received SIGILL, Illegal instruction from raspberry pi

[xhiksi]

Hello,

I am having troubles using my builded amule(not building, using), where cryptopp is one of needed libraries. I removed it the repository version and make it from github master.

Now, I have the line which is failing:

Program received signal SIGILL, Illegal instruction. 0x00000055558510e8 in PMULL_00 (b=..., a=...) at /home/imesemj/c++/cryptopp/arm_simd.h:160

where there is this line:
160 __asm__ ("pmull %0.1q, %1.1d, %2.1d \n\t"

it is an assembler within c/c++

Amule stucks randomly and may be this the problem ?

regards

[xhiksi]

I think this behavior, because this cpu of rpi3 model b have not aes and pmull instruction:

`Architecture: aarch64

CPU op-mode(s): 32-bit, 64-bit

Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Vendor ID: ARM
Model name: Cortex-A53
Model: 4
Thread(s) per core: 1
Core(s) per cluster: 4
Socket(s): -
Cluster(s): 1
Stepping: r0p4
CPU(s) scaling MHz: 50%
CPU max MHz: 1200.0000
CPU min MHz: 600.0000
BogoMIPS: 38.40
Flags: fp asimd evtstrm crc32 cpuid
Caches (sum of all):
L1d: 128 KiB (4 instances)
L1i: 128 KiB (4 instances)
L2: 512 KiB (1 instance)
Vulnerabilities:
Gather data sampling: Not affected
Itlb multihit: Not affected
L1tf: Not affected
Mds: Not affected
Meltdown: Not affected
Mmio stale data: Not affected
Reg file data sampling: Not affected
Retbleed: Not affected
Spec rstack overflow: Not affected
Spec store bypass: Not affected
Spectre v1: Mitigation; __user pointer sanitization
Spectre v2: Not affected
Srbds: Not affected
Tsx async abort: Not affected`

Question is: how can substitute hardware instruction with any software procedure ? support for old cpus

[xhiksi]

Hi
I replaced asm to arm_simd.h:160 with function of line 165:
return (uint64x2_t)(vmull_p64(vgetq_lane_u64(vreinterpretq_u64_u8(a),0),vgetq_lane_u64(vreinterpretq_u64_u8(b),0)));

and build library and amule from beginning. Now I have again SIGILL, illegal instruction:

`(gdb) run
Starting program: /usr/local/amule/bin/amuled -f
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/aarch64-linux-gnu/libthread_db.so.1".

Program received signal SIGILL, Illegal instruction.
0x00000055558431a4 in vaesdq_u8 (key=..., data=...) at /usr/lib/gcc/aarch64-linux-gnu/12/include/arm_neon.h:10260
10260 return __builtin_aarch64_crypto_aesdv16qi_uuu (data, key);
(gdb) backtrace
#0 0x00000055558431a4 in vaesdq_u8 (key=..., data=...) at /usr/lib/gcc/aarch64-linux-gnu/12/include/arm_neon.h:10260
#1 CryptoPP::CPU_ProbeAES () at rijndael_simd.cpp:130
#2 0x0000005555851780 in CryptoPP::DetectArmFeatures () at cpu.cpp:1148
#3 0x0000007ff7837898 in call_init (env=, argv=0x7ffffff3d8, argc=2) at ../csu/libc-start.c:145
#4 __libc_start_main_impl (main=0x5555610130 <main(int, char**)>, argc=2, argv=0x7ffffff3d8, init=, fini=, rtld_fini=,
stack_end=) at ../csu/libc-start.c:347
#5 0x00000055556181b0 in _start ()
(gdb)
#0 0x00000055558431a4 in vaesdq_u8 (key=..., data=...) at /usr/lib/gcc/aarch64-linux-gnu/12/include/arm_neon.h:10260
#1 CryptoPP::CPU_ProbeAES () at rijndael_simd.cpp:130
#2 0x0000005555851780 in CryptoPP::DetectArmFeatures () at cpu.cpp:1148
#3 0x0000007ff7837898 in call_init (env=, argv=0x7ffffff3d8, argc=2) at ../csu/libc-start.c:145
#4 __libc_start_main_impl (main=0x5555610130 <main(int, char**)>, argc=2, argv=0x7ffffff3d8, init=, fini=, rtld_fini=,
stack_end=) at ../csu/libc-start.c:347
#5 0x00000055556181b0 in _start ()`

All crypto file are compiling in this way:

g++ -DCRYPTOPP_DISABLE_ARM_CRC32 -DCRYPTOPP_DISABLE_ARM_PMULL -fPIC -fno-devirtualize -pthread -pipe -DNDEBUG -g2 -O3 -std=gnu++98 -c all_crypto_files.cpp

As can see here make script, identifies correctly that cpu has not this features and defines the macro CRYPTOPP_DISABLE_ARM_PMULL, which is not working. There is defined CRYPTOPP_DISABLE_ARM_CRC32, too.
Is this correct ? in cpu info above, I can see crc32 flag, it is a important improvemet if it is.

please help