[PATCH] time: sched_clock: fix integer overflow

[Baruch Siach]

The expression '(1 << 32)' happens to evaluate as 0 on ARM, but it evaluates as
1 on xtensa and x86_64. This zeros sched_clock_mask, and breaks sched_clock().
Set the type of 1 to 'unsigned long long' to get the value we need.

Reported-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
Tested-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
Acked-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Signed-off-by: Baruch Siach <baruch@xxxxxxxxxx>
---
 kernel/time/sched_clock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index a326f27..0b479a6 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -121,7 +121,7 @@ void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate)
 	BUG_ON(bits > 32);
 	WARN_ON(!irqs_disabled());
 	read_sched_clock = read;
-	sched_clock_mask = (1 << bits) - 1;
+	sched_clock_mask = (1ULL << bits) - 1;
 	cd.rate = rate;
 
 	/* calculate the mult/shift to convert counter ticks to ns. */
-- 
1.8.3.2

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