[patch 2/4] x86: vdso: Remove bogus locking in update_vsyscall_tz()

[Thomas Gleixner <tglx@linutronix.de>]

[-- Attachment #1: x86-vdso-remove-bogus-locking-in-update_vsyscall_tz.patch --]
[-- Type: text/plain, Size: 946 bytes --]

Changing the sequence count in update_vsyscall_tz() is completely
pointless. 

The vdso code copies the data unprotected. There is no point to change
this as sys_tz is nowhere protected at all. See sys_gettimeofday().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/vsyscall_64.c |    5 -----
 1 file changed, 5 deletions(-)

Index: linux-2.6/arch/x86/kernel/vsyscall_64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/vsyscall_64.c
+++ linux-2.6/arch/x86/kernel/vsyscall_64.c
@@ -80,12 +80,7 @@ early_param("vsyscall", vsyscall_setup);
 
 void update_vsyscall_tz(void)
 {
-	unsigned long flags;
-
-	write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags);
-	/* sys_tz has changed */
 	vsyscall_gtod_data.sys_tz = sys_tz;
-	write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
 }
 
 void update_vsyscall(struct timespec *wall_time, struct timespec *wtm,