Wow! So you found the culprit. >From Wednesday I will be on Christmas holidays, so I can help if needed
Ciao e buona giornata. "GP! In mezzo al campo stai proprio schifoso!" Coach M.Russo Il lun 22 dic 2025, 11:00 Helge Deller <[email protected]> ha scritto: > * William Burrow <[email protected]>: > > Hello, Camaleón and Salvatore. > > I have a similar problem with the TTYs and am very glad to have found > > this message. Hopefully, my reply can make it to the list. > > . > > The offending commit was fairly easy to find as will be detailed > > later. The git bisect on the linux-stable repo found the following > > commit as the problem: > > . > > ------------ First commit to cause the problem ------------ > > commit 0998a6cb232674408a03e8561dc15aa266b2f53b > > Author: Junjie Cao <[email protected]> > > Date: Mon Oct 20 21:47:01 2025 +0800 > > > > fbdev: bitblit: bound-check glyph index in bit_putcs* > > > > commit 18c4ef4e765a798b47980555ed665d78b71aeadf upstream. > > ------------ First commit to cause the problem ------------ > > . > > I leave it as an exercise to the reader to solve the problem created > > by this commit. Hopefully, soon. > > Can someone please try attached patch? > Alternatively (if then another char that the "copyright symbol" is > visible), we could try replacing it by: > ch = 0x20; /* use ASCII space character */ > > Overall, I'm still puzzled if the original patch is correct. > I always thought fonts have 256 or 512 characters, which means the > original patch isn't necessary at all. > > Helge > > > >From 65c6bb3e7d06dba09f6b529a2478ee818c14e6ef Mon Sep 17 00:00:00 2001 > From: Helge Deller <[email protected]> > Date: Mon, 22 Dec 2025 10:19:55 +0100 > Subject: [PATCH] fbdev: bitblit: fix bound-check of glyph index in > bit_putcs* > > The patch 18c4ef4e765a ("fbdev: bitblit: bound-check glyph index in > bit_putcs*") seems to trigger problems on virtual consoles, which > suddently show up with lots of copyright symbols. This is e.g. reported > here: > > https://www.reddit.com/r/debian/comments/1pnrm5t/problem_with_virtual_consoles_covered_with_a/ > > Try to narrow the issue down. Here we use the "last" char of a given > font (instead of char #0), if the previous char exceeds the actual > font's glyph count. > > Reported-by: Gianluca Renzi <[email protected]> > Signed-off-by: Helge Deller <[email protected]> > Fixes: 18c4ef4e765a ("fbdev: bitblit: bound-check glyph index in > bit_putcs*") > > diff --git a/drivers/video/fbdev/core/bitblit.c > b/drivers/video/fbdev/core/bitblit.c > index 085ffb44c51a..6b2f9748cd78 100644 > --- a/drivers/video/fbdev/core/bitblit.c > +++ b/drivers/video/fbdev/core/bitblit.c > @@ -87,7 +87,7 @@ static inline void bit_putcs_aligned(struct vc_data *vc, > struct fb_info *info, > u16 ch = scr_readw(s++) & charmask; > > if (ch >= charcnt) > - ch = 0; > + ch = (charcnt - 1); > src = vc->vc_font.data + (unsigned int)ch * cellsize; > > if (attr) { > @@ -126,7 +126,7 @@ static inline void bit_putcs_unaligned(struct vc_data > *vc, > u16 ch = scr_readw(s++) & charmask; > > if (ch >= charcnt) > - ch = 0; > + ch = (charcnt - 1); > src = vc->vc_font.data + (unsigned int)ch * cellsize; > > if (attr) { > >
