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| author | Will Deacon <will@kernel.org> | 2022-11-10 19:02:55 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-11-11 17:19:35 +0000 |
| commit | 73f38ef2ae531b180685173e0923225551434fcb (patch) | |
| tree | c67b03ec07350daca0afc1f04806115d3f5da43f /arch/arm64/kvm/arm.c | |
| parent | fe41a7f8c0ee3ee2f682f8c28c7e1c5ff2be8a79 (diff) | |
| download | linux-73f38ef2ae531b180685173e0923225551434fcb.tar.bz2 | |
KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2
Sharing 'kvm_arm_vmid_bits' between EL1 and EL2 allows the host to
modify the variable arbitrarily, potentially leading to all sorts of
shenanians as this is used to configure the VTTBR register for the
guest stage-2.
In preparation for unmapping host sections entirely from EL2, maintain
a copy of 'kvm_arm_vmid_bits' in the pKVM hypervisor and initialise it
from the host value while it is still trusted.
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-23-will@kernel.org
Diffstat (limited to 'arch/arm64/kvm/arm.c')
| -rw-r--r-- | arch/arm64/kvm/arm.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 25467f24803d..1d4b8122d010 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1893,6 +1893,7 @@ static void kvm_hyp_init_symbols(void) kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); kvm_nvhe_sym(__icache_flags) = __icache_flags; + kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; } static int kvm_hyp_init_protection(u32 hyp_va_bits) |