Commit e8ef2790 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: Add sanitisation to SCTLR_EL2 



Sanitise SCTLR_EL2 the usual way. The most important aspect of
this is that we benefit from SCTLR_EL2.SPAN being RES1 when
HCR_EL2.E2H==0.

Reviewed-by: default avatarFuad Tabba <tabba@google.com>
Tested-by: default avatarFuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260202184329.2724080-20-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent fb40cb15

arch/arm64/include/asm/kvm_host.h

+1 −1
Original line number Diff line number Diff line
@@ -495,7 +495,6 @@ enum vcpu_sysreg { 
	DBGVCR32_EL2,	/* Debug Vector Catch Register */



	/* EL2 registers */

	SCTLR_EL2,	/* System Control Register (EL2) */

	ACTLR_EL2,	/* Auxiliary Control Register (EL2) */

	CPTR_EL2,	/* Architectural Feature Trap Register (EL2) */

	HACR_EL2,	/* Hypervisor Auxiliary Control Register */
@@ -526,6 +525,7 @@ enum vcpu_sysreg { 


	/* Anything from this can be RES0/RES1 sanitised */

	MARKER(__SANITISED_REG_START__),

	SCTLR_EL2,	/* System Control Register (EL2) */

	TCR2_EL2,	/* Extended Translation Control Register (EL2) */

	SCTLR2_EL2,	/* System Control Register 2 (EL2) */

	MDCR_EL2,	/* Monitor Debug Configuration Register (EL2) */

arch/arm64/kvm/config.c

+82 −0
Original line number Diff line number Diff line
@@ -1123,6 +1123,84 @@ static const struct reg_bits_to_feat_map sctlr_el1_feat_map[] = { 
static const DECLARE_FEAT_MAP(sctlr_el1_desc, SCTLR_EL1,

			      sctlr_el1_feat_map, FEAT_AA64EL1);



static const struct reg_bits_to_feat_map sctlr_el2_feat_map[] = {

	NEEDS_FEAT_FLAG(SCTLR_EL2_CP15BEN,

			RES1_WHEN_E2H0 | REQUIRES_E2H1,

			FEAT_AA32EL0),

	NEEDS_FEAT_FLAG(SCTLR_EL2_ITD	|

			SCTLR_EL2_SED,

			RES1_WHEN_E2H1 | REQUIRES_E2H1,

			FEAT_AA32EL0),

	NEEDS_FEAT_FLAG(SCTLR_EL2_BT0, REQUIRES_E2H1, FEAT_BTI),

	NEEDS_FEAT(SCTLR_EL2_BT, FEAT_BTI),

	NEEDS_FEAT_FLAG(SCTLR_EL2_CMOW, REQUIRES_E2H1, FEAT_CMOW),

	NEEDS_FEAT_FLAG(SCTLR_EL2_TSCXT,

			RES1_WHEN_E2H1 | REQUIRES_E2H1,

			feat_csv2_2_csv2_1p2),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EIS	|

			SCTLR_EL2_EOS,

			AS_RES1, FEAT_ExS),

	NEEDS_FEAT(SCTLR_EL2_EnFPM, FEAT_FPMR),

	NEEDS_FEAT(SCTLR_EL2_IESB, FEAT_IESB),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EnALS, REQUIRES_E2H1, FEAT_LS64),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EnAS0, REQUIRES_E2H1, FEAT_LS64_ACCDATA),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EnASR, REQUIRES_E2H1, FEAT_LS64_V),

	NEEDS_FEAT(SCTLR_EL2_nAA, FEAT_LSE2),

	NEEDS_FEAT_FLAG(SCTLR_EL2_LSMAOE	|

			SCTLR_EL2_nTLSMD,

			AS_RES1 | REQUIRES_E2H1, FEAT_LSMAOC),

	NEEDS_FEAT(SCTLR_EL2_EE, FEAT_MixedEnd),

	NEEDS_FEAT_FLAG(SCTLR_EL2_E0E, REQUIRES_E2H1, feat_mixedendel0),

	NEEDS_FEAT_FLAG(SCTLR_EL2_MSCEn, REQUIRES_E2H1, FEAT_MOPS),

	NEEDS_FEAT_FLAG(SCTLR_EL2_ATA0	|

			SCTLR_EL2_TCF0,

			REQUIRES_E2H1, FEAT_MTE2),

	NEEDS_FEAT(SCTLR_EL2_ATA	|

		   SCTLR_EL2_TCF,

		   FEAT_MTE2),

	NEEDS_FEAT(SCTLR_EL2_ITFSB, feat_mte_async),

	NEEDS_FEAT_FLAG(SCTLR_EL2_TCSO0, REQUIRES_E2H1, FEAT_MTE_STORE_ONLY),

	NEEDS_FEAT(SCTLR_EL2_TCSO,

		   FEAT_MTE_STORE_ONLY),

	NEEDS_FEAT(SCTLR_EL2_NMI	|

		   SCTLR_EL2_SPINTMASK,

		   FEAT_NMI),

	NEEDS_FEAT_FLAG(SCTLR_EL2_SPAN,	AS_RES1 | REQUIRES_E2H1, FEAT_PAN),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EPAN, REQUIRES_E2H1, FEAT_PAN3),

	NEEDS_FEAT(SCTLR_EL2_EnDA	|

		   SCTLR_EL2_EnDB	|

		   SCTLR_EL2_EnIA	|

		   SCTLR_EL2_EnIB,

		   feat_pauth),

	NEEDS_FEAT_FLAG(SCTLR_EL2_EnTP2, REQUIRES_E2H1, FEAT_SME),

	NEEDS_FEAT(SCTLR_EL2_EnRCTX, FEAT_SPECRES),

	NEEDS_FEAT(SCTLR_EL2_DSSBS, FEAT_SSBS),

	NEEDS_FEAT_FLAG(SCTLR_EL2_TIDCP, REQUIRES_E2H1, FEAT_TIDCP1),

	NEEDS_FEAT_FLAG(SCTLR_EL2_TWEDEL	|

			SCTLR_EL2_TWEDEn,

			REQUIRES_E2H1, FEAT_TWED),

	NEEDS_FEAT_FLAG(SCTLR_EL2_nTWE	|

			SCTLR_EL2_nTWI,

			AS_RES1 | REQUIRES_E2H1, FEAT_AA64EL2),

	NEEDS_FEAT_FLAG(SCTLR_EL2_UCI	|

			SCTLR_EL2_UCT	|

			SCTLR_EL2_DZE	|

			SCTLR_EL2_SA0,

			REQUIRES_E2H1, FEAT_AA64EL2),

	NEEDS_FEAT(SCTLR_EL2_WXN	|

		   SCTLR_EL2_I		|

		   SCTLR_EL2_SA		|

		   SCTLR_EL2_C		|

		   SCTLR_EL2_A		|

		   SCTLR_EL2_M,

		   FEAT_AA64EL2),

	FORCE_RES0(SCTLR_EL2_RES0),

	FORCE_RES1(SCTLR_EL2_RES1),

};



static const DECLARE_FEAT_MAP(sctlr_el2_desc, SCTLR_EL2,

			      sctlr_el2_feat_map, FEAT_AA64EL2);



static const struct reg_bits_to_feat_map mdcr_el2_feat_map[] = {

	NEEDS_FEAT(MDCR_EL2_EBWE, FEAT_Debugv8p9),

	NEEDS_FEAT(MDCR_EL2_TDOSA, FEAT_DoubleLock),
@@ -1247,6 +1325,7 @@ void __init check_feature_map(void) 
	check_reg_desc(&sctlr2_desc);

	check_reg_desc(&tcr2_el2_desc);

	check_reg_desc(&sctlr_el1_desc);

	check_reg_desc(&sctlr_el2_desc);

	check_reg_desc(&mdcr_el2_desc);

	check_reg_desc(&vtcr_el2_desc);

}
@@ -1443,6 +1522,9 @@ struct resx get_reg_fixed_bits(struct kvm *kvm, enum vcpu_sysreg reg) 
	case SCTLR_EL1:

		resx = compute_reg_resx_bits(kvm, &sctlr_el1_desc, 0, 0);

		break;

	case SCTLR_EL2:

		resx = compute_reg_resx_bits(kvm, &sctlr_el2_desc, 0, 0);

		break;

	case MDCR_EL2:

		resx = compute_reg_resx_bits(kvm, &mdcr_el2_desc, 0, 0);

		break;

arch/arm64/kvm/nested.c

+4 −0
Original line number Diff line number Diff line
@@ -1766,6 +1766,10 @@ int kvm_init_nv_sysregs(struct kvm_vcpu *vcpu) 
	resx = get_reg_fixed_bits(kvm, SCTLR_EL1);

	set_sysreg_masks(kvm, SCTLR_EL1, resx);



	/* SCTLR_EL2 */

	resx = get_reg_fixed_bits(kvm, SCTLR_EL2);

	set_sysreg_masks(kvm, SCTLR_EL2, resx);



	/* SCTLR2_ELx */

	resx = get_reg_fixed_bits(kvm, SCTLR2_EL1);

	set_sysreg_masks(kvm, SCTLR2_EL1, resx);