On 7/16/19 8:42 PM, Laszlo Ersek wrote: > On 07/16/19 18:59, Peter Maydell wrote: >> On Tue, 16 Jul 2019 at 17:51, Laszlo Ersek <ler...@redhat.com> wrote: >>> The issue still reproduces, so it makes sense for me to look at the host >>> kernel version... Well, I'm afraid it won't help much, for an upstream >>> investigation: >>> >>> 4.14.0-115.8.2.el7a.aarch64 >>> >>> This is the latest released kernel from "Red Hat Enterprise Linux for >>> ARM 64 7". >> >> OK. (I'm using 4.15.0-51-generic from ubuntu). >> >> Could you run with QEMU under gdb, and when it hits the >> assertion go back up a stack frame to the arm_cpu_realizefn() >> frame, and then "print /x cpu->isar" ? That should show us >> what we think we've got as ID registers from the kernel. >> (You might need to build QEMU with --enable-debug to get >> useful enough debug info to do that, not sure.) > > (My qemu build script always builds QEMU in two configs, the difference > being --prefix and --enable-debug.) > > This is what I got: > > (gdb) frame 4 > #4 0x00000000006a063c in arm_cpu_realizefn (dev=0x1761140, > errp=0xffffffffe540) > at .../qemu/target/arm/cpu.c:1159 > 1159 assert(no_aa32 || cpu_isar_feature(arm_div, cpu)); > (gdb) print /x cpu->isar > $1 = {id_isar0 = 0x0, id_isar1 = 0x0, id_isar2 = 0x0, id_isar3 = 0x0, > id_isar4 = 0x0, id_isar5 = 0x0, id_isar6 = 0x0, mvfr0 = 0x0, > mvfr1 = 0x0, mvfr2 = 0x0, id_aa64isar0 = 0x0, id_aa64isar1 = 0x0, > id_aa64pfr0 = 0x11, id_aa64pfr1 = 0x0, id_aa64mmfr0 = 0x0, > id_aa64mmfr1 = 0x0}
For ISAR0, DIVIDE=0 so cpu_isar_feature(arm_div, cpu)=false For AA64PFR0, EL0=1, EL1=1. EL0 = 1: EL0 can be executed in AArch64 state only. EL1 = 1: EL1 can be executed in AArch64 state only. so cpu_isar_feature(aa64_aa32, cpu)=false then no_aa32=true The commit description is "on a host that doesn't support aarch32 mode at all, neither arm_div nor jazelle will be supported either." Shouldn't we use a slighly different logic? Such: - assert(no_aa32 || cpu_isar_feature(arm_div, cpu)); + assert(no_aa32 && !cpu_isar_feature(arm_div, cpu));