Patch "x86/asm/entry/64: Remove pointless jump to irq_return" has been added to the 4.1-stable tree

Patch "x86/asm/entry/64: Remove pointless jump to irq_return" has been added to the 4.1-stable tree

[gregkh]

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

    x86/asm/entry/64: Remove pointless jump to irq_return

to the 4.1-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:
     x86-asm-entry-64-remove-pointless-jump-to-irq_return.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5ca6f70f387b4f82903037cc3c5488e2c97dcdbc Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@kernel.org>
Date: Thu, 4 Jun 2015 13:24:29 -0700
Subject: x86/asm/entry/64: Remove pointless jump to irq_return

From: Andy Lutomirski <luto@kernel.org>

commit 5ca6f70f387b4f82903037cc3c5488e2c97dcdbc upstream.

INTERRUPT_RETURN turns into a jmp instruction.  There's no need
for extra indirection.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2f2318653dbad284a59311f13f08cea71298fd7c.1433449436.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/kernel/entry_64.S |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -793,8 +793,6 @@ retint_kernel:
 restore_c_regs_and_iret:
 	RESTORE_C_REGS
 	REMOVE_PT_GPREGS_FROM_STACK 8
-
-irq_return:
 	INTERRUPT_RETURN
 
 ENTRY(native_iret)
@@ -1640,7 +1638,7 @@ nmi_restore:
 
 	/* Clear the NMI executing stack variable */
 	movq $0, 5*8(%rsp)
-	jmp irq_return
+	INTERRUPT_RETURN
 	CFI_ENDPROC
 END(nmi)
 


Patches currently in stable-queue which might be from luto@kernel.org are

queue-4.1/x86-nmi-enable-nested-do_nmi-handling-for-64-bit-kernels.patch
queue-4.1/x86-nmi-64-switch-stacks-on-userspace-nmi-entry.patch
queue-4.1/x86-nmi-64-remove-asm-code-that-saves-cr2.patch
queue-4.1/x86-nmi-64-use-df-to-avoid-userspace-rsp-confusing-nested-nmi-detection.patch
queue-4.1/x86-asm-entry-64-remove-pointless-jump-to-irq_return.patch
queue-4.1/x86-nmi-64-reorder-nested-nmi-checks.patch
queue-4.1/x86-nmi-64-improve-nested-nmi-comments.patch