lkml.org 
[lkml]   [2012]   [Aug]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 74/74] lto, workaround: Mark do_futex noinline to prevent clobbering ebp
On 08/22/2012 07:29 PM, Andi Kleen wrote:
> How about just use register arguments for the first three arguments.
> This should work for the syscalls at least (may be too risky for all
> other asm entry points)

Well, it's just an effort to convert each one in turn...

> And for syscalls with more than three generate a stub that saves on the stack
> explicitely. This could be done using the new fancy SYSCALL definition macros
> (except that arch/x86 would need to start using them too in its own code)

I don't think there is any point. Just push the six potential arguments
to the stack and be done with it.

> Or is there some subtle reason with syscall restart and updated args
> that prevents it?
>
> Perhaps newer gcc can do regparm(X), X > 3 too, may be worth trying.

No, there is no such ABI defined.

> Don't have time to look into this currently though.

Always the problem.

-hpa


--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.



\
 
 \ /
  Last update: 2012-08-23 05:41    [W:0.082 / U:1.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site