Re: [Linux-ia64] small but important fix for clone2()

[David Mosberger <davidm@hpl.hp.com>]

Thursday's patch isn't sufficient.  It breaks threaded ia32 apps.  The
patch below should be complete, but more testing needs to be done.  At
least the x86 version of OpenOffice works again.

	--david

--- arch/ia64/kernel/entry.S~	Thu Jan 24 17:16:06 2002
+++ arch/ia64/kernel/entry.S	Sat Feb  9 10:41:59 2002
@@ -115,7 +115,7 @@
 	mov loc1=r16				// save ar.pfs across do_fork
 	.body
 	mov out1=in1
-	mov out3=0
+	mov out3\x16				// stacksize (compensates for 16-byte scratch area)
 	adds out2=IA64_SWITCH_STACK_SIZE+16,sp	// out2 = &regs
 	mov out0=in0				// out0 = clone_flags
 	br.call.sptk.many rp=do_fork
--- arch/ia64/ia32/ia32_entry.S~	Mon Nov 19 20:04:55 2001
+++ arch/ia64/ia32/ia32_entry.S	Sat Feb  9 10:41:41 2002
@@ -37,7 +37,7 @@
 	mov loc1=r16				// save ar.pfs across do_fork
 	.body
 	zxt4 out1=in1				// newsp
-	mov out3=0				// stacksize
+	mov out3\x16				// stacksize (compensates for 16-byte scratch area)
 	adds out2=IA64_SWITCH_STACK_SIZE+16,sp	// out2 = &regs
 	zxt4 out0=in0				// out0 = clone_flags
 	br.call.sptk.many rp=do_fork
--- arch/ia64/kernel/process.c~	Mon Feb  4 22:38:51 2002
+++ arch/ia64/kernel/process.c	Wed Feb  6 21:05:25 2002
@@ -267,7 +267,7 @@
 
 	if (user_mode(child_ptregs)) {
 		if (user_stack_base) {
-			child_ptregs->r12 = user_stack_base + user_stack_size;
+			child_ptregs->r12 = user_stack_base + user_stack_size - 16;
 			child_ptregs->ar_bspstore = user_stack_base;
 			child_ptregs->ar_rnat = 0;
 			child_ptregs->loadrs = 0;