On Sun, Jun 26, 2022 at 01:56:18AM +0200, Helge Deller wrote: > On 6/26/22 01:12, Helge Deller wrote: > > On 6/26/22 00:37, Daniel Vetter wrote: > >> On Sun, Jun 26, 2022 at 12:33:53AM +0200, Daniel Vetter wrote: > >>> On Sun, Jun 26, 2022 at 12:06:29AM +0200, Helge Deller wrote: > >>>> Enhance the check in the FBIOPUT_VSCREENINFO ioctl handler to verify if the > >>>> user-provided new screen size is bigger than the current font size. > >>>> > >>>> Signed-off-by: Helge Deller <deller@xxxxxx> > >>>> Cc: stable@xxxxxxxxxxxxxxx # v5.4+ > >>> > >>> Please squash with previous patch. You might also want to add a note there > >>> that on older kernels backporters need to open-code > >>> fbcon_info_from_console instead, since it only exists since > >>> 409d6c95f9c6 ("fbcon: Introduce wrapper for console->fb_info lookup") > >> > >> Maybe easier would be to include that patch in the backports instead of > >> open coding. > > > > I was afraid that WARN_CONSOLE_UNLOCKED() hadn't been backported. > > But it seems it's in v4.19+ (from patch 56e6c104e4f15), so that's ok. > > > > So, yes, it seems pushing 409d6c95f9c6 backwards is probably best. > > It would be the best solution, but sadly 409d6c95f9c6 can't easily be backported. > So, probably my other approach (fix up afterwards with extra patch) is > the way to go. Ah right there's some conflicts with the restoration/removal of scroll accel. > What's your thought on this ? I guess just open code in a separate backport is simplest. -Daniel > > Helge > > > > > Will try that approach now. > > > > Helge > > > > I think that's what Greg generally prefers at least, less > >> divergence between stable kernels. > >> -Daniel > >> > >>> > >>> With these two nits: Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> > >>> > >>>> --- > >>>> drivers/video/fbdev/core/fbmem.c | 4 +++- > >>>> 1 file changed, 3 insertions(+), 1 deletion(-) > >>>> > >>>> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c > >>>> index afa2863670f3..160389365a36 100644 > >>>> --- a/drivers/video/fbdev/core/fbmem.c > >>>> +++ b/drivers/video/fbdev/core/fbmem.c > >>>> @@ -1106,7 +1106,9 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, > >>>> return -EFAULT; > >>>> console_lock(); > >>>> lock_fb_info(info); > >>>> - ret = fb_set_var(info, &var); > >>>> + ret = fbcon_modechange_possible(info, &var); > >>>> + if (!ret) > >>>> + ret = fb_set_var(info, &var); > >>>> if (!ret) > >>>> fbcon_update_vcs(info, var.activate & FB_ACTIVATE_ALL); > >>>> unlock_fb_info(info); > >>>> -- > >>>> 2.35.3 > >>>> > >>> > >>> -- > >>> Daniel Vetter > >>> Software Engineer, Intel Corporation > >>> http://blog.ffwll.ch > >> > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch