How to debug a segmentation fault caused by launching the binary on Linux?
No source code is available for the binary.
How to know the system calls made by the binary which caused the seg fault. Is there any debugging utility that might help?
In addition to what's been suggested you can also do the following:
Run ulimit -c unlimited to enable core dumping, then run your app.
At the point of segfaulting it should do a core dump.
Then you can run gdb your_app core and inside gdb run backtrace. Maybe it's been compiled with debugging symbols so you actually get quite a bit of information out.
Does strace your-program help you? It will print a list of all system calls called by your program.
Sample Output
% strace true
.
2 2 [main] true (2064) **********************************************
83 85 [main] true (2064) Program name: C:\cygwin\bin\true.exe (windows pid 2064)
44 129 [main] true (2064) OS version: Windows NT-6.1
36 165 [main] true (2064) **********************************************
145 310 [main] true (2064) sigprocmask: 0 = sigprocmask (0, 0x6123D468, 0x610FBA10)
183 493 [main] true 2064 open_shared: name shared.5, n 5, shared 0x60FF0000 (wanted 0x60FF0000), h 0x70, *m 6
27 520 [main] true 2064 heap_init: heap base 0x20000000, heap top 0x20000000, heap size 0x18000000 (402653184)
30 550 [main] true 2064 open_shared: name foo, n 1, shared 0x60FE0000 (wanted 0x60FE0000), h 0x68, *m 6
18 568 [main] true 2064 user_info::create: opening user shared for 'foo' at 0x60FE0000
17 585 [main] true 2064 user_info::create: user shared version 6467403B
36 621 [main] true 2064 fhandler_pipe::create: name \\.\dir\cygwin-c5e39b7a9d22bafb-2064-sigwait, size 164, mode PIPE_TYPE_MESSAGE
51 672 [main] true 2064 fhandler_pipe::create: pipe read handle 0x84
16 688 [main] true 2064 fhandler_pipe::create: CreateFile: name \\.\dir\cygwin-c5e39b7a9d22bafb-2064-sigwait
35 723 [main] true 2064 fhandler_pipe::create: pipe write handle 0x88
23 746 [main] true 2064 dll_crt0_0: finished dll_crt0_0 initialization
Related
I am a new PocketSphinx user. I just followed the official getting started guide
However, I begin having difficulties when I get to this step:
"To test the installation, run pocketsphinx_continuous -inmic yes and check that it recognizes words you speak into your microphone."
I've attached my terminal output that I receive when I type this command, which ultimately results in 'Segmentation fault: 11'
Any help would be greatly appreciated.
Thanks,
Nakul
nakul : ~ 101 $ pocketsphinx_continuous -inmic yes
INFO: pocketsphinx.c(152): Parsed model-specific feature parameters from /usr/local/share/pocketsphinx/model/en-us/en-us/feat.params
Current configuration:
[NAME] [DEFLT] [VALUE]
-agc none none
-agcthresh 2.0 2.000000e+00
-allphone
-allphone_ci no no
-alpha 0.97 9.700000e-01
-ascale 20.0 2.000000e+01
-aw 1 1
-backtrace no no
-beam 1e-48 1.000000e-48
-bestpath yes yes
-bestpathlw 9.5 9.500000e+00
-ceplen 13 13
-cmn live batch
-cmninit 40,3,-1 41.00,-5.29,-0.12,5.09,2.48,-4.07,-1.37,-1.78,-5.08,-2.05,-6.45,-1.42,1.17
-compallsen no no
-debug 0
-dict /usr/local/share/pocketsphinx/model/en-us/cmudict-en-us.dict
-dictcase no no
-dither no no
-doublebw no no
-ds 1 1
-fdict
-feat 1s_c_d_dd 1s_c_d_dd
-featparams
-fillprob 1e-8 1.000000e-08
-frate 100 100
-fsg
-fsgusealtpron yes yes
-fsgusefiller yes yes
-fwdflat yes yes
-fwdflatbeam 1e-64 1.000000e-64
-fwdflatefwid 4 4
-fwdflatlw 8.5 8.500000e+00
-fwdflatsfwin 25 25
-fwdflatwbeam 7e-29 7.000000e-29
-fwdtree yes yes
-hmm /usr/local/share/pocketsphinx/model/en-us/en-us
-input_endian little little
-jsgf
-keyphrase
-kws
-kws_delay 10 10
-kws_plp 1e-1 1.000000e-01
-kws_threshold 1 1.000000e+00
-latsize 5000 5000
-lda
-ldadim 0 0
-lifter 0 22
-lm /usr/local/share/pocketsphinx/model/en-us/en-us.lm.bin
-lmctl
-lmname
-logbase 1.0001 1.000100e+00
-logfn
-logspec no no
-lowerf 133.33334 1.300000e+02
-lpbeam 1e-40 1.000000e-40
-lponlybeam 7e-29 7.000000e-29
-lw 6.5 6.500000e+00
-maxhmmpf 30000 30000
-maxwpf -1 -1
-mdef
-mean
-mfclogdir
-min_endfr 0 0
-mixw
-mixwfloor 0.0000001 1.000000e-07
-mllr
-mmap yes yes
-ncep 13 13
-nfft 512 512
-nfilt 40 25
-nwpen 1.0 1.000000e+00
-pbeam 1e-48 1.000000e-48
-pip 1.0 1.000000e+00
-pl_beam 1e-10 1.000000e-10
-pl_pbeam 1e-10 1.000000e-10
-pl_pip 1.0 1.000000e+00
-pl_weight 3.0 3.000000e+00
-pl_window 5 5
-rawlogdir
-remove_dc no no
-remove_noise yes yes
-remove_silence yes yes
-round_filters yes yes
-samprate 16000 1.600000e+04
-seed -1 -1
-sendump
-senlogdir
-senmgau
-silprob 0.005 5.000000e-03
-smoothspec no no
-svspec 0-12/13-25/26-38
-tmat
-tmatfloor 0.0001 1.000000e-04
-topn 4 4
-topn_beam 0 0
-toprule
-transform legacy dct
-unit_area yes yes
-upperf 6855.4976 6.800000e+03
-uw 1.0 1.000000e+00
-vad_postspeech 50 50
-vad_prespeech 20 20
-vad_startspeech 10 10
-vad_threshold 2.0 2.000000e+00
-var
-varfloor 0.0001 1.000000e-04
-varnorm no no
-verbose no no
-warp_params
-warp_type inverse_linear inverse_linear
-wbeam 7e-29 7.000000e-29
-wip 0.65 6.500000e-01
-wlen 0.025625 2.562500e-02
INFO: feat.c(715): Initializing feature stream to type: '1s_c_d_dd', ceplen=13, CMN='batch', VARNORM='no', AGC='none'
INFO: acmod.c(162): Using subvector specification 0-12/13-25/26-38
INFO: mdef.c(518): Reading model definition: /usr/local/share/pocketsphinx/model/en-us/en-us/mdef
INFO: mdef.c(531): Found byte-order mark BMDF, assuming this is a binary mdef file
INFO: bin_mdef.c(336): Reading binary model definition: /usr/local/share/pocketsphinx/model/en-us/en-us/mdef
INFO: bin_mdef.c(516): 42 CI-phone, 137053 CD-phone, 3 emitstate/phone, 126 CI-sen, 5126 Sen, 29324 Sen-Seq
INFO: tmat.c(149): Reading HMM transition probability matrices: /usr/local/share/pocketsphinx/model/en-us/en-us/transition_matrices
INFO: acmod.c(113): Attempting to use PTM computation module
INFO: ms_gauden.c(127): Reading mixture gaussian parameter: /usr/local/share/pocketsphinx/model/en-us/en-us/means
INFO: ms_gauden.c(242): 42 codebook, 3 feature, size:
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(127): Reading mixture gaussian parameter: /usr/local/share/pocketsphinx/model/en-us/en-us/variances
INFO: ms_gauden.c(242): 42 codebook, 3 feature, size:
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(244): 128x13
INFO: ms_gauden.c(304): 222 variance values floored
INFO: ptm_mgau.c(476): Loading senones from dump file /usr/local/share/pocketsphinx/model/en-us/en-us/sendump
INFO: ptm_mgau.c(500): BEGIN FILE FORMAT DESCRIPTION
INFO: ptm_mgau.c(563): Rows: 128, Columns: 5126
INFO: ptm_mgau.c(595): Using memory-mapped I/O for senones
INFO: ptm_mgau.c(838): Maximum top-N: 4
INFO: phone_loop_search.c(114): State beam -225 Phone exit beam -225 Insertion penalty 0
INFO: dict.c(320): Allocating 138824 * 32 bytes (4338 KiB) for word entries
INFO: dict.c(333): Reading main dictionary: /usr/local/share/pocketsphinx/model/en-us/cmudict-en-us.dict
INFO: dict.c(213): Dictionary size 134723, allocated 1016 KiB for strings, 1679 KiB for phones
INFO: dict.c(336): 134723 words read
INFO: dict.c(358): Reading filler dictionary: /usr/local/share/pocketsphinx/model/en-us/en-us/noisedict
INFO: dict.c(213): Dictionary size 134728, allocated 0 KiB for strings, 0 KiB for phones
INFO: dict.c(361): 5 words read
INFO: dict2pid.c(396): Building PID tables for dictionary
INFO: dict2pid.c(406): Allocating 42^3 * 2 bytes (144 KiB) for word-initial triphones
INFO: dict2pid.c(132): Allocated 42672 bytes (41 KiB) for word-final triphones
INFO: dict2pid.c(196): Allocated 42672 bytes (41 KiB) for single-phone word triphones
INFO: ngram_model_trie.c(354): Trying to read LM in trie binary format
INFO: ngram_search_fwdtree.c(74): Initializing search tree
INFO: ngram_search_fwdtree.c(101): 791 unique initial diphones
INFO: ngram_search_fwdtree.c(186): Creating search channels
INFO: ngram_search_fwdtree.c(323): Max nonroot chan increased to 152609
INFO: ngram_search_fwdtree.c(333): Created 723 root, 152481 non-root channels, 53 single-phone words
INFO: ngram_search_fwdflat.c(157): fwdflat: min_ef_width = 4, max_sf_win = 25
INFO: continuous.c(307): pocketsphinx_continuous COMPILED ON: Sep 6 2018, AT: 19:28:29
INFO: continuous.c(252): Ready....
Segmentation fault: 11
nakul : ~ 102 $ defaults write com.apple.finder AppleShowAllFiles YES.
I'm serving CakePHP 3.x based sites off a Network Load Balanced (NLB) IIS 10 cluster. The php files reside on an external DFS share. When run with debug enabled, CakePHP throws the following error:
2017-08-16 13:45:39 Error: Fixture creation for "requests" failed "SQLSTATE[HY000]: General error: 10 disk I/O error"
2017-08-16 13:45:39 Warning: Warning (512): Fixture creation for "requests" failed "SQLSTATE[HY000]: General error: 10 disk I/O error" in [\\MY.DOMAIN.COM\WEBAPPS\Sites\some_site\vendor\cakephp\cakephp\src\TestSuite\Fixture\TestFixture.php, line 306]
Request URL: /
Client IP: 10.1.2.250
Trace:
Cake\Error\BaseErrorHandler::handleError() - CORE\src\Error\BaseErrorHandler.php, line 146
Cake\TestSuite\Fixture\TestFixture::create() - CORE\src\TestSuite\Fixture\TestFixture.php, line 306
DebugKit\Model\Table\RequestsTable::ensureTables() - ROOT\vendor\cakephp\debug_kit\src\Model\Table\LazyTableTrait.php, line 56
DebugKit\Model\Table\RequestsTable::initialize() - ROOT\vendor\cakephp\debug_kit\src\Model\Table\RequestsTable.php, line 52
Cake\ORM\Table::__construct() - CORE\src\ORM\Table.php, line 290
Cake\ORM\Locator\TableLocator::_create() - CORE\src\ORM\Locator\TableLocator.php, line 212
Cake\ORM\Locator\TableLocator::get() - CORE\src\ORM\Locator\TableLocator.php, line 179
Cake\ORM\TableRegistry::get() - CORE\src\ORM\TableRegistry.php, line 110
DebugKit\ToolbarService::saveData() - ROOT\vendor\cakephp\debug_kit\src\ToolbarService.php, line 172
DebugKit\Routing\Filter\DebugBarFilter::afterDispatch() - ROOT\vendor\cakephp\debug_kit\src\Routing\Filter\DebugBarFilter.php, line 139
Cake\Event\EventManager::_callListener() - CORE\src\Event\EventManager.php, line 426
Cake\Event\EventManager::dispatch() - CORE\src\Event\EventManager.php, line 391
Cake\Http\ActionDispatcher::dispatchEvent() - CORE\src\Event\EventDispatcherTrait.php, line 78
Cake\Http\ActionDispatcher::dispatch() - CORE\src\Http\ActionDispatcher.php, line 100
Cake\Http\BaseApplication::__invoke() - CORE\src\Http\BaseApplication.php, line 83
Cake\Http\Runner::__invoke() - CORE\src\Http\Runner.php, line 65
Cake\Routing\Middleware\RoutingMiddleware::__invoke() - CORE\src\Routing\Middleware\RoutingMiddleware.php, line 62
Cake\Http\Runner::__invoke() - CORE\src\Http\Runner.php, line 65
Cake\Routing\Middleware\AssetMiddleware::__invoke() - CORE\src\Routing\Middleware\AssetMiddleware.php, line 88
Cake\Http\Runner::__invoke() - CORE\src\Http\Runner.php, line 65
AssetCompress\Middleware\AssetCompressMiddleware::__invoke() - ROOT\vendor\markstory\asset_compress\src\Middleware\AssetCompressMiddleware.php, line 56
Cake\Http\Runner::__invoke() - CORE\src\Http\Runner.php, line 65
Cake\Error\Middleware\ErrorHandlerMiddleware::__invoke() - CORE\src\Error\Middleware\ErrorHandlerMiddleware.php, line 81
Cake\Http\Runner::__invoke() - CORE\src\Http\Runner.php, line 65
Cake\Http\Runner::run() - CORE\src\Http\Runner.php, line 51
Cake\Http\Server::run() - CORE\src\Http\Server.php, line 90
require - ROOT\webroot\index.php, line 37
[main] - ROOT\index.php, line 16
IIS has full write permission to the project root folder (on the network share). The fact that CakePHP error log has captured the above info. proves it. So this is definitely not about file / folder permissions.
What's could be the cause of this error and how to fix?
Thank you.
We have a project written in ANSI C. Generally the memory consumption was not a big concern, but now we have a request to fit our program into 256 KB of RAM. I don't have this exact platform on hands, so I compile my project under 32 bit x86 Linux (because it provides enough different tools to evaluate the memory consumption), optimize what I can, remove some features and eventually I have to have the conclusion: what features we need to sacrifice to be able to run on very small systems (if we're able at all). First of all I did a research what exactly a memory size in linux and it seems I have to optimize the RSS size, not VSZ. But in linux even a smallest program which prints "Hello world!" once a second consumes 285-320 KB in RSS:
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
unsigned char cuStopCycle = 0;
void SigIntHandler(int signo)
{
printf("SIGINT received, terminating the program\n");
cuStopCycle = 1;
}
int main()
{
signal( SIGINT, SigIntHandler);
while(!cuStopCycle)
{
printf("Hello, World!\n");
sleep(1);
}
printf("Exiting...\n");
}
user#Ubuntu12-vm:~/tmp/prog_size$ size ./prog_size
text data bss dec hex filename
1456 272 12 1740 6cc ./prog_size
root#Ubuntu12-vm:/home/app# ps -C prog_size -o pid,rss,vsz,args
PID RSS VSZ COMMAND
22348 316 2120 ./prog_size
Obviously this program will perfectly run on small PLCs, with 64KB of RAM. It is just linux loads a lot of libs. I generate a map file for this program and all this data + bss comes from the CRT library. I need to mention that if I add some code to this project - 10,000 times "a = a + b" or manipulate arrays 2000 long int variables, I see the difference in code size, bss size but eventually the RSS size of the process is the same, it doesn't affected)
So I take this as a baseline, the point I want to reach (and which I will never reach, because I need more functions than just print a message once a second).
So here comes my project, where I removed all extra features, removed all auxiliary functions, removed everything except the basic functionality. There are some ways to optimize more, but not that much, what could be removed is already taken away:
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt/Cmds# ls -l App
-rwxr-xr-x 1 root root 42520 Jul 13 18:33 App
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt/Cmds# size ./App
text data bss dec hex filename
37027 404 736 38167 9517 ./App
So I have ~36KB of code and ~1KB of data. I do not call malloc inside of my project, I use a shared memory allocation with a wrapper library so I can control how much memory is allocated:
The total memory size allocated is 2052 bytes
Under the hood there are malloc calls obviously, if I substitute 'malloc' calls with my function which summarize all alloc requests I see that ~2.3KB of memory is allocated:
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt/Cmds# LD_PRELOAD=./override_malloc.so ./App
Malloc allocates 2464 bytes total
Now I run my project amd see that it consumes 600KB of RAM.
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt# ps -C App -o pid,rss,vsz,args
PID RSS VSZ COMMAND
22093 604 2340 ./App
I do not understand why it eats so much memory. The code size is small. There is not much memory allocated. The size of data is small. Why it takes so much memory? I tried to analyze the mapping of the process:
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt# pmap -x 22093
22093: ./App
Address Kbytes RSS Dirty Mode Mapping
08048000 0 28 0 r-x-- App
08052000 0 4 4 r---- App
08053000 0 4 4 rw--- App
09e6a000 0 4 4 rw--- [ anon ]
b7553000 0 4 4 rw--- [ anon ]
b7554000 0 48 0 r-x-- libpthread-2.15.so
b756b000 0 4 4 r---- libpthread-2.15.so
b756c000 0 4 4 rw--- libpthread-2.15.so
b756d000 0 8 8 rw--- [ anon ]
b7570000 0 300 0 r-x-- libc-2.15.so
b7714000 0 8 8 r---- libc-2.15.so
b7716000 0 4 4 rw--- libc-2.15.so
b7717000 0 12 12 rw--- [ anon ]
b771a000 0 16 0 r-x-- librt-2.15.so
b7721000 0 4 4 r---- librt-2.15.so
b7722000 0 4 4 rw--- librt-2.15.so
b7731000 0 4 4 rw-s- [ shmid=0x70000c ]
b7732000 0 4 4 rw-s- [ shmid=0x6f800b ]
b7733000 0 4 4 rw-s- [ shmid=0x6f000a ]
b7734000 0 4 4 rw-s- [ shmid=0x6e8009 ]
b7735000 0 12 12 rw--- [ anon ]
b7738000 0 4 0 r-x-- [ anon ]
b7739000 0 104 0 r-x-- ld-2.15.so
b7759000 0 4 4 r---- ld-2.15.so
b775a000 0 4 4 rw--- ld-2.15.so
bfb41000 0 12 12 rw--- [ stack ]
-------- ------- ------- ------- -------
total kB 2336 - - -
And it looks like the program size (in RSS) is only 28KB, the rest is consumed by shared libraries. BTW I do not use posix threads, I do not explicitly link to it, but somehow the linker anyway links this library I have no idea why (this is not really important). If we look at the mapping in more details:
root#Ubuntu12-vm:/home/app/workspace/proj_sizeopt# cat /proc/22093/smaps
08048000-08052000 r-xp 00000000 08:01 344838 /home/app/workspace/proj_sizeopt/Cmds/App
Size: 40 kB
Rss: 28 kB
Pss: 28 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 28 kB
Private_Dirty: 0 kB
Referenced: 28 kB
Anonymous: 0 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
...
09e6a000-09e8b000 rw-p 00000000 00:00 0 [heap]
Size: 132 kB
Rss: 4 kB
Pss: 4 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 4 kB
Referenced: 4 kB
Anonymous: 4 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
...
b7570000-b7714000 r-xp 00000000 08:01 34450 /lib/i386-linux-gnu/libc-2.15.so
Size: 1680 kB
Rss: 300 kB
Pss: 7 kB
Shared_Clean: 300 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 300 kB
Anonymous: 0 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
...
b7739000-b7759000 r-xp 00000000 08:01 33401 /lib/i386-linux-gnu/ld-2.15.so
Size: 128 kB
Rss: 104 kB
Pss: 3 kB
Shared_Clean: 104 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 104 kB
Anonymous: 0 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
...
bfb41000-bfb62000 rw-p 00000000 00:00 0 [stack]
Size: 136 kB
Rss: 12 kB
Pss: 12 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 12 kB
Referenced: 12 kB
Anonymous: 12 kB
AnonHugePages: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
So I see that RSS size for my project is 40KB, but only 28 KB is used. Does it mean that this project will fit into 256 KB of RAM?
The heap size is 132KB but only 4 KB is used. Why is that? I'm sure it will be different on the small embedded platform.
The stack is 136KB but only 12KB is used.
GLIBC/LD obviously consume some memory, but what exactly memory will it be on the embedded platform?
I do not look at PSS because it doesn't make any sense in my case, I look only at RSS.
What conclusions can I draw from this picture? How exactly to evaluate memory consumption by the application? Look at the RSS size of the process? Or subtract from this size RSS of all mapped system libraries? What is about heap/stack size?
I would be very grateful for any advises, notes, memory consumption optimizations techniques, DOs and DON'Ts for platforms with extremely small amount of RAM (except obvious - keep amount of data and code to the very minimum).
I also will appreciate an explanation WHY the program with small amount of code and data (and which doesn't allocate much memory) still consumes a lot of RAM in RSS.
Thank you in advance
... fit our program into 256 KB of RAM. I don't have this exact platform on hands, so I compile my project under 32 bit x86 Linux..
And what you now see is that the Linux platform tools make reasonable assumptions of your possible need of stack and heap, given that it nows you run on a big machine, and links-in a reasonable set of library functions for your needs. Some you won't need, but it gives them to you "for free".
To fit in 256 Kb on your target platform, you must compile for your target platform and link with the target platform's libraries (and CRT) using the target platform's linker.
Those will make different assumptions, use possibly smaller linbrary footprints, make smaller assumptions on stack and heap space, etcetera. For example, create "Hello World" for the target platform and check its needs on that target platform. Or use a realistic simulator of the target platform and libraries (and not to forget, OS, whch partly dictates what the libraries must do).
And if it is then still too big, you have to re-write or tweak the whole CRT and all libraries....
the program needs to be compiled/linked with the embedded device in mind.
For best results use a makefile
use the 'rt' library written for the embedded device
use the start.s file, located, via the makefile, where execution begins.
use 'static' in the linker parameters
use the linker parameters to not include any libraries but what is specifically requested.
do not use libraries written for your development machine. Only use libraries written for the embedded device.
do NOT include stdio.h, etc. unless specifically written for the embedded device
do NOT call printf() inside a signal handler.
if possible, do not call printf() at all.
instead write a small char output function and have it perform the output through the uart.
do not use signals, instead use interrupts
the resulting application will not run on your PC., but, once loaded, will run on the 256k device
do not call sleep(), rather write your own function that uses a device timer peripheral, that sets the timer and puts the device into powerdown mode.
the time interrupt needs to bring the device out of the powerdown mode.
in the makefile, specifically set the size of the stack, heap, etc.
have the link step output a .map file. study that map file until you understand everything in it.
use a compiler/linker that is specific for the embedded device
you probably will need to include a function that initializes the peripherals on the device, like the clock, the uart, the timer, the watchdog, and any other built in peripherals that the code actually uses.
you will need a file that allocates the interrupt table, and a small function to handle each of the interrupts, even though most of those functions will do nothing beyond clearing the appropriate interrupt pending flag and returning from the interrupt
you will probably need a function to periodically refresh the watchdog, conditionally, depending on an indication that the main function is still cycling regularily. I.E the main function loop and the initialization function will refresh the watchdog
Background
Code to support a 'panic_action' was recently added to the FreeRADIUS v3.0.x, v2.0.x and master branches.
When radiusd (main FreeRADIUS process) receives a fatal signal (SIGFPE, SIGABRT, SIGSEGV etc...), the signal handler executes a predefined 'panic_action' which is a snippet of shell code passed to system(). The signal handler performs basic substitution for %e and %p writing in the values of the current binary name, and the current PID.
This should in theory allow a debugger like gdb or lldb to attach to the process (panic_action = lldb -f %e -p %p), either to perform interactive debugging, or to automate collection of a backtrace. This actually works well on my system OSX 10.9.2 with lldb, but only for SIGABRT.
Problem
This doesn't seem to work for other signals like SIGSEGV. The mini backtrace from execinfo is valid, but when lldb or gdb attach to the process, they only get the backtrace from for the signal handler.
There doesn't seem to be a way in lldb to switch to an arbitrary frame address.
Does anyone know if there's any way of forcing the signal handler to execute in the same stack as the the thread that received the signal? Or why when lldb attaches the backtraces don't show the full stack.
The actual output looks like:
FATAL SIGNAL: Segmentation fault: 11
Backtrace of last 12 frames:
0 libfreeradius-radius.dylib 0x000000010cf1f00f fr_fault + 127
1 libsystem_platform.dylib 0x00007fff8b03e5aa _sigtramp + 26
2 radiusd 0x000000010ce7617f do_compile_modsingle + 3103
3 libfreeradius-server.dylib 0x000000010cef3780 fr_condition_walk + 48
4 radiusd 0x000000010ce7710f modcall_pass2 + 191
5 radiusd 0x000000010ce7713f modcall_pass2 + 239
6 radiusd 0x000000010ce7078d virtual_servers_load + 685
7 radiusd 0x000000010ce71df1 setup_modules + 1633
8 radiusd 0x000000010ce6daae read_mainconfig + 2526
9 radiusd 0x000000010ce78fe6 main + 1798
10 libdyld.dylib 0x00007fff8580a5fd start + 1
11 ??? 0x0000000000000002 0x0 + 2
Calling: lldb -f /usr/local/freeradius/sbin/radiusd -p 1397
Current executable set to '/usr/local/freeradius/sbin/radiusd' (x86_64).
Attaching to process with:
process attach -p 1397
Process 1397 stopped
(lldb) bt
error: libfreeradius-radius.dylib debug map object file '/Users/arr2036/Documents/Repositories/freeradius-server-fork/build/objs//Users/arr2036/Documents/Repositories/freeradius-server-master/src/lib/debug.o' has changed (actual time is 0x530f3d21, debug map time is 0x530f37a5) since this executable was linked, file will be ignored
* thread #1: tid = 0x8d824, 0x00007fff867fee38 libsystem_kernel.dylib`wait4 + 8, queue = 'com.apple.main-thread, stop reason = signal SIGSTOP
frame #0: 0x00007fff867fee38 libsystem_kernel.dylib`wait4 + 8
frame #1: 0x00007fff82869090 libsystem_c.dylib`system + 425
frame #2: 0x000000010cf1f2e1 libfreeradius-radius.dylib`fr_fault + 849
frame #3: 0x00007fff8b03e5aa libsystem_platform.dylib`_sigtramp + 26
(lldb)
Code
The relevant code for fr_fault() is here:https://github.com/FreeRADIUS/freeradius-server/blob/b7ec8c37c7204accbce4be4de5013397ab662ea3/src/lib/debug.c#L227
and fr_set_signal() the function used to setup signal handlers is here: https://github.com/FreeRADIUS/freeradius-server/blob/0cf0e88704228e8eac2948086e2ba2f4d17a5171/src/lib/misc.c#L61
As the links contain commit hashes the code should be static
EDIT
Finally with version lldb-330.0.48 on OSX 10.10.4 lldb can now go past _sigtram.
frame #2: 0x000000010b96c5f7 libfreeradius-radius.dylib`fr_fault(sig=11) + 983 at debug.c:735
732 FR_FAULT_LOG("Temporarily setting PR_DUMPABLE to 1");
733 }
734
-> 735 code = system(cmd);
736
737 /*
738 * We only want to error out here, if dumpable was originally disabled
(lldb)
frame #3: 0x00007fff8df77f1a libsystem_platform.dylib`_sigtramp + 26
libsystem_platform.dylib`_sigtramp:
0x7fff8df77f1a <+26>: decl -0x16f33a50(%rip)
0x7fff8df77f20 <+32>: movq %rbx, %rdi
0x7fff8df77f23 <+35>: movl $0x1e, %esi
0x7fff8df77f28 <+40>: callq 0x7fff8df794d8 ; symbol stub for: __sigreturn
(lldb)
frame #4: 0x000000010bccb027 rlm_json.dylib`_json_map_proc_get_value(ctx=0x00007ffefa62dbe0, out=0x00007fff543534b8, request=0x00007ffefa62da30, map=0x00007ffefa62aaf0, uctx=0x00007fff54353688) + 391 at rlm_json.c:191
188 }
189 vp = map->op;
190
-> 191 if (value_data_steal(vp, &vp->data, vp->da->type, value) < 0) {
192 REDEBUG("Copying data to attribute failed: %s", fr_strerror());
193 talloc_free(vp);
194 goto error;
This is a bug in lldb related to backtracing through _sigtramp, the asynchronous signal handler in user processes. Unfortunately I can't suggest a workaround for this problem. It has been fixed in the top of tree sources for lldb at http://lldb.llvm.org/ if you're willing to build from source (see the "Source" and "Build" sidebars). But Xcode 5.0 and the next dot release are going to have real problems backtracing past _sigtramp.
I have a SAM9 based board running embedded linux.
I had a JFFS2 file system and now thinking of moving to UBIFS.
I enabled UBIFS as target file system in make menuconfig of buildroot package which I'm using for my board.
I generated the rootfs.arm.ubifs file which I flashed on my board using nandwrite utility of bootloader the same way which I was using for .jffs2 file.
I also changed the bootargs to :
setenv bootargs 'console=ttyS0,115200 rw ubi.mtd=1,2048 rootfstype=ubifs root=ubi0:rootfs'
But I'm getting the following error which booting the board :
Creating 2 MTD partitions on "atmel_nand":
0x000000000000-0x000000400000 : "Kernel"
0x000000400000-0x000010000000 : "Data"
UBI: attaching mtd1 to ubi0
UBI: physical eraseblock size: 131072 bytes (128 KiB)
UBI: logical eraseblock size: 126976 bytes
UBI: smallest flash I/O unit: 2048
UBI: sub-page size: 512
UBI: VID header offset: 2048 (aligned 2048)
UBI: data offset: 4096
UBI warning: ubi_scan: 276 PEBs are corrupted
corrupted PEBs are: 0 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 517
UBI error: ubi_read_volume_table: the layout volume was not found
UBI error: ubi_init: cannot attach mtd1
UBI error: ubi_init: UBI error: cannot initialize UBI, error -22
This is a guess, but did you ubinize your rootfs before flashing it onto the raw NAND?
From http://www.linux-mtd.infradead.org/doc/ubifs.html#L_usptools
The images produced by mkfs.ubifs may be written to UBI volumes using
ubiupdatevol or may be further fed to the ubinize tool to create an UBI
image which may be put to the raw flash.