git bisect start
# Status: warte auf guten und schlechten Commit
# good: [3a8660878839faadb4f1a6dd72c3179c1df56787] Linux 6.18-rc1
git bisect good 3a8660878839faadb4f1a6dd72c3179c1df56787
# Status: warte auf schlechten Commit, 1 guter Commit bekannt
# bad: [211ddde0823f1442e4ad052a2f30f050145ccada] Linux 6.18-rc2
git bisect bad 211ddde0823f1442e4ad052a2f30f050145ccada
# bad: [1422424187a548c24825645410fb7f691c2df47f] Merge tag 'sound-6.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
git bisect bad 1422424187a548c24825645410fb7f691c2df47f
# good: [05de41f3e26237bc34822268f958be1820bf968b] Merge tag 'v6.18-rc1-smb-server-fixes' of git://git.samba.org/ksmbd
git bisect good 05de41f3e26237bc34822268f958be1820bf968b
# bad: [62cab426d0e340cd38893227c279705cc9e8416a] Merge tag 'drm-xe-fixes-2025-10-16' of https://gitlab.freedesktop.org/drm/xe/kernel into drm-fixes
git bisect bad 62cab426d0e340cd38893227c279705cc9e8416a
# good: [520133b0ba97fbc4b2b92daa66fed9b279550021] Merge tag 'amd-drm-fixes-6.18-2025-10-16' of https://gitlab.freedesktop.org/agd5f/linux into drm-fixes
git bisect good 520133b0ba97fbc4b2b92daa66fed9b279550021
# bad: [d6dd930a6b3d177cda9aa8dfdcc6b2c7dda4d78a] Merge tag 'drm-misc-fixes-2025-10-16' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes
git bisect bad d6dd930a6b3d177cda9aa8dfdcc6b2c7dda4d78a
# good: [fd6e385528d8f85993b7bfc6430576136bb14c65] accel/qaic: Fix bootlog initialization ordering
git bisect good fd6e385528d8f85993b7bfc6430576136bb14c65
# bad: [6f719373b943a955fee6fc2012aed207b65e2854] drm/ast: Blank with VGACR17 sync enable, always clear VGACRB6 sync off
git bisect bad 6f719373b943a955fee6fc2012aed207b65e2854
# good: [52e59f7740ba23bbb664914967df9a00208ca10c] accel/qaic: Synchronize access to DBC request queue head & tail pointer
git bisect good 52e59f7740ba23bbb664914967df9a00208ca10c
# first bad commit: [6f719373b943a955fee6fc2012aed207b65e2854] drm/ast: Blank with VGACR17 sync enable, always clear VGACRB6 sync off



commit 6f719373b943a955fee6fc2012aed207b65e2854
Author: Thomas Zimmermann <tzimmermann@suse.de>
Date:   Tue Oct 14 10:46:34 2025 +0200

    drm/ast: Blank with VGACR17 sync enable, always clear VGACRB6 sync off

    Blank the display by disabling sync pulses with VGACR17<7>. Unblank
    by reenabling them. This VGA setting should be supported by all Aspeed
    hardware.

    Ast currently blanks via sync-off bits in VGACRB6. Not all BMCs handle
    VGACRB6 correctly. After disabling sync during a reboot, some BMCs do
    not reenable it after the soft reset. The display output remains dark.
    When the display is off during boot, some BMCs set the sync-off bits in
    VGACRB6, so the display remains dark. Observed with  Blackbird AST2500
    BMCs. Clearing the sync-off bits unconditionally fixes these issues.

    Also do not modify VGASR1's SD bit for blanking, as it only disables GPU
    access to video memory.

    v2:
    - init vgacrb6 correctly (Jocelyn)

    Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
    Fixes: ce3d99c83495 ("drm: Call drm_atomic_helper_shutdown() at shutdown time for misc drivers")
    Tested-by: Nick Bowler <nbowler@draconx.ca>
    Reported-by: Nick Bowler <nbowler@draconx.ca>
    Closes: https://lore.kernel.org/dri-devel/wpwd7rit6t4mnu6kdqbtsnk5bhftgslio6e2jgkz6kgw6cuvvr@xbfswsczfqsi/
    Cc: Douglas Anderson <dianders@chromium.org>
    Cc: Dave Airlie <airlied@redhat.com>
    Cc: Thomas Zimmermann <tzimmermann@suse.de>
    Cc: Jocelyn Falempe <jfalempe@redhat.com>
    Cc: dri-devel@lists.freedesktop.org
    Cc: <stable@vger.kernel.org> # v6.7+
    Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
    Link: https://lore.kernel.org/r/20251014084743.18242-1-tzimmermann@suse.de