hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8LQCC CVE: NA ------------------------------------------------- The period of the secure timer is set to 3s by BIOS. That means the secure timer interrupt will trigger every 3 seconds. To further decrease the NMI watchdog's effect on performance, this patch set the period of the secure timer base on 'watchdog_thresh'. This variable is initiallized to 10s. We can also set the period at runtime by modifying '/proc/sys/kernel/watchdog_thresh' Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Conflicts: arch/arm64/kernel/watchdog_sdei.c (context conflict) Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> --- arch/arm64/kernel/watchdog_sdei.c | 13 +++++++++++++ drivers/firmware/arm_sdei.c | 6 ++++++ include/linux/arm_sdei.h | 1 + include/uapi/linux/arm_sdei.h | 1 + 4 files changed, 21 insertions(+) diff --git a/arch/arm64/kernel/watchdog_sdei.c b/arch/arm64/kernel/watchdog_sdei.c index 7ebf6b5ab237..758e20eadc31 100644 --- a/arch/arm64/kernel/watchdog_sdei.c +++ b/arch/arm64/kernel/watchdog_sdei.c @@ -33,6 +33,8 @@ void watchdog_hardlockup_enable(unsigned int cpu) /* Skip the first hardlockup check incase BIOS didn't init the * secure timer correctly */ watchdog_hardlockup_touch_cpu(cpu); + sdei_api_set_secure_timer_period(watchdog_thresh); + ret = sdei_api_event_enable(sdei_watchdog_event_num); if (ret) { pr_err("Enable NMI Watchdog failed on cpu%d\n", @@ -102,6 +104,17 @@ int __init watchdog_hardlockup_probe(void) return sdei_watchdog_event_num; } + /* + * After we introduced 'sdei_api_set_secure_timer_period', we disselect + * 'CONFIG_HARDLOCKUP_CHECK_TIMESTAMP'. So we need to make sure that + * firmware can set the period of the secure timer and the timer + * interrupt doesn't trigger too soon. + */ + if (sdei_api_set_secure_timer_period(watchdog_thresh)) { + pr_err("Firmware doesn't support setting the secure timer period, please update your BIOS !\n"); + return -EINVAL; + } + on_each_cpu(sdei_nmi_watchdog_bind, NULL, true); ret = sdei_event_register(sdei_watchdog_event_num, diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c index 5e229d3eb552..0f7ef69071c0 100644 --- a/drivers/firmware/arm_sdei.c +++ b/drivers/firmware/arm_sdei.c @@ -204,6 +204,12 @@ int sdei_api_clear_eoi(int hwirq) NULL); } +int sdei_api_set_secure_timer_period(int sec) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SET_SECURE_TIMER_PERIOD, sec, 0, 0, 0, + 0, NULL); +} + static int sdei_api_event_get_info(u32 event, u32 info, u64 *result) { return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0, diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h index 6381537e7015..28e247dd5773 100644 --- a/include/linux/arm_sdei.h +++ b/include/linux/arm_sdei.h @@ -40,6 +40,7 @@ int sdei_api_event_interrupt_bind(int hwirq); int sdei_api_event_disable(u32 event_num); int sdei_api_event_enable(u32 event_num); int sdei_api_clear_eoi(int hwirq); +int sdei_api_set_secure_timer_period(int sec); /* GHES register/unregister helpers */ int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb, diff --git a/include/uapi/linux/arm_sdei.h b/include/uapi/linux/arm_sdei.h index 1187b1b49c87..a5375679dd50 100644 --- a/include/uapi/linux/arm_sdei.h +++ b/include/uapi/linux/arm_sdei.h @@ -25,6 +25,7 @@ #define SDEI_1_0_FN_SDEI_PRIVATE_RESET SDEI_1_0_FN(0x11) #define SDEI_1_0_FN_SDEI_SHARED_RESET SDEI_1_0_FN(0x12) #define SDEI_1_0_FN_SDEI_CLEAR_EOI SDEI_1_0_FN(0x18) +#define SDEI_1_0_FN_SET_SECURE_TIMER_PERIOD SDEI_1_0_FN(0x19) #define SDEI_VERSION_MAJOR_SHIFT 48 #define SDEI_VERSION_MAJOR_MASK 0x7fff -- 2.20.1