On Fri, Dec 16, 2016 at 03:17:35PM +0100, Petr Mladek wrote:

On Thu 2016-12-08 12:08:27, Josh Poimboeuf wrote:

quoted

The _TIF_ALLWORK_MASK macro automatically includes the least-significant
16 bits of the thread_info flags, which is less than obvious and tends
to create confusion and surprises when reading or modifying the code.

Define the flags explicitly.

Signed-off-by: Josh Poimboeuf <redacted>
---
 arch/x86/include/asm/thread_info.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index ad6f5eb0..1fe6043 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h

@@ -73,9 +73,6 @@ struct thread_info {
  * thread information flags
  * - these are process state flags that various assembly files
  *   may need to access
- * - pending work-to-be-done flags are in LSW

Yup, this is not true because also some flags from the most
significant bits are in the _TIF_ALLWORK_MASK.

quoted

- * - other flags in MSW
- * Warning: layout of LSW is hardcoded in entry.S
  */
 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */

@@ -133,8 +130,10 @@ struct thread_info {
 
 /* work to do on any return to user space */
 #define _TIF_ALLWORK_MASK						\
-	((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_TRACEPOINT |	\
-	_TIF_NOHZ)
+	(_TIF_SYSCALL_TRACE | _TIF_NOTIFY_RESUME | _TIF_SIGPENDING |	\
+	 _TIF_SINGLESTEP | _TIF_NEED_RESCHED | _TIF_SYSCALL_EMU |	\
+	 _TIF_SYSCALL_AUDIT | _TIF_USER_RETURN_NOTIFY | _TIF_UPROBE |	\
+	 _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ)

All flags are sorted by the number except for
_TIF_SINGLESTEP and _TIF_NEED_RESCHED  ;-)

You're right, I'll swap them :-)

The patch does not change the existing behavior. The same
existing flags are listed.

Reviewed-by: Petr Mladek <pmladek@suse.com>

Best Regards,
Petr

-- 
Josh