On 04/16/2015 04:36 PM, Andreas Henriksson wrote: > Hello! > > The below forwarded issue seems to have been introduced in > commit ab8f402952301106ad0bd5c5a51dc > "hwclock: don't confuse users with select() timeout warning" > > This issue is also tracked at http://bugs.debian.org/782726 > > Regards, > Andreas Henriksson > > ----- Forwarded message from Serge Schneider <serge@xxxxxxxxxxxxxxx> ----- > > Date: Thu, 16 Apr 2015 20:24:26 +0100 > From: Serge Schneider <serge@xxxxxxxxxxxxxxx> > To: submit@xxxxxxxxxxxxxxx > Subject: Bug#782726: util-linux: hwclock's synchronize_to_clock_tick_rtc > returns inconsistent values > User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 > Thunderbird/31.6.0 > > Package: util-linux > Version: 2.25.2-6 > Severity: normal > > Dear Maintainer, > rc = select(rtc_fd + 1, &rfds, NULL, NULL, &tv); > ret = 1; > if (rc == -1) > warn(_("select() to %s to wait for clock tick > failed"), > rtc_dev_name); > else if (rc == 0 && debug) > printf(_("select() to %s to wait for clock > tick timed out"), > rtc_dev_name); > else > ret = 0; > Karel, The select time out still needs to return 1, so the debug test should have been a separate statement. I don't have time to patch and test this right now, but I can do it later if you want? > When 'select' times out and returns 0, synchronize_to_clock_tick_rtc returns > either 1 or 0, depnding on whether the -D option (debug) was used. This causes > hwclock -r to succeed and hwclock -r -D to return an error. In one case, it > just fails, in the other, the values are off by the timeout period (10 > seconds, in this version). > > pi@test-pi ~/dev/util-linux-2.25.2 $ sudo ./hwclock -r > Thu 16 Apr 2015 19:18:44 UTC -10.016913 seconds > pi@test-pi ~/dev/util-linux-2.25.2 $ sudo ./hwclock -r -D > hwclock from util-linux 2.25.2 > Using the /dev interface to the clock. > Last drift adjustment done at 1429205484 seconds after 1969 > Last calibration done at 1429205484 seconds after 1969 > Hardware clock is on UTC time > Assuming hardware clock is kept in UTC time. > Waiting for clock tick... > select() to /dev/rtc0 to wait for clock tick timed out...synchronization > failed > > ----- End forwarded message ----- > -- > To unsubscribe from this list: send the line "unsubscribe util-linux" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
