6.12-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Zimmermann tzimmermann@suse.de
commit 76c332d119f9048c6e16b52359f401510f18b2ff upstream.
Fix an off-by-one error when setting the vblanking start in <VBLKSTR>. Commit d6460bd52c27 ("drm/mgag200: Add dedicated variables for blanking fields") switched the value from crtc_vdisplay to crtc_vblank_start, which DRM helpers copy from the former. The commit missed to subtract one though.
Reported-by: Wakko Warner wakko@animx.eu.org Closes: https://lore.kernel.org/dri-devel/CAMwc25rKPKooaSp85zDq2eh-9q4UPZD=RqSDBRp1f... Reported-by: Сергей afmerlord@gmail.com Closes: https://lore.kernel.org/all/5b193b75-40b1-4342-a16a-ae9fc62f245a@gmail.com/ Closes: https://bbs.archlinux.org/viewtopic.php?id=303819 Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: d6460bd52c27 ("drm/mgag200: Add dedicated variables for blanking fields") Cc: Thomas Zimmermann tzimmermann@suse.de Cc: Jocelyn Falempe jfalempe@redhat.com Cc: Dave Airlie airlied@redhat.com Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.12+ Reviewed-by: Jocelyn Falempe jfalempe@redhat.com Tested-by: Wakko Warner wakko@animx.eu.org Link: https://lore.kernel.org/r/20250416083847.51764-1-tzimmermann@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/mgag200/mgag200_mode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c @@ -223,7 +223,7 @@ void mgag200_set_mode_regs(struct mga_de vsyncstr = mode->crtc_vsync_start - 1; vsyncend = mode->crtc_vsync_end - 1; vtotal = mode->crtc_vtotal - 2; - vblkstr = mode->crtc_vblank_start; + vblkstr = mode->crtc_vblank_start - 1; vblkend = vtotal + 1;
linecomp = vdispend;