Re: Linux doesn't follow x86/x86-64 ABI wrt direction flag

Michael Matz
2008-03-05T21:02:20Z

Hi,

On Wed, 5 Mar 2008, Jan Hubicka wrote:

> Kernels almost never follow ABI used by applications to last detail.

But we aren't talking about the ABI the kernel uses internally, but about
what is exposed to user-space via signal handlers. _That_ part needs to
be followed, and if it isn't it's a serious problem we somehow have to
hack around.

> Linux kernel is disabling red zone and use kernel code model, yet the
> ABI is not going to be adjusted for that.
>
> This is resonably easy to fix on kernel side in signal handling, or by
> removing std usage completely

That is true. But it requires updating the kernel to a fixed one if you
want to run your programs compiled by 4.3 :-/ Not something we'd like to
demand.

Ciao,
Michael.