Re: [PATCH 1/5] signal(x86_32): Improve the signal stack overflow check

[Ingo Molnar <mingo@elte.hu>]

* Roland McGrath <roland@redhat.com> wrote:

> > I spent some time read you mail carefully and dig into the code again.
> > 
> > And yes, you are right. It's possible that SA_ONSTACK has been cleared
> > before the second signal on the same stack comes.
> 
> It's not necessary for SA_ONSTACK to have "been cleared", by which I 
> assume you mean a sigaction call with SA_ONSTACK not set in sa_flags.  
> That is indeed possible, but it's not the only case your patch broke.  
> It can just be a different signal whose sigaction never had 
> SA_ONSTACK, when you are still on the signal stack from an earlier 
> signal that did have SA_ONSTACK.
> 
> > So this patch is wrong :( . I will revise the other 4 patches.
> 
> For 2 and 3, I would rather just wait until we unify signal.c anyway.

ok, i've removed these patches from x86.git#testing for now:

 Subject: x86: improve the signal stack overflow logic, 32-bit
 Subject: x86: add a signal stack overflow check, 64-bit
 Subject: x86: add signal stack overflow check, 32-bit

and will wait for a resubmission and an Ack from Roland.

	Ingo