[PATCH 1/2] PM: base: power: don't try to use non-existing RTC for storing data
From: Juergen Gross <jgross@suse.com>
Date: 2021-09-03 08:49:45
Also in:
lkml, stable, xen-devel
Subsystem:
driver core, kobjects, debugfs and sysfs, hibernation (aka software suspend, aka swsusp), power management core, suspend to ram, the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Linus Torvalds
In there is no legacy RTC device, don't try to use it for storing trace data across suspend/resume. Cc: <redacted> Signed-off-by: Juergen Gross <jgross@suse.com> --- drivers/base/power/trace.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index a97f33d0c59f..b7c80849455c 100644
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c@@ -13,6 +13,7 @@ #include <linux/export.h> #include <linux/rtc.h> #include <linux/suspend.h> +#include <linux/init.h> #include <linux/mc146818rtc.h>
@@ -165,6 +166,9 @@ void generate_pm_trace(const void *tracedata, unsigned int user) const char *file = *(const char **)(tracedata + 2); unsigned int user_hash_value, file_hash_value; + if (!x86_platform.legacy.rtc) + return 0; + user_hash_value = user % USERHASH; file_hash_value = hash_string(lineno, file, FILEHASH); set_magic_time(user_hash_value, file_hash_value, dev_hash_value);
@@ -267,6 +271,9 @@ static struct notifier_block pm_trace_nb = { static int __init early_resume_init(void) { + if (!x86_platform.legacy.rtc) + return 0; + hash_value_early_read = read_magic_time(); register_pm_notifier(&pm_trace_nb); return 0;
@@ -277,6 +284,9 @@ static int __init late_resume_init(void) unsigned int val = hash_value_early_read; unsigned int user, file, dev; + if (!x86_platform.legacy.rtc) + return 0; + user = val % USERHASH; val = val / USERHASH; file = val % FILEHASH;
--
2.26.2