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[IA64] fix stack alignment for ia32 signal handlers

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This fixes the setup of the alignment of the signal frame, so that all
signal handlers are run with a properly aligned stack frame.

The current code "over-aligns" the stack pointer so that the stack frame
is effectively always mis-aligned by 4 bytes.  But what we really want
is that on function entry ((sp + 4) & 15) == 0, which matches what would
happen if the stack were aligned before a "call" instruction.

i386 and x86_64 are already fixed by d347f37227

Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit is contained in:
Markus F.X.J. Oberhumer 2007-04-23 12:00:05 +02:00 committed by Tony Luck
parent 0e17b56098
commit 66761522a7
1 changed files with 5 additions and 1 deletions
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6
arch/ia64/ia32/ia32_signal.c
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@ -811,7 +811,11 @@ get_sigframe (struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
}
/* Legacy stack switching not supported */
return (void __user *)((esp - frame_size) & -8ul);
esp -= frame_size;
/* Align the stack pointer according to the i386 ABI,
* i.e. so that on function entry ((sp + 4) & 15) == 0. */
esp = ((esp + 4) & -16ul) - 4;
return (void __user *) esp;
}
static int