Hi Alistair: Thanks for your reply. I'll modify the change follow your suggestion, and push the new change, pls help to review again.
---- Replied Message ---- From Alistair Francis<alistai...@gmail.com> <mailto:alistai...@gmail.com> Date 6/23/2023 10:15 To liguang.zhang<18622748...@163.com> <mailto:18622748...@163.com> Cc qemu-devel@nongnu.org<qemu-devel@nongnu.org> , <mailto:qemu-devel@nongnu.org>pbonz...@redhat.com<pbonz...@redhat.com> , <mailto:pbonz...@redhat.com>张立广<liguang.zh...@hexintek.com> <mailto:liguang.zh...@hexintek.com> Subject Re: [PATCH] target/riscv: fix the issue of guest reboot then no response or crash in kvm-mode On Mon, Jun 12, 2023 at 11:07 PM liguang.zhang <18622748...@163.com> wrote: From: "liguang.zhang" <liguang.zh...@hexintek.com> Hello, thanks for the patch There have a issue of guest reboot bug in kvm-mode: 1. in guest shell just run the reboot, guest can't reboot success, and host kvm stop the vcpu schedual. 2. for smp guest, ctrl+a+c switch to qemu command, use system_reset command to reset the guest, then vcpu crash There are two issues when rebooting a guest using KVM 1. When the guest initiates a reboot the host is unable to stop the vcpu 2. When running a SMP guest the qemu monitor system_reset causes a vcpu crash This can be fixed by clearing the CSR values at reset and syncing the MPSTATE with the host. kernel log ```shell $reboot The system is going down NOW! Sent SIGTERM to all processes logout Sent SIGKILL to all processes Requesting system reboot ``` then no response for qemu command: $system_reset: kernel log: ```shell [ 53.739556] kvm [150]: VCPU exit error -95 [ 53.739563] kvm [148]: VCPU exit error -95 [ 53.739557] kvm [149]: VCPU exit error -95 [ 53.740957] kvm [149]: SEPC=0x0 SSTATUS=0x200004120 HSTATUS=0x2002001c0 [ 53.740957] kvm [148]: SEPC=0x0 SSTATUS=0x200004120 HSTATUS=0x2002001c0 [ 53.741054] kvm [148]: SCAUSE=0x14 STVAL=0x0 HTVAL=0x0 HTINST=0x0 [ 53.741058] kvm [149]: SCAUSE=0x14 STVAL=0x0 HTVAL=0x0 HTINST=0x0 [ 53.756187] kvm [150]: SEPC=0x0 SSTATUS=0x200004120 HSTATUS=0x2002001c0 [ 53.757797] kvm [150]: SCAUSE=0x14 STVAL=0x0 HTVAL=0x0 HTINST=0x0 ``` solution: add reset csr and context for riscv vcpu qemu ioctl reset vcpu->arch.power_off state of kvm tests: qemu-system-riscv64 -M virt -bios none -kernel Image \ -smp 4 -enable-kvm \ -append "rootwait root=/dev/vda ro" \ -drive file=rootfs.ext2,format=raw,id=hd0 \ -device virtio-blk-device,drive=hd0 in guest shell: $reboot qemu command: $system_reset --- v2: - update submit description Signed-off-by: liguang.zhang <liguang.zh...@hexintek.com> --- target/riscv/kvm.c | 43 ++++++++++++++++++++++++++++++++++++++++ target/riscv/kvm_riscv.h | 1 + 2 files changed, 44 insertions(+) diff --git a/target/riscv/kvm.c b/target/riscv/kvm.c index 0f932a5b96..c6a7824c9e 100644 --- a/target/riscv/kvm.c +++ b/target/riscv/kvm.c @@ -42,6 +42,8 @@ #include "migration/migration.h" #include "sysemu/runstate.h" +static bool cap_has_mp_state; + static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type, uint64_t idx) { @@ -335,6 +337,25 @@ int kvm_arch_get_registers(CPUState *cs) return ret; } +int kvm_riscv_set_mpstate_to_kvm(RISCVCPU *cpu, int state) This should probably be called: kvm_riscv_sync_mpstate_to_kvm() instead +{ + if (cap_has_mp_state) { + No newline required Otherwise the patch looks good Alistair + struct kvm_mp_state mp_state = { + .mp_state = state + }; + + int ret = kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MP_STATE, &mp_state); + if (ret) { + fprintf(stderr, "%s: failed to set MP_STATE %d/%s\n", + __func__, ret, strerror(-ret)); + return -1; + } + } + + return 0; +} + int kvm_arch_put_registers(CPUState *cs, int level) { int ret = 0; @@ -354,6 +375,18 @@ int kvm_arch_put_registers(CPUState *cs, int level) return ret; } + if (KVM_PUT_RESET_STATE == level) { + RISCVCPU *cpu = RISCV_CPU(cs); + if (cs->cpu_index == 0) { + ret = kvm_riscv_set_mpstate_to_kvm(cpu, KVM_MP_STATE_RUNNABLE); + } else { + ret = kvm_riscv_set_mpstate_to_kvm(cpu, KVM_MP_STATE_STOPPED); + } + if (ret) { + return ret; + } + } + return ret; } @@ -428,6 +461,7 @@ int kvm_arch_add_msi_route_post(struct kvm_irq_routing_entry *route, int kvm_arch_init(MachineState *ms, KVMState *s) { + cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE); return 0; } @@ -506,10 +540,19 @@ void kvm_riscv_reset_vcpu(RISCVCPU *cpu) if (!kvm_enabled()) { return; } + for (int i=0; i<32; i++) + env->gpr[i] = 0; env->pc = cpu->env.kernel_addr; env->gpr[10] = kvm_arch_vcpu_id(CPU(cpu)); /* a0 */ env->gpr[11] = cpu->env.fdt_addr; /* a1 */ env->satp = 0; + env->mie = 0; + env->stvec = 0; + env->sscratch = 0; + env->sepc = 0; + env->scause = 0; + env->stval = 0; + env->mip = 0; } void kvm_riscv_set_irq(RISCVCPU *cpu, int irq, int level) diff --git a/target/riscv/kvm_riscv.h b/target/riscv/kvm_riscv.h index ed281bdce0..4a4c262820 100644 --- a/target/riscv/kvm_riscv.h +++ b/target/riscv/kvm_riscv.h @@ -21,5 +21,6 @@ void kvm_riscv_reset_vcpu(RISCVCPU *cpu); void kvm_riscv_set_irq(RISCVCPU *cpu, int irq, int level); +int kvm_riscv_set_mpstate_to_kvm(RISCVCPU *cpu, int state); #endif -- 2.17.1 This message contains confidential information and is intended only for the individual(s) addressed in the message. 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