[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64
From: |
K |
Subject: |
[Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64 |
Date: |
Fri, 17 Jul 2020 11:50:58 -0000 |
I would have thought that TLB considerations would not apply when the
MMU is disabled (RTEMS runs in a completely flat memory space). I'll try
to reproduce on more modern QEMU today. Thanks for taking a look at
this.
--
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
- [Bug 1887854] [NEW] Spurious Data Abort on qemu-system-aarch64, K, 2020/07/16
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64, K, 2020/07/16
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64, Peter Maydell, 2020/07/16
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64,
K <=
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64, Peter Maydell, 2020/07/17
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64, K, 2020/07/17
- [Bug 1887854] Re: Spurious Data Abort on qemu-system-aarch64, K, 2020/07/20