From b2f21d1b7bc80150f2b7d1fecae5f64c9ead26fa Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Wed, 10 Dec 2014 11:02:09 +0000 Subject: clocksource: arch_timer: Only use the virtual counter (CNTVCT) on arm64 commit d6ad36913083d683aad4e02e53580c995f1a6ede upstream. Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical timers when requested) introduces the use of physical counters in the ARM architected timer driver. However, he arm64 kernel uses CNTVCT in VDSO. When booting in EL2, the kernel switches to the physical timers to make things easier for KVM but it continues to use the virtual counter both in user and kernel. While in such scenario CNTVCT == CNTPCT (since CNTVOFF is initialised by the kernel to 0), we want to spot firmware bugs corrupting CNTVOFF early (which would affect CNTVCT). Signed-off-by: Catalin Marinas Tested-by: Yingjoe Chen Cc: Daniel Lezcano Signed-off-by: Arnd Bergmann Fixes: 0b46b8a718c6 ("clocksource: arch_timer: Fix code to use physical timers when requested") Cc: Ian Campbell Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman --- 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 1fa2af957b18..84b4c8b7fbd1 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) /* Register the CP15 based counter if we have one */ if (type & ARCH_CP15_TIMER) { - if (arch_timer_use_virtual) + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) arch_timer_read_counter = arch_counter_get_cntvct; else arch_timer_read_counter = arch_counter_get_cntpct; -- cgit v1.2.3