Hi, On Wed, Jun 15, 2016 at 08:00:30AM +0000, Usyskin, Alexander wrote: > I assume that "This happened with 4.6, but not with v4.5.", yes? Yes, sorry. > Do you have vPro system? Yes, my CPU is i7-5600U. > Have you provisioned your ME device? No, I don't think so. > If not, the iAMT watchdog should not be exposed to user-space and > should not affect systemd. Do you have /dev/watchdog* with identity > "iamt_wdt" at you system? # ls /sys/class/watchdog watchdog0 # wd_identify iTCO_wdt That's also, what was used by systemd: Jun 15 01:24:49 earth kernel: iTCO_wdt: Intel TCO WatchDog Timer Driver v1.11 Jun 15 01:24:49 earth kernel: iTCO_wdt: Found a Wildcat Point_LP TCO device (Version=2, TCOBASE=0x1860) Jun 15 01:24:49 earth kernel: iTCO_wdt: initialized. heartbeat=30 sec (nowayout=0) Jun 15 01:24:49 earth systemd[1]: Hardware watchdog 'iTCO_wdt', version 0 Jun 15 01:24:49 earth systemd[1]: Set hardware watchdog to 30s. I have checked with wd_keepalive and I have a few more observations: * The freeze did not appear when wd_keepalive is used instead of systemd * The freeze appears, if I kill wd_keepalive, so the freeze itself seems to be a bug in the iTCO_wdt driver/hardware. So looks like fdd9b8655933 somehow results in systemd being too slow to ping the watchdog in time. -- Sebastian > -----Original Message----- > From: Sebastian Reichel [mailto:sre@debian.org] > Sent: Wednesday, June 15, 2016 02:44 > To: Debian Bug Tracking System <submit@bugs.debian.org> > Subject: Bug#827323: linux: Regression v4.5 -> v4.6: system freeze after suspend/resume due to iAMT watchdog > > Source: linux > Version: 4.5.5-1 > Severity: normal > > Hi, > > My Lenovo Thinkpad X250 freezes a couple of seconds after resuming > from suspend. This happened with 4.5, but not with v4.6. I > bisected the problem using mainline kernel with Debian config to > the following commit: > > sre@earth ~/src/linux (git)-[fdd9b86...|bisect] % git bisect bad > fdd9b8655933c3eb3154fe1ed351c17b654258bd is the first bad commit commit fdd9b8655933c3eb3154fe1ed351c17b654258bd > Author: Alexander Usyskin <alexander.usyskin@intel.com> > Date: Fri Jan 8 00:49:21 2016 +0200 > > mei: wd: drop the watchdog code from the core mei driver > > Instead of integrating the iAMT watchdog in the mei core driver > we will create a watchdog device on the mei client bus and > create a driver for it. > > This patch removes the watchdog code from the mei core driver. > > Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> > Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > My system was configured to use the watchdog via "RuntimeWatchdogSec=30" > in "/etc/systemd/system.conf". After disabling the feature no system freeze > happens after suspend/resume cycle. > > -- Sebastian > > -- System Information: > Debian Release: stretch/sid > APT prefers testing > APT policy: (1000, 'testing'), (500, 'unstable'), (200, 'experimental') > Architecture: amd64 (x86_64) > Foreign Architectures: i386, armhf > > Kernel: Linux 4.6.0-1-amd64 (SMP w/4 CPU cores) > Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) > Shell: /bin/sh linked to /bin/dash > Init: systemd (via /run/systemd/system) > --------------------------------------------------------------------- > Intel Israel (74) Limited > > This e-mail and any attachments may contain confidential material for > the sole use of the intended recipient(s). Any review or distribution > by others is strictly prohibited. If you are not the intended > recipient, please contact the sender and delete all copies. >
Attachment:
signature.asc
Description: PGP signature