github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-27 00:22:00 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

KVM: arm64: nv: Snapshot S1 ASID tagging information during walk

Browse Source 
We currently completely ignore any sort of ASID tagging during a S1
walk, as AT doesn't care about it.

However, such information is required if we are going to create
anything that looks like a TLB from this walk.

Let's capture it both the nG and ASID information while walking
the page tables.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20250514103501.2225951-5-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
This commit is contained in:
Marc Zyngier 2025-05-14 11:34:47 +01:00
parent 34fa9dece5
commit a0ec2b822c
2 changed files with 29 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/arm64/include/asm/kvm_nested.h
View File

@ -274,6 +274,8 @@ struct s1_walk_result {
u64 pa;
s8 level;
u8 APTable;
bool nG;
u16 asid;
bool UXNTable;
bool PXNTable;
bool uwxn;

27
arch/arm64/kvm/at.c
View File

@ -414,6 +414,33 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
wr->pa = desc & GENMASK(47, va_bottom);
wr->pa |= va & GENMASK_ULL(va_bottom - 1, 0);
wr->nG = (wi->regime != TR_EL2) && (desc & PTE_NG);
if (wr->nG) {
u64 asid_ttbr, tcr;
switch (wi->regime) {
case TR_EL10:
tcr = vcpu_read_sys_reg(vcpu, TCR_EL1);
asid_ttbr = ((tcr & TCR_A1) ?
vcpu_read_sys_reg(vcpu, TTBR1_EL1) :
vcpu_read_sys_reg(vcpu, TTBR0_EL1));
break;
case TR_EL20:
tcr = vcpu_read_sys_reg(vcpu, TCR_EL2);
asid_ttbr = ((tcr & TCR_A1) ?
vcpu_read_sys_reg(vcpu, TTBR1_EL2) :
vcpu_read_sys_reg(vcpu, TTBR0_EL2));
break;
default:
BUG();
}
wr->asid = FIELD_GET(TTBR_ASID_MASK, asid_ttbr);
if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR0_EL1, ASIDBITS, 16) ||
!(tcr & TCR_ASID16))
wr->asid &= GENMASK(7, 0);
}
return 0;
addrsz: