This is a note to let you know that I've just added the patch titled

    uprobes, x86: Fix _TIF_UPROBE vs _TIF_NOTIFY_RESUME

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     uprobes-x86-fix-_tif_uprobe-vs-_tif_notify_resume.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 82975bc6a6df743b9a01810fb32cb65d0ec5d60b Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <[email protected]>
Date: Fri, 21 Nov 2014 13:26:07 -0800
Subject: uprobes, x86: Fix _TIF_UPROBE vs _TIF_NOTIFY_RESUME

From: Andy Lutomirski <[email protected]>

commit 82975bc6a6df743b9a01810fb32cb65d0ec5d60b upstream.

x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns.  I suspect that this is a mistake and that
the code only works because int3 is paranoid.

Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug.  With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.

Reported-by: Oleg Nesterov <[email protected]>
Acked-by: Srikar Dronamraju <[email protected]>
Acked-by: Borislav Petkov <[email protected]>
Signed-off-by: Andy Lutomirski <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/x86/include/asm/thread_info.h |    2 +-
 kernel/events/uprobes.c            |    1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -147,7 +147,7 @@ struct thread_info {
 /* Only used for 64 bit */
 #define _TIF_DO_NOTIFY_MASK                                            \
        (_TIF_SIGPENDING | _TIF_MCE_NOTIFY | _TIF_NOTIFY_RESUME |       \
-        _TIF_USER_RETURN_NOTIFY)
+        _TIF_USER_RETURN_NOTIFY | _TIF_UPROBE)
 
 /* flags to check in __switch_to() */
 #define _TIF_WORK_CTXSW                                                        
\
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1511,7 +1511,6 @@ bool uprobe_deny_signal(void)
                if (__fatal_signal_pending(t) || 
arch_uprobe_xol_was_trapped(t)) {
                        utask->state = UTASK_SSTEP_TRAPPED;
                        set_tsk_thread_flag(t, TIF_UPROBE);
-                       set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
                }
        }
 


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/x86-mm-set-nx-across-entire-pmd-at-boot.patch
queue-3.10/uprobes-x86-fix-_tif_uprobe-vs-_tif_notify_resume.patch
queue-3.10/x86_64-traps-stop-using-ist-for-ss.patch
queue-3.10/x86_64-traps-fix-the-espfix64-df-fixup-and-rewrite-it-in-c.patch
queue-3.10/x86_64-traps-rework-bad_iret.patch
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