Merge branch 'kvm-arm64/nv-xnx-haf' into kvmarm/next

* kvm-arm64/nv-xnx-haf: (22 commits)
  : Support for FEAT_XNX and FEAT_HAF in nested
  :
  : Add support for a couple of MMU-related features that weren't
  : implemented by KVM's software page table walk:
  :
  :  - FEAT_XNX: Allows the hypervisor to describe execute permissions
  :    separately for EL0 and EL1
  :
  :  - FEAT_HAF: Hardware update of the Access Flag, which in the context of
  :    nested means software walkers must also set the Access Flag.
  :
  : The series also adds some basic support for testing KVM's emulation of
  : the AT instruction, including the implementation detail that AT sets the
  : Access Flag in KVM.
  KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS
  KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2
  KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX}
  KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected"
  KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot()
  KVM: arm64: Add endian casting to kvm_swap_s[12]_desc()
  KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n
  KVM: arm64: selftests: Add test for AT emulation
  KVM: arm64: nv: Expose hardware access flag management to NV guests
  KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW
  KVM: arm64: Implement HW access flag management in stage-1 SW PTW
  KVM: arm64: Propagate PTW errors up to AT emulation
  KVM: arm64: Add helper for swapping guest descriptor
  KVM: arm64: nv: Use pgtable definitions in stage-2 walk
  KVM: arm64: Handle endianness in read helper for emulated PTW
  KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW
  KVM: arm64: Call helper for reading descriptors directly
  KVM: arm64: nv: Advertise support for FEAT_XNX
  KVM: arm64: Teach ptdump about FEAT_XNX permissions
  KVM: arm64: nv: Forward FEAT_XNX permissions to the shadow stage-2
  ...

Signed-off-by: Oliver Upton <oupton@kernel.org>
This commit is contained in:
Oliver Upton
2025-12-01 00:47:41 -08:00
16 changed files with 607 additions and 95 deletions

View File

@@ -661,11 +661,37 @@ void kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu,
#define KVM_S2_MEMATTR(pgt, attr) PAGE_S2_MEMATTR(attr, stage2_has_fwb(pgt))
static int stage2_set_xn_attr(enum kvm_pgtable_prot prot, kvm_pte_t *attr)
{
bool px, ux;
u8 xn;
px = prot & KVM_PGTABLE_PROT_PX;
ux = prot & KVM_PGTABLE_PROT_UX;
if (!cpus_have_final_cap(ARM64_HAS_XNX) && px != ux)
return -EINVAL;
if (px && ux)
xn = 0b00;
else if (!px && ux)
xn = 0b01;
else if (!px && !ux)
xn = 0b10;
else
xn = 0b11;
*attr &= ~KVM_PTE_LEAF_ATTR_HI_S2_XN;
*attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_HI_S2_XN, xn);
return 0;
}
static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot prot,
kvm_pte_t *ptep)
{
kvm_pte_t attr;
u32 sh = KVM_PTE_LEAF_ATTR_LO_S2_SH_IS;
int r;
switch (prot & (KVM_PGTABLE_PROT_DEVICE |
KVM_PGTABLE_PROT_NORMAL_NC)) {
@@ -685,8 +711,9 @@ static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot p
attr = KVM_S2_MEMATTR(pgt, NORMAL);
}
if (!(prot & KVM_PGTABLE_PROT_X))
attr |= KVM_PTE_LEAF_ATTR_HI_S2_XN;
r = stage2_set_xn_attr(prot, &attr);
if (r)
return r;
if (prot & KVM_PGTABLE_PROT_R)
attr |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R;
@@ -715,8 +742,20 @@ enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte)
prot |= KVM_PGTABLE_PROT_R;
if (pte & KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W)
prot |= KVM_PGTABLE_PROT_W;
if (!(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN))
prot |= KVM_PGTABLE_PROT_X;
switch (FIELD_GET(KVM_PTE_LEAF_ATTR_HI_S2_XN, pte)) {
case 0b00:
prot |= KVM_PGTABLE_PROT_PX | KVM_PGTABLE_PROT_UX;
break;
case 0b01:
prot |= KVM_PGTABLE_PROT_UX;
break;
case 0b11:
prot |= KVM_PGTABLE_PROT_PX;
break;
default:
break;
}
return prot;
}
@@ -1290,9 +1329,9 @@ bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr,
int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
enum kvm_pgtable_prot prot, enum kvm_pgtable_walk_flags flags)
{
int ret;
kvm_pte_t xn = 0, set = 0, clr = 0;
s8 level;
kvm_pte_t set = 0, clr = 0;
int ret;
if (prot & KVM_PTE_LEAF_ATTR_HI_SW)
return -EINVAL;
@@ -1303,8 +1342,12 @@ int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
if (prot & KVM_PGTABLE_PROT_W)
set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W;
if (prot & KVM_PGTABLE_PROT_X)
clr |= KVM_PTE_LEAF_ATTR_HI_S2_XN;
ret = stage2_set_xn_attr(prot, &xn);
if (ret)
return ret;
set |= xn & KVM_PTE_LEAF_ATTR_HI_S2_XN;
clr |= ~xn & KVM_PTE_LEAF_ATTR_HI_S2_XN;
ret = stage2_update_leaf_attrs(pgt, addr, 1, set, clr, NULL, &level, flags);
if (!ret || ret == -EAGAIN)