[Crash-utility] [ANNOUNCE] crash version 5.0.4 is available

[Dave Anderson]

- Fix for the x86 "bt" command when a newly-forked task's resumption
  EIP address value is set to the "ret_from_fork" entry point by 
  copy_thread().  Without the patch, the backtrace attempt would 
  display "bt: cannot resolve stack trace", dump the text symbols on
  the stack, and a possible USER-MODE exception frame.            
  (anderson at redhat.com)

- Fix for the x86 "bt" command if the kdump-generated NMI interrupts
  a task running in kernel space at a point in the system_call entry 
  point code prior to the call to a system call function.  Without the 
  patch, the backtrace attempt would display "bt: cannot resolve stack 
  trace", dump the text symbols on the kernel stack, and display any
  "KERNEL-MODE" exception frames followed by a possible "USER-MODE" 
  exception frame.
  (anderson at redhat.com)

- Fix for the "bt" command on 2.6.29 and later x86_64 kernels to
  recognize and display exception frames generated by exceptions that
  do not result in a stack switch, such as general protection faults.
  Without the patch, the backtrace would potentially not display the 
  exception frames because the "error_exit" assembly-code label in 
  entry_64.S was replaced by the error_exit() entry point.
  (anderson at redhat.com)

- The kernel patch for ppc64 CONFIG_SPARSEMEM_VMEMMAP kernels that
  stores vmemmap page mapping information so that the crash utility
  is able to translate vmemmap'd kernel virtual addresses has been
  updated.  The crash utility patch that was (preemptively) applied
  in 5.0.2 for the initial kernel patch needs this update. 
  (anderson at redhat.com)

- Fix the error message for the "dev -p" comand when run on 2.6.26
  or later kernels, which no longer have the global "pci_devices"
  list head.  The patch changes the message to show "dev: -p option
  not supported or applicable on this architecture or kernel", instead
  of the misleading "dev: no PCI devices found on this system" message.
  (anderson at redhat.com)

- If a cpu in an s390 or s390x dumpfile is offline, and the "bt" 
  command receives a backtrace request for the "swapper" task on that
  cpu, the command will display "CPU offline".
  (holzheu at linux.vnet.ibm.com)

- Fix for 2.6.34 and later x86_64 kernels which generate per-cpu 
  symbols of type 'd' or type 'D' instead of type 'V'.  Without the 
  patch, an x86_64 crash session fails during initialization with the 
  error message "crash: cannot determine idle task addresses from 
  init_tasks[] or runqueues[]", followed by "crash: cannot resolve 
  init_task_union".  It is unclear why some kernel builds result in
  only type 'V' per-cpu symbols, whereas others result in in type 'd'
  and 'D', so the patch accepts both.
  (Kashyap.Desai at lsi.com)

- Fix to prevent a segmentation violation during initialization in
  the x86_64_get_active_set() function by verifying that the array
  of current tasks in machdep->machspec->current[] has actually been
  allocated.  Theoretically it should never be NULL, but in the 
  unlikely event that x86_64_per_cpu_init() fails to find the required
  per-cpu symbols, it will return without allocating the array.
  (anderson at redhat.com)

- Fix to support KVM dumpfiles created with "virsh dump" that create
  "cpu" header sections using a QEMU CPU_SAVE_VERSION version greater 
  than the supported version of 9.  Without the patch, the crash
  session fails during initialization with the error message "crash: 
  qemu-load.c:501: cpu_init_load_64: Assertion `version_id >= 4 && 
  version_id <= 9' failed."  The patch now accepts CPU_VERSION_VERSION
  values up to 12.  
  (anderson at redhat.com)

- Fix for x86_64 KVM dumpfiles created with "virsh dump" whose kernels
  have a "_text" virtual address higher than __START_KERNEL_map.
  Without the patch, the physical base address calculation fails,
  making the dumpfile unusable.
  (anderson at redhat.com, pbonzini at redhat.com)

- Implemented a new "map" command that is seen only when running with
  KVM guest dumpfiles created with "virsh dump".  The layout of this
  dumpfile format does not allow the access of system memory in a
  "random-access" manner.  Therefore, during session initialization, a 
  potentially time-consuming dumpfile scan procedure is required to 
  create a physical-memory-to-file-offset memory map for use during the
  session.  The new "map" command allows the user to either append the
  memory map to the end of the dumpfile, or to create a discrete memory
  map file.  In either case, the dumpfile scan will not be required 
  during subsequent sessions.  The command's help page may be seen by 
  entering "crash -h map".
  (anderson at redhat.com)

- Fix for an incorrect calculation of the physical base address of a
  fully-virtualized x86_64 RHEL6 guest kernel running on a RHEL5 Xen 
  host.  Without the patch, the session failed during initialization 
  with the error messages "crash: cannot determine base kernel version"
  and "crash: vmlinux and vmcore do not match!"
  (anderson at redhat.com)

- Fix for the "bt" command on inactive (blocked) tasks on 2.6.33 and
  later x86_64 kernels, which have the "thread_return" symbol removed
  from the embedded "switch_to" macro.  Without the patch, when run on
  blocked tasks, the command would fail with the error message "bt: 
  cannot resolve thread_return".
  (anderson at redhat.com)

- Fix for the "bt" command on 2.6.33 and later x86 kernels, which moved
  the "system_call" assembly function to the .kprobes.text section.
  Without the patch, the command would typically display two invalid
  stack frames, both indicating they were in "ia32_sysenter_target".
  (anderson at redhat.com)

- Fix for a segmentation violation caused by the "extensions/trace.c" 
  extension module, as seen when running the "trace show -c <cpu>" 
  command from that module.
  (laijs at cn.fujitsu.com)

- Implemented a "trace dump -t" command for the "extensions/trace.c"
  extension module.  The module already has a "trace show" command
  to show what events had happened before the system crashed, but it 
  is just 1000 lines of code and it is not as complete as the related
  "trace-cmd report" command from trace-cmd(1).  The new extension
  module command generates a "trace.dat" file, which in turn can be
  used by the "trace-cmd report" option of trace-cmd(1).  So this 
  patch improves both the crash trace command and the trace-cmd(1) 
  as well, which can now handle ftrace even if the kernel crashed. 
  (laijs at cn.fujitsu.com)

Download from: http://people.redhat.com/anderson