[PATCH] x86-64: Support -mregparm arguments for signals with SA_SIGINFO in compat mode

The recent change to make x86_64 support i386 binaries compiled
with -mregparm=3 only covered signal handlers without SA_SIGINFO.
(the 3-arg "real-time" ones)

To be compatible with i386, both types should be supported.

Signed-off-by: Albert Cahalan <acahalan@gmail.com>
Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86_64/ia32/ia32_signal.c b/arch/x86_64/ia32/ia32_signal.c
index 0e0a266d976f..ff499ef2a1ba 100644
--- a/arch/x86_64/ia32/ia32_signal.c
+++ b/arch/x86_64/ia32/ia32_signal.c
@@ -584,6 +584,11 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         regs->rdx = (unsigned long) &frame->info;
         regs->rcx = (unsigned long) &frame->uc;
 
+        /* Make -mregparm=3 work */
+        regs->rax = sig;
+        regs->rdx = (unsigned long) &frame->info;
+        regs->rcx = (unsigned long) &frame->uc;
+
         asm volatile("movl %0,%%ds" :: "r" (__USER32_DS)); 
         asm volatile("movl %0,%%es" :: "r" (__USER32_DS));