From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org,
kvm@vger.kernel.org
Cc: Joey Gouly <joey.gouly@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Oliver Upton <oupton@kernel.org>,
Zenghui Yu <yuzenghui@huawei.com>, Fuad Tabba <tabba@google.com>,
Will Deacon <will@kernel.org>,
Catalin Marinas <catalin.marinas@arm.com>
Subject: [PATCH 11/20] KVM: arm64: Add REQUIRES_E2H1 constraint as configuration flags
Date: Mon, 26 Jan 2026 12:16:45 +0000 [thread overview]
Message-ID: <20260126121655.1641736-12-maz@kernel.org> (raw)
In-Reply-To: <20260126121655.1641736-1-maz@kernel.org>
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.
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/config.c | 38 ++++++++++++++------------------------
1 file changed, 14 insertions(+), 24 deletions(-)
diff --git a/arch/arm64/kvm/config.c b/arch/arm64/kvm/config.c
index 4fac04d3132c0..1990cebc77c66 100644
--- a/arch/arm64/kvm/config.c
+++ b/arch/arm64/kvm/config.c
@@ -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 |
- TCR2_EL2_FNG0 |
- TCR2_EL2_A2,
- feat_asid2_e2h1),
- NEEDS_FEAT(TCR2_EL2_DisCH1 |
- TCR2_EL2_DisCH0 |
- TCR2_EL2_D128,
- feat_d128_e2h1),
- NEEDS_FEAT(TCR2_EL2_AMEC1, feat_mec_e2h1),
+ NEEDS_FEAT_FLAG(TCR2_EL2_FNG1 |
+ TCR2_EL2_FNG0 |
+ TCR2_EL2_A2,
+ REQUIRES_E2H1, FEAT_ASID2),
+ NEEDS_FEAT_FLAG(TCR2_EL2_DisCH1 |
+ TCR2_EL2_DisCH0 |
+ TCR2_EL2_D128,
+ 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 |
@@ -1285,6 +1271,7 @@ 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++) {
@@ -1307,6 +1294,9 @@ 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]);
--
2.47.3
next prev parent reply other threads:[~2026-01-26 12:18 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-26 12:16 [PATCH 00/20] KVM: arm64: Generalise RESx handling Marc Zyngier
2026-01-26 12:16 ` [PATCH 01/20] arm64: Convert SCTLR_EL2 to sysreg infrastructure Marc Zyngier
2026-01-26 17:53 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 02/20] KVM: arm64: Remove duplicate configuration for SCTLR_EL1.{EE,E0E} Marc Zyngier
2026-01-26 18:04 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 03/20] KVM: arm64: Introduce standalone FGU computing primitive Marc Zyngier
2026-01-26 18:35 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 04/20] KVM: arm64: Introduce data structure tracking both RES0 and RES1 bits Marc Zyngier
2026-01-26 18:54 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 05/20] KVM: arm64: Extend unified RESx handling to runtime sanitisation Marc Zyngier
2026-01-26 19:15 ` Fuad Tabba
2026-01-27 10:52 ` Marc Zyngier
2026-01-26 12:16 ` [PATCH 06/20] KVM: arm64: Inherit RESx bits from FGT register descriptors Marc Zyngier
2026-01-27 15:21 ` Joey Gouly
2026-01-27 17:58 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 07/20] KVM: arm64: Allow RES1 bits to be inferred from configuration Marc Zyngier
2026-01-27 15:26 ` Joey Gouly
2026-01-27 17:58 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 08/20] KVM: arm64: Correctly handle SCTLR_EL1 RES1 bits for unsupported features Marc Zyngier
2026-01-27 18:06 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 09/20] KVM: arm64: Convert HCR_EL2.RW to AS_RES1 Marc Zyngier
2026-01-27 18:09 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 10/20] KVM: arm64: Simplify FIXED_VALUE handling Marc Zyngier
2026-01-27 18:20 ` Fuad Tabba
2026-01-26 12:16 ` Marc Zyngier [this message]
2026-01-27 18:28 ` [PATCH 11/20] KVM: arm64: Add REQUIRES_E2H1 constraint as configuration flags Fuad Tabba
2026-01-26 12:16 ` [PATCH 12/20] KVM: arm64: Add RESx_WHEN_E2Hx constraints " Marc Zyngier
2026-01-28 17:43 ` Fuad Tabba
2026-01-29 10:14 ` Marc Zyngier
2026-01-29 10:30 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 13/20] KVM: arm64: Move RESx into individual register descriptors Marc Zyngier
2026-01-29 16:29 ` Fuad Tabba
2026-01-29 17:19 ` Marc Zyngier
2026-01-29 17:39 ` Fuad Tabba
2026-01-29 18:07 ` Marc Zyngier
2026-01-29 18:13 ` Fuad Tabba
2026-01-30 9:06 ` Marc Zyngier
2026-01-26 12:16 ` [PATCH 14/20] KVM: arm64: Simplify handling of HCR_EL2.E2H RESx Marc Zyngier
2026-01-29 16:41 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 15/20] KVM: arm64: Get rid of FIXED_VALUE altogether Marc Zyngier
2026-01-29 16:54 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 16/20] KVM: arm64: Simplify handling of full register invalid constraint Marc Zyngier
2026-01-29 17:34 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 17/20] KVM: arm64: Remove all traces of FEAT_TME Marc Zyngier
2026-01-29 17:43 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 18/20] KVM: arm64: Remove all traces of HCR_EL2.MIOCNCE Marc Zyngier
2026-01-29 17:51 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 19/20] KVM: arm64: Add sanitisation to SCTLR_EL2 Marc Zyngier
2026-01-29 18:11 ` Fuad Tabba
2026-01-26 12:16 ` [PATCH 20/20] KVM: arm64: Add debugfs file dumping computed RESx values Marc Zyngier
2026-02-02 8:59 ` Fuad Tabba
2026-02-02 9:14 ` Marc Zyngier
2026-02-02 9:57 ` Fuad Tabba
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