Commit 94f5e8a4 authored by David Brazdil's avatar David Brazdil Committed by Marc Zyngier
Browse files

KVM: arm64: Create nVHE copy of cpu_logical_map 



When KVM starts validating host's PSCI requests, it will need to map
MPIDR back to the CPU ID. To this end, copy cpu_logical_map into nVHE
hyp memory when KVM is initialized.

Only copy the information for CPUs that are online at the point of KVM
initialization so that KVM rejects CPUs whose features were not checked
against the finalized capabilities.

Signed-off-by: default avatarDavid Brazdil <dbrazdil@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-15-dbrazdil@google.com
parent 687413d3

arch/arm64/kvm/arm.c

+19 −0
Original line number Diff line number Diff line
@@ -64,6 +64,8 @@ static bool vgic_present; 
static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);

DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);



extern u64 kvm_nvhe_sym(__cpu_logical_map)[NR_CPUS];



int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)

{

	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
@@ -1506,6 +1508,20 @@ static inline void hyp_cpu_pm_exit(void) 
}

#endif



static void init_cpu_logical_map(void)

{

	unsigned int cpu;



	/*

	 * Copy the MPIDR <-> logical CPU ID mapping to hyp.

	 * Only copy the set of online CPUs whose features have been chacked

	 * against the finalized system capabilities. The hypervisor will not

	 * allow any other CPUs from the `possible` set to boot.

	 */

	for_each_online_cpu(cpu)

		kvm_nvhe_sym(__cpu_logical_map)[cpu] = cpu_logical_map(cpu);

}



static int init_common_resources(void)

{

	return kvm_set_ipa_limit();
@@ -1684,6 +1700,9 @@ static int init_hyp_mode(void) 
		}

	}



	if (is_protected_kvm_enabled())

		init_cpu_logical_map();



	return 0;



out_err:

arch/arm64/kvm/hyp/nvhe/hyp-smp.c

+16 −0
Original line number Diff line number Diff line
@@ -8,6 +8,22 @@ 
#include <asm/kvm_hyp.h>

#include <asm/kvm_mmu.h>



/*

 * nVHE copy of data structures tracking available CPU cores.

 * Only entries for CPUs that were online at KVM init are populated.

 * Other CPUs should not be allowed to boot because their features were

 * not checked against the finalized system capabilities.

 */

u64 __ro_after_init __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };



u64 cpu_logical_map(unsigned int cpu)

{

	if (cpu >= ARRAY_SIZE(__cpu_logical_map))

		hyp_panic();



	return __cpu_logical_map[cpu];

}



unsigned long __hyp_per_cpu_offset(unsigned int cpu)

{

	unsigned long *cpu_base_array;

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