs of GPU driver crashes.

> Full stack trace

Basically useless without debug symbols [1]. It's usually as simple as:

$ coredumpctl gdb (then answer y when it asks "Enable debuginfod for this session?")
(gdb) set logging enabled
(gdb) bt (or bt full)

Then post gdb.txt

[1] https://wiki.archlinux.org/title/Debugging/Getting_traces

The thing is that despite the crash, I see no error (error level) from the previous boot on the logs with `journalctl -b -1`.

However, I can see some warning level logs `journalctl -b -1 -p warning` (boot-1_warnings.log) for amdgpu, sddm-greeter, sddm-helper and sddm. (the 2h timing shift in the log timestamp is due to the hardware clock and the ntp sync in between during the init).

Note: the previous pastebin was actually from the LTS boot, not from the crashing vanilla boot.

Full last boot (journalctl -b -1) logs (boot-1_full.log).

Sorry, I hadn't the debug symbols installed, here is the proper gdb trace.

You are running some third party "Sweet" theme. This is not from Arch and therefore not supported...so this is definitely not an Arch packaging bug.

sddm[640]: Loading theme configuration from "/usr/share/sddm/themes/Sweet/theme.conf"

This has nothing to do with the theme used. The proof is I set back the default breeze theme and the same crash occurs.

Well, this is a fairly popular pkg and nobody else appears to be having the same problem. You should probably report this upstream. Please ensure to give them a backtrace with debug symbols.

Maybe this is not something between the kernel and SDDM but between the kernel and my graphic drivers for my specific hardware and the SDDM crash is just a consequence.

Upstream issue on SDDM tracker: https://github.com/sddm/sddm/issues/1761

The more I think, the more I start to believe the fact that I have no signal on linux 6.4 is unrelated to SDDM but related to the AMD graphics and maybe display port changes in linux 6.4 https://kernelnewbies.org/Linux_6.4. With the AMD graphics changes on 6.4 many people reports bad gaming performance but for my case it may as well end up with no signal at all. Anyway looks like an upstream issue. I have no clue hopw to troubleshoot that since I have no amdgpu error in journalctl.

Is the issue also present using the 6.5-rc1 from https://bbs.archlinux.org/viewtopic.php?pid=2108998#p2108998 you could also try 6.4.3 with amdgpu patches from https://bbs.archlinux.org/viewtopic.php?pid=2107227#p2107227
See also https://wiki.archlinux.org/title/Bisecting_bugs_with_Git

I have am having a weird issue with SDDM crashing on 6.4+ as well, with amdgpu drivers. GDM has no issues. Not sure if it is specific to certain hardware configs (7900xt, 12700k). I also haven't tried changing sddm back to a x11 session yet. Just been fine using gdm for the time being. I can boot on older kernels before 6.4 as well.
Im new to the community and have been using arch for about 7 months now so it could be something I just messed up on my end. Your experience does seem extremely similar to mine, so I thought Id share.

@Taylor: Unrelated to X11 or wayland, happens when both are predefined as default and anyway the crash occurs before opening a session.

Please try with linux 6.4.4. If the issue is still present please try 6.5-rc2 or rc3 if available. If that still has the issue please try [1] if the issue is still present please bisect [2] between 6.3 and 6.4 and report the issue upstream [3].

[1] https://gitlab.freedesktop.org/agd5f/linux
[2] https://wiki.archlinux.org/title/Kernel#Debugging_regressions
[3] https://gitlab.freedesktop.org/drm/amd/-/issues

linux-6.4.4 and linux-zen-6.4.4 not working.
linux-mainline (6.5-rc2) not working either (kernel drm warning logs attached).
linux-drm-tip-git (6.5.r1200134.003f860e5577-1) and linux-drm-next-git (6.4.r1188951.6725f3322807-1) are not working either.
linux-amd-drm-next (6.4.2023.05.31-1) and linux-amd-staging-drm-next-git (6.2.r1160341.2514cae86fce-1) are not working. Note: having inux-amd-staging-drm-next-git not working while it is 6.2.x indicates that the crash must comes from an AMDGPU update that was introduces on 6.4.0.

Since none of the kernel worked, I have to git bisect to report upstream.
If I understand correctly to bisect I'll have to re-build the kernel from git for each commit. Since building `linux-amd-staging-drm-next-git` took me an entire day, bisecting will take me an eternity. I know all unnecessary drivers (network, sound, printer, etc.) could be disabled using modprobed-db to speed up the build time but I don't have the skills to do that.

$ git bisect start
status: waiting for both good and bad commits
$ git bisect bad v6.4
status: waiting for good commit(s), bad commit known
$ git bisect good v6.3
Bisecting: 8012 revisions left to test after this (roughly 13 steps)
[d42b1c47570eb2ed818dc3fe94b2678124af109d] Merge tag 'devicetree-for-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

https://drive.google.com/file/d/1LgdkT9cgo4msW7A9ws09rNLlvy3jj-8_/view?usp=sharing linux-6.3.r7998.gd42b1c47570e-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1yjHu9Xsn5Be3u9f9Z-oXLZkQDElSNim2/view?usp=sharing linux-headers-6.3.r7998.gd42b1c47570e-1-x86_64.pkg.tar.zst

It doesn't work with linux-6.3.r7998.gd42b1c47570e.

$ git bisect bad
Bisecting: 4005 revisions left to test after this (roughly 12 steps)
[088e0c188513b58a0056a488cf5b7df094a8a48a] Merge tag 'platform-drivers-x86-v6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

https://drive.google.com/file/d/1AwDtQfg6wNgNM5v44-q_-0T3eK1tnPU4/view?usp=sharing linux-6.3.r3992.g088e0c188513-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1HjykYgs5C1A0AGGAbPd4fbFDXLR21euD/view?usp=sharing linux-headers-6.3.r3992.g088e0c188513-1-x86_64.pkg.tar.zst

6.4.6 not working.
linux-6.3.r3992.g088e0c188513 not working.
6.1.39-1-lts working.

$ git bisect bad
Bisecting: 2178 revisions left to test after this (roughly 11 steps)
[736b378b29d89c8c3567fa4b2e948be5568aebb8] Merge tag 'slab-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

https://drive.google.com/file/d/117YtgDAR0dVFyOnr3OG27lKR1TABhN59/view?usp=sharing linux-6.3.r1813.g736b378b29d8-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1tzLQqSeJLInvCj5mn1hE6aDgwdXCuKT6/view?usp=sharing linux-headers-6.3.r1813.g736b378b29d8-1-x86_64.pkg.tar.zst

6.4.7 not working.
linux-6.3.r1813.g736b378b29d8 IS working!

$ git bisect good
Bisecting: 1079 revisions left to test after this (roughly 10 steps)
[52b113e968be66b57f792b2e2a9b8b77f382bd5f] Merge tag 'drm-misc-next-2023-04-06' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

https://drive.google.com/file/d/1edca4oXfpK8eaILq9FqtemtANMO2WaVM/view?usp=sharing linux-6.3rc4.r1099.g52b113e968be-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1xf7AQFpz8SV3lRP091bPnADKdQ3TO5N8/view?usp=sharing linux-headers-6.3rc4.r1099.g52b113e968be-1-x86_64.pkg.tar.zst

linux-6.3rc4.r1099.g52b113e968be is not working.

$ git bisect bad
Bisecting: 539 revisions left to test after this (roughly 9 steps)
[c6265f5c2f502e442c4f339f121bedbc990c12e7] Merge tag 'drm-misc-next-2023-03-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

https://drive.google.com/file/d/1b-rVBiw_xDE1QtfKU5J0rXB9YEA1WP5v/view?usp=sharing linux-6.3rc2.r559.gc6265f5c2f50-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1AmbGjZq0q_h2x3F3RDJKVH6C91zRKni1/view?usp=sharing linux-headers-6.3rc2.r559.gc6265f5c2f50-1-x86_64.pkg.tar.zst

linux-6.3rc2.r559.gc6265f5c2f50 is not working.

$ git bisect bad
Bisecting: 261 revisions left to test after this (roughly 8 steps)
[8bf6e20253b2d2b614f2c0b491f840e956fa6b05] Merge tag 'drm-intel-next-2023-03-07' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

https://drive.google.com/file/d/1yyheaxz27qtQqLIonwg1ylBjctradA51/view?usp=sharing linux-6.3rc2.r297.g8bf6e20253b2-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1N_FOiy9kJ1UYQFMypETkdMymFPBmM5qm/view?usp=sharing linux-headers-6.3rc2.r297.g8bf6e20253b2-1-x86_64.pkg.tar.zst

linux-6.3rc2.r297.g8bf6e20253b2 IS working.

$ git bisect good
Bisecting: 130 revisions left to test after this (roughly 7 steps)
[3b4723de0d9be3f2a1730c164987b6e0f38d7bb7] drm/amd/pm: bump SMU 13.0.4 driver_if header version

https://drive.google.com/file/d/1Kj7VCv4zJEokJOw0Jvy2rwfQM4Aa9GmW/view?usp=sharing linux-6.2rc6.r1646.g3b4723de0d9b-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1R4q9z4amUlXnXvEVErrX8LTCgOt3Sofg/view?usp=sharing linux-headers-6.2rc6.r1646.g3b4723de0d9b-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1646.g3b4723de0d9b doesn't work.

$ git bisect bad
Bisecting: 65 revisions left to test after this (roughly 6 steps)
[55f86c2b030463f8c98e66911f4548a1fc0666ee] drm/amdgpu: add psp early init for PSP 13.0.6

https://drive.google.com/file/d/1Biv2zUGvQO7fvkzYkpG32CmmbLbc-P4L/view?usp=sharing linux-6.2rc6.r1580.g55f86c2b0304-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1vZ-NV2u7VbbKuLPQNqLDv213IF-bQDY_/view?usp=sharing linux-headers-6.2rc6.r1580.g55f86c2b0304-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1580.g55f86c2b0304 is working.

$ git bisect good
Bisecting: 32 revisions left to test after this (roughly 5 steps)
[97fa4dfa66fdd52ad3d0c9fadeaaa1e87605bac7] drm/amd/display: Enable HostVM based on rIOMMU active

https://drive.google.com/file/d/1nGa2IBsYUkjK3NvMgyWnv0XYoXZblNm1/view?usp=sharing linux-6.2rc6.r1613.g97fa4dfa66fd-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1woAMPyVXaS2L56ZHv2fqyuiWfWmS2nYj/view?usp=sharing linux-headers-6.2rc6.r1613.g97fa4dfa66fd-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1613.g97fa4dfa66fd is NOT working.

$ git bisect bad
Bisecting: 16 revisions left to test after this (roughly 4 steps)
[11efe095dfe0768f5b248b77a84e5aa748f14204] drm/amd/display: Fix no-DCN build

https://drive.google.com/file/d/1PxLohvmq_v_ffsl_3oU6nUA9lUGO2brn/view?usp=sharing linux-6.2rc6.r1596.g11efe095dfe0-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1BDlN6Li4utr0IAS8UP5RnEAoa1xwcgYK/view?usp=sharing linux-headers-6.2rc6.r1596.g11efe095dfe0-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1596.g11efe095dfe0 IS working.

$ git bisect good
Bisecting: 8 revisions left to test after this (roughly 3 steps)
[202a3816f37e49ab490ff4582f1fb34390e5824e] drm/amd/display: move dc_link functions in protocols folder to dc_link_exports

https://drive.google.com/file/d/1HXdKUcXRqTMMN_vM8uWmgdeUixATaMs6/view?usp=sharing linux-6.2rc6.r1604.g202a3816f37e-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1UmPqBXokJ19gYgrl49FvGNnr_3m-OBRT/view?usp=sharing linux-headers-6.2rc6.r1604.g202a3816f37e-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1604.g202a3816f37e is NOT working.

$ git bisect bad
Bisecting: 3 revisions left to test after this (roughly 2 steps)
[84c03df58d8bbf77feb2f199f10dbe8f7f72c782] drm/amd/display: Build DSC without DCN config

https://drive.google.com/file/d/13NmncQmyBVIryVfxGX592U0hLgWBG6Xa/view?usp=sharing linux-6.2rc6.r1600.g84c03df58d8b-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1WzvebIv3E1cJ9bHmrBXnODo0J0r5Ua83/view?usp=sharing linux-headers-6.2rc6.r1600.g84c03df58d8b-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1600.g84c03df58d8b is NOT working.

Note: I see my bootloader (rEFInd) resolution at 1920*1080 in both cases, but it seems that I see the systemd boot logs at 19020*1080 on failing kernels and at a default 640*480 or something for all working kernels. It may not be a coincidence and is maybe related to the video driver issue.

$ git bisect bad
Bisecting: 1 revision left to test after this (roughly 1 step)
[1e88eb1b2c259994d034b0833cb489105a984ebb] drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP

https://drive.google.com/file/d/1qsol06sNCUX5zoDSoYZZHQ31GwfAVGv4/view?usp=sharing linux-6.2rc6.r1598.g1e88eb1b2c25-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1lbYqsR-sHJ7jKtuMtZg8-6jlqXWd59zB/view?usp=sharing linux-headers-6.2rc6.r1598.g1e88eb1b2c25-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1598.g1e88eb1b2c25 is NOT working.

$ git bisect bad
Bisecting: 0 revisions left to test after this (roughly 0 steps)
[ab487ea8910d2a84f851cb87f2cb49adcb5b774b] drm/amd/display: fix typo in dc_dsc_config_options structure

https://drive.google.com/file/d/12JZjkfexvzS_BmxTTbdYDjG5naeHVg0I/view?usp=sharing linux-6.2rc6.r1597.gab487ea8910d-1-x86_64.pkg.tar.zst
https://drive.google.com/file/d/1sM8qB7Auk4HNr7tUHHUaBpZaoswF1FD5/view?usp=sharing linux-headers-6.2rc6.r1597.gab487ea8910d-1-x86_64.pkg.tar.zst

linux-6.2rc6.r1597.gab487ea8910d IS working.

$ git bisect good
1e88eb1b2c259994d034b0833cb489105a984ebb is the first bad commit
commit 1e88eb1b2c259994d034b0833cb489105a984ebb
Author: Harry Wentland <harry.wentland@amd.com>
Date: Mon Feb 13 11:19:31 2023 -0500

drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP

[Why & How]
There is no reason we still need a config option for this.

Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/Kconfig | 6 --
drivers/gpu/drm/amd/display/Makefile | 4 -
drivers/gpu/drm/amd/display/amdgpu_dm/Makefile | 2 -
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 24 -----
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 4 -
.../drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 11 +--
.../amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 -
drivers/gpu/drm/amd/display/dc/Makefile | 2 -
drivers/gpu/drm/amd/display/dc/core/dc.c | 4 -
.../gpu/drm/amd/display/dc/core/dc_link_exports.c | 2 -
drivers/gpu/drm/amd/display/dc/dc.h | 15 +--
drivers/gpu/drm/amd/display/dc/dc_types.h | 6 --
.../display/dc/dcn32/dcn32_dio_stream_encoder.c | 2 -
drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c | 2 +-
drivers/gpu/drm/amd/display/dc/inc/core_types.h | 2 -
drivers/gpu/drm/amd/display/dc/inc/link.h | 2 -
.../gpu/drm/amd/display/dc/link/link_detection.c | 10 --
drivers/gpu/drm/amd/display/dc/link/link_dpms.c | 10 --
.../display/dc/link/protocols/link_dp_training.c | 2 -
.../gpu/drm/amd/display/include/hdcp_msg_types.h | 103 +++++++++++++++++++++
drivers/gpu/drm/amd/display/include/hdcp_types.h | 103 ---------------------
.../gpu/drm/amd/display/modules/hdcp/hdcp_log.h | 2 -
22 files changed, 106 insertions(+), 217 deletions(-)
create mode 100644 drivers/gpu/drm/amd/display/include/hdcp_msg_types.h
delete mode 100644 drivers/gpu/drm/amd/display/include/hdcp_types.h

$ git bisect log
git bisect start
# status: waiting for both good and bad commits
# bad: [6995e2de6891c724bfeb2db33d7b87775f913ad1] Linux 6.4
git bisect bad 6995e2de6891c724bfeb2db33d7b87775f913ad1
# status: waiting for good commit(s), bad commit known
# good: [457391b0380335d5e9a5babdec90ac53928b23b4] Linux 6.3
git bisect good 457391b0380335d5e9a5babdec90ac53928b23b4
# bad: [d42b1c47570eb2ed818dc3fe94b2678124af109d] Merge tag 'devicetree-for-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
git bisect bad d42b1c47570eb2ed818dc3fe94b2678124af109d
# bad: [088e0c188513b58a0056a488cf5b7df094a8a48a] Merge tag 'platform-drivers-x86-v6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
git bisect bad 088e0c188513b58a0056a488cf5b7df094a8a48a
# good: [736b378b29d89c8c3567fa4b2e948be5568aebb8] Merge tag 'slab-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
git bisect good 736b378b29d89c8c3567fa4b2e948be5568aebb8
# bad: [52b113e968be66b57f792b2e2a9b8b77f382bd5f] Merge tag 'drm-misc-next-2023-04-06' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
git bisect bad 52b113e968be66b57f792b2e2a9b8b77f382bd5f
# bad: [c6265f5c2f502e442c4f339f121bedbc990c12e7] Merge tag 'drm-misc-next-2023-03-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
git bisect bad c6265f5c2f502e442c4f339f121bedbc990c12e7
# good: [8bf6e20253b2d2b614f2c0b491f840e956fa6b05] Merge tag 'drm-intel-next-2023-03-07' of git://anongit.freedesktop.org/drm/drm-intel into drm-next
git bisect good 8bf6e20253b2d2b614f2c0b491f840e956fa6b05
# bad: [3b4723de0d9be3f2a1730c164987b6e0f38d7bb7] drm/amd/pm: bump SMU 13.0.4 driver_if header version
git bisect bad 3b4723de0d9be3f2a1730c164987b6e0f38d7bb7
# good: [55f86c2b030463f8c98e66911f4548a1fc0666ee] drm/amdgpu: add psp early init for PSP 13.0.6
git bisect good 55f86c2b030463f8c98e66911f4548a1fc0666ee
# bad: [97fa4dfa66fdd52ad3d0c9fadeaaa1e87605bac7] drm/amd/display: Enable HostVM based on rIOMMU active
git bisect bad 97fa4dfa66fdd52ad3d0c9fadeaaa1e87605bac7
# good: [11efe095dfe0768f5b248b77a84e5aa748f14204] drm/amd/display: Fix no-DCN build
git bisect good 11efe095dfe0768f5b248b77a84e5aa748f14204
# bad: [202a3816f37e49ab490ff4582f1fb34390e5824e] drm/amd/display: move dc_link functions in protocols folder to dc_link_exports
git bisect bad 202a3816f37e49ab490ff4582f1fb34390e5824e
# bad: [84c03df58d8bbf77feb2f199f10dbe8f7f72c782] drm/amd/display: Build DSC without DCN config
git bisect bad 84c03df58d8bbf77feb2f199f10dbe8f7f72c782
# bad: [1e88eb1b2c259994d034b0833cb489105a984ebb] drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP
git bisect bad 1e88eb1b2c259994d034b0833cb489105a984ebb
# good: [ab487ea8910d2a84f851cb87f2cb49adcb5b774b] drm/amd/display: fix typo in dc_dsc_config_options structure
git bisect good ab487ea8910d2a84f851cb87f2cb49adcb5b774b
# first bad commit: [1e88eb1b2c259994d034b0833cb489105a984ebb] drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP

Although the bisection result seems a bit odd to me please report the issue along with bisection result on https://gitlab.freedesktop.org/drm/amd/-/issues