blob: 0672c3546ae639495b8dc97768c4eafcd320da48 [file] [log] [blame]
From ee85d3967ea09b215fcea5efdd90bbbf5e74a681 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Wed, 19 Feb 2020 15:50:47 +0100
Subject: [PATCH] hwclock: fix for glibc 2.31 settimeofday()
glibc announce:
... settimeofday can no longer be used to set the time and the offset
simultaneously. If both of its two arguments are non-null, the call
will fail (setting errno to EINVAL).
It means we need to call settimeofday(NULL, tz) and settimeofday(tv, NULL).
Unfortunately, settimeofday(NULL, tz) has very special warp-clock
semantic if used as the very first settimeofday() call. It means we
have to be sure that we do not touch warp-clock if we need only need
to modify system TZ. So, let's always call settimeofday(NULL, 0)
before settimeofday(NULL, tz) for UTC rtc mode when modify system TZ.
Upstream-Status: Backport [https://github.com/karelzak/util-linux/commit/ee85d3967ea09b215fcea5efdd90bbbf5e74a681]
CC: J William Piggott <elseifthen@gmx.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
Addresses: https://github.com/karelzak/util-linux/issues/957
Signed-off-by: Liwei Song <liwei.song@windriver.com>
---
sys-utils/hwclock.c | 49 ++++++++++++++++++++++++++-------------------
1 file changed, 28 insertions(+), 21 deletions(-)
diff --git a/sys-utils/hwclock.c b/sys-utils/hwclock.c
index e736da7179f8..16576bc186ff 100644
--- a/sys-utils/hwclock.c
+++ b/sys-utils/hwclock.c
@@ -658,6 +658,9 @@ display_time(struct timeval hwctime)
* PCIL: persistent_clock_is_local, sets the "11 minute mode" timescale.
* firsttime: locks the warp_clock function (initialized to 1 at boot).
*
+ * Note that very first settimeofday(NULL, tz) modifies warp-clock as well as
+ * system TZ.
+ *
* +---------------------------------------------------------------------------+
* | op | RTC scale | settimeofday calls |
* |---------|-----------|-----------------------------------------------------|
@@ -675,41 +678,45 @@ set_system_clock(const struct hwclock_control *ctl,
struct tm broken;
int minuteswest;
int rc = 0;
- const struct timezone tz_utc = { 0 };
localtime_r(&newtime.tv_sec, &broken);
minuteswest = -get_gmtoff(&broken) / 60;
if (ctl->verbose) {
- if (ctl->hctosys && !ctl->universal)
- printf(_("Calling settimeofday(NULL, %d) to set "
- "persistent_clock_is_local.\n"), minuteswest);
- if (ctl->systz && ctl->universal)
+ if (ctl->universal)
puts(_("Calling settimeofday(NULL, 0) "
- "to lock the warp function."));
+ "to lock the warp function."));
+ else
+ printf(_("Calling settimeofday(NULL, %d) to set "
+ "persistent_clock_is_local and "
+ "the kernel timezone.\n"), minuteswest);
+
+ if (ctl->universal && minuteswest)
+ printf(_("Calling settimeofday(NULL, %d) to set "
+ "the kernel timezone.\n"), minuteswest);
+
if (ctl->hctosys)
- printf(_("Calling settimeofday(%ld.%06ld, %d)\n"),
- newtime.tv_sec, newtime.tv_usec, minuteswest);
- else {
- printf(_("Calling settimeofday(NULL, %d) "), minuteswest);
- if (ctl->universal)
- puts(_("to set the kernel timezone."));
- else
- puts(_("to warp System time."));
- }
+ printf(_("Calling settimeofday(%ld.%06ld, 0) to set "
+ "the kernel time.\n"), newtime.tv_sec, newtime.tv_usec);
}
if (!ctl->testing) {
+ const struct timezone tz_utc = { 0 };
const struct timezone tz = { minuteswest };
- if (ctl->hctosys && !ctl->universal) /* set PCIL */
+ /* warp-clock */
+ if (ctl->universal)
+ rc = settimeofday(NULL, &tz_utc); /* lock to UTC */
+ else
+ rc = settimeofday(NULL, &tz); /* set PCIL and TZ */
+
+ /* set timezone */
+ if (!rc && ctl->universal && minuteswest)
rc = settimeofday(NULL, &tz);
- if (ctl->systz && ctl->universal) /* lock warp_clock */
- rc = settimeofday(NULL, &tz_utc);
+
+ /* set time */
if (!rc && ctl->hctosys)
- rc = settimeofday(&newtime, &tz);
- else if (!rc)
- rc = settimeofday(NULL, &tz);
+ rc = settimeofday(&newtime, NULL);
if (rc) {
warn(_("settimeofday() failed"));
--
2.17.1