On Tue, Sep 20, 2016 at 10:25:16PM -0500, Josh Poimboeuf wrote:
> On Tue, Sep 20, 2016 at 09:10:55PM -0400, Brian Gerst wrote:
> > Dropping asmlinkage from schedule_tail() would be a better option if
> > possible.
> My understanding is that it's still needed for ia64. AFAICT, ia64
> relies on schedule_tail() having the syscall_linkage function attribute.
> From the gcc manual:
> This attribute is used to modify the IA64 calling convention by
> marking all input registers as live at all function exits. This makes
> it possible to restart a system call after an interrupt without having
> to save/restore the input registers. This also prevents kernel data
> from leaking into application code.
> And the ia64 entry code has some similar language:
> * Invoke schedule_tail(task) while preserving in0-in7, which
> may be needed
> * in case a system call gets restarted.
(But I should note that I'm a complete ia64 neophyte, so I could be