Changelog
crash (7.2.8-1ubuntu1) focal; urgency=low
* Merge from Debian unstable. Remaining changes:
- Update the maintainer field for Ubuntu.
- If the "live" autopkgtest fails with a recommendation to try
/proc/kcore instead of the default, attempt that before failing
the test. LP: #1858958.
* Fix test, as if will return 0 when no cases were true.
crash (7.2.8-1) unstable; urgency=medium
* New upstream (Closes: #950544)
* Fix for Linux 5.4-rc1 and later kernels that contain commit
688fcbfc06e4fdfbb7e1d5a942a1460fe6379d2d, titled "mm/vmalloc: modify
struct vmap_area to reduce its size". Without the patch "kmem -v" will
display nothing; other architectures that utilize the vmap_area_list to
determine the base of mapped/vmalloc address space will fail.
* Fix for Linux 5.4-rc1 and later kernels that contain commit/merge
e0703556644a531e50b5dc61b9f6ea83af5f6604, titled "Merge tag 'modules-
for-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
which introduces symbol namespaces. Without the patch, and depending upon
the architecture:
(1) the kernel module symbol list will contain garbage entries
(2) the session fails during session initialization with a dump of
the internal buffer allocation stats followed by the message
"crash: cannot allocate any more memory!"
(3) the session fails during session initialization with a
segmentation violation.
* Fix for the "timer -r" option on Linux 5.4-rc1 and later kernels that
contain commit 511885d7061eda3eb1faf3f57dcc936ff75863f1, titled
"lib/timerqueue: Rely on rbtree semantics for next timer". Without the
patch, the option fails with the following error "timer: invalid structure
member offset: timerqueue_head_next".
* Fix for a "[-Wstringop-truncation]" compiler warning emitted when
symbols.c is built in a Fedora Rawhide environment with gcc-9.0.1 or
later.
* Fix for the "kmem -n" option on Linux-5.4-rc1 and later kernels that
contain commit b6c88d3b9d38f9448e0fcf44847a075ea81d5ca2, titled
"drivers/base/memory.c: don't store end_section_nr in memory blocks".
Without the patch, the command option fails with the error message "kmem:
invalid structure member offset: memory_block_end_section_nr".
* Fix for Linux 4.19.5 and later 4.19-based x86_64 kernels which are NOT
configured with CONFIG_RANDOMIZE_BASE and have backported kernel commit
d52888aa2753e3063a9d3a0c9f72f94aa9809c15, titled "x86/mm: Move LDT remap
out of KASLR region on 5-level paging", which modified the 4-level and
5-level paging PAGE_OFFSET values. Without this patch, the crash session
fails during initialization with the error message "crash: seek error:
kernel virtual address: <address> type: "tss_struct ist array".
* Additional fix for the "kmem -n" option on Linux-5.4-rc1 and later kernels
that contain commit b6c88d3b9d38f9448e0fcf44847a075ea81d5ca2, titled
"drivers/base/memory.c: don't store end_section_nr in memory blocks". The
initial fix only addressed the x86_64 architecture; this incremental patch
addresses the other architectures.
* In the unlikely event that the panic task in a dumpfile cannot be
determined by the normal means, scan the kernel log buffer for panic
keywords, and if found, generate the panic task from the CPU number that
is specified following the panic message.
* Adjust a crash-7.1.8 patch for support of /proc/kcore as the live memory
source in Linux 4.8 and later x86_64 kernels configured with
CONFIG_RANDOMIZE_BASE, which randomizes the unity-mapping PAGE_OFFSET
value. Since the problem only arises before the determination of the
randomized PAGE_OFFSET value, restrict the patch such that it only takes
effect during session initialization.
* Add support for extended numbering support in ELF dumpfiles to handle more
than PN_XNUM (0xffff) program headers. If the real number of program
header table entries is equal to or greater than PN_XNUM, the e_phnum
field of the ELF header is set to PN_XNUM, and the actual number is set in
the sh_info field of the section header at index 0.
* Fix for a "warning: large integer implicitly truncated to unsigned type
[-Woverflow]" compiler message generated on 32-bit architectures as a
result of the "Additional fix for the kmem -n option" patch above.
* Add support for handling openSUSE vmlinux files which will be shipped in
.xz compressed format. Without the patch, only gzip and bzip2 formats are
supported.
* Fix for the determination of the ARM64 page size on Linux 4.4 and earlier
kernels that do not have vmcoreinfo data. Without the patch, the crash
session fails during initialization with the error message "crash: "cannot
determine page size".
* Determine the ARM64 kernel's "vabits_actual" value by reading the new
TCR_EL1.T1SZ vmcoreinfo entry.
* Fix to determine the ARM64 kernel's "vabits_actual" value from the ELF
header of a dumpfile created with the "snap.so" extension module.
* Fix two typos in the examples section of the "help bt" display, which
mistakenly show "bf -f" and "bf -FF" instead of "bt -f" and "bt -FF".
* Similar to ARM64, the X86_64, PPC64 and S390x architectures will use the
exported value of MAX_PHYSMEM_BITS from the vmcoreinfo data as the
preferred method if it is available.
* If an S390X kernel crashes before vmcoreinfo initialization, there is no
way to extract the KASLR offset for such early dumps. In a new S390X
kernel patch, the KASLR offset will be stored in the lowcore memory during
early boot and then overwritten after vmcoreinfo is initialized. This
patch allows crash to identify the KASLR offset that is stored in the
lowcore memory.
* Fix for a crash-7.2.7 regression that determined the value of the ARM64
kernel SECTION_SIZE_BITS by reading the in-kernel configuration data if
there is no VMCOREINFO data available. In that case, without the patch, a
double-free exception may occur.
* Fix for segmentation violation if the gdb_readmem_callback() function gets
called from other than a crash command, such as from an epython command
from the mypkdump.so extension module.
* Fix for the "dis -s" option when running against kernels that have been
configured with CONFIG_RANDOMIZE_BASE=y (KASLR). Without the patch, the
command option indicates that the FILE and LINE numbers are "(unknown)",
and that "source code is not available".
* Fix for newer Xen hypervisors, which fail during initialization with the
error message "crash: cannot resolve init_tss". This is caused by a
change in the Xen hypervisor with commit 78884406256, from
4.12.0-rc5-763-g7888440625. In that patch the tss_struct structure was
renamed to tss64 and the tss_page structure was introduced, which contains
a single tss64. Now tss information is accessible via the symbol
"per_cpu__tss_page".
* When accessing the ARM64 kernel's "crash_notes" array, continue to read
the per-cpu NT_PRSTATUS note contents if an invalid note is encountered.
Without the patch, if an invalid note is found, all other notes were
ignored, and subsequent "bt" attempts on the active tasks would fail.
* When accessing the 32-bit ARM kernel's "crash_notes" array, continue to
read the per-cpu NT_PRSTATUS note contents if an invalid note is
encountered. Without the patch, if an invalid note is found, all other
notes were ignored, and subsequent "bt" attempts on the active tasks would
fail.
* Fix for the "log -a" option. The kernel's sk_buff.len field is a 32-bit
unsigned int, but crash was reading its 32-bit value into a 64-bit
unsigned long stack variable. All extra bits that pre-existed in the
upper 32-bits of the stack variable were passed along as part of a buffer
size request; if the upper 32-bit bits were non-zero, then the command
would fail with a dump of the internal buffer allocation stats followed by
the message "log: cannot allocate any more memory!".
* When determining the ARM64 kernel's "vabits_actual" value by reading the
new TCR_EL1.T1SZ vmcoreinfo entry, display its value during session
initialization only when invoking crash with "-d1" or larger -d debug
value.
* Update copyright to 2020 in crash version output.
* Fix for ARM64 when running against Linux 5.5-rc1 and later kernels that
contain commit b6e43c0e3129ffe87e65c85f20fcbdf0eb86fba0, titled "arm64:
remove __exception annotations". Without the patch, the ARM64 crash
session fails during initialization with the error message "crash: cannot
resolve __exception_text_start".
* Fix for support of ELF format kdump vmcores from S390X KASLR kernels.
Without the patch, the crash session fails during initialization with the
error message "crash: vmlinux and vmcore do not match!".
* Fix for support of S390X standalone dumpfiles and LKCD dumpfiles that were
taken from S390X KASLR kernels.
* Rework the previous patch for support of S390X standalone dumpfiles and
LKCD dumpfiles that were taken from S390X KASLR kernels to avoid calling
an s390x-specific function from generic code.
* Fix for a gcc-10 compilation error. Without the patch, the build of the
crash library fails with a stream of error messages indicating "multiple
definition of 'diskdump_flags'"
crash (7.2.7-1) UNRELEASED; urgency=medium
* Document the "-N", "-g" and "-z" options in the "help" command's help
page.
* Fix for a crash-7.2.6 regression to the "p" command. Without the patch, a
gdb pass-through command construct such as: p ((struct zone
*)0xffff901e3ffda000)->min_slab_pages gets parsed incorrectly, and the "-"
is mistaken for an argument option, and each of the subsequent characters
are marked as an "invalid option".
* Export the get_mount_list() and get_dump_level() functions in defs.h for
use by extension modules.
* Change the gating of a debug message in the do_xarray_dump_cb() function
from CRASHDEBUG(0) to CRASHDEBUG(1). Without the patch, users of the
XArray callback functionality may see messages of the sort "entry has
XARRAY_TAG_MASK bits set: 239ab0024001" without setting a debug number.
* Fix for Linux 5.2 and later x86_64 kernels that contain kernel commit
e6401c13093173aad709a5c6de00cf8d692ee786, titled "x86/irq/64: Split the
IRQ stack into its own". Without the patch, the per-cpu IRQ stack
addresses cannot be determined, and as a result backtraces that utilize an
IRQ stack will fail.
* Fix to allow live system analysis of s390x kernels that have been
configured with CONFIG_RANDOMIZE_BASE=y (KASLR). Without the patch, the
"--kaslr=<offset>" command line option is required.
* Fix for Linux 5.2 and later x86_64 kernels that contain kernel commit
019b17b3ffe48100e52f609ca1c6ed6e5a40cba1, titled "x86/exceptions: Add
structs for exception stacks". Without the patch, the exception stack
sizes cannot be determined, and as a result backtraces that initiate from
an exception stack will fail with error messages indicating "bt: invalid
kernel virtual address: <address> type: stack contents" and then "bt: read
of stack at <address> failed".
* Two fixes for the "sys -c" option, one that significantly shortens the
time consumed by the option, and a second fix that addresses occasional
situations where the file and line number data are not displayed.
* Fix for a signed/unsigned comparison bug in vmcoreinfo_read_string() which
could lead to a segmentation violation in the highly unlikely event of a
zero length or severely truncated VMCOREINFO note.
* Fix for the determination of the ARM64 "kimage_voffset" value in Linux 4.6
and later kernels if an ELF format dumpfile: (1) does not contain its
value in a VMCOREINFO note, and (2) if the kernel image was loaded at a
higher address than the system's physical base address. This may happen,
for example, when analyzing a dynamically-created ramdump-to-ELF dumpfile.
* Fix for Linux 4.16 and later ARM64 kernels that contain kernel commit
fa2a8445b1d3810c52f2a6b3a006456bd1aacb7e, titled "arm64: allow ID map to
be extended to 52 bits", and which have been configured with both
CONFIG_DEVMEM=y and CONFIG_STRICT_DEVMEM=y. Without the patch, an
inconsequential error message indicating "crash: read error: kernel
virtual address: <address> type: idmap_ptrs_per_pgd" is displayed during
initialization.
* Introduction of a new "bt -p" option that generates a backtrace of the
panic task, regardless of the current context. This option is only
applicable when running against dumpfiles in which the panic task is
known.
* When the gdb-7.6.patch file is updated in an existing source tree, it gets
re-applied during the next build using "patch -N --fuzz=0", which ignores
patches that have already been applied. However, if a gdb file has been
modified multiple times, the secondary patching may fail to recognize that
a given patch has been previously applied, and will attempt to re-apply
it. To prevent any uninintended consequences, the gdb-7.6.patch file will
also act as a shell script invoked by the Makefile, which restores any
selected gdb file to its original state prior to all secondary patch
applications.
* As an addendum to the previous patch for updating the gdb-7.6.patch in an
existing pre-built source tree, when rebuilding for the ppc64
architecture, do not restore the selected gdb files. This is because the
gdb-7.6-ppc64le-support.patch will have modified the selected files during
the initial build.
* Extend the "timer" command with a new "TTE" column that displays the
remaining time in jiffies until the expiration of a timer entry, and where
a negative value displays the number of jiffies that have elapsed since a
timer has expired.
* Fix for a "warning: cast to pointer from integer of different size
[-Wint-to-pointer-cast]" compiler message generated by the previous
"timer" patch when compiling kernel.c on 32-bit architectures.
* Fix to the x86_64 "--machdep phys_base=<value>" command line option to
allow the use of a negative decimal number as the value. Without the
patch, only the hexadecimal representation of the value would be accepted.
* Introduction of a new "rd -R" option, which will display memory in reverse
order. Memory will be displayed up to and including the address argument,
which requires that the count argument be greater than 1 in order to
display memory before the specified address.
* Add support for the "count" argument to be used in conjunction with the
"dis -r" and "dis -f" reverse/forward modes of operation. In reverse
mode, the specified "count" number of instructions leading up to and
including the target address will be displayed. In forward mode, the
display will be limited to "count" instructions. Without the patch, using
a count argument in either mode generates a "count argument ignored"
message, and the command proceeds as if it had not been entered.
* Fix a memory leak in the previous "dis" commit.
* Implemented a new "error" environment variable that sets the destination
of error messages. It can be set to either: "default": error messages are
always displayed on the console; if the output of a command is piped to an
external command or redirected to a file, the error messages are also sent
to the pipe or file. "redirect": if the output of a command is piped to
an external command or redirected to a file, error messages are only sent
to the pipe or file; otherwise they are displayed on the console.
"filename": error messages are only sent to the specified filename; they
are not displayed on the console and are not sent to a pipe or file.
* Fix for the "kmem -n" option on Linux 5.3-rc1 and later kernels that
contain commit 326e1b8f83a4318b09033ef754f40c785aed5e68, titled
"mm/sparsemem: introduce a SECTION_IS_EARLY flag". Without the patch,
mem_map addresses containing the flag in bit 3 incorrectly show it as part
of the virtual address; with the patch, the option displays the new "E"
state flag.
* Fix for the "timer" command in RHEL7.6 and later RHEL7 kernels. Without
the patch, the command emits extra faulty timer entries because the
tvec_root.vec[] and tvec.vec[] arrays are tracked using hlist_head
structures where list_head structures should be used.
* crash-7.2.4 commit 6596f1121b added a "list -B" option to allow more
efficient enumeration of longer lists. There is a small bug with this
option where it may incorrectly flag a loop length of "0" on list of
length 1, indicating "list: loop detected, loop length: 0". Since it is
impossible to have a loop of length 0, the erroneous message can be
prevented by ensuring the list count is non-zero.
* Create the specified installation directory if it does not exist. Without
the patch, the Makefile's "make install" target will fail if the
INSTALLDIR and/or DESTDIR macros resolve to a non-existent directory.
* Fix for the internal caching of the kernel's mem_map array of page
structures. Without the patch, in rare circumstances, commands such as
"kmem -p" may erroneously receive zero-filled page structures.
* Fix to prevent a potential segmentation violation when accessing the
compressed configuration data contained in kernels that are configured
with CONFIG_IKCONFIG.
* Determine the ARM64 SECTION_SIZE_BITS value using the following order of
precedence: (1) from the VMCOREINFO data if it exists (2) from the
in-kernel configuration data if it exists (3) the default value
-- Thadeu Lima de Souza Cascardo <email address hidden> Wed, 12 Feb 2020 22:12:51 +0000
