Commit b320c03d authored by Yosry Ahmed's avatar Yosry Ahmed Committed by Sean Christopherson
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KVM: selftests: Kill eptPageTablePointer 



Replace the struct overlay with explicit bitmasks, which is clearer and
less error-prone. See commit f18b4aeb ("kvm: selftests: do not use
bitfields larger than 32-bits for PTEs") for an example of why bitfields
are not preferable.

Remove the unused PAGE_SHIFT_4K definition while at it.

No functional change intended.

Signed-off-by: default avatarYosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251230230150.4150236-5-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 60de4237

tools/testing/selftests/kvm/lib/x86/vmx.c

+17 −20
Original line number Diff line number Diff line
@@ -10,10 +10,16 @@ 
#include "processor.h"

#include "vmx.h"



#define PAGE_SHIFT_4K  12



#define KVM_EPT_PAGE_TABLE_MIN_PADDR 0x1c0000



#define EPTP_MT_SHIFT		0 /* EPTP memtype bits 2:0 */

#define EPTP_PWL_SHIFT		3 /* EPTP page walk length bits 5:3 */

#define EPTP_AD_ENABLED_SHIFT	6 /* EPTP AD enabled bit 6 */



#define EPTP_WB			(X86_MEMTYPE_WB << EPTP_MT_SHIFT)

#define EPTP_PWL_4		(3ULL << EPTP_PWL_SHIFT) /* PWL is (levels - 1) */

#define EPTP_AD_ENABLED		(1ULL << EPTP_AD_ENABLED_SHIFT)



bool enable_evmcs;



struct hv_enlightened_vmcs *current_evmcs;
@@ -34,14 +40,6 @@ struct eptPageTableEntry { 
	uint64_t suppress_ve:1;

};



struct eptPageTablePointer {

	uint64_t memory_type:3;

	uint64_t page_walk_length:3;

	uint64_t ad_enabled:1;

	uint64_t reserved_11_07:5;

	uint64_t address:40;

	uint64_t reserved_63_52:12;

};

int vcpu_enable_evmcs(struct kvm_vcpu *vcpu)

{

	uint16_t evmcs_ver;
@@ -196,16 +194,15 @@ static inline void init_vmcs_control_fields(struct vmx_pages *vmx) 
	vmwrite(PIN_BASED_VM_EXEC_CONTROL, rdmsr(MSR_IA32_VMX_TRUE_PINBASED_CTLS));



	if (vmx->eptp_gpa) {

		uint64_t ept_paddr;

		struct eptPageTablePointer eptp = {

			.memory_type = X86_MEMTYPE_WB,

			.page_walk_length = 3, /* + 1 */

			.ad_enabled = ept_vpid_cap_supported(VMX_EPT_VPID_CAP_AD_BITS),

			.address = vmx->eptp_gpa >> PAGE_SHIFT_4K,

		};

		uint64_t eptp = vmx->eptp_gpa | EPTP_WB | EPTP_PWL_4;



		TEST_ASSERT((vmx->eptp_gpa & ~PHYSICAL_PAGE_MASK) == 0,

			    "Illegal bits set in vmx->eptp_gpa");



		if (ept_vpid_cap_supported(VMX_EPT_VPID_CAP_AD_BITS))

			eptp |= EPTP_AD_ENABLED;



		memcpy(&ept_paddr, &eptp, sizeof(ept_paddr));

		vmwrite(EPT_POINTER, ept_paddr);

		vmwrite(EPT_POINTER, eptp);

		sec_exec_ctl |= SECONDARY_EXEC_ENABLE_EPT;

	}