diff options
| -rw-r--r-- | kernel.spec | 9 | ||||
| -rw-r--r-- | ntp-Make-periodic-RTC-update-more-reliable.patch | 44 |
2 files changed, 53 insertions, 0 deletions
diff --git a/kernel.spec b/kernel.spec index cd236a5b2..08db63a3d 100644 --- a/kernel.spec +++ b/kernel.spec @@ -759,6 +759,9 @@ Patch25104: ansi_cprng-Fix-off-by-one-error-in-non-block-size-request.patch Patch25103: fix-arm-btrfs-build.patch +#rhbz 985522 +Patch25107: ntp-Make-periodic-RTC-update-more-reliable.patch + # END OF PATCH DEFINITIONS %endif @@ -1478,6 +1481,9 @@ ApplyPatch fix-arm-btrfs-build.patch #CVE-2013-4345 rhbz 1007690 1009136 ApplyPatch ansi_cprng-Fix-off-by-one-error-in-non-block-size-request.patch +#rhbz 985522 +ApplyPatch ntp-Make-periodic-RTC-update-more-reliable.patch + # END OF PATCH APPLICATIONS %endif @@ -2282,6 +2288,9 @@ fi # ||----w | # || || %changelog +* Fri Sep 20 2013 Josh Boyer <jwboyer@fedoraproject.org> +- Fix RTC updates from ntp (rhbz 985522) + * Fri Sep 20 2013 Josh Boyer <jwboyer@fedoraproject.org> - 3.12.0-0.rc1.git4.1 - Linux v3.12-rc1-250-g7b9e3a6 diff --git a/ntp-Make-periodic-RTC-update-more-reliable.patch b/ntp-Make-periodic-RTC-update-more-reliable.patch new file mode 100644 index 000000000..59179e719 --- /dev/null +++ b/ntp-Make-periodic-RTC-update-more-reliable.patch @@ -0,0 +1,44 @@ +From a97ad0c4b447a132a322cedc3a5f7fa4cab4b304 Mon Sep 17 00:00:00 2001 +From: Miroslav Lichvar <mlichvar@redhat.com> +Date: Thu, 1 Aug 2013 19:31:35 +0200 +Subject: [PATCH] ntp: Make periodic RTC update more reliable + +The current code requires that the scheduled update of the RTC happens +in the closest tick to the half of the second. This seems to be +difficult to achieve reliably. The scheduled work may be missing the +target time by a tick or two and be constantly rescheduled every second. + +Relax the limit to 10 ticks. As a typical RTC drifts in the 11-minute +update interval by several milliseconds, this shouldn't affect the +overall accuracy of the RTC much. + +Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com> +Signed-off-by: John Stultz <john.stultz@linaro.org> +--- + kernel/time/ntp.c | 3 ++- + 1 file changed, 2 insertions(+), 1 deletion(-) + +diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c +index 8f5b3b9..ab1fa7c 100644 +--- a/kernel/time/ntp.c ++++ b/kernel/time/ntp.c +@@ -475,6 +475,7 @@ static void sync_cmos_clock(struct work_struct *work) + * called as close as possible to 500 ms before the new second starts. + * This code is run on a timer. If the clock is set, that timer + * may not expire at the correct time. Thus, we adjust... ++ * We want the clock to be within a couple of ticks from the target. + */ + if (!ntp_synced()) { + /* +@@ -485,7 +486,7 @@ static void sync_cmos_clock(struct work_struct *work) + } + + getnstimeofday(&now); +- if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) { ++ if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec * 5) { + struct timespec adjust = now; + + fail = -ENODEV; +-- +1.7.9.5 + |