Well, there was a regression when I first uploaded the fix and we noticed that during dump, if there was a hotplug event, it would kill makedumpfile before it completed. When restarting, makedumpfile would find the same file already there, which would prevent the new dump to even start, so the system would reboot with an incomplete dump. That was reported and fixed as LP bug 1811692.
So, I agree that a backport to xenial should already include the fix to bug 1828596, but these changes are not without their regression potentials. The good thing is that we caught this with our current testing, so I would say our testing so far has helped us prevent a big regression. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1655280 Title: ISST-LTE:pVM:roselp4:ubuntu 16.04: cp: error reading '/proc/vmcore': Bad address when trying to dump vmcore Status in The Ubuntu-power-systems project: In Progress Status in linux package in Ubuntu: Invalid Status in makedumpfile package in Ubuntu: Fix Released Status in linux source package in Xenial: Invalid Status in makedumpfile source package in Xenial: New Status in linux source package in Bionic: Invalid Status in makedumpfile source package in Bionic: Fix Released Status in linux source package in Cosmic: Invalid Status in makedumpfile source package in Cosmic: Fix Released Status in linux source package in Disco: Invalid Status in makedumpfile source package in Disco: Fix Released Bug description: [Impact] After a DLPAR memory/CPU add/remove operation, kdump tools need to be restarted or else kdump tools will fail to capture the crash. [Test] == Comment: #0 - Ping Tian Han <pt...@cn.ibm.com> - 2017-01-09 02:51:00 == ---Problem Description--- Vmcore cannot be saved when triggering bug 150353 on roselp4: Copying data : [ 2.0 %] \/usr/sbin/kdump-config: line 591: 5502 Bus error makedumpfile $MAKEDUMP_ARGS $vmcore_file $KDUMP_CORETEMP [ 512.833872] kdump-tools[5450]: * kdump-tools: makedumpfile failed, falling back to 'cp' [ 573.595449] kdump-tools[5450]: cp: error reading '/proc/vmcore': Bad address [ 573.605717] kdump-tools[5450]: * kdump-tools: failed to save vmcore in /var/crash/201701090223 [ 573.765417] kdump-tools[5450]: * running makedumpfile --dump-dmesg /proc/vmcore /var/crash/201701090223/dmesg.201701090223 [ 574.285506] kdump-tools[5450]: The kernel version is not supported. [ 574.285672] kdump-tools[5450]: The makedumpfile operation may be incomplete. [ 574.285767] kdump-tools[5450]: The dmesg log is saved to /var/crash/201701090223/dmesg.201701090223. [ 574.305422] kdump-tools[5450]: makedumpfile Completed. [ 574.315363] kdump-tools[5450]: * kdump-tools: saved dmesg content in /var/crash/201701090223 [ 574.615688] kdump-tools[5450]: Mon, 09 Jan 2017 02:24:26 -0600 [ 574.705384] kdump-tools[5450]: Rebooting. Stopping ifup for ib0... [ OK ] Stopped ifup for ib0. [ 1008.579897] reboot: Restarting system Contact Information = Ping Tian Han/pt...@cn.ibm.com Carrie Mitsuyoshi/carri...@us.ibm.com ---uname output--- Linux roselp4 4.8.0-34-generic #36~16.04.1-Ubuntu SMP Wed Dec 21 18:53:20 UTC 2016 ppc64le ppc64le ppc64le GNU/Linux Machine Type = lpar ---Debugger--- A debugger is not configured ---Steps to Reproduce--- 1. config kdump on roselp4 2. try to trigger bug 150353 *Additional Instructions for Ping Tian Han/pt...@cn.ibm.com Carrie Mitsuyoshi/carri...@us.ibm.com: -Post a private note with access information to the machine that the bug is occuring on. == Comment: #3 - Brahadambal Srinivasan <brsri...@in.ibm.com> - 2017-01-10 02:42:25 == root@roselp4:~# cat /proc/cmdline BOOT_IMAGE=/boot/vmlinux-4.8.0-34-generic root=UUID=0bcf3431-df8b-499c-9a13-33070f242e0c ro splash quiet crashkernel=384M-:512M root@roselp4:~# dmesg | grep Reser [ 0.000000] Reserving 512MB of memory at 128MB for crashkernel (System RAM: 21760MB) [Regression Potential] The fix applies to makedumpfile, and could impact dump capture. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1655280/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
