Valgrind version 3.26 is not compatible with latest ARMv8 (Valgrind has support till only ARMv8.2‑A, But all batch#2 targets like Pakala, Kaanapali, Glymur, Mahua etc will be using armv8-6a or above)​

[aravindpadala180461]

while testing memcheck catches mismatched mmap free" test failure as "no leaks were detected

Steps to reproduce:

1. Cross compilation the c program as below :

aarch64-linux-gnu-gcc -g memory_leak_demo.c -o memory_leak_demo
OR
aarch64-linux-gnu-gcc -g memory_leak_demo.c -o memory_leak_demo.o

2. Root the device "adb root"
3. Run following commands
   "setenforce 0"
   "mount -o rw,remount /"
4. Push the above binary onto device using "adb push memory_leak_demo /var/lib"
5. Move to shell using "adb shell"
6. Move to directory "/usr/bin"
7. Give valgrind command :
   "valgrind --tool=memcheck --leak-check=yes --show-reachable=yes --num-callers=20 --track-fds=yes /var/lib/memory_leak_demo"

Observed Results:
==2141== Process terminating with default action of signal 4 (SIGILL): dumping core

==2141== Illegal opcode at address 0x4028268

==2141== at 0x4028268: _dl_sysdep_parse_arguments (dl-sysdep.c:96)

==2141== by 0x40285DF: _dl_sysdep_start (dl-sysdep.c:106)

==2141== by 0x402994B: _dl_start_final (rtld.c:496)

==2141== by 0x402994B: _dl_start (rtld.c:581)

==2141== by 0x402D853: (below main) (dl-start.S:31)

==2141==

==2141== FILE DESCRIPTORS: 3 open (3 inherited) at exit.

==2141==

==2141== HEAP SUMMARY:

==2141== in use at exit: 0 bytes in 0 blocks

==2141== total heap usage: 0 allocs, 0 frees, 0 bytes allocated

==2141==

==2141== All heap blocks were freed -- no leaks are possible

==2141==

==2141== For lists of detected and suppressed errors, rerun with: -s

==2141== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

Expected Results: [As in Lemans]
==2093== LEAK SUMMARY:

==2093== definitely lost: 108 bytes in 2 blocks

==2093== indirectly lost: 50 bytes in 1 blocks

==2093== possibly lost: 0 bytes in 0 blocks

==2093== still reachable: 0 bytes in 0 blocks

==2093== suppressed: 0 bytes in 0 blocks

==2093==

==2093== For lists of detected and suppressed errors, rerun with: -s

==2093== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 0 from 0)

[aravindpadala180461]

We are using Vaigrind version 3.26 which is latest and if we see in the release notes at link we will find that Valgrind has support till only ARMv8.2‑A.

Now the batch#2 targets like Pakala, Kaanapali, Glymur, Mahua etc will be using armv8-6a or above.

So what happens is, all the system libraries will be compiled with armv8.6-a or armv8.7-a and GCC emits Pointer Authentication Code (PAC) instructions in ld.so, libc.so etc.

Now when Valgrind tries to run the program it loads ld.so first even before calling main() function and it hits retaa error ( 0xD65F0BFF decodes to RETAA (Return, authenticate using A-key) on arm64 systems that have PAC enabled.)

And so as Valgrind does not support it, it leads to crash even before the program starts execution.

[ricardosalveti]

Can you reproduce this issue with current valgrind master and report the bug upstream?