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 <oliver.upton@linux.dev>,
Zenghui Yu <yuzenghui@huawei.com>
Subject: [PATCH v2 09/16] KVM: arm64: Report faults from S1 walk setup at the expected start level
Date: Mon, 15 Sep 2025 12:44:44 +0100 [thread overview]
Message-ID: <20250915114451.660351-10-maz@kernel.org> (raw)
In-Reply-To: <20250915114451.660351-1-maz@kernel.org>
Translation faults from TTBR must be reported on the start level,
and not level-0. Enforcing this requires moving quite a lot of
code around so that the start level can be computed early enough
that it is usable.
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/at.c | 103 +++++++++++++++++++++++---------------------
1 file changed, 54 insertions(+), 49 deletions(-)
diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index fad9d7828d7b6..1230907d0aa0a 100644
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -154,9 +154,6 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
va55 = va & BIT(55);
- if (wi->regime == TR_EL2 && va55)
- goto addrsz;
-
wi->s2 = wi->regime == TR_EL10 && (hcr & (HCR_VM | HCR_DC));
switch (wi->regime) {
@@ -179,6 +176,46 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
BUG();
}
+ /* Someone was silly enough to encode TG0/TG1 differently */
+ if (va55 && wi->regime != TR_EL2) {
+ wi->txsz = FIELD_GET(TCR_T1SZ_MASK, tcr);
+ tg = FIELD_GET(TCR_TG1_MASK, tcr);
+
+ switch (tg << TCR_TG1_SHIFT) {
+ case TCR_TG1_4K:
+ wi->pgshift = 12; break;
+ case TCR_TG1_16K:
+ wi->pgshift = 14; break;
+ case TCR_TG1_64K:
+ default: /* IMPDEF: treat any other value as 64k */
+ wi->pgshift = 16; break;
+ }
+ } else {
+ wi->txsz = FIELD_GET(TCR_T0SZ_MASK, tcr);
+ tg = FIELD_GET(TCR_TG0_MASK, tcr);
+
+ switch (tg << TCR_TG0_SHIFT) {
+ case TCR_TG0_4K:
+ wi->pgshift = 12; break;
+ case TCR_TG0_16K:
+ wi->pgshift = 14; break;
+ case TCR_TG0_64K:
+ default: /* IMPDEF: treat any other value as 64k */
+ wi->pgshift = 16; break;
+ }
+ }
+
+ wi->pa52bit = has_52bit_pa(vcpu, wi, tcr);
+
+ ia_bits = get_ia_size(wi);
+
+ /* AArch64.S1StartLevel() */
+ stride = wi->pgshift - 3;
+ wi->sl = 3 - (((ia_bits - 1) - wi->pgshift) / stride);
+
+ if (wi->regime == TR_EL2 && va55)
+ goto addrsz;
+
tbi = (wi->regime == TR_EL2 ?
FIELD_GET(TCR_EL2_TBI, tcr) :
(va55 ?
@@ -248,46 +285,15 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
/* R_BVXDG */
wi->hpd |= (wi->poe || wi->e0poe);
- /* Someone was silly enough to encode TG0/TG1 differently */
- if (va55) {
- wi->txsz = FIELD_GET(TCR_T1SZ_MASK, tcr);
- tg = FIELD_GET(TCR_TG1_MASK, tcr);
-
- switch (tg << TCR_TG1_SHIFT) {
- case TCR_TG1_4K:
- wi->pgshift = 12; break;
- case TCR_TG1_16K:
- wi->pgshift = 14; break;
- case TCR_TG1_64K:
- default: /* IMPDEF: treat any other value as 64k */
- wi->pgshift = 16; break;
- }
- } else {
- wi->txsz = FIELD_GET(TCR_T0SZ_MASK, tcr);
- tg = FIELD_GET(TCR_TG0_MASK, tcr);
-
- switch (tg << TCR_TG0_SHIFT) {
- case TCR_TG0_4K:
- wi->pgshift = 12; break;
- case TCR_TG0_16K:
- wi->pgshift = 14; break;
- case TCR_TG0_64K:
- default: /* IMPDEF: treat any other value as 64k */
- wi->pgshift = 16; break;
- }
- }
-
/* R_PLCGL, R_YXNYW */
if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR2_EL1, ST, 48_47)) {
if (wi->txsz > 39)
- goto transfault_l0;
+ goto transfault;
} else {
if (wi->txsz > 48 || (BIT(wi->pgshift) == SZ_64K && wi->txsz > 47))
- goto transfault_l0;
+ goto transfault;
}
- wi->pa52bit = has_52bit_pa(vcpu, wi, tcr);
-
/* R_GTJBY, R_SXWGM */
switch (BIT(wi->pgshift)) {
case SZ_4K:
@@ -300,28 +306,22 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
}
if ((lva && wi->txsz < 12) || (!lva && wi->txsz < 16))
- goto transfault_l0;
-
- ia_bits = get_ia_size(wi);
+ goto transfault;
/* R_YYVYV, I_THCZK */
if ((!va55 && va > GENMASK(ia_bits - 1, 0)) ||
(va55 && va < GENMASK(63, ia_bits)))
- goto transfault_l0;
+ goto transfault;
/* I_ZFSYQ */
if (wi->regime != TR_EL2 &&
(tcr & (va55 ? TCR_EPD1_MASK : TCR_EPD0_MASK)))
- goto transfault_l0;
+ goto transfault;
/* R_BNDVG and following statements */
if (kvm_has_feat(vcpu->kvm, ID_AA64MMFR2_EL1, E0PD, IMP) &&
wi->as_el0 && (tcr & (va55 ? TCR_E0PD1 : TCR_E0PD0)))
- goto transfault_l0;
-
- /* AArch64.S1StartLevel() */
- stride = wi->pgshift - 3;
- wi->sl = 3 - (((ia_bits - 1) - wi->pgshift) / stride);
+ goto transfault;
ps = (wi->regime == TR_EL2 ?
FIELD_GET(TCR_EL2_PS_MASK, tcr) : FIELD_GET(TCR_IPS_MASK, tcr));
@@ -351,12 +351,17 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
return 0;
-addrsz: /* Address Size Fault level 0 */
+addrsz:
+ /*
+ * Address Size Fault level 0 to indicate it comes from TTBR.
+ * yes, this is an oddity.
+ */
fail_s1_walk(wr, ESR_ELx_FSC_ADDRSZ_L(0), false);
return -EFAULT;
-transfault_l0: /* Translation Fault level 0 */
- fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(0), false);
+transfault:
+ /* Translation Fault on start level */
+ fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(wi->sl), false);
return -EFAULT;
}
--
2.39.2
next prev parent reply other threads:[~2025-09-15 11:45 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-15 11:44 [PATCH v2 00/16] KVM: arm64: TTW reporting on SEA and 52bit PA in S1 PTW Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 01/16] KVM: arm64: Add helper computing the state of 52bit PA support Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 02/16] KVM: arm64: Account for 52bit when computing maximum OA Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 03/16] KVM: arm64: Compute 52bit TTBR address and alignment Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 04/16] KVM: arm64: Decouple output address from the PT descriptor Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 05/16] KVM: arm64: Pass the walk_info structure to compute_par_s1() Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 06/16] KVM: arm64: Compute shareability for LPA2 Marc Zyngier
2025-09-19 21:58 ` Oliver Upton
2025-09-15 11:44 ` [PATCH v2 07/16] KVM: arm64: Populate PAR_EL1 with 52bit addresses Marc Zyngier
2025-09-19 22:00 ` Oliver Upton
2025-09-20 9:27 ` Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 08/16] KVM: arm64: Expand valid block mappings to FEAT_LPA/LPA2 support Marc Zyngier
2025-09-15 11:44 ` Marc Zyngier [this message]
2025-09-15 11:44 ` [PATCH v2 10/16] KVM: arm64: Allow use of S1 PTW for non-NV vcpus Marc Zyngier
2025-09-19 22:27 ` Oliver Upton
2025-09-20 9:24 ` Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 11/16] KVM: arm64: Allow EL1 control registers to be accessed from the CPU state Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 12/16] KVM: arm64: Don't switch MMU on translation from non-NV context Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 13/16] KVM: arm64: Add filtering hook to S1 page table walk Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 14/16] KVM: arm64: Add S1 IPA to page table level walker Marc Zyngier
2025-09-19 22:31 ` Oliver Upton
2025-09-15 11:44 ` [PATCH v2 15/16] KVM: arm64: Populate level on S1PTW SEA injection Marc Zyngier
2025-09-15 11:44 ` [PATCH v2 16/16] KVM: arm64: selftest: Expand external_aborts test to look for TTW levels Marc Zyngier
2025-09-19 22:36 ` Oliver Upton
2025-09-19 22:37 ` [PATCH v2 00/16] KVM: arm64: TTW reporting on SEA and 52bit PA in S1 PTW Oliver Upton
2025-09-21 11:00 ` Marc Zyngier
2025-09-21 10:57 ` Marc Zyngier
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