Re: [PATCH] sys_poll(): fix function definition/negative timeoutvalues

[Eric Dumazet]

Le jeudi 15 septembre 2011 Ã 20:12 +0200, Andi Kleen a Ãcrit :
> On Thu, Sep 15, 2011 at 08:05:17PM +0200, Eric Dumazet wrote:
> > Le jeudi 15 septembre 2011 Ã 10:47 -0700, Andi Kleen a Ãcrit :
> > > Thomas Meyer <thomas@xxxxxxxx> writes:
> > > 
> > > > Fix negative timeout values for x86 userland on x86_64 kernels.
> > > > Align sys_poll() definition to glibc's definition.
> > > 
> > > Nack. Please write a compat wrapper that sign extends.
> > > 
> > 
> > Why ?
> 
> Because we shouldn't change existing interfaces and there could
> be valid reasons on 64bit for really long delays.

I disagree.

Existing interface and POSIX mandates "int delay"

The kernel part of the contract was fine when we supported 32bit only
machines, by chance, because sizeof(int) == sizeof(long).

If you want more than 31 bits delay, then we need a new interface, and
this new interface must also work on 32bit arches (sort of poll64())




--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/