Hi Greg, On Wed, Jan 19, 2022 at 12:28 PM Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Jan 19, 2022 at 12:22:55PM +0100, Greg Kroah-Hartman wrote: > > On Wed, Jan 19, 2022 at 12:08:39PM +0100, Helge Deller wrote: > > > This reverts commit 39aead8373b3c20bb5965c024dfb51a94e526151. > > > > > > Revert this patch. This patch started to introduce the regression that > > > all hardware acceleration of more than 35 existing fbdev drivers were > > > bypassed and thus fbcon console output for those was dramatically slowed > > > down by factor of 10 and more. > > > > > > Reverting this commit has no impact on DRM, since none of the DRM drivers are > > > tagged with the acceleration flags FBINFO_HWACCEL_COPYAREA, > > > FBINFO_HWACCEL_FILLRECT or others. > > > > > > Signed-off-by: Helge Deller <deller@xxxxxx> > > As for "why", I think there was a number of private bugs that were > > reported in this code, which is why it was removed. I do not think it > > can be safely added back in without addressing them first. Let me go > > dig through my email to see if I can find them... > > Ah, no, that was just the soft scrollback code I was thinking of, which So the bugs argument is moot. > was a different revert and is still gone, thankfully :) FTR, not everyone else was thankful about that one... > This one was just removed because Daniel noticed that only 3 drivers > used this (nouveau, omapdrm, and gma600), so this shouldn't have caused > any regressions in any other drivers like you are reporting here. > > So perhaps this regression is caused by something else? 1. Daniel's patch was not CCed to linux-fbdev, 2. When I discovered the patch, I pointed out that the premise of 3 drivers was not true, and that it affects 32 more fbdev drivers[1] . The patch was applied regardless. 3. When the patch was suggested for backporting, I pointed out the same[2]. The patch was backported regardless. [1] https://lore.kernel.org/r/alpine.DEB.2.22.394.2010311116530.379363@xxxxxxxxxxxxxx/ [2] https://lore.kernel.org/r/CAMuHMdXRgam2zahPEGcw8+76Xm-0AO-Ci9-YmVa5JpTKVHphRw@xxxxxxxxxxxxxx/ Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
