From fb960c041059841a7408541f36d4239ada7b4cc3 Mon Sep 17 00:00:00 2001 From: Xiongfeng Wang Date: Sat, 20 Feb 2021 11:00:59 +0800 Subject: [PATCH] sdei_watchdog: refresh 'last_timestamp' when enabling nmi_watchdog commit 5bc048a102ef9c3748464cacce443a0f1d9bed5b openeuler. The trigger period of secure time is set by firmware. We need to check the time_stamp every time the secure time fires to make sure the hardlockup detection is not executed too soon. We need to refresh 'last_timestamp' to the current time when we enable the nmi_watchdog. Otherwise, false hardlockup may be detected when the secure timer fires the first time. Signed-off-by: huwentao --- arch/arm64/kernel/watchdog_sdei.c | 2 ++ include/linux/nmi.h | 1 + kernel/watchdog_hld.c | 9 +++++++++ 3 files changed, 12 insertions(+) diff --git a/arch/arm64/kernel/watchdog_sdei.c b/arch/arm64/kernel/watchdog_sdei.c index a2154aa6f27a..e36c4d398893 100644 --- a/arch/arm64/kernel/watchdog_sdei.c +++ b/arch/arm64/kernel/watchdog_sdei.c @@ -30,6 +30,8 @@ int watchdog_nmi_enable(unsigned int cpu) if (!sdei_watchdog_registered) return -EINVAL; + refresh_hld_last_timestamp(); + ret = sdei_api_event_enable(sdei_watchdog_event_num); if (ret) { pr_err("Enable NMI Watchdog failed on cpu%d\n", diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 27504f47add0..e2f09e60d0d9 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -208,6 +208,7 @@ u64 hw_nmi_get_sample_period(int watchdog_thresh); #if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \ defined(CONFIG_HARDLOCKUP_DETECTOR) void watchdog_update_hrtimer_threshold(u64 period); +void refresh_hld_last_timestamp(void); #else static inline void watchdog_update_hrtimer_threshold(u64 period) { } #endif diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c index 76ac86caa50f..88f5c314a1df 100644 --- a/kernel/watchdog_hld.c +++ b/kernel/watchdog_hld.c @@ -89,6 +89,15 @@ static bool watchdog_check_timestamp(void) __this_cpu_write(last_timestamp, now); return true; } + +void refresh_hld_last_timestamp(void) +{ + ktime_t now; + + now = ktime_get_mono_fast_ns(); + __this_cpu_write(last_timestamp, now); + +} #else static inline bool watchdog_check_timestamp(void) {