[PATCH RT 07/25][RFC 3.0.23-rt39-rc1] x86: vdso: Remove bogus locking in update_vsyscall_tz()

[Steven Rostedt]

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

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@xxxxxxxxxxxxx>
Cc: stable-rt@xxxxxxxxxxxxxxx
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
 arch/x86/kernel/vsyscall_64.c |    5 -----
 1 files changed, 0 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c
index 0a7dc13..c378a18 100644
--- a/arch/x86/kernel/vsyscall_64.c
+++ b/arch/x86/kernel/vsyscall_64.c
@@ -58,12 +58,7 @@ DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data) =
 
 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,
-- 
1.7.8.3


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/