Commit 6fc469d6 authored by Marc Zyngier's avatar Marc Zyngier Committed by Junhao He
Browse files

KVM: arm64: Exclude host_debug_data from vcpu_arch 

mainline inclusion
from mainline-v6.9-rc1
commit 6db55734ec4008da39e10d2fffa913fd9751ccaa
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8EC9K
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6db55734ec4008da39e10d2fffa913fd9751ccaa



--------------------------------

Keeping host_debug_state on a per-vcpu basis is completely
pointless. The lifetime of this data is only that of the inner
run-loop, which means it is never accessed outside of the core
EL2 code.

Move the structure into kvm_host_data, and save over 500 bytes
per vcpu.

Reviewed-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
parent 5c288417

arch/arm64/include/asm/kvm_host.h

+17 −14
Original line number Diff line number Diff line
@@ -463,6 +463,19 @@ struct kvm_cpu_context { 
 */

struct kvm_host_data {

	struct kvm_cpu_context host_ctxt;



	/*

	 * host_debug_state contains the host registers which are

	 * saved and restored during world switches.

	 */

	 struct {

		/* {Break,watch}point registers */

		struct kvm_guest_debug_arch regs;

		/* Statistical profiling extension */

		u64 pmscr_el1;

		/* Self-hosted trace */

		u64 trfcr_el1;

	} host_debug_state;

};



struct kvm_host_psci_config {
@@ -556,11 +569,10 @@ struct kvm_vcpu_arch { 
	 * We maintain more than a single set of debug registers to support

	 * debugging the guest from the host and to maintain separate host and

	 * guest state during world switches. vcpu_debug_state are the debug

	 * registers of the vcpu as the guest sees them.  host_debug_state are

	 * the host registers which are saved and restored during

	 * world switches. external_debug_state contains the debug

	 * values we want to debug the guest. This is set via the

	 * KVM_SET_GUEST_DEBUG ioctl.

	 * registers of the vcpu as the guest sees them.

	 *

	 * external_debug_state contains the debug values we want to debug the

	 * guest. This is set via the KVM_SET_GUEST_DEBUG ioctl.

	 *

	 * debug_ptr points to the set of debug registers that should be loaded

	 * onto the hardware when running the guest.
@@ -572,15 +584,6 @@ struct kvm_vcpu_arch { 
	struct user_fpsimd_state *host_fpsimd_state;	/* hyp VA */

	struct task_struct *parent_task;



	struct {

		/* {Break,watch}point registers */

		struct kvm_guest_debug_arch regs;

		/* Statistical profiling extension */

		u64 pmscr_el1;

		/* Self-hosted trace */

		u64 trfcr_el1;

	} host_debug_state;



	/* VGIC state */

	struct vgic_cpu vgic_cpu;

	struct arch_timer_cpu timer_cpu;

arch/arm64/kvm/hyp/include/hyp/debug-sr.h

+2 −2
Original line number Diff line number Diff line
@@ -137,7 +137,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu) 


	host_ctxt = host_data_ptr(host_ctxt);

	guest_ctxt = &vcpu->arch.ctxt;

	host_dbg = &vcpu->arch.host_debug_state.regs;

	host_dbg = host_data_ptr(host_debug_state.regs);

	guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);



	__debug_save_state(host_dbg, host_ctxt);
@@ -156,7 +156,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu) 


	host_ctxt = host_data_ptr(host_ctxt);

	guest_ctxt = &vcpu->arch.ctxt;

	host_dbg = &vcpu->arch.host_debug_state.regs;

	host_dbg = host_data_ptr(host_debug_state.regs);

	guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);



	__debug_save_state(guest_dbg, guest_ctxt);

arch/arm64/kvm/hyp/nvhe/debug-sr.c

+4 −4
Original line number Diff line number Diff line
@@ -83,10 +83,10 @@ void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) 
{

	/* Disable and flush SPE data generation */

	if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))

		__debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);

		__debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1));

	/* Disable and flush Self-Hosted Trace generation */

	if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))

		__debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);

		__debug_save_trace(host_data_ptr(host_debug_state.trfcr_el1));

}



void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
@@ -97,9 +97,9 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu) 
void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)

{

	if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))

		__debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);

		__debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1));

	if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE))

		__debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);

		__debug_restore_trace(*host_data_ptr(host_debug_state.trfcr_el1));

}



void __debug_switch_to_host(struct kvm_vcpu *vcpu)