On 2012-01-06 08:04 +0100, Raphael Geissert wrote:
> On Thursday 05 January 2012 15:36:47 Raphael Geissert wrote:
>> Apparently nobody had run valgrind on the collector for a long time and
>> there are lots of bugs, but those have been there for a long time. Will
>> probably address them by tomorrow and post a patch, so that if you have no
>> luck with the backtrace you can run it on valgrind and get a meaningful
>> output.
How should I proceed to obtain a backtrace? Running readahead-collector
manually does not seem to do anything, and the manpage is rather terse.
> Attached is the patch. The only things that valgrind still complains about
> are
> some leaks[1] and the use of some uninitialized memory in auparse (which I'll
> try to investigate sts.)
>
> To run valgrind do something like:
> touch /.readahead_collect
> edit /etc/init.d/early-readahead to replace s-s-d's
> --exec $READAHEAD_COLLECT_CMD
> with
> --exec /usr/bin/valgrind -- --trace-children=yes --track-origins=yes
> $READAHEAD_COLLECT_CMD 2> /run/rac-valgrind.log
Thanks, that may have produced some meaningful output (attached).
Cheers,
Sven
==240== Memcheck, a memory error detector
==240== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al.
==240== Using Valgrind-3.6.1 and LibVEX; rerun with -h for copyright info
==240== Command: /sbin/readahead-collector
==240==
==240== Warning: ignored attempt to set SIGKILL handler in sigaction();
==240== the SIGKILL signal is uncatchable
==240== Warning: ignored attempt to set SIGSTOP handler in sigaction();
==240== the SIGSTOP signal is uncatchable
==240==
==240== HEAP SUMMARY:
==240== in use at exit: 335 bytes in 23 blocks
==240== total heap usage: 24 allocs, 1 frees, 687 bytes allocated
==240==
==240== LEAK SUMMARY:
==240== definitely lost: 0 bytes in 0 blocks
==240== indirectly lost: 0 bytes in 0 blocks
==240== possibly lost: 0 bytes in 0 blocks
==240== still reachable: 335 bytes in 23 blocks
==240== suppressed: 0 bytes in 0 blocks
==240== Rerun with --leak-check=full to see details of leaked memory
==240==
==240== For counts of detected and suppressed errors, rerun with: -v
==240== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 15 from 6)
==243== Conditional jump or move depends on uninitialised value(s)
==243== at 0x491717D: auparse_init (in /lib/libauparse.so.0.0.0)
==243== by 0x804B75E: parse_events (readahead-collector.c:1035)
==243== by 0x67B3E45: (below main) (libc-start.c:228)
==243== Uninitialised value was created by a heap allocation
==243== at 0x48CC018: malloc (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==243== by 0x804A6FF: main (readahead-collector.c:926)
==243==
==243== Conditional jump or move depends on uninitialised value(s)
==243== at 0x49171C8: auparse_init (in /lib/libauparse.so.0.0.0)
==243== by 0x804B75E: parse_events (readahead-collector.c:1035)
==243== by 0x67B3E45: (below main) (libc-start.c:228)
==243== Uninitialised value was created by a heap allocation
==243== at 0x48CC018: malloc (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==243== by 0x804A6FF: main (readahead-collector.c:926)
==243==
==243== Conditional jump or move depends on uninitialised value(s)
==243== at 0x48CB1DF: free (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==243== by 0x804BDC2: parse_events (readahead-collector.c:1204)
==243== by 0x804A7FB: main (readahead-collector.c:962)
==243== Uninitialised value was created by a stack allocation
==243== at 0x804B704: parse_events (readahead-collector.c:1024)
==243==
==243== Invalid free() / delete / delete[]
==243== at 0x48CB21C: free (in
/usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==243== by 0x804BDC2: parse_events (readahead-collector.c:1204)
==243== by 0x804A7FB: main (readahead-collector.c:962)
==243== Address 0xfe8cba16 is on thread 1's stack
==243==
==243== Invalid read of size 4
==243== at 0x804BDB8: parse_events (readahead-collector.c:1204)
==243== by 0x804A7FB: main (readahead-collector.c:962)
==243== Address 0xfe8ca99c is just below the stack ptr. To suppress, use:
--workaround-gcc296-bugs=yes
==243==
==243==
==243== Process terminating with default action of signal 11 (SIGSEGV)
==243== Access not within mapped region at address 0xFE8C5FFC
==243== at 0x804BDB8: parse_events (readahead-collector.c:1204)
==243== by 0x804A7FB: main (readahead-collector.c:962)
==243== If you believe this happened as a result of a stack
==243== overflow in your program's main thread (unlikely but
==243== possible), you can try to increase the size of the
==243== main thread stack using the --main-stacksize= flag.
==243== The main thread stack size used in this run was 8388608.
==243==
==243== HEAP SUMMARY:
==243== in use at exit: 10,407 bytes in 26 blocks
==243== total heap usage: 177 allocs, 551 frees, 1,062,674 bytes allocated
==243==
==243== LEAK SUMMARY:
==243== definitely lost: 1,040 bytes in 1 blocks
==243== indirectly lost: 0 bytes in 0 blocks
==243== possibly lost: 0 bytes in 0 blocks
==243== still reachable: 9,367 bytes in 25 blocks
==243== suppressed: 0 bytes in 0 blocks
==243== Rerun with --leak-check=full to see details of leaked memory
==243==
==243== For counts of detected and suppressed errors, rerun with: -v
==243== ERROR SUMMARY: 5121 errors from 5 contexts (suppressed: 15 from 6)
