Public bug reported: crash autopkgtests have began to fail on arm64, as seen here:
https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac /autopkgtest-focal/focal/arm64/c/crash/20191223_190616_50c73@/log.gz The significant difference between this test and the last successful one is that the host kernel has moved from 5.3 to 5.4. As crash needs to understand some internals of the kernel memory, it often needs updates to deal with new kernels. I've verified that the existing crash still works fine w/ a 5.3 kernel[1], but does not w/ 5.4: $ sudo crash -st /usr/lib/debug/boot/vmlinux-$(uname -r) crash: cannot determine VA_BITS_ACTUAL: please use /proc/kcore However, note hte "please use /proc/kcore" - if I point crash at that instead of whatever it normally uses (/dev/mem?) it is able to start [2]. The same is also true w/ current upstream as of commit 7c2d41e btw - it fails w/o /proc/kcore and works with it. [1] ubuntu@d05-3:~$ sudo crash /usr/lib/debug/boot/vmlinux-5.3.0-26-generic crash 7.2.6 Copyright (C) 2002-2019 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "aarch64-unknown-linux-gnu"... KERNEL: /usr/lib/debug/boot/vmlinux-5.3.0-26-generic DUMPFILE: /proc/kcore CPUS: 64 DATE: Wed Jan 8 22:32:40 2020 UPTIME: 4 days, 20:46:37 LOAD AVERAGE: 1.09, 0.76, 0.46 TASKS: 836 NODENAME: d05-3 RELEASE: 5.3.0-26-generic VERSION: #28-Ubuntu SMP Wed Dec 18 05:39:18 UTC 2019 MACHINE: aarch64 (unknown Mhz) MEMORY: 127.7 GB PID: 19415 COMMAND: "crash" TASK: ffff801464623b00 [THREAD_INFO: ffff801464623b00] CPU: 13 STATE: TASK_RUNNING (ACTIVE) crash> quit [2] ubuntu@d05-3:~$ sudo crash -st /usr/lib/debug/boot/vmlinux-$(uname -r) /proc/kcore Thu Jan 9 00:20:20 2020 ubuntu@d05-3:~$ sudo crash /usr/lib/debug/boot/vmlinux-$(uname -r) /proc/kcore crash 7.2.6 Copyright (C) 2002-2019 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "aarch64-unknown-linux-gnu"... KERNEL: /usr/lib/debug/boot/vmlinux-5.4.0-9-generic DUMPFILE: /proc/kcore CPUS: 64 DATE: Thu Jan 9 00:20:57 2020 UPTIME: 03:36:15 LOAD AVERAGE: 0.56, 0.31, 0.26 TASKS: 823 NODENAME: d05-3 RELEASE: 5.4.0-9-generic VERSION: #12-Ubuntu SMP Mon Dec 16 22:33:31 UTC 2019 MACHINE: aarch64 (unknown Mhz) MEMORY: 127.7 GB PID: 44363 COMMAND: "crash" TASK: ffff00179ae0da00 [THREAD_INFO: ffff00179ae0da00] CPU: 11 STATE: TASK_RUNNING (ACTIVE) crash> ** Affects: crash (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to crash in Ubuntu. https://bugs.launchpad.net/bugs/1858958 Title: fails on arm64 w/ 5.4 kernel: crash: cannot determine VA_BITS_ACTUAL: please use /proc/kcore Status in crash package in Ubuntu: New Bug description: crash autopkgtests have began to fail on arm64, as seen here: https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac /autopkgtest-focal/focal/arm64/c/crash/20191223_190616_50c73@/log.gz The significant difference between this test and the last successful one is that the host kernel has moved from 5.3 to 5.4. As crash needs to understand some internals of the kernel memory, it often needs updates to deal with new kernels. I've verified that the existing crash still works fine w/ a 5.3 kernel[1], but does not w/ 5.4: $ sudo crash -st /usr/lib/debug/boot/vmlinux-$(uname -r) crash: cannot determine VA_BITS_ACTUAL: please use /proc/kcore However, note hte "please use /proc/kcore" - if I point crash at that instead of whatever it normally uses (/dev/mem?) it is able to start [2]. The same is also true w/ current upstream as of commit 7c2d41e btw - it fails w/o /proc/kcore and works with it. [1] ubuntu@d05-3:~$ sudo crash /usr/lib/debug/boot/vmlinux-5.3.0-26-generic crash 7.2.6 Copyright (C) 2002-2019 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "aarch64-unknown-linux-gnu"... KERNEL: /usr/lib/debug/boot/vmlinux-5.3.0-26-generic DUMPFILE: /proc/kcore CPUS: 64 DATE: Wed Jan 8 22:32:40 2020 UPTIME: 4 days, 20:46:37 LOAD AVERAGE: 1.09, 0.76, 0.46 TASKS: 836 NODENAME: d05-3 RELEASE: 5.3.0-26-generic VERSION: #28-Ubuntu SMP Wed Dec 18 05:39:18 UTC 2019 MACHINE: aarch64 (unknown Mhz) MEMORY: 127.7 GB PID: 19415 COMMAND: "crash" TASK: ffff801464623b00 [THREAD_INFO: ffff801464623b00] CPU: 13 STATE: TASK_RUNNING (ACTIVE) crash> quit [2] ubuntu@d05-3:~$ sudo crash -st /usr/lib/debug/boot/vmlinux-$(uname -r) /proc/kcore Thu Jan 9 00:20:20 2020 ubuntu@d05-3:~$ sudo crash /usr/lib/debug/boot/vmlinux-$(uname -r) /proc/kcore crash 7.2.6 Copyright (C) 2002-2019 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "aarch64-unknown-linux-gnu"... KERNEL: /usr/lib/debug/boot/vmlinux-5.4.0-9-generic DUMPFILE: /proc/kcore CPUS: 64 DATE: Thu Jan 9 00:20:57 2020 UPTIME: 03:36:15 LOAD AVERAGE: 0.56, 0.31, 0.26 TASKS: 823 NODENAME: d05-3 RELEASE: 5.4.0-9-generic VERSION: #12-Ubuntu SMP Mon Dec 16 22:33:31 UTC 2019 MACHINE: aarch64 (unknown Mhz) MEMORY: 127.7 GB PID: 44363 COMMAND: "crash" TASK: ffff00179ae0da00 [THREAD_INFO: ffff00179ae0da00] CPU: 11 STATE: TASK_RUNNING (ACTIVE) crash> To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/crash/+bug/1858958/+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
