Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly forked tasks

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From	Josh Poimboeuf <jpoimboe@redhat.com>
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Subject	Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly forked tasks
Date	Wed, 21 Sep 2016 13:40:02 +0200
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On Tue, Sep 20, 2016 at 11:39:35PM -0700, Andy Lutomirski wrote:
> > 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.
> >                  */
> >         GLOBAL_ENTRY(ia64_invoke_schedule_tail)
> >                 ...
> 
> That comment has to be wrong.  What syscall could possibly be
> restarted across schedule_tail()?  It's a brand new thread and has
> literally never done a syscall.

Hm, yeah, that comment doesn't make any sense.

> There may be another reason that the registers are live there, but I
> generally do my best to never look at ia64 asm code.

Yeah, I'm just going to turn around, pretend I never saw it, and slowly
walk away...

-- 
Josh

Thread

[PATCH 0/9] x86/entry/head: standardize the end of the stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 2/9] x86/entry/32: rename 'error_code' to 'common_exception' Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 6/9] x86/asm/head: use a common function for starting CPUs Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 3/9] x86/entry/32: fix the end of the stack for newly forked tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
    Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly  forked tasks Brian Gerst <brgerst@gmail.com> - 2016-09-21 03:20 +0200
      Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly  forked tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-21 05:30 +0200
        Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly  forked tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-21 05:40 +0200
        Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly  forked tasks Andy Lutomirski <luto@amacapital.net> - 2016-09-21 08:50 +0200
          Re: [PATCH 3/9] x86/entry/32: fix the end of the stack for newly  forked tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-21 13:40 +0200
  [PATCH 9/9] x86: move _stext marker to before head code Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 7/9] x86/head: put real return address on idle task stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 4/9] x86/head/32: fix the end of the stack for idle tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 5/9] x86/smp: fix initial idle stack location on 32-bit Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
  [PATCH 1/9] x86/entry/head/32: use local labels Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200
    Re: [PATCH 1/9] x86/entry/head/32: use local labels Andy Lutomirski <luto@amacapital.net> - 2016-09-21 03:00 +0200
      Re: [PATCH 1/9] x86/entry/head/32: use local labels Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-21 05:00 +0200
  [PATCH 8/9] x86/head: fix the end of the stack for idle tasks Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-20 22:10 +0200

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