From: Andy Lutomirski <luto@kernel.org>
Date: Tue, 6 Oct 2015 00:47:54 +0000 (-0700)
Subject: x86/entry, locking/lockdep: Move lockdep_sys_exit() to prepare_exit_to_usermode()
X-Git-Tag: firefly_0821_release~176^2~828^2~36
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=72f924783b8a87e4454516520ffb5f35e4930371;p=firefly-linux-kernel-4.4.55.git

x86/entry, locking/lockdep: Move lockdep_sys_exit() to prepare_exit_to_usermode()

Rather than worrying about exactly where LOCKDEP_SYS_EXIT should
go in the asm code, add it to prepare_exit_from_usermode() and
remove all of the asm calls that are followed by
prepare_exit_to_usermode().

LOCKDEP_SYS_EXIT now appears only in the syscall fast paths.

Signed-off-by: Andy Lutomirski <luto@kernel.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>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1736ebe948b845e68120b86b89091f3ec27f5e8e.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---

diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 80dcc9261ca3..d94a60c16029 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -220,6 +220,8 @@ __visible void prepare_exit_to_usermode(struct pt_regs *regs)
 	if (WARN_ON(!irqs_disabled()))
 		local_irq_disable();
 
+	lockdep_sys_exit();
+
 	/*
 	 * In order to return to user mode, we need to have IRQs off with
 	 * none of _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_USER_RETURN_NOTIFY,
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index b2909bf8cf70..a08ded481aba 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -255,7 +255,6 @@ ret_from_intr:
 	jb	resume_kernel			# not returning to v8086 or userspace
 
 ENTRY(resume_userspace)
-	LOCKDEP_SYS_EXIT
 	DISABLE_INTERRUPTS(CLBR_ANY)
 	TRACE_IRQS_OFF
 	movl	%esp, %eax
@@ -372,7 +371,6 @@ syscall_call:
 syscall_after_call:
 	movl	%eax, PT_EAX(%esp)		# store the return value
 syscall_exit:
-	LOCKDEP_SYS_EXIT
 	jmp	syscall_exit_work
 
 restore_all:
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 055a01de7c8d..7dc285036b6d 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -557,7 +557,6 @@ ret_from_intr:
 	jz	retint_kernel
 
 	/* Interrupt came from user space */
-	LOCKDEP_SYS_EXIT_IRQ
 GLOBAL(retint_user)
 	mov	%rsp,%rdi
 	call	prepare_exit_to_usermode