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7.32. crash

Updated crash packages that fix several bugs and add various enhancements are now available for Red Hat Enterprise Linux 6.
The crash packages provide the core analysis suite, which is a self-contained tool that can be used to investigate live systems, as well as kernel core dumps created by the kexec-tools packages or the Red Hat Enterprise Linux kernel.


The crash packages have been upgraded to upstream version 7.1.0, which provides a number of bug fixes and enhancements over the previous version. (BZ#1111357)

Bug Fixes

A prior update of the AMD64 and Intel 64 kernels removed the STACKFAULT exception stack. As a consequence, using the "bt" command with the updated kernels previously displayed an incorrect exception stack name if the backtrace originated in an exception stack other than STACKFAULT. In addition, the "mach" command displayed incorrect names for exception stacks other than STACKFAULT. This update ensures that stack names are generated properly in the described circumstances, and both "bt" and "mach" now display correct information.
Attempting to run the crash utility with the vmcore and vmlinux files previously caused crash to enter an infinite loop and became unresponsive. With this update, the handling of errors when gathering tasks from pid_hash[] chains during session initialization has been enhanced. Now, if a pid_hash[] chain has been corrupted, the patch prevents the initialization sequence from entering an infinite loop. This prevents the described failure of the crash utility from occurring. In addition, the error messages associated with corrupt or invalid pid_hash[] chains have been updated to report the pid_hash[] index number.
On certain system configurations, the "kmem -f", "kmem -F", and "kmem [address]" command options previously took a very long time to complete. This update increases the internal hash queue size used to store the address of each free page, and streamlines the free page search to only check the NUMA node that contains a specified address. As a result, the mentioned "kmem" options no longer have a negative impact on performance.


The makedumpfile command now supports the new sadump format that can represent more than 16 TB of physical memory space. This allows users of makedumpfile to read dump files over 16 TB, generated by sadump on certain upcoming server models.
Users of crash are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.