On 31 January 2018 at 18:51, Alistair Francis <alistai...@gmail.com> wrote: > On Wed, Jan 31, 2018 at 10:48 AM, Peter Maydell > <peter.mayd...@linaro.org> wrote: >> On 31 January 2018 at 18:17, Alistair Francis <alistai...@gmail.com> wrote: >>> On Wed, Jan 31, 2018 at 9:13 AM, Paolo Bonzini <pbonz...@redhat.com> wrote: >>>> cpu->halted = false likewise should not be needed here, but you cannot >>>> just clear CPU_INTERRUPT_HALT either. You need to set a *different* >>>> interrupt request bit (the dummy CPU_INTERRUPT_EXITTB will do) and >>>> cpu_handle_halt will clear cpu->halted. >>> >>> The problem with that is that I hit this assert for ARM CPUs: >>> >>> qemu-system-aarch64: ./target/arm/cpu.h:1446: arm_el_is_aa64: >>> Assertion `el >= 1 && el <= 3' failed. >> >> Backtrace from when you hit that might be useful... > > Here it is: > > (gdb) bt > #0 0x00007ffff1a030bb in __GI_raise (sig=sig@entry=6) at > ../sysdeps/unix/sysv/linux/raise.c:51 > #1 0x00007ffff1a04f5d in __GI_abort () at abort.c:90 > #2 0x00007ffff19faf17 in __assert_fail_base (fmt=<optimized out>, > assertion=assertion@entry=0x555555cf86c4 "el >= 1 && el <= 3", > file=file@entry=0x555555cf8660 > "/scratch/alistai/master-qemu/target/arm/cpu.h", line=line@entry=1446, > function=function@entry=0x555555d314e8 <__PRETTY_FUNCTION__.24916> > "arm_el_is_aa64") at assert.c:92 > #3 0x00007ffff19fafc2 in __GI___assert_fail > (assertion=assertion@entry=0x555555cf86c4 "el >= 1 && el <= 3", > file=file@entry=0x555555cf8660 > "/scratch/alistai/master-qemu/target/arm/cpu.h", line=line@entry=1446, > function=function@entry=0x555555d314e8 <__PRETTY_FUNCTION__.24916> > "arm_el_is_aa64") at assert.c:101 > #4 0x00005555557eb872 in arm_el_is_aa64 (el=0, env=0x55555723c7f8) at > /scratch/alistai/master-qemu/target/arm/cpu.h:1446 > #5 0x0000555555951233 in arm_el_is_aa64 (el=0, env=0x55555723c7f8) at > /scratch/alistai/master-qemu/target/arm/cpu.h:1838 > #6 0x0000555555951233 in arm_cpu_do_interrupt (cs=0x555557234550) at > /scratch/alistai/master-qemu/target/arm/helper.c:8020
The problem is here (or further down the callstack) -- you definitely don't want to be trying to take an interrupt from the guest's perspective, which is what arm_cpu_do_interrupt() is for... This is probably happening because cpu->exception_index isn't right at this point (though the arm code has a habit of leaving it set to whatever its value was last...) > #7 0x000055555585e75b in cpu_handle_exception (ret=<synthetic > pointer>, cpu=0x555556c64200) > at /scratch/alistai/master-qemu/accel/tcg/cpu-exec.c:532 > #8 0x000055555585e75b in cpu_exec (cpu=cpu@entry=0x555557234550) at > /scratch/alistai/master-qemu/accel/tcg/cpu-exec.c:748 > #9 0x000055555582d963 in tcg_cpu_exec (cpu=0x555557234550) at > /scratch/alistai/master-qemu/cpus.c:1297 > #10 0x000055555582d963 in qemu_tcg_cpu_thread_fn (arg=0x555557234550) > at /scratch/alistai/master-qemu/cpus.c:1502 > #11 0x00007ffff1db37fc in start_thread (arg=0x7ffef6b43700) at > pthread_create.c:465 > #12 0x00007ffff1ae0b5f in clone () at > ../sysdeps/unix/sysv/linux/x86_64/clone.S:95 thanks -- PMM
