crash 7.1.4-1ubuntu1 source package in Ubuntu
Changelog
crash (7.1.4-1ubuntu1) xenial; urgency=low * Merge from Debian unstable. Remaining changes: - Build for armhf, arm64, ppc64el. - Minor fixes for live autopkgtest. - debian/tests/live: Redirect gpg stderr to stdout, as that's the only known and expected stderr source. - Simplify ddeb archive requirements. * Dropped patches: - 4_2_support.patch crash (7.1.4-1) unstable; urgency=medium * New upstream version 7.1.4, upstream changelog follows: * Fix for the ARM64 "vtop" command when translating kernel virtual addresses within a 2MB or 512MB huge page in which the PGD or PMD contains software-defined PTE bits. Without the patch, the "PAGE:" address value will show the software-defined bits, the command will not display the related page structure translation, and will end with the message "WARNING: sparsemem: invalid section number: <number>". * Fix for the X86_64 "bt" command in Linux 4.2 and later kernels that are configured with both CONFIG_HAVE_COPY_THREAD_TLS and CONFIG_FRAME_POINTER. Without the patch, the fact that the kernel was compiled with framepointers is not recognized, which may result in backtraces containing stale frame references. * Fix for the "dis" command to support three new x86 instruction extensions that have been added to the Intel instruction set for hardware platforms that support them. The newly-added instructions "clflushopt", "clwb", and "pcommit" prepend 0x66 as a prefix byte to the "clflush", "xsaveopt" and "sfence" instructions respectively. Without the patch: "clflushopt" is disassembled as: "data16" followed by "clflush" "clwb" is disassembled as: "data16" followed by "xsaveopt" "pcommit" is disassembled as: "data16" followed by "sfence" The "clflushopt" instruction was introduced in Linux 3.15 in the clflushopt() function. The "clwb" and "pcommit" instructions were introduced in Linux 4.1 in the clwb() and pcommit_sfence() functions. * Fix for the extensions/trace.c extension module for Linux 4.2 and later kernels. Without the patch, the module fails to load, with the message "failed to init the offset, struct:ftrace_event_call, member:list". * For many years, Xen Dom0 dumps could only be saved in ELF format. Since makedumpfile commit 349a0ed1, it is now possible to save Xen dumps in compressed kdump format. This patch set adds support for these files. Two new files, xen_dom0.c and xen_dom0.h, have been added to provide the common functionality required by both ELF and compressed kdump formats. * Since Linux v4.1, specifically, "MIPS: Rearrange PTE bits into fixed positions.", commit be0c37c985eddc46d0d67543898c086f60460e2e, the MIPS PTE bits are at fixed locations. Since they are macros in the kernel, this patch adds an explicit kernel version check in order to determine and set their values. * Display a machine-type mismatch warning if a little-endian PPC64 compressed kdump created by makedumpfile(8) is used as an argument with a non-PPC64 crash utility binary. Without the patch, the dumpfile is accepted, and the session subsequently fails with a message indicating that that the vmlinux and dumpfile do not match. * Fix for bitmap-handling in SADUMP dumpfiles, which associate each bit in a bitmap with a physical page in the reverse order that is used in kdump-compressed format. The bug had not been detected for a long time because bitmaps in SADUMP formats consist mostly of 0x00 and 0xff excluding a very limited amount of memory space for firmware. * Fix for the behavior of the --zero_excluded option when used with SADUMP dumpfiles. Without the patch, the behavior of --zero_excluded option is the opposite to what is expected: reads of filtered pages return successfully with zero-filled memory, while reads of filtered filtered pages fail when --zero_excluded option has been specified. * Fix for the "kmem -i" command in Linux 2.6.27 and later kernels to prevent the possibility that an arbitrary address may be accessed when calculating the number of total huge pages. Without the patch, the command's "COMMIT LIMIT" and "COMMITTED" values may be invalid. * Added recognition of the new DUMP_DH_EXCLUDED_VMEMMAP flag in the header of compressed kdumps, which is set by the new -e option to the makedumpfile(8) facility. The -e option excludes kernel pages that contain nothing but kernel page structures for pages that are not being included in the dump. If the bit is set in the dumpfile, the crash utility will issue a warning that the dumpfile is known to be incomplete during initialization, just prior to the system banner display. * Fix for the handling of compound pages in Linux 4.4 and later kernels, which contain this kernel commit: commit 1d798ca3f16437c71ff63e36597ff07f9c12e4d6 mm: make compound_head() robust The commit above removes the PG_tail and PG_compound page.flags bits and the page.first_page member, and introduces a page.compound_head member, which is a pointer to the head page and whose bit 0 acts as the tail flag. Without the patch, a SLAB or SLUB warning message that indicates "cannot determine how compound pages are linked" is displayed during initialization, and any command that tracks compound pages will be affected. * Fix for the handling of dynamically-sized task_struct structures in Linux 4.2 and later kernels, which contain these commits: commit 5aaeb5c01c5b6c0be7b7aadbf3ace9f3a4458c3d x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86 commit 0c8c0f03e3a292e031596484275c14cf39c0ab7a x86/fpu, sched: Dynamically allocate 'struct fpu' Without the patch, when running on a filtered kdump dumpfile, it is possible that error messages like this will be seen when gathering the tasks running on a system: "crash: page excluded: kernel virtual address: <task_struct address> type: "fill_task_struct". * Fix for the "kmem -s <address>" command in Linux 3.13 and later kernels configured with CONFIG_SLAB. Without the patch, if the address argument is contained within an object in a tail page of a multi-page slab, the command fails with the message "kmem: address is not allocated in slab subsystem: <address>". Furthermore, in Linux 4.4 and later kernels configured with CONFIG_SLAB, addresses that are contained within an object in a tail page of a multi-page slab will not be marked by their slab cache name by the "rd -S" and "bt -F" commands. * Fix for a segmentation violation when attempting to run live on a a system without the crash.ko memory driver, and whose kernel was configured with CONFIG_STRICT_DEVMEM. Without the patch, if any -d<value> is entered on the command line, the crash session fails during initialization. * Update for the determination of the ARM64 page size for kernels containing this Linux 4.4 commit: commit 9d372c9fab34cd8803141871195141995f85c7f7 arm64: Add page size to the kernel image header Without the patch, the kernel page size is calculated by looking at the size of the "swapper_pg_dir" page directory. With this update, the page size can be determined by checking a flag built into the kernel image header, available in the "_kernel_flags_le" absolute symbol. * Fix for the handling of ARM and ARM64 QEMU-generated ELF dumpfiles and compressed kdump clones. The patch utilizes the NT_PRSTATUS notes in the dumpfile headers instead of reading them from the kernel's "crash_notes", which are not initialized when QEMU generates a dumpfile. Without the patch, these warning messages are displayed during session initialization: WARNING: invalid note (n_type != NT_PRSTATUS) WARNING: cannot retrieve registers for active tasks and running "bt" on an active task causes a segmentation violation. * Update to the previous QEMU-specific patch to handle kdump dumpfiles which have offline cpus, and therefore will not contain associated NT_PRSTATUS notes in the dumpfile header. Without the patch, if there are any offline cpus, a segmentation violation is generated during session initialization. * The s390 stand-alone dump tools may write the kernel memory directly to a block device. When running the crash utility against such a block device, a misleading warning message such as this is displayed: WARNING: /dev/sda1: may be truncated or incomplete PT_LOAD p_offset: 16384 p_filesz: 5497558138880 bytes required: 5497558155264 dumpfile size: 0 With the patch, the warning message above will be replaced by a note using this format: NOTE: /dev/sda1: No dump complete check for block devices * Map CTRL-l to clear the screen while in vi insertion mode. Without the patch, it displays "^L". * Introduced a general-purpose handler to register data structures that the kernel has dynamically downsized from the size indicated by the debuginfo data. At this time, only "kmem_cache" and "task_struct" structures that have been downsized are registered, but others may be added in the future. If a downsized data structure is passed to gdb for display, gdb will request a read of the "full" data structure, which may flow into a memory region that was either filtered by makedumpfile(8), or perhaps into non-existent memory, thereby killing the generating command immediately due to a partial read. With this patch, commands such as "struct" and "task" that reference downsized data structures will have their reads flagged to return successfully if partial read error occurs. * Fix for Linux 3.18 and later 32-bit ARM kernels that are configured with CONFIG_SLAB which contain percpu array_cache structures that were allocated with vmalloc(). Without the patch, during session initialization there will be error messages that indicate "crash: kmem_cache: <vaddr>: invalid array_cache pointer: <vaddr>", and during runtime, the "kmem -[sS]" commands will show kmem_cache lines that marked as "[INVALID/CORRUPTED]". * Added a new "list -l <offset>" option that can only be used in conjunction with "-s", and requires that the "start" address is the address of a list_head, or other similar list linkage structure whose first member points to the next linkage structure. The "-l <offset>" argument is the offset of the embedded list linkage structure in the specified "-s" data structure; it can be either a number of bytes or expressed in "struct.member" format. * Enhanced the debug-only display of the first kernel data items read during session initialization. This includes the system's cpu maps, xtime, and utsname data. These require at least "-d1" as a command line option value, and are primarily useful as an aide for debugging suspect dumpfiles that fail during session initialization. * Added "print_array" as a new internal variable that may be turned on/off with the "set" command. When set to "on", gdb's printing of arrays will be set to "pretty", so that the display of each array element will consume one line. * Introduction of the "sys -i" option, which displays the kernel's DMI identification string data if available. * Fix for "crash --osrelease" on Xen kernels that have both VMCOREINFO and VMCOREINFO_XEN ELF notes. Without the patch, the command returns "(unknown)". crash (7.1.3-1) UNRELEASED; urgency=medium * New upstream version 7.1.3, upstream changelog follows: * Fix for the "crash --osrelease" option for flattened format dumpfiles in the unlikely event that the dumpfile header does not contain the VMCOREINFO note section from the original ELF /proc/vmcore. Without the patch, the command displays nothing instead of showing "unknown". * Fix for the "kmem -s <address>", "bt -F[F]", and "rd -S[S]" options in kernels configured with CONFIG_SLUB. Without the patch, if a referenced slab object address comes from a slab cache that utilizes a multiple-page slab, and the object is located within a tail page of that slab cache, it will not be recognized as a slab object. The "bt -F[F]" and "rd -S[S]" options will just show the object address, and the "kmem -s <address>" object will indicate "kmem: address is not allocated in slab subsystem: <address>". This bug is a regression that was introduced in crash-7.1.0 by commit 8b2cb365d7fb139e77cedd80d4061332099ed382, which addressed a bug where stale slab object addresses were incorrectly being recognized as valid slab objects. * Fix for a segmentation violation generated by the ARM64 "bt -[f|F]" options when analyzing the active tasks in vmcores generated by the kdump facility. This bug is a regression that was introduced in crash-7.1.2 by commit 15a58e4070486efa2aa965bdd636626e62b65cc7, which was an enhancement of the ARM64 backtrace capability for active tasks in kdump vmcores. * Fix for the extensions/trace.c extension module to account for kernels that are not configured with CONFIG_TRACE_MAX_TRACER. Without the patch, the module fails to load with the error message "failed to init the offset, struct: trace_array, member: max_offset". * If a kdump dumpfile is marked as incomplete in its ELF or compressed kdump header, and the user has not used the --zero_excluded command line option, append a note to the incomplete dump WARNING message shown during invocation that suggests the use of --zero_excluded. * Fix for the RSS value displayed by the "ps" command in Linux 2.6.34 and later big-endian machines. Without the patch, a task's RSS value will be erroneously calculated by using twice its file pages instead of adding its file pages with its anonymous pages. * Do not search for a panic task in s390x dumpfiles that are marked as a "live dump" by the "zgetdump" facility. Without the patch, an exhaustive, unnecessary, search of all kernel stacks that looks for evidence of a system crash may find an invalid reference in a task's kernel stack due to the common zero-based user and kernel virtual address space ranges of the s390x, causing the task to be mistakenly set as the "PANIC" task. * Mark the "crash" task that generated a snapshot vmcore utilizing the the "snap.so" extension module as "(ACTIVE)" in the STATE field of the initial system banner and the "set" command. Without the patch, the task's STATE field shows it as the "(PANIC)" task. * Second part of: Do not search for a panic task in s390x dumpfiles that are marked as a "live dump" by the "zgetdump" facility... The first part prevented a search of the active tasks; this part prevents the last-ditch search of all tasks. * When searching all kernel stacks for evidence of a panic task in "live" s390x dumpfiles created by the VMDUMP, stand-alone dump, or "virsh dump" facilities, none of which explicitly mark the dumpfile as a "live dump", run a standard "bt" backtrace on each kernel stack instead of the text-address-only "bt -t". Without the patch, an invalid text reference may be found in a task's kernel stack due to the common zero-based user and kernel virtual address space ranges of the s390x, causing the task to be mistakenly set as the "PANIC" task. * Introduction of the "dis -f <address>" option, which disassembles from the target address until the end of the function. * Fix for the ARM64 "dis" command to prevent branch target addresses from being displayed as kernel system call alias/wrapper names, for example, "SyS_read+<offset>" instead of "sys_read+<offset>". * Fix for the PPC64 "dis" command to prevent conditional branch target addresses from being displayed as kernel system call alias/wrapper names, for example, "SyS_read+<offset>" instead of "sys_read+<offset>". * Fix for the S390X "dis" command to prevent jump target addresses from being displayed as kernel system call alias/wrapper names, for example, "SyS_read+<offset>" instead of "sys_read+<offset>". * Fix for the "dis" command on architectures with variable-length instructions. Without the patch, "dis [-f] <function>" may continue beyond the end of a function, disassembling the memory that is in between the target function and the next function. For kernel module functions, the module's debuginfo data must be loaded. * Minor cleanup and error handling fix-up for the "dis" command. Without the patch, if the target address of "dis -r" or "dis -f" is not an exact address of an instruction, "dis -r" will continue beyond the target address, and "dis -f" will show nothing. * Reduce the unnecessary error messages if a directory is used as a command line argument. Without the patch, six error messages are displayed: crash: unable to read dump file /tmp /tmp: ELF header read: Is a directory /tmp: ELF header read: Is a directory crash: /tmp: read: Is a directory read_maps: unable to read header from /tmp, errno = 1 crash: vmw: Failed to read '/tmp': [Error 21] Is a directory With the patch applied, the functions that generate those messages are not called; only the standard "not a supported file format", and "Usage" messages will be displayed. * If the method of determining how compound pages are linked cannot be accomplished due to page struct related changes in upstream kernels, issue a WARNING message during session initialization. * Fix for the "timer" command on Linux 4.2 and later kernels, which contain this kernel commit that modifies the tvec_root and tvec data structures: commit bc7a34b8b9ebfb0f4b8a35a72a0b134fd6c5ef50 timer: Use hlist for the timer wheel hash buckets Without the patch, the "timer" command will spew messages indicating "timer: invalid list entry: 0", followed by "timer: ignoring faulty timer list at index <number> of timer array". * Introduction of the "dis -s <address>" option, which displays the filename and line number that is associated with the specified text location, followed by a source code listing if it is available on the host machine. The line associated with the text location will be marked with an asterisk; depending upon gdb's internal "listsize" variable, several lines will precede the marked location. If a "count" argument is entered, it specifies the number of source code lines to be displayed after the marked location; otherwise the remaining source code of the containing function will be displayed. * Added a new "--src <directory>" command line option for use by the "dis -s" option if the kernel source code is not located in the standard location that is compiled into the kernel's debuginfo data. The directory argument should point to the top-level directory of the kernel source tree. crash (7.1.2-1) UNRELEASED; urgency=medium * New upstream version 7.1.2, upstream changelog follows: * Enhancement of the ARM64 backtrace capability. Without the patch, backtraces of the active tasks start at the function that is saved in each per-cpu ELF note. With the patch, the backtrace will start at the "crash_kexec" function on the panicking cpu, and at the "crash_save_cpu" function on the other active cpus. By doing so, the backtrace will display the exception handling functions leading to crash_kexec() or crash_save_cpu(), as well as the exception frame register set as it was at the time of the fatal exception on the panic cpu, or when the shutdown IPI was received on the other cpus. * Enabled the "bt -R" option on the ARM64 architecture. Without the patch, the option fails with the message "bt: -R option not supported or applicable on this architecture or kernel". * Enabled the "crash --log vmcore" command line option on the ARM64 architecture. Without the patch, the option fails with the message "crash: crash --log not implemented on ARM64: TBD". * Fix for the S390X "bt" command when running against kernels that have Linux 4.0 commit 2f859d0dad818765117c1cecb24b3bc7f4592074, which removes the "async_stack" and "panic_stack" members from the "pcpu" structure. Without the patch, backtraces of active tasks that were executing I/O or machine check interrupts are not displayed, while other tasks may generate fatal readmem() errors of type "readmem_ul". * Fix to prevent an unnecessary/temporary GETBUF() memory allocation of 1 MB by the dump_mem_map() utility function when the kernel is configured with CONFIG_SPARSEMEM. * Speed up the "crash --osrelease" option when used with "flattened" format dumpfiles. Without the patch, the rearranged data array initialization is performed before the vmcoreinfo data in the header is read, which can take a significant amount of time with large dumpfiles. The patch simply looks for the appropriate vmcoreinfo data string near the beginning of the dumpfile. * Fix for the initialization-time sorting mechanism required for "flattened format" dumpfiles if the dumpfile is truncated/incomplete. Without the patch, the sorting function continues performing invalid reads beyond the of the dumpfile, which may lead to an infinite loop instead of a session-ending error message. In addition, since the sorting operation may take several minutes, a "please wait" message with an incrementing percentage-complete counter will be displayed. * Several fixes associated with the gathering and display of task state. Without the patch: (1) The "ps" command's ST column shows "??" for tasks in the TASK_WAKING state. (2) The "ps" command's ST column shows "??" for tasks in the TASK_PARKED state in Linux 3.14 and later kernels. (3) The STATE field of the initial system banner and the "set" command are incorrect if the task state has the TASK_WAKING, TASK_WAKEKILL modifier, or TASK_PARKED bits set in Linux 3.14 and later kernels. (4) The "foreach DE" task identifier fails if a task with a PID number of 0xDE (222) exists. (5) The "foreach" command's "SW", "PA", "TR" and "DE" task identifiers inadvertently select all tasks in kernel versions that do not have those states. (6) The "help -t" output would display incorrect values for the TASK_WAKEKILL, TASK_WAKING and TASK_PARKED states in Linux 3.14 and later kernels. Lastly, support for the TASK_NOLOAD modifier introduced in Linux 4.2 has been added to STATE field of the "set" command and the initial system banner. * Fix for the internal memory allocation functionality. Without the patch, in the unlikely event where the GETBUF() facility has to utilize malloc() to allocate a buffer, and CTRL-c is entered while that buffer is being zeroed out before being returned to the caller, it may result in a never-ending set of "malloc-free mismatch" error messages. * Fix for the PPC64 "bt" command for active non-panic tasks. Without the patch, the backtrace may fail immediately with the error message "bt: invalid kernel virtual address: f type: Regs NIP value". * Fix for the "bt" command on little-endian PPC64 machines for tasks that are blocked in __schedule(). Without the patch, there will be two "__switch_to" frames displayed before the normal "__schedule" frame that is used as the starting point for blocked tasks. * Fix for the PPC64 "bt" command to align its exception frame verifier function with the most recent version of the kernel's getvecname() function, which was updated in Linux 3.12. Without the patch, the "Hypervisor Decrementer", "Emulation Assist", "Hypervisor Doorbell", "Altivec Unavailable", "Instruction Breakpoint", "Denormalisation", "HMI" and "Altivec Assist" exception types are not recognized and their exception frames not displayed; the "Doorbell" exception type is marked as a "reserved" exception type, * Fix for the "timer" command when run on a kernel with a large number of cpus. Without the patch, the command may fail prematurely with a dump of the internal crash utility allocated buffer statistics followed by the message "timer: cannot allocate any more memory!", * Commit f95ecdc330a11d3701de859aab59a5ab5954aae6, which speeds up "crash --osrelease" for flattened format dumpfiles, inadvertently broke the option for ELF kdump and compressed kdump dumpfiles. * Implementation of two new "files" command options. The "files -c" option is context-sensitive, similar to the the regular "files" command when used without an argument, but replaces the FILE and DENTRY columns with I_MAPPING and NRPAGES columns that reflect each open file's inode.i_mapping address_space structure address, and the address_space.nrpages count within it; this shows how many of each open file's pages are currently in the system's page cache. The "files -p <inode>" option takes the address of an inode, and dumps all of its pages that are currently in the system's page cache, borrowing the "kmem -p" page structure output. * Modified the qualification for the execution of the "runq -g" option. Without the patch, if the target kernel was not configured with both CONFIG_FAIR_GROUP_SCHED and CONFIG_RT_GROUP_SCHED, the command fails with the message "runq: -g option not supported or applicable on this architecture or kernel". With this patch, if the kernel was built with either CONFIG_FAIR_GROUP_SCHED or CONFIG_RT_GROUP_SCHED, the command will execute. * Fix for the error handling of the "foreach task -R struct.member" format if an invalid structure and/or member is used as an argument. Without the patch, the command will display the expected error indicating "task: invalid structure member reference", but then will be followed by a stream of "task: recursive temporary file usage" error messages. * Force the 32-bit MIPS extensions/eppic.so to be compiled with -m32. This is required when "make extensions" is executed after the top level crash binary has been built with "make TARGET=MIPS" on an x86_64 host. * If the starting hexadecimal address of a function is passed to the "dis" command without a count argument, disassemble the entire function -- similar to when a symbol name of a function is passed without a count argument. Without the patch, only one instruction is displayed. * Fix compiler warning generated by extensions/trace.c when compiled with gcc version 5. Without the patch, the message "warning: the use of 'mktemp' is dangerous, better use 'mkstemp'" is generated. * Update the extensions/eppic.mk file to clone the eppic source code from https://github.com/lucchouina/eppic.git. * Export the previously static symbol_name_count() function, which returns a count of symbols with the same name. Export a new is_symbol_text() function, which checks whether specified symbol entry is a type 't' or 'T'. * If a symbol or symbol+offset argument is passed to the "dis" command, and there are multiple text symbols with the same symbol name, then display a message indicating that there are "duplicate text symbols found", followed by a list of the symbols. Without the patch, the duplicate symbol with the lowest virtual address is used. -- Chris J Arges <email address hidden> Tue, 09 Feb 2016 06:08:21 -0600
Upload details
- Uploaded by:
- Chris J Arges
- Uploaded to:
- Xenial
- Original maintainer:
- Ubuntu Developers
- Architectures:
- i386 ia64 alpha powerpc ppc64el amd64 armel armhf arm64 s390x
- Section:
- utils
- Urgency:
- Medium Urgency
See full publishing history Publishing
Series | Published | Component | Section |
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Downloads
File | Size | SHA-256 Checksum |
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crash_7.1.4.orig.tar.gz | 30.6 MiB | 714cb89d40f02ef78539017641573c63eb2e2eb3589d4fac8dc41a2215a37758 |
crash_7.1.4-1ubuntu1.diff.gz | 97.7 KiB | fb1efe5ffa391635339f26400251a5057ac2a8840513be0605753ee4d5834294 |
crash_7.1.4-1ubuntu1.dsc | 1.6 KiB | a86cccc3602a16eec86901c8cb3f70d4d66e8b6eed62a174ee6d2ee0aa0ab203 |
Available diffs
- diff from 7.1.1-1ubuntu5 to 7.1.4-1ubuntu1 (64.4 KiB)
Binary packages built by this source
- crash: kernel debugging utility, allowing gdb like syntax
The core analysis suite is a self-contained tool that can be used to
investigate either live systems, or multiple different core dump formats
including kdump, LKCD, netdump and diskdump.
.
o The tool is loosely based on the SVR4 crash command, but has been
completely integrated with gdb in order to be able to display
formatted kernel data structures, disassemble source code, etc.
.
o The current set of available commands consist of common kernel core
analysis tools such as a context-specific stack traces, source code
disassembly, kernel variable displays, memory display, dumps of
linked-lists, etc. In addition, any gdb command may be entered,
which in turn will be passed onto the gdb module for execution.
.
o There are several commands that delve deeper into specific kernel
subsystems, which also serve as templates for kernel developers
to create new commands for analysis of a specific area of interest.
Adding a new command is a simple affair, and a quick recompile
adds it to the command menu.
.
o The intent is to make the tool independent of Linux version dependencies,
building in recognition of major kernel code changes so as to adapt to
new kernel versions, while maintaining backwards compatibility.
- crash-dbgsym: debug symbols for package crash
The core analysis suite is a self-contained tool that can be used to
investigate either live systems, or multiple different core dump formats
including kdump, LKCD, netdump and diskdump.
.
o The tool is loosely based on the SVR4 crash command, but has been
completely integrated with gdb in order to be able to display
formatted kernel data structures, disassemble source code, etc.
.
o The current set of available commands consist of common kernel core
analysis tools such as a context-specific stack traces, source code
disassembly, kernel variable displays, memory display, dumps of
linked-lists, etc. In addition, any gdb command may be entered,
which in turn will be passed onto the gdb module for execution.
.
o There are several commands that delve deeper into specific kernel
subsystems, which also serve as templates for kernel developers
to create new commands for analysis of a specific area of interest.
Adding a new command is a simple affair, and a quick recompile
adds it to the command menu.
.
o The intent is to make the tool independent of Linux version dependencies,
building in recognition of major kernel code changes so as to adapt to
new kernel versions, while maintaining backwards compatibility.