diff options
| author | Marc Zyngier <maz@kernel.org> | 2025-08-25 11:28:19 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2025-09-20 11:05:13 +0100 |
| commit | 0c5471408cb5c518bce76b851aff89719283a428 (patch) | |
| tree | 1fd8e78ecec2f648695f163f4cd51abf3a782828 | |
| parent | 61b0280a670bdbb3a209ae474625f387788af0a8 (diff) | |
KVM: arm64: Add filtering hook to S1 page table walk
Add a filtering hook that can get called on each level of the
walk, and providing access to the full state.
Crucially, this is called *before* the access is made, so that
it is possible to track down the level of a faulting access.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/include/asm/kvm_nested.h | 14 | ||||
| -rw-r--r-- | arch/arm64/kvm/at.c | 11 |
2 files changed, 25 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index f3135ded47b7..cce0e4cb5448 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -288,7 +288,21 @@ enum trans_regime { TR_EL2, }; +struct s1_walk_info; + +struct s1_walk_context { + struct s1_walk_info *wi; + u64 table_ipa; + int level; +}; + +struct s1_walk_filter { + int (*fn)(struct s1_walk_context *, void *); + void *priv; +}; + struct s1_walk_info { + struct s1_walk_filter *filter; u64 baddr; enum trans_regime regime; unsigned int max_oa_bits; diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c index c06a8e831f33..b70b777a3c20 100644 --- a/arch/arm64/kvm/at.c +++ b/arch/arm64/kvm/at.c @@ -404,6 +404,17 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi, ipa = kvm_s2_trans_output(&s2_trans); } + if (wi->filter) { + ret = wi->filter->fn(&(struct s1_walk_context) + { + .wi = wi, + .table_ipa = baddr, + .level = level, + }, wi->filter->priv); + if (ret) + return ret; + } + ret = kvm_read_guest(vcpu->kvm, ipa, &desc, sizeof(desc)); if (ret) { fail_s1_walk(wr, ESR_ELx_FSC_SEA_TTW(level), false); |