Hello,

the attached patch fixes two asm snippets in the S/390 code. Although
in the 64 bit directory the 32 bit add instruction is used to subtract
from the stack pointer in r15. This is wrong an leads to especially
nasty bugs whenever crossing a 4GB boundary with the stack pointer.

Please apply if you think it is ok.

Bye,

-Andreas-


2008-09-22 Deborah S. Townsend <dstownse@us.ibm.com>

* sysdeps/s390/s390-64/s390x-mcount.S: Replace ahi with aghi.
* sysdeps/unix/sysv/linux/s390/s390-64/socket.S: Likewise.


Index: sysdeps/s390/s390-64/s390x-mcount.S
===================================================================
--- sysdeps/s390/s390-64/s390x-mcount.S.orig 2005-05-26 16:30:45.000000000 +0200
+++ sysdeps/s390/s390-64/s390x-mcount.S 2008-09-22 14:54:23.000000000 +0200
@@ -64,7 +64,7 @@ C_LABEL(_mcount)
/* Pop the saved registers. Please note that `mcount' has no
return value. */
lmg %r14,%r5,160(%r15)
- ahi %r15,224
+ aghi %r15,224
br %r14
ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(_mcount))

Index: sysdeps/unix/sysv/linux/s390/s390-64/socket.S
===================================================================
--- sysdeps/unix/sysv/linux/s390/s390-64/socket.S.orig 2005-12-20 07:55:02.000000000 +0100
+++ sysdeps/unix/sysv/linux/s390/s390-64/socket.S 2008-09-22 14:55:53.000000000 +0200
@@ -61,7 +61,7 @@ ENTRY(__socket)
cfi_offset (%r6,-112)
lgr %r1,%r15
lg %r0,8(%r15) /* Load eos. */
- ahi %r15,-208 /* Buy stack space. */
+ aghi %r15,-208 /* Buy stack space. */
cfi_adjust_cfa_offset (208)
stg %r1,0(%r15) /* Store back chain. */
stg %r0,8(%r15) /* Store eos. */

On Mon, 2008-09-22 at 15:15 +0200, Andreas Krebbel wrote:
> the attached patch fixes two asm snippets in the S/390 code. Although
> in the 64 bit directory the 32 bit add instruction is used to subtract
> from the stack pointer in r15. This is wrong an leads to especially
> nasty bugs whenever crossing a 4GB boundary with the stack pointer.

That is a nasty one!

> Please apply if you think it is ok.

The fix is correct.

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.