diff options
| author | Anshuman Khandual <anshuman.khandual@arm.com> | 2021-08-11 16:41:15 +0530 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-08-11 16:00:04 +0100 |
| commit | 5e5df9571c319fb107d7a523cc96fcc99961ee70 (patch) | |
| tree | 5781052aebcf59f3678d6ca789d8d7c31e11bf87 /arch/arm64/kvm | |
| parent | b31578f627177bda5c16894e3170a7a6a1236136 (diff) | |
KVM: arm64: Restrict IPA size to maximum 48 bits on 4K and 16K page size
Even though ID_AA64MMFR0.PARANGE reports 52 bit PA size support, it cannot
be enabled as guest IPA size on 4K or 16K page size configurations. Hence
kvm_ipa_limit must be restricted to 48 bits. This change achieves required
IPA capping.
Before the commit c9b69a0cf0b4 ("KVM: arm64: Don't constrain maximum IPA
size based on host configuration"), the problem here would have been just
latent via PHYS_MASK_SHIFT (which earlier in turn capped kvm_ipa_limit),
which remains capped at 48 bits on 4K and 16K configs.
Cc: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: kvmarm@lists.cs.columbia.edu
Cc: linux-kernel@vger.kernel.org
Fixes: c9b69a0cf0b4 ("KVM: arm64: Don't constrain maximum IPA size based on host configuration")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1628680275-16578-1-git-send-email-anshuman.khandual@arm.com
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/reset.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 20588220fe66..18ffc6ad67b8 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -317,6 +317,14 @@ int kvm_set_ipa_limit(void) mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); parange = cpuid_feature_extract_unsigned_field(mmfr0, ID_AA64MMFR0_PARANGE_SHIFT); + /* + * IPA size beyond 48 bits could not be supported + * on either 4K or 16K page size. Hence let's cap + * it to 48 bits, in case it's reported as larger + * on the system. + */ + if (PAGE_SIZE != SZ_64K) + parange = min(parange, (unsigned int)ID_AA64MMFR0_PARANGE_48); /* * Check with ARMv8.5-GTG that our PAGE_SIZE is supported at |