From a03ff6f20c396fb84cf61501a31fefdf0a5eb5a7 Mon Sep 17 00:00:00 2001 From: Pavel Machek Date: Mon, 26 Jan 2015 14:43:04 +0100 Subject: [PATCH] PM / sleep: Mention async suspend in PM_TRACE documentation Document pm_tracing actually affecting suspend in non-trivial way. Signed-off-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- Documentation/power/s2ram.txt | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/power/s2ram.txt b/Documentation/power/s2ram.txt index 1bdfa0443773..4685aee197fd 100644 --- a/Documentation/power/s2ram.txt +++ b/Documentation/power/s2ram.txt @@ -69,6 +69,10 @@ Reason for this is that the RTC is the only reliably available piece of hardware during resume operations where a value can be set that will survive a reboot. +pm_trace is not compatible with asynchronous suspend, so it turns +asynchronous suspend off (which may work around timing or +ordering-sensitive bugs). + Consequence is that after a resume (even if it is successful) your system clock will have a value corresponding to the magic number instead of the correct date/time! It is therefore advisable to use a program like ntp-date -- 2.34.1