Created attachment 187523 [details] Naïve fix. SUMMARY The STNP instruction, encountered in the Mali driver, is not handled. For reference: https://developer.arm.com/documentation/ddi0602/2023-06/Base-Instructions/STNP--Store-Pair-of-Registers--with-non-temporal-hint-?lang=en OBSERVED RESULT (Truncated output) ``` ARM64 front end: load_store disInstr(arm64): unhandled instruction 0xA8000C02 disInstr(arm64): 1010'1000 0000'0000 0000'1100 0000'0010 ==7901== valgrind: Unrecognised instruction at address 0x73cc4c0. ==7901== at 0x73CC4C0: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x73D48E7: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x73C5C33: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x737AC2F: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x63C2477: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x63822C7: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x638170B: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x639C18B: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x639CBA3: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x638E477: ??? (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x6341597: glTexSubImage2D (in /usr/lib/libmali.so.0.47.0) ==7901== by 0x5092A3B: ??? (in /usr/lib/libskia.so) ==7901== Your program just tried to execute an instruction that Valgrind ==7901== did not recognise. There are two possible reasons for this. ==7901== 1. Your program has a bug and erroneously jumped to a non-code ==7901== location. If you are running Memcheck and you just saw a ==7901== warning about a bad jump, it's probably your program's fault. ==7901== 2. The instruction is legitimate but Valgrind doesn't handle it, ==7901== i.e. it's Valgrind's fault. If you think this is the case or ==7901== you are not sure, please let us know and we'll try to fix it. ==7901== Either way, Valgrind will now raise a SIGILL signal which will ==7901== probably kill your program. ``` EXPECTED RESULT The instruction is handled. SOFTWARE/OS VERSIONS Windows: macOS: (available in the Info Center app, or by running `kinfo` in a terminal window) Linux/KDE Plasma: KDE Plasma Version: KDE Frameworks Version: Qt Version: ADDITIONAL INFORMATION I have attached a patch that at least superficially fixes the issue but I cannot myself confirm that it actually does the right thing. It relies on the assumption that L/STP is similar enough that they can be treated as the same. Hopefully it will help provide context.