Re: [PATCH 08/20] KVM: arm64: Correctly handle SCTLR_EL1 RES1 bits for unsupported features
From: Fuad Tabba <tabba@google.com>
Date: 2026-01-27 18:07:04
Also in:
kvm, kvmarm
Hi Marc, On Mon, 26 Jan 2026 at 12:17, Marc Zyngier [off-list ref] wrote:
A bunch of SCTLR_EL1 bits must be set to RES1 when the controlling
nit: controlling
feature is not present. Add the AS_RES1 qualifier where needed. Signed-off-by: Marc Zyngier <maz@kernel.org>
Otherwise, it matches the Arm Arm. Reviewed-by: Fuad Tabba <tabba@google.com> Cheers, /fuad
quoted hunk ↗ jump to hunk
--- arch/arm64/kvm/config.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)diff --git a/arch/arm64/kvm/config.c b/arch/arm64/kvm/config.c index 6a4674fabf865..68ed5af2b4d53 100644 --- a/arch/arm64/kvm/config.c +++ b/arch/arm64/kvm/config.c@@ -1085,27 +1085,28 @@ static const DECLARE_FEAT_MAP(tcr2_el2_desc, TCR2_EL2, tcr2_el2_feat_map, FEAT_TCR2); static const struct reg_bits_to_feat_map sctlr_el1_feat_map[] = { - NEEDS_FEAT(SCTLR_EL1_CP15BEN | - SCTLR_EL1_ITD | - SCTLR_EL1_SED, - FEAT_AA32EL0), + NEEDS_FEAT(SCTLR_EL1_CP15BEN, FEAT_AA32EL0), + NEEDS_FEAT_FLAG(SCTLR_EL1_ITD | + SCTLR_EL1_SED, + AS_RES1, FEAT_AA32EL0), NEEDS_FEAT(SCTLR_EL1_BT0 | SCTLR_EL1_BT1, FEAT_BTI), NEEDS_FEAT(SCTLR_EL1_CMOW, FEAT_CMOW), - NEEDS_FEAT(SCTLR_EL1_TSCXT, feat_csv2_2_csv2_1p2), - NEEDS_FEAT(SCTLR_EL1_EIS | - SCTLR_EL1_EOS, - FEAT_ExS), + NEEDS_FEAT_FLAG(SCTLR_EL1_TSCXT, + AS_RES1, feat_csv2_2_csv2_1p2), + NEEDS_FEAT_FLAG(SCTLR_EL1_EIS | + SCTLR_EL1_EOS, + AS_RES1, FEAT_ExS), NEEDS_FEAT(SCTLR_EL1_EnFPM, FEAT_FPMR), NEEDS_FEAT(SCTLR_EL1_IESB, FEAT_IESB), NEEDS_FEAT(SCTLR_EL1_EnALS, FEAT_LS64), NEEDS_FEAT(SCTLR_EL1_EnAS0, FEAT_LS64_ACCDATA), NEEDS_FEAT(SCTLR_EL1_EnASR, FEAT_LS64_V), NEEDS_FEAT(SCTLR_EL1_nAA, FEAT_LSE2), - NEEDS_FEAT(SCTLR_EL1_LSMAOE | - SCTLR_EL1_nTLSMD, - FEAT_LSMAOC), + NEEDS_FEAT_FLAG(SCTLR_EL1_LSMAOE | + SCTLR_EL1_nTLSMD, + AS_RES1, FEAT_LSMAOC), NEEDS_FEAT(SCTLR_EL1_EE, FEAT_MixedEnd), NEEDS_FEAT(SCTLR_EL1_E0E, feat_mixedendel0), NEEDS_FEAT(SCTLR_EL1_MSCEn, FEAT_MOPS),@@ -1121,7 +1122,8 @@ static const struct reg_bits_to_feat_map sctlr_el1_feat_map[] = { NEEDS_FEAT(SCTLR_EL1_NMI | SCTLR_EL1_SPINTMASK, FEAT_NMI), - NEEDS_FEAT(SCTLR_EL1_SPAN, FEAT_PAN), + NEEDS_FEAT_FLAG(SCTLR_EL1_SPAN, + AS_RES1, FEAT_PAN), NEEDS_FEAT(SCTLR_EL1_EPAN, FEAT_PAN3), NEEDS_FEAT(SCTLR_EL1_EnDA | SCTLR_EL1_EnDB | --2.47.3