diff mbox series

[v2] mips: fix abort on integer overflow

Message ID 3ef979a8-3ee1-eb2d-71f7-d788ff88dd11@redhat.com
State New
Headers show
Series [v2] mips: fix abort on integer overflow | expand

Commit Message

Mikulas Patocka Sept. 28, 2023, 7:55 p.m. UTC 
On Thu, 28 Sep 2023, Richard Henderson wrote:

> Just call force_sig_fault directly.
> 
> 
> r~

OK. Here I'm resending it.

Mikulas



From: Mikulas Patocka <mpatocka@redhat.com>

Qemu mips userspace emulation crashes with "qemu: unhandled CPU exception 
0x15 - aborting" when one of the integer arithmetic instructions detects 
an overflow.

This patch fixes it so that it delivers SIGFPE with FPE_INTOVF instead.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: qemu-stable@nongnu.org

---
 linux-user/mips/cpu_loop.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Richard Henderson Oct. 3, 2023, 8:28 p.m. UTC | #1 
On 9/28/23 12:55, Mikulas Patocka wrote:
> 
> 
> On Thu, 28 Sep 2023, Richard Henderson wrote:
> 
>> Just call force_sig_fault directly.
>>
>>
>> r~
> 
> OK. Here I'm resending it.
> 
> Mikulas
> 
> 
> 
> From: Mikulas Patocka <mpatocka@redhat.com>
> 
> Qemu mips userspace emulation crashes with "qemu: unhandled CPU exception
> 0x15 - aborting" when one of the integer arithmetic instructions detects
> an overflow.
> 
> This patch fixes it so that it delivers SIGFPE with FPE_INTOVF instead.
> 
> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
> Cc: qemu-stable@nongnu.org

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

and queued to linux-user-next.


r~
diff mbox series

Patch

Index: qemu/linux-user/mips/cpu_loop.c
===================================================================
--- qemu.orig/linux-user/mips/cpu_loop.c
+++ qemu/linux-user/mips/cpu_loop.c
@@ -180,7 +180,9 @@  done_syscall:
             }
             force_sig_fault(TARGET_SIGFPE, si_code, env->active_tc.PC);
             break;
-
+	case EXCP_OVERFLOW:
+            force_sig_fault(TARGET_SIGFPE, TARGET_FPE_INTOVF, env->active_tc.PC);
+            break;
         /* The code below was inspired by the MIPS Linux kernel trap
          * handling code in arch/mips/kernel/traps.c.
          */