Commit f326d22b authored by john stultz's avatar john stultz Committed by Linus Torvalds
Browse files

[PATCH] ppc32: stop misusing NTP's time_offset value 



As part of my timeofday rework, I've been looking at the NTP code and I
noticed that the PPC architecture is apparently misusing the NTP's
time_offset (it is a terrible name!) value as some form of timezone offset.

This could cause problems when time_offset changed by the NTP code.  This
patch changes the PPC code so it uses a more clear local variable:
timezone_offset.

Signed-off-by: default avatarJohn Stultz <johnstul@us.ibm.com>
Acked-by: default avatarTom Rini <trini@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent e6b6239f

arch/ppc/kernel/time.c

+8 −5
Original line number Diff line number Diff line
@@ -89,6 +89,9 @@ unsigned long tb_to_ns_scale; 


extern unsigned long wall_jiffies;



/* used for timezone offset */

static long timezone_offset;



DEFINE_SPINLOCK(rtc_lock);



EXPORT_SYMBOL(rtc_lock);
@@ -170,7 +173,7 @@ void timer_interrupt(struct pt_regs * regs) 
		     xtime.tv_sec - last_rtc_update >= 659 &&

		     abs((xtime.tv_nsec / 1000) - (1000000-1000000/HZ)) < 500000/HZ &&

		     jiffies - wall_jiffies == 1) {

		  	if (ppc_md.set_rtc_time(xtime.tv_sec+1 + time_offset) == 0)

		  	if (ppc_md.set_rtc_time(xtime.tv_sec+1 + timezone_offset) == 0)

				last_rtc_update = xtime.tv_sec+1;

			else

				/* Try again one minute later */
@@ -286,7 +289,7 @@ void __init time_init(void) 
	unsigned old_stamp, stamp, elapsed;



        if (ppc_md.time_init != NULL)

                time_offset = ppc_md.time_init();

                timezone_offset = ppc_md.time_init();



	if (__USE_RTC()) {

		/* 601 processor: dec counts down by 128 every 128ns */
@@ -331,10 +334,10 @@ void __init time_init(void) 
	set_dec(tb_ticks_per_jiffy);



	/* If platform provided a timezone (pmac), we correct the time */

        if (time_offset) {

		sys_tz.tz_minuteswest = -time_offset / 60;

        if (timezone_offset) {

		sys_tz.tz_minuteswest = -timezone_offset / 60;

		sys_tz.tz_dsttime = 0;

		xtime.tv_sec -= time_offset;

		xtime.tv_sec -= timezone_offset;

        }

        set_normalized_timespec(&wall_to_monotonic,

                                -xtime.tv_sec, -xtime.tv_nsec);

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