linux_dsm_epyc7002/drivers/video/fbdev
Daniel Vetter 397971e1d8 fbcon: Disable accelerated scrolling
commit 39aead8373b3c20bb5965c024dfb51a94e526151 upstream.

So ever since syzbot discovered fbcon, we have solid proof that it's
full of bugs. And often the solution is to just delete code and remove
features, e.g.  50145474f6 ("fbcon: remove soft scrollback code").

Now the problem is that most modern-ish drivers really only treat
fbcon as an dumb kernel console until userspace takes over, and Oops
printer for some emergencies. Looking at drm drivers and the basic
vesa/efi fbdev drivers shows that only 3 drivers support any kind of
acceleration:

- nouveau, seems to be enabled by default
- omapdrm, when a DMM remapper exists using remapper rewriting for
  y/xpanning
- gma500, but that is getting deleted now for the GTT remapper trick,
  and the accelerated copyarea never set the FBINFO_HWACCEL_COPYAREA
  flag, so unused (and could be deleted already I think).

No other driver supportes accelerated fbcon. And fbcon is the only
user of this accel code (it's not exposed as uapi through ioctls),
which means we could garbage collect fairly enormous amounts of code
if we kill this.

Plus because syzbot only runs on virtual hardware, and none of the
drivers for that have acceleration, we'd remove a huge gap in testing.
And there's no other even remotely comprehensive testing aside from
syzbot.

This patch here just disables the acceleration code by always
redrawing when scrolling. The plan is that once this has been merged
for well over a year in released kernels, we can start to go around
and delete a lot of code.

v2:
- Drop a few more unused local variables, somehow I missed the
compiler warnings (Sam)
- Fix typo in comment (Jiri)
- add a todo entry for the cleanup (Thomas)

v3: Remove more unused variables (0day)

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: nouveau@lists.freedesktop.org
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Peilin Ye <yepeilin.cs@gmail.com>
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Peter Rosin <peda@axentia.se>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201029132229.4068359-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-06 14:56:51 +01:00
..
aty fbdev: aty: remove CONFIG_PM container 2020-09-18 14:45:44 +02:00
core fbcon: Disable accelerated scrolling 2021-01-06 14:56:51 +01:00
geode fbdev: lxfb: use generic power management 2020-09-08 13:33:10 +02:00
i810 video: fbdev: i810: use true,false for bool variables 2020-05-06 19:29:10 +02:00
intelfb drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
kyro video: fbdev: kyro: remove set but not used 'ulCoreClock' 2020-09-08 13:33:31 +02:00
matrox treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
mb862xx video: fbdev: mb862xx: remove set but not used variable 'mdr' 2020-04-08 12:09:15 +02:00
mmp treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
nvidia Merge drm/drm-next into drm-misc-next 2020-09-14 18:11:40 +02:00
omap treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
omap2 omapfb: fix spelling mistake "propert" -> "property" 2020-09-08 13:33:05 +02:00
riva treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
savage fbdev: savagefb: use generic power management 2020-09-08 13:33:15 +02:00
sis Merge drm/drm-next into drm-misc-next 2020-09-14 18:11:40 +02:00
vermilion remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
via Merge drm/drm-next into drm-misc-next 2020-09-14 18:11:40 +02:00
68328fb.c video/fbdev/68328fb: Remove dead code 2020-01-03 14:27:43 +01:00
acornfb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
acornfb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
amba-clcd.c Partially revert "video: fbdev: amba-clcd: Retire elder CLCD driver" 2020-09-30 16:37:39 +02:00
amifb.c video: fbdev: amifb: add FIXMEs about {put,get}_user() failures 2020-07-10 16:17:20 +02:00
arcfb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
arkfb.c fbdev: arkfb: use generic power management 2020-09-08 13:33:20 +02:00
asiliantfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
atafb_iplan2p2.c fbdev: atafb: Remove obsolete module support 2019-04-01 17:46:55 +02:00
atafb_iplan2p4.c fbdev: atafb: Remove obsolete module support 2019-04-01 17:46:55 +02:00
atafb_iplan2p8.c fbdev: atafb: Remove obsolete module support 2019-04-01 17:46:55 +02:00
atafb_mfb.c fbdev: atafb: Remove obsolete module support 2019-04-01 17:46:55 +02:00
atafb_utils.h
atafb.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
atafb.h
atmel_lcdfb.c video: fbdev: atmel_lcdfb: fix return error code in atmel_lcdfb_of_init() 2020-12-30 11:53:13 +01:00
au1100fb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
au1100fb.h au1100fb: fix DMA API abuse 2019-06-03 16:00:08 +02:00
au1200fb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
au1200fb.h
broadsheetfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
bt431.h
bt455.h
bw2.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
c2p_core.h fbdev: c2p: Use BUILD_BUG() instead of custom solution 2020-03-09 11:12:19 +01:00
c2p_iplan2.c
c2p_planar.c
c2p.h
carminefb_regs.h
carminefb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
carminefb.h
cg3.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
cg6.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
cg14.c fbdev: cg14fb: use resource_size 2020-01-15 17:31:50 +01:00
chipsfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
cirrusfb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
clps711x-fb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
cobalt_lcdfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
controlfb.c powerpc fixes for 5.9 #4 2020-08-30 10:56:12 -07:00
controlfb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
cyber2000fb.c fbdev: cyber2000fb: use generic power management 2020-09-08 13:33:16 +02:00
cyber2000fb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
da8xx-fb.c fbdev: da8xx-fb: go to proper label on error handling paths in probe 2020-07-10 16:17:28 +02:00
dnfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
edid.h
efifb.c efi: avoid error message when booting under Xen 2020-08-20 06:26:22 +02:00
ep93xx-fb.c video: fbdev: Replace HTTP links with HTTPS ones 2020-07-20 11:47:29 +02:00
ffb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
fm2fb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
fsl-diu-fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
g364fb.c fbdev/g364fb: Fix build failure 2020-02-19 10:58:22 -08:00
gbefb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
goldfishfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
grvga.c video: fbdev: Replace HTTP links with HTTPS ones 2020-07-20 11:47:29 +02:00
gxt4500.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
hecubafb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
hgafb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
hitfb.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
hpfb.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
hyperv_fb.c hyperv-fixes for 5.10-rc6 2020-11-23 15:29:03 -08:00
i740_reg.h
i740fb.c fbdev: i740fb: use generic power management 2020-09-08 13:33:17 +02:00
imsttfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
imxfb.c video: fbdev: imxfb: ensure balanced regulator usage 2020-04-17 15:50:07 +02:00
Kconfig drm next for 5.10-rc1 2020-10-15 10:46:16 -07:00
leo.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
macfb.c video: fbdev: Replace HTTP links with HTTPS ones 2020-07-20 11:47:29 +02:00
macmodes.c
macmodes.h
Makefile drm next for 5.10-rc1 2020-10-15 10:46:16 -07:00
maxinefb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
metronomefb.c video: fbdev: Replace HTTP links with HTTPS ones 2020-07-20 11:47:29 +02:00
mx3fb.c fbdev: mx3fb: const pointer to ipu_di_signal_cfg 2020-04-12 22:09:35 +02:00
n411.c
neofb.c video: fbdev: neofb: fix memory leak in neo_scan_monitor() 2020-07-10 16:17:24 +02:00
ocfb.c video: ocfb: Use devm_platform_ioremap_resource() in ocfb_probe() 2020-01-03 14:27:49 +01:00
offb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
p9100.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
platinumfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
platinumfb.h
pm2fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
pm3fb.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
pmag-aa-fb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
pmag-ba-fb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
pmagb-b-fb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
ps3fb.c fbmem: pull fbcon_update_vcs() out of fb_set_var() 2020-08-04 07:37:23 +02:00
pvr2fb.c video: fbdev: pvr2fb: initialize variables 2020-08-05 19:47:22 +02:00
pxa3xx-gcu.c misc: cleanup minor number definitions in c file into miscdevice.h 2020-03-18 12:27:03 +01:00
pxa3xx-gcu.h
pxa168fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
pxa168fb.h
pxafb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
pxafb.h video: pxafb: Remove cpufreq policy notifier 2019-08-26 10:02:02 +02:00
q40fb.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
s1d13xxxfb.c fbdev: s1d13xxxfb: add missed unregister_framebuffer in remove 2020-04-17 15:50:12 +02:00
s3c2410fb-regs-lcd.h fbdev: s3c2410fb: remove mach header dependency 2020-08-20 17:48:12 +02:00
s3c2410fb.c fbdev: s3c2410fb: remove mach header dependency 2020-08-20 17:48:12 +02:00
s3c2410fb.h
s3c-fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
s3fb.c fbdev: s3fb: use generic power management 2020-09-08 13:33:19 +02:00
sa1100fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sa1100fb.h ARM/fbdev: sa11x0: Switch to use GPIO descriptors 2020-04-17 15:50:11 +02:00
sbuslib.c fbdev: sbuslib: integer overflow in sbusfb_ioctl_helper() 2018-10-08 12:57:36 +02:00
sbuslib.h
sh7760fb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
sh_mobile_lcdcfb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sh_mobile_lcdcfb.h fbdev/sh_mobile: remove sh_mobile_lcdc_display_notify 2019-06-12 20:28:11 +02:00
simplefb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
skeletonfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
sm501fb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sm712.h fbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display 2019-04-01 17:46:59 +02:00
sm712fb.c fbdev: sm712fb: handle ioremap() errors in probe 2020-09-08 13:33:02 +02:00
smscufx.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
ssd1307fb.c video: fbdev: ssd1307fb: Added support to Column offset 2020-09-08 13:33:03 +02:00
sstfb.c video: fbdev: sstfb: replace spurious snprintf() with sprintf() 2020-09-08 13:33:24 +02:00
sticore.h parisc/sticon: Add user font support 2020-10-15 08:12:59 +02:00
stifb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sunxvr500.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
sunxvr1000.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
sunxvr2500.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
tcx.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
tdfxfb.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
tgafb.c video: fbdev: tgafb: Avoid comma separated statements 2020-09-08 13:33:25 +02:00
tmiofb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
tridentfb.c drm pull for 5.6-rc1 2020-01-30 08:04:01 -08:00
udlfb.c video: fbdev: udlfb: fix kobj_to_dev.cocci warnings 2020-09-08 13:33:27 +02:00
uvesafb.c video: fbdev: uvesafb: fix "noblank" option handling 2020-06-21 09:58:55 +02:00
valkyriefb.c video: fbdev: valkyriefb.c: fix warning comparing pointer to 0 2020-05-06 21:04:45 +02:00
valkyriefb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
vesafb.c video: fbdev: vesafb: add missed release_region 2020-04-17 15:50:14 +02:00
vfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00
vga16fb.c Merge drm/drm-next into drm-misc-next 2020-09-14 18:11:40 +02:00
vt8500lcdfb.c video: vt8500lcdfb: fix fallthrough warning 2020-04-17 15:50:08 +02:00
vt8500lcdfb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
vt8623fb.c fbdev: vt8623fb: use generic power management 2020-09-08 13:33:18 +02:00
w100fb.c video: fbdev: w100fb: Fix a potential double free. 2020-05-06 20:22:25 +02:00
w100fb.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
wm8505fb_regs.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
wm8505fb.c video: fbdev: wm8505fb: fix sparse warnings about using incorrect types 2020-03-02 16:32:04 +01:00
wmt_ge_rops.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
wmt_ge_rops.h
xen-fbfront.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
xilinxfb.c video: constify fb ops across all drivers 2019-12-05 10:57:53 +02:00