Hybrid Automata monitors hook into the DA implementation when doing da_monitor_reset(). This function is called both on initialisation and teardown, HA monitors try to cancel a timer only when it's initialised relying on the da_mon->monitoring flag. This flag could however be corrupted during initialisation. This happens for instance on per-task monitors that share the same storage with different type of monitors like LTL or in case of races during a previous teardown.
Stop relying on the monitoring flag during initialisation, assume that can have any value, so skip timer cancellation in any case when a local flag is set. New monitors (e.g. new tasks) are always zero-initialised so they are safe. Reported-by: Wen Yang <[email protected]> Closes: https://lore.kernel.org/lkml/d02c656aada7d071f083460a5c9a454363669b61.1778522945.git.wen.y...@linux.dev Fixes: f5587d1b6ec9 ("rv: Add Hybrid Automata monitor type") Signed-off-by: Gabriele Monaco <[email protected]> --- include/rv/ha_monitor.h | 31 ++++++++++++++++++- kernel/trace/rv/monitors/nomiss/nomiss.c | 4 +-- kernel/trace/rv/monitors/opid/opid.c | 4 +-- kernel/trace/rv/monitors/stall/stall.c | 4 +-- .../rvgen/rvgen/templates/dot2k/main.c | 4 +-- 5 files changed, 38 insertions(+), 9 deletions(-) diff --git a/include/rv/ha_monitor.h b/include/rv/ha_monitor.h index 47ff1a41febe..11ae85bad492 100644 --- a/include/rv/ha_monitor.h +++ b/include/rv/ha_monitor.h @@ -116,6 +116,35 @@ static enum hrtimer_restart ha_monitor_timer_callback(struct hrtimer *hrtimer); #define ha_get_ns() 0 #endif /* HA_CLK_NS */ +static bool ha_mon_initializing; + +static int ha_monitor_init(void) +{ + int ret; + + ha_mon_initializing = true; + ret = da_monitor_init(); + ha_mon_initializing = false; + return ret; +} + +static void ha_monitor_destroy(void) +{ + da_monitor_destroy(); +} + +/* + * ha_monitor_uninitialized - are fields like the timer initialized? + * + * On a clean monitor, we can assume an active monitor (monitoring) is + * initialized, however the monitoring field cannot be trusted during + * initialization. + */ +static inline bool ha_monitor_uninitialized(struct da_monitor *da_mon) +{ + return ha_mon_initializing || !da_monitoring(da_mon); +} + /* Should be supplied by the monitor */ static u64 ha_get_env(struct ha_monitor *ha_mon, enum envs env, u64 time_ns); static bool ha_verify_constraint(struct ha_monitor *ha_mon, @@ -160,7 +189,7 @@ static inline void ha_monitor_reset_env(struct da_monitor *da_mon) struct ha_monitor *ha_mon = to_ha_monitor(da_mon); /* Initialisation resets the monitor before initialising the timer */ - if (likely(da_monitoring(da_mon))) + if (likely(!ha_monitor_uninitialized(da_mon))) ha_cancel_timer(ha_mon); } diff --git a/kernel/trace/rv/monitors/nomiss/nomiss.c b/kernel/trace/rv/monitors/nomiss/nomiss.c index 31f90f3638d8..8ead8783c29f 100644 --- a/kernel/trace/rv/monitors/nomiss/nomiss.c +++ b/kernel/trace/rv/monitors/nomiss/nomiss.c @@ -227,7 +227,7 @@ static int enable_nomiss(void) { int retval; - retval = da_monitor_init(); + retval = ha_monitor_init(); if (retval) return retval; @@ -263,7 +263,7 @@ static void disable_nomiss(void) rv_detach_trace_probe("nomiss", sched_switch, handle_sched_switch); rv_detach_trace_probe("nomiss", sched_wakeup, handle_sched_wakeup); - da_monitor_destroy(); + ha_monitor_destroy(); } static struct rv_monitor rv_this = { diff --git a/kernel/trace/rv/monitors/opid/opid.c b/kernel/trace/rv/monitors/opid/opid.c index 4594c7c46601..2922318c6112 100644 --- a/kernel/trace/rv/monitors/opid/opid.c +++ b/kernel/trace/rv/monitors/opid/opid.c @@ -73,7 +73,7 @@ static int enable_opid(void) { int retval; - retval = da_monitor_init(); + retval = ha_monitor_init(); if (retval) return retval; @@ -90,7 +90,7 @@ static void disable_opid(void) rv_detach_trace_probe("opid", sched_set_need_resched_tp, handle_sched_need_resched); rv_detach_trace_probe("opid", sched_waking, handle_sched_waking); - da_monitor_destroy(); + ha_monitor_destroy(); } /* diff --git a/kernel/trace/rv/monitors/stall/stall.c b/kernel/trace/rv/monitors/stall/stall.c index 9ccfda6b0e73..3c38fb1a0159 100644 --- a/kernel/trace/rv/monitors/stall/stall.c +++ b/kernel/trace/rv/monitors/stall/stall.c @@ -103,7 +103,7 @@ static int enable_stall(void) { int retval; - retval = da_monitor_init(); + retval = ha_monitor_init(); if (retval) return retval; @@ -120,7 +120,7 @@ static void disable_stall(void) rv_detach_trace_probe("stall", sched_switch, handle_sched_switch); rv_detach_trace_probe("stall", sched_wakeup, handle_sched_wakeup); - da_monitor_destroy(); + ha_monitor_destroy(); } static struct rv_monitor rv_this = { diff --git a/tools/verification/rvgen/rvgen/templates/dot2k/main.c b/tools/verification/rvgen/rvgen/templates/dot2k/main.c index bf0999f6657a..889446760e3c 100644 --- a/tools/verification/rvgen/rvgen/templates/dot2k/main.c +++ b/tools/verification/rvgen/rvgen/templates/dot2k/main.c @@ -35,7 +35,7 @@ static int enable_%%MODEL_NAME%%(void) { int retval; - retval = da_monitor_init(); + retval = %%MONITOR_CLASS%%_monitor_init(); if (retval) return retval; @@ -50,7 +50,7 @@ static void disable_%%MODEL_NAME%%(void) %%TRACEPOINT_DETACH%% - da_monitor_destroy(); + %%MONITOR_CLASS%%_monitor_destroy(); } /* -- 2.54.0
