MavenCentral download problem and JVM crashing
Boronyak opened this issue · 25 comments
Hi!
I am currently using your library in my CAN parser project. I am working on Eclipse and using Gradle to build. I added the correct dependency to the build.gradle file, but can not download the 3.x versions for some reason. There is not any problem during building, but after that the library does not appear in the "project and external dependencies" folder and I can not use it. Only 2.x working, so I use 2.3.0 now. Can you tell me what can cause this? Did you face it anytime in the past?
I would like to run my application on a Cohda MK5 device. Its architecture is armv7l, so the app try to load the armv7 shared object file, but JVM crashes with a fatal error similarly in the issue #24 . I have attached the log file and add some more details about my system:
root@MK5:~# cat /proc/cpuinfo
processor : 0
model name : ARMv7 Processor rev 10 (v7l)
BogoMIPS : 3.00
Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpd32
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x2
CPU part : 0xc09
CPU revision : 10
processor : 1
model name : ARMv7 Processor rev 10 (v7l)
BogoMIPS : 3.00
Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpd32
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x2
CPU part : 0xc09
CPU revision : 10
Hardware : Freescale i.MX6 Quad/DualLite (Device Tree)
Revision : 0000
Serial : 0000000000000000
root@MK5:~# uname -p
armv7l
root@MK5:~# lscpu
Architecture: armv7l
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Thread(s) per core: 1
Core(s) per socket: 2
Socket(s): 1
Model name: ARMv7 Processor rev 10 (v7l)
CPU max MHz: 792.0000
CPU min MHz: 396.0000
Hypervisor vendor: (null)
Virtualization type: full
Java method System.getProperty("os.arch") returns arm only. Can you add compatibility for armv7l or I should try to build the shared object file?
Regards,
Adam
@Boronyak sorry for the late response, github notifications and I are not friends. SIGILL definitely indicates an incompatible architecture.
I'd prefer if we can get version 3 going for you. Can you elaborate on that issue?
these are the artifacts that should work:
- the java part: https://repo1.maven.org/maven2/tel/schich/javacan-core/3.1.0/javacan-core-3.1.0.jar
- the native part: https://repo1.maven.org/maven2/tel/schich/javacan-core/3.1.0/javacan-core-3.1.0-armv7.jar
Can you confirm that these are the ones you used?
I'm not currently building armv7l, but as far as I understand the armv7 binary should work too. I could add explicit armv7l support later today.
@pschichtel I have successfully added these jar files to my project, but I had to add also slf4j and duplicate strategy property to built the jar file. I try to run it on Cohda but now I get the following error:
java.lang.UnsatisfiedLinkError: /tmp/javacan-core-11461710119285914790/libjavacan-core.so: /lib/arm-linux-gnueabihf/libc.so.6: version 'GLIBC_2.28' not found (required by /tmp/javacan-core-11461710119285914790/libjavacan-core.so) at java.base/jdk.internal.loader.NativeLibraries.load(Native Method) at java.base/jdk.internal.loader.NativeLibraries$NativeLibraryImpl.open(Unknown Source) at java.base/jdk.internal.loader.NativeLibraries.loadLibrary(Unknown Source) at java.base/jdk.internal.loader.NativeLibraries.loadLibrary(Unknown Source) at java.base/java.lang.ClassLoader.loadLibrary(Unknown Source) at java.base/java.lang.Runtime.load0(Unknown Source) at java.base/java.lang.System.load(Unknown Source) at tel.schich.javacan.platform.Platform.loadFromClassPath(Platform.java:113) at tel.schich.javacan.platform.Platform.loadExplicitLibrary(Platform.java:99) at tel.schich.javacan.platform.Platform.loadNativeLibrary(Platform.java:68) at tel.schich.javacan.JavaCAN.initialize(JavaCAN.java:44) at tel.schich.javacan.SocketCAN.<clinit>(SocketCAN.java:32) at tel.schich.javacan.CanChannels.newRawChannel(CanChannels.java:45) at can.CanInterface.<init>(CanInterface.java:21) at api.Main.main(Main.java:57)
On Cohda, Ubuntu 16.04 is running and only glibc 2.23 is available. It is not possible to upgrade to 18.04 and as I have read, install glibc 2.28 manually is risky. Do you have a version which uses 2.23 or older?
hmm I'm building using dockcross, not sure how much I can do about the glibc version except maybe using older images. I've seen the dockcross' armv7l image uses musl libc, would that be an option?
Yes, but only 1.1.9 is available. I do not know what is the required version.
I've build an armv7l version with musl libc:
you can also now override the docker image being used to cross-compile, but the interface must be compatible with dockcross.
I have added the armv7l jar file and installed musl, but now the following error is coming:
java.lang.UnsatisfiedLinkError: /tmp/javacan-core-5290316483724111401/libjavacan-core.so: /usr/lib/arm-linux-gnueabihf/libc.so: invalid ELF header at java.base/jdk.internal.loader.NativeLibraries.load(Native Method) at java.base/jdk.internal.loader.NativeLibraries$NativeLibraryImpl.open(Unknown Source) at java.base/jdk.internal.loader.NativeLibraries.loadLibrary(Unknown Source) at java.base/jdk.internal.loader.NativeLibraries.loadLibrary(Unknown Source) at java.base/java.lang.ClassLoader.loadLibrary(Unknown Source) at java.base/java.lang.Runtime.load0(Unknown Source) at java.base/java.lang.System.load(Unknown Source) at tel.schich.javacan.platform.Platform.loadFromClassPath(Platform.java:113) at tel.schich.javacan.platform.Platform.loadExplicitLibrary(Platform.java:99) at tel.schich.javacan.platform.Platform.loadNativeLibrary(Platform.java:68) at tel.schich.javacan.JavaCAN.initialize(JavaCAN.java:44) at tel.schich.javacan.SocketCAN.<clinit>(SocketCAN.java:32) at tel.schich.javacan.CanChannels.newRawChannel(CanChannels.java:45) at can.CanInterface.<init>(CanInterface.java:21) at api.Main.main(Main.java:57)
I did not find any useful information on the internet to solve this problem. Am I missing some package or configuration?
apparently your libc.so is not an actual library. not sure how that happens and how to solve it.
I could try statically linking musl
@Boronyak Can you give this one a try: https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220306.150726-3-armv7l.jar
I should be linked statically with musl libc (so you don't even need it installed).
Unfortunately I am getting the same error.
@Boronyak Can you give this one a try: https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220306.150726-3-armv7l.jar
I should be linked statically with musl libc (so you don't even need it installed).
@pschichtel I aggree that this static linking would be an option too.
I have found this article on github. The problem is similar as mine and they suggest to build on a machine which has lower glibc version. Is is possible to do that or it only depends on which docker image you use?
You can override the build container on lastest master (it's documented in the readme in the building section). I haven't immediately found an appropriate version of dockcross that has glibc 2.23, but if you find one you can just use that version of the container.
I think there is also some documentation on dockcross' side on how to build custom dockcross containers.
@Boronyak Can you give this one a try: https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220306.150726-3-armv7l.jar
I should be linked statically with musl libc (so you don't even need it installed).
@pschichtel It is possible that I misunderstood something. This jar contains the native component with statically linked musl libc? If yes, then why is it try to use glibc?
file also identifies it as dynamically linked... I'll have a look...
Just checked the binaries and it doesn't look like it depends on any libc:
$ readelf -d armv7l/libjavacan-core.so
Dynamic section at offset 0x8f38 contains 21 entries:
Tag Type Name/Value
0x0000000c (INIT) 0x1f14
0x0000000d (FINI) 0x72c4
0x00000019 (INIT_ARRAY) 0x18f2c
0x0000001b (INIT_ARRAYSZ) 4 (bytes)
0x0000001a (FINI_ARRAY) 0x18f30
0x0000001c (FINI_ARRAYSZ) 4 (bytes)
0x00000004 (HASH) 0xf4
0x6ffffef5 (GNU_HASH) 0x458
0x00000005 (STRTAB) 0xf84
0x00000006 (SYMTAB) 0x824
0x0000000a (STRSZ) 3501 (bytes)
0x0000000b (SYMENT) 16 (bytes)
0x00000003 (PLTGOT) 0x19000
0x00000002 (PLTRELSZ) 384 (bytes)
0x00000014 (PLTREL) REL
0x00000017 (JMPREL) 0x1d94
0x00000011 (REL) 0x1d34
0x00000012 (RELSZ) 96 (bytes)
0x00000013 (RELENT) 8 (bytes)
0x6ffffffa (RELCOUNT) 7
0x00000000 (NULL) 0x0
For reference here is the output for the x86_64 binary, notice the first entry:
$ readelf -d x86_64/libjavacan-core.so
Dynamic section at offset 0x5e20 contains 24 entries:
Tag Type Name/Value
0x0000000000000001 (NEEDED) Shared library: [libc.so.6]
0x000000000000000c (INIT) 0x2000
0x000000000000000d (FINI) 0x34ac
0x0000000000000019 (INIT_ARRAY) 0x6e10
0x000000000000001b (INIT_ARRAYSZ) 8 (bytes)
0x000000000000001a (FINI_ARRAY) 0x6e18
0x000000000000001c (FINI_ARRAYSZ) 8 (bytes)
0x000000006ffffef5 (GNU_HASH) 0x260
0x0000000000000005 (STRTAB) 0xd70
0x0000000000000006 (SYMTAB) 0x4d0
0x000000000000000a (STRSZ) 3271 (bytes)
0x000000000000000b (SYMENT) 24 (bytes)
0x0000000000000003 (PLTGOT) 0x7000
0x0000000000000002 (PLTRELSZ) 864 (bytes)
0x0000000000000014 (PLTREL) RELA
0x0000000000000017 (JMPREL) 0x1bb8
0x0000000000000007 (RELA) 0x1b10
0x0000000000000008 (RELASZ) 168 (bytes)
0x0000000000000009 (RELAENT) 24 (bytes)
0x000000006ffffffe (VERNEED) 0x1af0
0x000000006fffffff (VERNEEDNUM) 1
0x000000006ffffff0 (VERSYM) 0x1a38
0x000000006ffffff9 (RELACOUNT) 3
0x0000000000000000 (NULL) 0x0
Can you make sure that you are really using the right library?
@Boronyak Can you give this one a try: https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220306.150726-3-armv7l.jar
I should be linked statically with musl libc (so you don't even need it installed).
I have downloaded this jar file and replaced the old one in my project and built again the executable jar. I got the same elf header error. I have just checked the native library with the same command as you and I see libc.so as a needed library. Maybe did you upload a wrong jar file?
I just downloaded this:
https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220310.224643-5-armv7l.jar
That has been build via GitHub Action:
https://github.com/pschichtel/JavaCAN/runs/5503667342
The SHA256 of the javacan-core-3.1.1-20220310.224643-5-armv7l.jar file:
6715eb028b916a9b5644971b6cc3cd9e01a43b73d26a408fbaab99ad3b6b0a00
The SHA256 of the libjavacan-core.so file:
21ffc52a6b7767826d8ca45c33da772f47f6697bb3b2173676f50d39e1516d91
$ readelf -d libjavacan-core.so
Dynamic section at offset 0x8f38 contains 21 entries:
Tag Type Name/Value
0x0000000c (INIT) 0x1f14
0x0000000d (FINI) 0x72c4
0x00000019 (INIT_ARRAY) 0x18f2c
0x0000001b (INIT_ARRAYSZ) 4 (bytes)
0x0000001a (FINI_ARRAY) 0x18f30
0x0000001c (FINI_ARRAYSZ) 4 (bytes)
0x00000004 (HASH) 0xf4
0x6ffffef5 (GNU_HASH) 0x458
0x00000005 (STRTAB) 0xf84
0x00000006 (SYMTAB) 0x824
0x0000000a (STRSZ) 3501 (bytes)
0x0000000b (SYMENT) 16 (bytes)
0x00000003 (PLTGOT) 0x19000
0x00000002 (PLTRELSZ) 384 (bytes)
0x00000014 (PLTREL) REL
0x00000017 (JMPREL) 0x1d94
0x00000011 (REL) 0x1d34
0x00000012 (RELSZ) 96 (bytes)
0x00000013 (RELENT) 8 (bytes)
0x6ffffffa (RELCOUNT) 7
0x00000000 (NULL) 0x0
In recent commits I've made the maven build reproducible, so you should be able to produce the exact same hashes by building locally.
I just downloaded this:
https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220310.224643-5-armv7l.jar
You could manually download this jar, extract the libjavacan-core.so and put into your LD_LIBRARY_PATH. Alternatively you can set javacan.native.javacan-core.path to the absolute filesystem path to the libjavacan-core.so. The loader should prioritize this. If you enable trace logging for the tel.schich.javacan.platform.Platform logger it will tell you where it loaded the library from (I even improved the logging a bit on master just now).
I just downloaded this: https://oss.sonatype.org/content/repositories/snapshots/tel/schich/javacan-core/3.1.1-SNAPSHOT/javacan-core-3.1.1-20220310.224643-5-armv7l.jar
Now that works! :)
Thank you very much for your help!
Cool, so I'll release what I have on master in the next few days as 3.2