On Sun, Mar 26, 2017 at 11:37:21AM +1100, Jonathan Gray wrote:
> On Sat, Mar 25, 2017 at 06:51:32PM +0100, Hiltjo Posthuma wrote:
> > On Sat, Mar 25, 2017 at 05:43:27PM +0200, Giannis Tsaraias wrote:
> > > On Sat, Mar 25, 2017 at 03:24:26PM +0100, Benjamin Baier wrote:
> > > > Patch to add wxneeded to dosbox. I got a application that otherwise
> > > > crashes with the following dosbox error message.
> > > >
> > > > >Setting excute permission on the code cache has failed
> > > > >Exit to error: DRC64:Unhandled memory reference
> > > >
> > >
> > > I saw the W^X violation too and had to do this, but forgot to send the
> > > diff.
> > > FWIW, OK tsg@ if someone wants to commit.
> > >
> >
> > Hey,
> >
> > I noticed it too while playing Mortal Kombat 1 :)
> >
> > Some other games (skiordi, stunts) don't crash.
>
> Instead of blindly setting USE_WXNEEDED, I'd prefer if someone who has
> a case that triggers this can try disabling the various cpu core options
> in configure.
Hey,
I think the issue is with the CPU core=dynamic. It uses a cache and sets
PROT_WRITE|PROT_EXEC on a region.
The log message is found in the files:
./src/cpu/core_dynrec/cache.h:
LOG_MSG("Setting excute permission on the code cache has failed");
./src/cpu/core_dyn_x86/cache.h:
LOG_MSG("Setting excute permission on the code cache has failed!");
and the code:
if(mprotect(cache_code_link_blocks,CACHE_TOTAL+CACHE_MAXSIZE+PAGESIZE_TEMP,PROT_WRITE|PROT_READ|PROT_EXEC))
Log_MSG("Setting excute permission on the code cache has
failed!");
To workaround this, but without requiring WXNEEDED:
Change in the dosbox config:
[cpu]
core=dynamic
cycles=auto
to:
[cpu]
core=normal
cycles=10000
I don't have the knowledge to patch core=dynamic, but hopefully this
information helps in some way.
--
Kind regards,
Hiltjo
