valgrind on Android does not listen to vgdb -

on android, running valgrind 3.9.0 --vgdb=yes creates fifo pipe should listen vgdb commands (along pipe reverse direction , piece of shared memory). however, command such vgdb instrumentation on hangs forever.

• this tested on armv7 emulator android 4.0.3 (which reported work on readme.android) , on galaxy note ii android 4.3.1 based cyanogenmod
• valgrind built export hwkind=generic , --with-tmpdir=/data/local/inst; other options according readme.android file
• both devices rooted , running insecure adbd's
• two valgrind builds tested, 1 built ndk-r6 , 1 ndk-r9d. result same on configurations
• both devices able run valgrind neither runs listen vgdb

for reference, valgrind command , output follows:

# ./valgrind -v -v -v --vgdb=yes sleep 1000 ==3640== memcheck, memory error detector ==3640== copyright (c) 2002-2013, , gnu gpl'd, julian seward et al. ==3640== using valgrind-3.9.0 , libvex; rerun -h copyright info ==3640== command: sleep 1000 ==3640==  --3640-- valgrind options: --3640--    -v --3640--    -v --3640--    -v --3640--    --vgdb=yes --3640-- contents of /proc/version: --3640--   linux version 2.6.29-g46b05b2 (vchtchetkine@vc-irv.irv.corp.google.com) (gcc version 4.4.3 (gcc) ) #28 thu nov 17 06:39:36 pst 2011 --3640-- arch , hwcaps: arm, armv7-vfp-neon --3640-- page sizes: 4096, max supported 4096 --3640-- valgrind library directory: /data/local/inst/lib/valgrind --3640-- tt/tc: vg_(init_tt_tc) (startup of code management) --3640-- tt/tc: cache: 6 sectors of 27597024 bytes each = 165582144 total --3640-- tt/tc: table: 6 tables  of 11531696 bytes each = 69190176 total --3640-- tt/tc: table: 65521 entries each = 393126 total entries max occupancy 255528 (65%) --3640-- reading syms /system/xbin/busybox --3640--    svma 0x0000008120, avma 0x0000008120 --3640--    object doesn't have symbol table --3640--    object doesn't have dynamic symbol table --3640-- reading syms /data/local/inst/lib/valgrind/memcheck-arm-linux --3640--    svma 0x0038000000, avma 0x0038000000 --3640--    object doesn't have dynamic symbol table --3640-- scheduler: using generic scheduler lock implementation. --3640-- reading suppressions file: /data/local/inst/lib/valgrind/default.supp ==3640== embedded gdbserver: reading /data/local/inst/vgdb-pipe-from-vgdb-to-3640-by-???-on-??? ==3640== embedded gdbserver: writing   /data/local/inst/vgdb-pipe-to-vgdb-from-3640-by-???-on-??? ==3640== embedded gdbserver: shared mem   /data/local/inst/vgdb-pipe-shared-mem-vgdb-3640-by-???-on-??? ==3640==  ==3640== control process using vgdb (which ==3640== don't want do, unless know you're doing, ==3640== or doing strange experiment): ==3640==   /data/local/inst/lib/valgrind/../../bin/vgdb --pid=3640 ...command... ==3640==  ==3640== debug process using gdb: start gdb ==3640==   /path/to/gdb sleep ==3640== , give gdb following command ==3640==   target remote | /data/local/inst/lib/valgrind/../../bin/vgdb --pid=3640 ==3640== --pid optional if 1 valgrind process running ==3640==  --3640-- tt/tc: initialise sector 0 

the vgdb command (there no output until it's killed):

# ./vgdb instrumentation on ^csyscall failed: interrupted system call error opening /data/local/inst/vgdb-pipe-to-vgdb-from-3640-by-???-on-??? read cmd result pid 

some notes:

• on real device, hostname , user not ??? t0lte , root properly. has nothing issue.

• i'm sure fifo piping works in aforementioned /data/local/inst directory because following works:

in root shell inside /data/local/inst:

# mkfifo examplepipe # echo message > examplepipe ... command exits after pipe read in shell ... # 

in shell:

# cat examplepipe message 

• i'm sure vgdb finding valgrind instance because doesn't report fifo not found error.

• i'm guessing @ point reason vgdb hangs valgrind not listen pipe reason.

• valgrind operation runs expected. callgrind outputs produced etc. since vgdb doesn't work, instrumentation starting/stopping , therefore on-demand profiling not possible.

what may issue?

this known limitation of vgdb on android. vgdb-invoker-ptrace.c should ported on android.

see https://bugs.kde.org/show_bug.cgi?id=338977 more details