From 61927b9f116bf45bfdbf19dc2981d4a4f527ae5f Mon Sep 17 00:00:00 2001 From: Michael Marley Date: Mon, 7 Dec 2020 21:27:38 -0500 Subject: [PATCH] manager: Fix HW watchdog when systemd starts before driver loaded When manager_{set|override}_watchdog is called, set the watchdog timeout regardless of whether the hardware watchdog was successfully initialized. If the watchdog was requested but could not be initialized, then instead of pinging it, attempt to initialize it again. This ensures that the hardware watchdog is initialized even if the kernel module for it isn't loaded when systemd starts (which is quite likely, unless it is compiled in). This builds on work by @danc86 in https://github.com/systemd/systemd/pull/17460, but fixes the issue of not updating the watchdog timeout with the actual value from the hardware. Fixes https://github.com/systemd/systemd/issues/17838 Co-authored-by: Dan Callaghan Co-authored-by: Michael Marley --- src/core/manager.c | 42 +++++++++++++++++++++++++++++++++--------- src/core/manager.h | 3 +++ 2 files changed, 36 insertions(+), 9 deletions(-) diff --git a/src/core/manager.c b/src/core/manager.c index 1f1450b97c..4b215a6176 100644 --- a/src/core/manager.c +++ b/src/core/manager.c @@ -2937,8 +2937,10 @@ int manager_loop(Manager *m) { usec_t wait_usec, watchdog_usec; watchdog_usec = manager_get_watchdog(m, WATCHDOG_RUNTIME); - if (timestamp_is_set(watchdog_usec)) + if (m->runtime_watchdog_running) (void) watchdog_ping(); + else if (timestamp_is_set(watchdog_usec)) + manager_retry_runtime_watchdog(m); if (!ratelimit_below(&rl)) { /* Yay, something is going seriously wrong, pause a little */ @@ -3408,14 +3410,18 @@ void manager_set_watchdog(Manager *m, WatchdogType t, usec_t timeout) { if (t == WATCHDOG_RUNTIME) if (!timestamp_is_set(m->watchdog_overridden[WATCHDOG_RUNTIME])) { - if (timestamp_is_set(timeout)) + if (timestamp_is_set(timeout)) { r = watchdog_set_timeout(&timeout); - else + + if (r >= 0) + m->runtime_watchdog_running = true; + } else { watchdog_close(true); + m->runtime_watchdog_running = false; + } } - if (r >= 0) - m->watchdog[t] = timeout; + m->watchdog[t] = timeout; } int manager_override_watchdog(Manager *m, WatchdogType t, usec_t timeout) { @@ -3433,18 +3439,36 @@ int manager_override_watchdog(Manager *m, WatchdogType t, usec_t timeout) { usec_t *p; p = timestamp_is_set(timeout) ? &timeout : &m->watchdog[t]; - if (timestamp_is_set(*p)) + if (timestamp_is_set(*p)) { r = watchdog_set_timeout(p); - else + + if (r >= 0) + m->runtime_watchdog_running = true; + } else { watchdog_close(true); + m->runtime_watchdog_running = false; + } } - if (r >= 0) - m->watchdog_overridden[t] = timeout; + m->watchdog_overridden[t] = timeout; return 0; } +void manager_retry_runtime_watchdog(Manager *m) { + int r = 0; + + assert(m); + + if (timestamp_is_set(m->watchdog_overridden[WATCHDOG_RUNTIME])) + r = watchdog_set_timeout(&m->watchdog_overridden[WATCHDOG_RUNTIME]); + else + r = watchdog_set_timeout(&m->watchdog[WATCHDOG_RUNTIME]); + + if (r >= 0) + m->runtime_watchdog_running = true; +} + static void manager_deserialize_uid_refs_one_internal( Manager *m, Hashmap** uid_refs, diff --git a/src/core/manager.h b/src/core/manager.h index d22c801da8..19df889dd8 100644 --- a/src/core/manager.h +++ b/src/core/manager.h @@ -241,6 +241,8 @@ struct Manager { usec_t watchdog[_WATCHDOG_TYPE_MAX]; usec_t watchdog_overridden[_WATCHDOG_TYPE_MAX]; + bool runtime_watchdog_running; /* Whether the runtime HW watchdog was started, so we know if we still need to get the real timeout from the hardware */ + dual_timestamp timestamps[_MANAGER_TIMESTAMP_MAX]; /* Data specific to the device subsystem */ @@ -562,6 +564,7 @@ ManagerTimestamp manager_timestamp_initrd_mangle(ManagerTimestamp s); usec_t manager_get_watchdog(Manager *m, WatchdogType t); void manager_set_watchdog(Manager *m, WatchdogType t, usec_t timeout); int manager_override_watchdog(Manager *m, WatchdogType t, usec_t timeout); +void manager_retry_runtime_watchdog(Manager *m); const char* oom_policy_to_string(OOMPolicy i) _const_; OOMPolicy oom_policy_from_string(const char *s) _pure_;