Commit cb4f0843 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

Merge tag 'kvm-riscv-fixes-5.17-1' of https://github.com/kvm-riscv/linux into HEAD 

KVM/riscv fixes for 5.17, take #1

- Rework guest entry logic

- Make CY, TM, and IR counters accessible in VU mode

- Fix SBI implementation version
parents 8cfe148a 40327154

arch/riscv/kvm/vcpu.c

+31 −17
Original line number Diff line number Diff line
@@ -90,6 +90,7 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)

{

	struct kvm_cpu_context *cntx;

	struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;



	/* Mark this VCPU never ran */

	vcpu->arch.ran_atleast_once = false;
@@ -106,6 +107,9 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 
	cntx->hstatus |= HSTATUS_SPVP;

	cntx->hstatus |= HSTATUS_SPV;



	/* By default, make CY, TM, and IR counters accessible in VU mode */

	reset_csr->scounteren = 0x7;



	/* Setup VCPU timer */

	kvm_riscv_vcpu_timer_init(vcpu);
@@ -699,6 +703,20 @@ static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu) 
	csr_write(CSR_HVIP, csr->hvip);

}



/*

 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while

 * the vCPU is running.

 *

 * This must be noinstr as instrumentation may make use of RCU, and this is not

 * safe during the EQS.

 */

static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu)

{

	guest_state_enter_irqoff();

	__kvm_riscv_switch_to(&vcpu->arch);

	guest_state_exit_irqoff();

}



int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)

{

	int ret;
@@ -790,9 +808,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 
			continue;

		}



		guest_enter_irqoff();

		guest_timing_enter_irqoff();



		__kvm_riscv_switch_to(&vcpu->arch);

		kvm_riscv_vcpu_enter_exit(vcpu);



		vcpu->mode = OUTSIDE_GUEST_MODE;

		vcpu->stat.exits++;
@@ -812,25 +830,21 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 
		kvm_riscv_vcpu_sync_interrupts(vcpu);



		/*

		 * We may have taken a host interrupt in VS/VU-mode (i.e.

		 * while executing the guest). This interrupt is still

		 * pending, as we haven't serviced it yet!

		 * We must ensure that any pending interrupts are taken before

		 * we exit guest timing so that timer ticks are accounted as

		 * guest time. Transiently unmask interrupts so that any

		 * pending interrupts are taken.

		 *

		 * We're now back in HS-mode with interrupts disabled

		 * so enabling the interrupts now will have the effect

		 * of taking the interrupt again, in HS-mode this time.

		 * There's no barrier which ensures that pending interrupts are

		 * recognised, so we just hope that the CPU takes any pending

		 * interrupts between the enable and disable.

		 */

		local_irq_enable();

		local_irq_disable();



		/*

		 * We do local_irq_enable() before calling guest_exit() so

		 * that if a timer interrupt hits while running the guest

		 * we account that tick as being spent in the guest. We

		 * enable preemption after calling guest_exit() so that if

		 * we get preempted we make sure ticks after that is not

		 * counted as guest time.

		 */

		guest_exit();

		guest_timing_exit_irqoff();



		local_irq_enable();



		preempt_enable();

arch/riscv/kvm/vcpu_sbi_base.c

+2 −1
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
#include <linux/errno.h>

#include <linux/err.h>

#include <linux/kvm_host.h>

#include <linux/version.h>

#include <asm/csr.h>

#include <asm/sbi.h>

#include <asm/kvm_vcpu_timer.h>
@@ -32,7 +33,7 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, 
		*out_val = KVM_SBI_IMPID;

		break;

	case SBI_EXT_BASE_GET_IMP_VERSION:

		*out_val = 0;

		*out_val = LINUX_VERSION_CODE;

		break;

	case SBI_EXT_BASE_PROBE_EXT:

		if ((cp->a0 >= SBI_EXT_EXPERIMENTAL_START &&