[PATCH 1/2][Artful] clocksource/drivers/arm_arch_timer: Fix mem frame loop initialization

dann frazier dann.frazier at canonical.com
Tue Aug 29 23:18:11 UTC 2017

From: Matthias Kaehlcke <mka at chromium.org>

BugLink: https://bugs.launchpad.net/bugs/1713821

The loop to find the best memory frame in arch_timer_mem_acpi_init()
initializes the loop counter with itself ('i = i'), which is suspicious
in the first place and pointed out by clang. The loop condition is
'i < timer_count' and a prior for loop exits when 'i' reaches
'timer_count', therefore the second loop is never executed.

Initialize the loop counter with 0 to iterate over all timers, which
supposedly was the intention before the typo monster attacked.

Fixes: c2743a36765d3 ("clocksource: arm_arch_timer: add GTDT support for memory-mapped timer")
Signed-off-by: Matthias Kaehlcke <mka at chromium.org>
Reported-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
Acked-by: Mark Rutland <mark.rutland at arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano at linaro.org>
(cherry picked from commit d197f7988721221fac64f899efd7657c15281810)
Signed-off-by: dann frazier <dann.frazier at canonical.com>
 drivers/clocksource/arm_arch_timer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 8b5c30062d99..6568e6a10840 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1440,7 +1440,7 @@ static int __init arch_timer_mem_acpi_init(int platform_timer_count)
 	 * While unlikely, it's theoretically possible that none of the frames
 	 * in a timer expose the combination of feature we want.
-	for (i = i; i < timer_count; i++) {
+	for (i = 0; i < timer_count; i++) {
 		timer = &timers[i];
 		frame = arch_timer_mem_find_best_frame(timer);

More information about the kernel-team mailing list