It does still crash on current QEMU. The proximate cause of the crash is that you are trying to read from an address which is way outside RAM:
Trace 0: 0x7f8d50054340 [0000000000000000/00000000400195d8/0x82104000] strcmp PC=00000000400195d8 X00=000000104010ca28 X01=000000004001ec28 X02=0000000000000fe8 X03=00000000401098c8 X04=000000004010ba40 X05=5641526f44654b00 X06=1f276f6c62717372 X07=0000000000000000 X08=00000000ffffffda X09=00000000401097d0 X10=0101010101010101 X11=0000000000000000 X12=0000000000000000 X13=0000000000000000 X14=0000000000000000 X15=0000000000000000 X16=0000000040014610 X17=0000000000000008 X18=0000000000000000 X19=000000004010b9f0 X20=000000004001ec28 X21=000000084001ec20 X22=000000004001ec60 X23=000000004001ec40 X24=000000004001f548 X25=000000104001ec28 X26=000000104001ec40 X27=000000034001ec38 X28=0000000000000000 X29=00000000401098d0 X30=0000000040008a38 SP=00000000401098d0 PSTATE=40000005 -Z-- EL1h Taking exception 4 [Data Abort] ...from EL1 to EL1 ...with ESR 0x25/0x96000010 ...with FAR 0x104010ca28 ...with ELR 0x400195d8 ...to EL1 PC 0x40018200 PSTATE 0x3c5 where the insn at 0x400195d8 is (inside strcmp) 0x400195d8: f8408402 ldr x2, [x0], #8 You can see that x0 is is 000000104010ca28, so QEMU is correct to give the data abort here. Further diagnosis would require working back through the log to find out where that address came from, which will be easier for you to do since you have the source. NB: I recommend these options for producing the logfile: /tmp/q.log -d in_asm,int,cpu_reset,exec,cpu,guest_errors,nochain -singlestep Execution will be slower, but the crash here is pretty quick so that's not a problem, and these options mean that every insn executed will produce a "Trace" line and a CPU register dump. That's easier to understand and read (especially reading backwards) than logs produced when QEMU is doing its normal optimisations of chaining TBs together and putting multiple guest insns in each TB. -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1887854 Title: Spurious Data Abort on qemu-system-aarch64 Status in QEMU: New Bug description: When running RTEMS test psxndbm01.exe built for AArch64-ilp32 (this code is not yet publically available), the test generates a spurious data abort (the MMU and alignment checks should be disabled according to bits 1, 0 of SCTLR_EL1). The abort information is as follows: Taking exception 4 [Data Abort] ...from EL1 to EL1 ...with ESR 0x25/0x96000010 ...with FAR 0x104010ca28 ...with ELR 0x400195d8 ...to EL1 PC 0x40018200 PSTATE 0x3c5 The ESR indicates that a synchronous external abort has occurred. ESR EC field: 0b100101 From the ARMv8 technical manual: Data Abort taken without a change in Exception level. Used for MMU faults generated by data accesses, alignment faults other than those caused by Stack Pointer misalignment, and synchronous External aborts, including synchronous parity or ECC errors. Not used for debug related exceptions. ESR ISS field: 0b10000 From the ARMv8 technical manual: Synchronous External abort, not on translation table walk or hardware update of translation table. The following command line is used to invoke qemu: qemu-system-aarch64 -machine virt -cpu cortex-a53 -m 256M -no-reboot -nographic -serial mon:stdio -kernel build/aarch64/a53_ilp32_qemu/testsuites/psxtests/psxndbm01.exe -D qemu.log -d in_asm,int,cpu_reset,unimp,guest_errors This occurs on Qemu 3.1.0 as distributed via Debian and on Qemu 4.1 as built by the RTEMS source builder (4.1+minor patches). Edit: This bug can be worked around by getting and setting SCTLR without changing its value before each data abort would occur. This test needs 6 of these workarounds to operate successfully. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1887854/+subscriptions
