From 7f3414226b58b0df0426104c8ab5e8d50ae71d11 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 15 Jan 2021 12:49:45 +0100 Subject: um: time: fix initialization in time-travel mode In time-travel mode, since my previous patch, the start time was initialized too late, so that the system would read it before we set it, thus always starting system time at 0 (1970-01-01). This happens because timekeeping_init() reads the time and is called before time_init(). Unfortunately, I didn't see this before because I was testing it only with the RTC patch applied (and enabled), and then the time is read again by the RTC a little - after time_init() this time. Fix this by just doing the initialization whenever necessary. Fixes: 2701c1bd91dd ("um: time: Fix read_persistent_clock64() in time-travel") Signed-off-by: Johannes Berg Signed-off-by: Richard Weinberger --- arch/um/kernel/time.c | 50 +++++++++++++++++++++++++++++++------------------- 1 file changed, 31 insertions(+), 19 deletions(-) (limited to 'arch/um') diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c index f4db89b5b5a6..315248b03941 100644 --- a/arch/um/kernel/time.c +++ b/arch/um/kernel/time.c @@ -535,6 +535,31 @@ invalid_number: return 1; } + +static void time_travel_set_start(void) +{ + if (time_travel_start_set) + return; + + switch (time_travel_mode) { + case TT_MODE_EXTERNAL: + time_travel_start = time_travel_ext_req(UM_TIMETRAVEL_GET_TOD, -1); + /* controller gave us the *current* time, so adjust by that */ + time_travel_ext_get_time(); + time_travel_start -= time_travel_time; + break; + case TT_MODE_INFCPU: + case TT_MODE_BASIC: + if (!time_travel_start_set) + time_travel_start = os_persistent_clock_emulation(); + break; + case TT_MODE_OFF: + /* we just read the host clock with os_persistent_clock_emulation() */ + break; + } + + time_travel_start_set = true; +} #else /* CONFIG_UML_TIME_TRAVEL_SUPPORT */ #define time_travel_start_set 0 #define time_travel_start 0 @@ -553,6 +578,10 @@ static void time_travel_set_interval(unsigned long long interval) { } +static inline void time_travel_set_start(void) +{ +} + /* fail link if this actually gets used */ extern u64 time_travel_ext_req(u32 op, u64 time); @@ -731,6 +760,8 @@ void read_persistent_clock64(struct timespec64 *ts) { long long nsecs; + time_travel_set_start(); + if (time_travel_mode != TT_MODE_OFF) nsecs = time_travel_start + time_travel_time; else @@ -742,25 +773,6 @@ void read_persistent_clock64(struct timespec64 *ts) void __init time_init(void) { -#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT - switch (time_travel_mode) { - case TT_MODE_EXTERNAL: - time_travel_start = time_travel_ext_req(UM_TIMETRAVEL_GET_TOD, -1); - /* controller gave us the *current* time, so adjust by that */ - time_travel_ext_get_time(); - time_travel_start -= time_travel_time; - break; - case TT_MODE_INFCPU: - case TT_MODE_BASIC: - if (!time_travel_start_set) - time_travel_start = os_persistent_clock_emulation(); - break; - case TT_MODE_OFF: - /* we just read the host clock with os_persistent_clock_emulation() */ - break; - } -#endif - timer_set_signal_handler(); late_time_init = um_timer_setup; } -- cgit v1.2.3-59-g8ed1b