The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2c33d775ef4c25c0e1e1cc0fd5496d02f76bfa20 Mon Sep 17 00:00:00 2001 From: Kurt Kanzenbach kurt@linutronix.de Date: Thu, 28 Apr 2022 08:24:32 +0200 Subject: [PATCH] timekeeping: Mark NMI safe time accessors as notrace
Mark the CLOCK_MONOTONIC fast time accessors as notrace. These functions are used in tracing to retrieve timestamps, so they should not recurse.
Fixes: 4498e7467e9e ("time: Parametrize all tk_fast_mono users") Fixes: f09cb9a1808e ("time: Introduce tk_fast_raw") Reported-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Kurt Kanzenbach kurt@linutronix.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220426175338.3807ca4f@gandalf.local.home/ Link: https://lore.kernel.org/r/20220428062432.61063-1-kurt@linutronix.de
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index dcdcb85121e4..3b1398fbddaf 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -482,7 +482,7 @@ static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf) * of the following timestamps. Callers need to be aware of that and * deal with it. */ -u64 ktime_get_mono_fast_ns(void) +u64 notrace ktime_get_mono_fast_ns(void) { return __ktime_get_fast_ns(&tk_fast_mono); } @@ -494,7 +494,7 @@ EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns); * Contrary to ktime_get_mono_fast_ns() this is always correct because the * conversion factor is not affected by NTP/PTP correction. */ -u64 ktime_get_raw_fast_ns(void) +u64 notrace ktime_get_raw_fast_ns(void) { return __ktime_get_fast_ns(&tk_fast_raw); }