Re: SMP Sparc64 : bug in clone?

[Erik de Castro Lopo <nospam@mega-nerd.com>]

On Mon, 29 Apr 2002 13:14:31 -0700 (PDT)
"David S. Miller" <davem@redhat.com> wrote:

> 
> You need to subtract 2047 (the Sparc64 "stack bias") to the stack you
> pass to clone.

I've just got around to playing with this.

Should I be subtract 2047 bytes (unlikely) or 2047 * sizeof (void*) bytes?

The stack is defined as:

#define  STACK_SIZE (1<<15)

static void* stack [STACK_SIZE] ;

And I've tried pass the following pointers to clone ():

	&stack [STACK_SIZE]
	&stack [STACK_SIZE-2047]
	&stack [STACK_SIZE-2048]
	&stack [STACK_SIZE/2]
	((char*) (&stack [STACK_SIZE])) - 2047
	((char*) (&stack [STACK_SIZE])) - 2048

None of the above works without the CLONE_VM flag. The first four do work
with it.

Any further clues?

Erik
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  Erik de Castro Lopo  nospam@mega-nerd.com (Yes it's valid)
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