> -----Original Message----- > From: Richard Henderson [mailto:richard.henderson@xxxxxxxxxx] > Sent: Monday, December 13, 2021 11:20 PM > To: Anup Patel <anup@xxxxxxxxxxxxxx>; Jiangyifei <jiangyifei@xxxxxxxxxx> > Cc: Bin Meng <bin.meng@xxxxxxxxxxxxx>; open list:RISC-V > <qemu-riscv@xxxxxxxxxx>; limingwang (A) <limingwang@xxxxxxxxxx>; KVM > General <kvm@xxxxxxxxxxxxxxx>; libvir-list@xxxxxxxxxx; Anup Patel > <anup.patel@xxxxxxx>; QEMU Developers <qemu-devel@xxxxxxxxxx>; > wanbo (G) <wanbo13@xxxxxxxxxx>; Palmer Dabbelt <palmer@xxxxxxxxxxx>; > kvm-riscv@xxxxxxxxxxxxxxxxxxx; Wanghaibin (D) > <wanghaibin.wang@xxxxxxxxxx>; Alistair Francis > <Alistair.Francis@xxxxxxx>; Fanliang (EulerOS) <fanliang@xxxxxxxxxx>; > Wubin (H) <wu.wubin@xxxxxxxxxx> > Subject: Re: [PATCH v2 10/12] target/riscv: Add kvm_riscv_get/put_regs_timer > > On 12/12/21 9:05 PM, Anup Patel wrote: > >> + ret = kvm_get_one_reg(cs, RISCV_TIMER_REG(env, state), ®); > >> + if (ret) { > >> + abort(); > >> + } > >> + env->kvm_timer_state = reg; > > > > Please read the timer frequency here. > > Yep. > > >> + > >> + env->kvm_timer_dirty = true; > >> +} > >> + > >> +static void kvm_riscv_put_regs_timer(CPUState *cs) { > >> + int ret; > >> + uint64_t reg; > >> + CPURISCVState *env = &RISCV_CPU(cs)->env; > >> + > >> + if (!env->kvm_timer_dirty) { > >> + return; > >> + } > > > > Over here, we should get the timer frequency and abort() with an error > > message if it does not match env->kvm_timer_frequency > > > > For now, migration will not work between Hosts with different timer > > frequency. > > You shouldn't have to do this every "put", only on migration, at which point you > can actually signal a migration error rather than aborting directly. > > > r~ Yes, it will be modified in the next series. Yifei
