diff options
| author | Fuad Tabba <tabba@google.com> | 2026-04-24 09:49:03 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2026-04-24 12:03:57 +0100 |
| commit | 7fe2cd4e1a3ad230d8fcc00cc99c4bcce4412a75 (patch) | |
| tree | 358aad045abce24cfac0df597eb22be48c781701 | |
| parent | 480ea48cad873b49a1fabd07c0847c3cf1c32286 (diff) | |
KVM: arm64: Fix FEAT_Debugv8p9 to check DebugVer, not PMUVer
FEAT_Debugv8p9 is incorrectly defined against ID_AA64DFR0_EL1.PMUVer
instead of ID_AA64DFR0_EL1.DebugVer. All three consumers of the macro
gate features that are architecturally tied to FEAT_Debugv8p9
(DebugVer = 0b1011, DDI0487 M.b A2.2.10):
- HDFGRTR2_EL2.nMDSELR_EL1, HDFGWTR2_EL2.nMDSELR_EL1: MDSELR_EL1
is present only when FEAT_Debugv8p9 is implemented (D24.3.21).
- MDCR_EL2.EBWE: the Extended Breakpoint and Watchpoint Enable bit
is RES0 unless FEAT_Debugv8p9 is implemented (D24.3.17).
Neither register has any dependency on PMUVer.
FEAT_Debugv8p9 and FEAT_PMUv3p9 are independent. Per DDI0487 M.b
A2.2.10, FEAT_Debugv8p9 is unconditionally mandatory from Armv8.9,
whereas FEAT_PMUv3p9 is mandatory only when FEAT_PMUv3 is implemented.
An Armv8.9 CPU without a PMU has DebugVer = 0b1011 but PMUVer = 0b0000,
so the wrong field check would cause KVM to incorrectly treat EBWE and
MDSELR_EL1 as RES0 on such hardware.
Fixes: 4bc0fe089840 ("KVM: arm64: Add sanitisation for FEAT_FGT2 registers")
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260424084908.370776-2-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
| -rw-r--r-- | arch/arm64/kvm/config.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kvm/config.c b/arch/arm64/kvm/config.c index f35b8dddd7c1..093290b366e6 100644 --- a/arch/arm64/kvm/config.c +++ b/arch/arm64/kvm/config.c @@ -192,7 +192,7 @@ struct reg_feat_map_desc { #define FEAT_SRMASK ID_AA64MMFR4_EL1, SRMASK, IMP #define FEAT_PoPS ID_AA64MMFR4_EL1, PoPS, IMP #define FEAT_PFAR ID_AA64PFR1_EL1, PFAR, IMP -#define FEAT_Debugv8p9 ID_AA64DFR0_EL1, PMUVer, V3P9 +#define FEAT_Debugv8p9 ID_AA64DFR0_EL1, DebugVer, V8P9 #define FEAT_PMUv3_SS ID_AA64DFR0_EL1, PMSS, IMP #define FEAT_SEBEP ID_AA64DFR0_EL1, SEBEP, IMP #define FEAT_EBEP ID_AA64DFR1_EL1, EBEP, IMP |