Re: [hatari-devel] ASAN issues with tests

[Thomas Huth <th.huth@xxxxxxxxx>]

Am Fri, 29 Jul 2022 23:40:56 +0300
schrieb Eero Tamminen <oak@xxxxxxxxxxxxxx>:

> Hi,
> 
> On 29.7.2022 18.26, Eero Tamminen wrote:
> > It does not give error if VDI screen size is small enough.
> > 
> > And it does not happen with Videl code (used for Falcon & TT).  
> 
> Test tries to set screen to the end of emulated machine RAM.
> 
> I'm not able to reproduce ASAN error if I disable SMALL_MEM build 
> option, i.e. it's a SMALL_MEM config bug.
> 
> 
> > With "--vdi-planes 4", 640x200 is enough to trigger it, with 2 planes 
> > 640x400, and with mono, 640x736.  
> 
> All these cause screen area to be slightly larger
> than the 56 KB padding Thomas added in his SMALL_MEM workaround:
> https://git.tuxfamily.org/hatari/hatari.git/commit/?id=5316b4081e9d3fa177ed14419369bc13892af4e8
> 
> It appears that SMALL_MEM ST-RAM padding should take into account also 
> largest possible VDI screen size (300KB), i.e. use MAX_VDI_BYTES.

Theoretically, this should not be necessary. The 56k "runaway ramp" is only
there for the ST/STE screen mode rendering functions from screen.c. The
generic functions from screenConvert.c should contain proper checks a la:

		if (nLineEndAddr > STRamEnd)
		{
			Screen_memset_uint32(hvram_line, palette.native[0], pitch);
			hvram_line += pitch;
			continue;
		}

I wonder why they don't apply here. I'll try to have a look at this today.

 Thomas