Commit ad90512f authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: Add REQUIRES_E2H1 constraint as configuration flags 



A bunch of EL2 configuration are very similar to their EL1 counterpart,
with the added constraint that HCR_EL2.E2H being 1.

For us, this means HCR_EL2.E2H being RES1, which is something we can
statically evaluate.

Add a REQUIRES_E2H1 constraint, which allows us to express conditions
in a much simpler way (without extra code). Existing occurrences are
converted, before we add a lot more.

Reviewed-by: default avatarFuad Tabba <tabba@google.com>
Tested-by: default avatarFuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260202184329.2724080-12-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 8d944582

arch/arm64/kvm/config.c

+14 −24
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ struct reg_bits_to_feat_map { 
#define	FIXED_VALUE	BIT(2)	/* RAZ/WI or RAO/WI in KVM */

#define	MASKS_POINTER	BIT(3)	/* Pointer to fgt_masks struct instead of bits */

#define	AS_RES1		BIT(4)	/* RES1 when not supported */

#define	REQUIRES_E2H1	BIT(5)	/* Add HCR_EL2.E2H RES1 as a pre-condition */



	unsigned long	flags;
@@ -311,21 +312,6 @@ static bool feat_trbe_mpam(struct kvm *kvm) 
		(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_EL1_MPAM));

}



static bool feat_asid2_e2h1(struct kvm *kvm)

{

	return kvm_has_feat(kvm, FEAT_ASID2) && !kvm_has_feat(kvm, FEAT_E2H0);

}



static bool feat_d128_e2h1(struct kvm *kvm)

{

	return kvm_has_feat(kvm, FEAT_D128) && !kvm_has_feat(kvm, FEAT_E2H0);

}



static bool feat_mec_e2h1(struct kvm *kvm)

{

	return kvm_has_feat(kvm, FEAT_MEC) && !kvm_has_feat(kvm, FEAT_E2H0);

}



static bool feat_ebep_pmuv3_ss(struct kvm *kvm)

{

	return kvm_has_feat(kvm, FEAT_EBEP) || kvm_has_feat(kvm, FEAT_PMUv3_SS);
@@ -1045,15 +1031,15 @@ static const DECLARE_FEAT_MAP(sctlr2_desc, SCTLR2_EL1, 
			      sctlr2_feat_map, FEAT_SCTLR2);



static const struct reg_bits_to_feat_map tcr2_el2_feat_map[] = {

	NEEDS_FEAT(TCR2_EL2_FNG1	|

	NEEDS_FEAT_FLAG(TCR2_EL2_FNG1	|

			TCR2_EL2_FNG0	|

			TCR2_EL2_A2,

		   feat_asid2_e2h1),

	NEEDS_FEAT(TCR2_EL2_DisCH1	|

			REQUIRES_E2H1, FEAT_ASID2),

	NEEDS_FEAT_FLAG(TCR2_EL2_DisCH1	|

			TCR2_EL2_DisCH0	|

			TCR2_EL2_D128,

		   feat_d128_e2h1),

	NEEDS_FEAT(TCR2_EL2_AMEC1, feat_mec_e2h1),

			REQUIRES_E2H1, FEAT_D128),

	NEEDS_FEAT_FLAG(TCR2_EL2_AMEC1, REQUIRES_E2H1, FEAT_MEC),

	NEEDS_FEAT(TCR2_EL2_AMEC0, FEAT_MEC),

	NEEDS_FEAT(TCR2_EL2_HAFT, FEAT_HAFT),

	NEEDS_FEAT(TCR2_EL2_PTTWI	|
@@ -1284,6 +1270,7 @@ static struct resx compute_resx_bits(struct kvm *kvm, 
				     unsigned long require,

				     unsigned long exclude)

{

	bool e2h0 = kvm_has_feat(kvm, FEAT_E2H0);

	struct resx resx = {};



	for (int i = 0; i < map_size; i++) {
@@ -1306,6 +1293,9 @@ static struct resx compute_resx_bits(struct kvm *kvm, 
			match = idreg_feat_match(kvm, &map[i]);

		}



		if (map[i].flags & REQUIRES_E2H1)

			match &= !e2h0;



		if (!match) {

			if (map[i].flags & AS_RES1)

				resx.res1 |= reg_feat_map_bits(&map[i]);