odd utrace testing results on s390x

[Oleg Nesterov]

On 12/22, caiqian at redhat.com wrote:
>
> The following are testing results on s390x kernels build from the source,
>
> http://kojipkgs.fedoraproject.org/packages/kernel/2.6.32.2/14.fc13/src/kernel-2.6.32.2-14.fc13.src.rpm
>
> without and with CONFIG_UTRACE using the latest ptrace-utrace git tree.
>
> ptrace testsuite: looks like step-simple is starting to fail,

Damn, my fault. I forgot to cc you when I sent the fix for s390 (attached
below), and I forgot to remind you about this fix when we discussed the
testing on s390.

Could you please re-test with this patch applied?

> and a different syscall number when syscall-from-clone failed.

This is not clear to me, will take a look.

Thanks!

Oleg.

-----------------------------------------------------------------------------
Untested, but hopefully trivial enough and should't change the
compiled code.

Nobody except ptrace itself should use task->ptrace or PT_PTRACED
directly, change arch/s390/kernel/traps.c to use the helper.

Signed-off-by: Oleg Nesterov <oleg at redhat.com>
Acked-by: Roland McGrath <roland at redhat.com>
---

 arch/s390/kernel/traps.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- V1/arch/s390/kernel/traps.c~S390_DONT_ABUSE_PT_PTRACED	2009-04-06 00:03:36.000000000 +0200
+++ V1/arch/s390/kernel/traps.c	2009-12-09 20:31:49.000000000 +0100
@@ -18,7 +18,7 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/errno.h>
-#include <linux/ptrace.h>
+#include <linux/tracehook.h>
 #include <linux/timer.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
@@ -382,7 +382,7 @@ void __kprobes do_single_step(struct pt_
 					SIGTRAP) == NOTIFY_STOP){
 		return;
 	}
-	if ((current->ptrace & PT_PTRACED) != 0)
+	if (tracehook_consider_fatal_signal(current, SIGTRAP))
 		force_sig(SIGTRAP, current);
 }
 
@@ -483,7 +483,7 @@ static void illegal_op(struct pt_regs * 
 		if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
 			return;
 		if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
-			if (current->ptrace & PT_PTRACED)
+			if (tracehook_consider_fatal_signal(current, SIGTRAP))
 				force_sig(SIGTRAP, current);
 			else
 				signal = SIGILL;