Re: [RFC 3/4] x86/signal/64: Re-add support for SS in the 64-bit signal context

Cyrill Gorcunov
2015-10-14T17:01:51Z

On Wed, Oct 14, 2015 at 07:57:02PM +0300, Stas Sergeev wrote:
...
> > correct? This should work for us. Stas, mind to refresh my memory,
> > which ss value doesmu setups here?
>
> Nothing.
> Older dosemus didn't care about touching __pad0, so
> whatever kernel saves there, is still there, even when
> dosemu needs another value.
> The problem starts to happen IIRC when dosemu invalidates
> the LDT entry that was previously saved by the kernel as an SS.
> IIRC this was causing the SIGSEGV right from sigreturn().
> It is actually a bit annoying to have such bad code in kernel
> only for the sake of the older dosemu.

I see. Thanks a huge for info!