diff options
| 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/include/asm/kvm_hyp.h | |
| 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/include/asm/kvm_hyp.h')
| -rw-r--r-- | arch/arm64/include/asm/kvm_hyp.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index fd99cf09972d..6797eafe7890 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -124,4 +124,6 @@ extern u64 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val); extern u64 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val); extern unsigned long kvm_nvhe_sym(__icache_flags); +extern unsigned int kvm_nvhe_sym(kvm_arm_vmid_bits); + #endif /* __ARM64_KVM_HYP_H__ */ |