From: Markus F.X.J. Oberhumer Date: Mon, 23 Apr 2007 10:00:05 +0000 (+0200) Subject: [IA64] fix stack alignment for ia32 signal handlers X-Git-Tag: v2.6.22-rc1~141^2~6 X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=66761522a7bca951c1214498b80260533957e3ad;p=linux-2.6-omap-h63xx.git [IA64] fix stack alignment for ia32 signal handlers 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 d347f372273c2b3d86a66e2e1c94c790c208e166 Signed-off-by: Markus F.X.J. Oberhumer Signed-off-by: Tony Luck --- diff --git a/arch/ia64/ia32/ia32_signal.c b/arch/ia64/ia32/ia32_signal.c index b3355a9ca2c..7b38b73e782 100644 --- a/arch/ia64/ia32/ia32_signal.c +++ b/arch/ia64/ia32/ia32_signal.c @@ -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