10:05 a.m.
Download from: http://people.redhat.com/anderson
Changelog:
- Implemention of a new "arguments-input-file" feature, where an input
file containing crash command arguments may be iteratively fed to
a crash command. For each line of arguments in an input file, the
selected crash command will be executed. Taking a simple example,
consider an a file named "input" which contains several task_struct
addresses:
crash> cat input
ffff88022bdc2080
ffff88012ae78ac0
ffff88012c334b00
ffff88012c335540
crash>
Each line in the input file may be passed to a crash command by
entering the redirection character followed by the filename:
crash> ps < input
PID PPID CPU TASK ST %MEM VSZ RSS COMM
5752 624 5 ffff88022bdc2080 IN 0.0 12340 2584 udevd
PID PPID CPU TASK ST %MEM VSZ RSS COMM
5779 4927 1 ffff88012ae78ac0 IN 0.0 97820 3916 sshd
PID PPID CPU TASK ST %MEM VSZ RSS COMM
5956 1 3 ffff88012c334b00 IN 0.0 27712 868 auditd
PID PPID CPU TASK ST %MEM VSZ RSS COMM
5784 5779 2 ffff88012c335540 IN 0.0 108392 1856 bash
crash> struct task_struct.pid,mm < input
pid = 5752
mm = 0xffff88022ab65100
pid = 5779
mm = 0xffff88012c272180
pid = 5956
mm = 0xffff88012b00f7c0
pid = 5784
mm = 0xffff88012ae30800
crash>
The input file may contain data containing anything that can be
inserted into a given crash command line. There is no restriction
on the number of arguments in each line; essentially the data in
each input file line will be inserted into the command line starting
where the "<" character is located, and any intervening whitespace
and the filename will be removed. However, because pipes and output
redirection are set up prior to the insertion of input file data,
pipe or redirection should not be put on input file lines. If that
is attempted, the arguments will just be passed to the command, with
unpredictable results. However, output can be piped or redirected
the same way as can be done with normal commands:
crash> set < input | grep -e COMMAND -e CPU
COMMAND: "udevd"
CPU: 5
COMMAND: "sshd"
CPU: 1
COMMAND: "auditd"
CPU: 3
COMMAND: "bash"
CPU: 2
crash>
Many thanks to Josef Bacik for proposing this feature.
(anderson(a)redhat.com)
- Fix for the "runq" command for kernels configured with
CONFIG_FAIR_GROUP_SCHED. Without the patch, it is possible
that a task may be listed twice in a cpu's CFS runqueue.
(d.hatayama(a)jp.fujitsu.com)
- Fix for the internal parse_line() function to properly handle the
case where the first argument in a line is a string argument that is
encapulated with quotation marks.
(anderson(a)redhat.com)
- Fix for the usage of gzip'd vmlinux file that was compressed with
"gzip -n" or "gzip --no-name" without using "-f" on the
command line.
Without the patch, the crash session fails with an error message that
indicates "crash: <string-containing-garbage>: compressed file name
does not start with vmlinux". With the patch, if such a file is used
without "-f", it will be accepted with a message that indicates that
the original filename is unknown, and a suggestion that "-f" be used
to prevent the message.
(anderson(a)redhat.com)
- Added a new "mod -g" option that enhances the symbol display for
kernel modules. After loading a module's debuginfo data, the module
object's section addresses will be shown as pseudo-symbols, like this
simple example using the crash memory driver module:
crash> mod -g -s crash
... [cut] ...
crash> sym -m crash
ffffffff88edb000 MODULE START: crash
ffffffff88edb000 [.text]: section start
ffffffff88edb000 (t) crash_llseek
ffffffff88edb01d (t) crash_read
ffffffff88edb18c [.text]: section end
ffffffff88edb18c [.exit.text]: section start
ffffffff88edb18c (T) cleanup_module
ffffffff88edb18c (t) crash_cleanup_module
ffffffff88edb198 [.exit.text]: section end
ffffffff88edb2a0 [__versions]: section start
ffffffff88edb2a0 (r) ____versions
ffffffff88edb2a0 (r) __versions
ffffffff88edb4a0 [__versions]: section end
ffffffff88edb920 [.data]: section start
ffffffff88edb920 (d) crash_dev
ffffffff88edb960 (d) crash_fops
ffffffff88edba48 [.data]: section end
ffffffff88edba80 [.gnu.linkonce.this_module]: section start
ffffffff88edba80 (D) __this_module
ffffffff88ee3c80 [.gnu.linkonce.this_module]: section end
ffffffff88ee3cc1 MODULE END: crash
crash>
The option may also be used in conjunction with "mod -S".
(nakayama.ts(a)ncos.nec.co.jp)
- Fix for the "gdb" command to prevent the option handling of command
lines. Without the patch, a gdb command string that contained a
"-<character>" pair preceded by whitespace, would fail with the
error message "gdb: gdb: invalid option -- <character>".
(anderson(a)redhat.com)
- Fix for the panic-task determination if a dumpfile is taken on a
system that actually has a cpu count that is equal to its per-arch
NR_CPUS value. Without the patch, the task running on the cpu
whose number is equal to NR_CPUS-1 would be selected.
(d.hatayama(a)jp.fujitsu.com)
- Fix for the x86_64 "bt" command to handle a recursive entry into
the NMI exception stack. While this should normally never happen,
it is possible if, for example, a kprope is entered into a function
that gets executed during NMI handling, and a second NMI is received
after the initial one, corrupting the original exception frame at
the top of the NMI stack. Without the patch, the NMI stack backtrace
and exception frame would be displayed repeatedly; with the patch,
the backtrace and exception frame are followed by the warning message
"NMI exception stack recursion: prior stack location overwritten".
(anderson(a)redhat.com)
- Support dumpfiles that are created by the PPC64 Firmware Assisted
Dump facility, also known as "fadump" or "FAD". Without the patch,
the panic task cannot be determined from a fadump vmcore which was
subsequently compressed with makedumpfile, and therefore a proper
backtrace of the panic task cannot be generated.
(mahesh(a)linux.vnet.ibm.com)
- Preparation for new s390x kernels that will increase MAX_PHYSMEM_BITS
from 42 to 46.
(mahesh(a)linux.vnet.ibm.com, holzheu(a)linux.vnet.ibm.com,
anderson(a)redhat.com)