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Marc Zyngier
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Merge branch kvm-arm64/s2-ptdump into kvmarm-master/next
* kvm-arm64/s2-ptdump: : . : Stage-2 page table dumper, reusing the main ptdump infrastructure, : courtesy of Sebastian Ene. From the cover letter: : : "This series extends the ptdump support to allow dumping the guest : stage-2 pagetables. When CONFIG_PTDUMP_STAGE2_DEBUGFS is enabled, ptdump : registers the new following files under debugfs: : - /sys/debug/kvm/<guest_id>/stage2_page_tables : - /sys/debug/kvm/<guest_id>/stage2_levels : - /sys/debug/kvm/<guest_id>/ipa_range : : This allows userspace tools (eg. cat) to dump the stage-2 pagetables by : reading the 'stage2_page_tables' file. : [...]" : . KVM: arm64: Register ptdump with debugfs on guest creation arm64: ptdump: Don't override the level when operating on the stage-2 tables arm64: ptdump: Use the ptdump description from a local context arm64: ptdump: Expose the attribute parsing functionality KVM: arm64: Move pagetable definitions to common header Signed-off-by: Marc Zyngier <[email protected]>
2 parents 2e0f239 + 7c4f735 commit f625469

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‎arch/arm64/include/asm/kvm_mmu.h

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -352,5 +352,11 @@ static inline bool kvm_is_nested_s2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu)
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return &kvm->arch.mmu != mmu;
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}
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#ifdef CONFIG_PTDUMP_STAGE2_DEBUGFS
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void kvm_s2_ptdump_create_debugfs(struct kvm *kvm);
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#else
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static inline void kvm_s2_ptdump_create_debugfs(struct kvm *kvm) {}
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#endif /* CONFIG_PTDUMP_STAGE2_DEBUGFS */
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#endif /* __ASSEMBLY__ */
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#endif /* __ARM64_KVM_MMU_H__ */

‎arch/arm64/include/asm/kvm_pgtable.h

Lines changed: 42 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -59,6 +59,48 @@ typedef u64 kvm_pte_t;
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#define KVM_PHYS_INVALID (-1ULL)
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#define KVM_PTE_LEAF_ATTR_LO GENMASK(11, 2)
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#define KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX GENMASK(4, 2)
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#define KVM_PTE_LEAF_ATTR_LO_S1_AP GENMASK(7, 6)
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#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RO \
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({ cpus_have_final_cap(ARM64_KVM_HVHE) ? 2 : 3; })
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#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RW \
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({ cpus_have_final_cap(ARM64_KVM_HVHE) ? 0 : 1; })
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#define KVM_PTE_LEAF_ATTR_LO_S1_SH GENMASK(9, 8)
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#define KVM_PTE_LEAF_ATTR_LO_S1_SH_IS 3
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#define KVM_PTE_LEAF_ATTR_LO_S1_AF BIT(10)
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#define KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR GENMASK(5, 2)
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#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R BIT(6)
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#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W BIT(7)
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#define KVM_PTE_LEAF_ATTR_LO_S2_SH GENMASK(9, 8)
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#define KVM_PTE_LEAF_ATTR_LO_S2_SH_IS 3
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#define KVM_PTE_LEAF_ATTR_LO_S2_AF BIT(10)
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#define KVM_PTE_LEAF_ATTR_HI GENMASK(63, 50)
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#define KVM_PTE_LEAF_ATTR_HI_SW GENMASK(58, 55)
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#define KVM_PTE_LEAF_ATTR_HI_S1_XN BIT(54)
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#define KVM_PTE_LEAF_ATTR_HI_S2_XN BIT(54)
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#define KVM_PTE_LEAF_ATTR_HI_S1_GP BIT(50)
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#define KVM_PTE_LEAF_ATTR_S2_PERMS (KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R | \
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KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W | \
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KVM_PTE_LEAF_ATTR_HI_S2_XN)
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#define KVM_INVALID_PTE_OWNER_MASK GENMASK(9, 2)
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#define KVM_MAX_OWNER_ID 1
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/*
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* Used to indicate a pte for which a 'break-before-make' sequence is in
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* progress.
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*/
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#define KVM_INVALID_PTE_LOCKED BIT(10)
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static inline bool kvm_pte_valid(kvm_pte_t pte)
63105
{
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return pte & KVM_PTE_VALID;

‎arch/arm64/include/asm/ptdump.h

Lines changed: 42 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -5,6 +5,8 @@
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#ifndef __ASM_PTDUMP_H
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#define __ASM_PTDUMP_H
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8+
#include <linux/ptdump.h>
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#ifdef CONFIG_PTDUMP_CORE
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#include <linux/mm_types.h>
@@ -21,14 +23,53 @@ struct ptdump_info {
2123
unsigned long base_addr;
2224
};
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26+
struct ptdump_prot_bits {
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u64 mask;
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u64 val;
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const char *set;
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const char *clear;
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};
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struct ptdump_pg_level {
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const struct ptdump_prot_bits *bits;
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char name[4];
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int num;
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u64 mask;
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};
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/*
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* The page dumper groups page table entries of the same type into a single
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* description. It uses pg_state to track the range information while
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* iterating over the pte entries. When the continuity is broken it then
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* dumps out a description of the range.
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*/
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struct ptdump_pg_state {
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struct ptdump_state ptdump;
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struct ptdump_pg_level *pg_level;
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struct seq_file *seq;
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const struct addr_marker *marker;
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const struct mm_struct *mm;
52+
unsigned long start_address;
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int level;
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u64 current_prot;
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bool check_wx;
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unsigned long wx_pages;
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unsigned long uxn_pages;
58+
};
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void ptdump_walk(struct seq_file *s, struct ptdump_info *info);
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void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
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u64 val);
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#ifdef CONFIG_PTDUMP_DEBUGFS
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#define EFI_RUNTIME_MAP_END DEFAULT_MAP_WINDOW_64
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void __init ptdump_debugfs_register(struct ptdump_info *info, const char *name);
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#else
2967
static inline void ptdump_debugfs_register(struct ptdump_info *info,
3068
const char *name) { }
31-
#endif
69+
#endif /* CONFIG_PTDUMP_DEBUGFS */
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#else
71+
static inline void note_page(struct ptdump_state *pt_st, unsigned long addr,
72+
int level, u64 val) { }
3273
#endif /* CONFIG_PTDUMP_CORE */
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3475
#endif /* __ASM_PTDUMP_H */

‎arch/arm64/kvm/Kconfig

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Original file line numberDiff line numberDiff line change
@@ -66,4 +66,21 @@ config PROTECTED_NVHE_STACKTRACE
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If unsure, or not using protected nVHE (pKVM), say N.
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config PTDUMP_STAGE2_DEBUGFS
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bool "Present the stage-2 pagetables to debugfs"
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depends on KVM
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depends on DEBUG_KERNEL
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depends on DEBUG_FS
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depends on GENERIC_PTDUMP
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select PTDUMP_CORE
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default n
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help
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Say Y here if you want to show the stage-2 kernel pagetables
79+
layout in a debugfs file. This information is only useful for kernel developers
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who are working in architecture specific areas of the kernel.
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It is probably not a good idea to enable this feature in a production
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kernel.
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If in doubt, say N.
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endif # VIRTUALIZATION

‎arch/arm64/kvm/Makefile

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Original file line numberDiff line numberDiff line change
@@ -27,6 +27,7 @@ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \
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kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o pmu.o
2929
kvm-$(CONFIG_ARM64_PTR_AUTH) += pauth.o
30+
kvm-$(CONFIG_PTDUMP_STAGE2_DEBUGFS) += ptdump.o
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always-y := hyp_constants.h hyp-constants.s
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‎arch/arm64/kvm/arm.c

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -230,6 +230,7 @@ vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
230230
void kvm_arch_create_vm_debugfs(struct kvm *kvm)
231231
{
232232
kvm_sys_regs_create_debugfs(kvm);
233+
kvm_s2_ptdump_create_debugfs(kvm);
233234
}
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235236
static void kvm_destroy_mpidr_data(struct kvm *kvm)

‎arch/arm64/kvm/hyp/pgtable.c

Lines changed: 0 additions & 42 deletions
Original file line numberDiff line numberDiff line change
@@ -17,48 +17,6 @@
1717
#define KVM_PTE_TYPE_PAGE 1
1818
#define KVM_PTE_TYPE_TABLE 1
1919

20-
#define KVM_PTE_LEAF_ATTR_LO GENMASK(11, 2)
21-
22-
#define KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX GENMASK(4, 2)
23-
#define KVM_PTE_LEAF_ATTR_LO_S1_AP GENMASK(7, 6)
24-
#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RO \
25-
({ cpus_have_final_cap(ARM64_KVM_HVHE) ? 2 : 3; })
26-
#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RW \
27-
({ cpus_have_final_cap(ARM64_KVM_HVHE) ? 0 : 1; })
28-
#define KVM_PTE_LEAF_ATTR_LO_S1_SH GENMASK(9, 8)
29-
#define KVM_PTE_LEAF_ATTR_LO_S1_SH_IS 3
30-
#define KVM_PTE_LEAF_ATTR_LO_S1_AF BIT(10)
31-
32-
#define KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR GENMASK(5, 2)
33-
#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R BIT(6)
34-
#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W BIT(7)
35-
#define KVM_PTE_LEAF_ATTR_LO_S2_SH GENMASK(9, 8)
36-
#define KVM_PTE_LEAF_ATTR_LO_S2_SH_IS 3
37-
#define KVM_PTE_LEAF_ATTR_LO_S2_AF BIT(10)
38-
39-
#define KVM_PTE_LEAF_ATTR_HI GENMASK(63, 50)
40-
41-
#define KVM_PTE_LEAF_ATTR_HI_SW GENMASK(58, 55)
42-
43-
#define KVM_PTE_LEAF_ATTR_HI_S1_XN BIT(54)
44-
45-
#define KVM_PTE_LEAF_ATTR_HI_S2_XN BIT(54)
46-
47-
#define KVM_PTE_LEAF_ATTR_HI_S1_GP BIT(50)
48-
49-
#define KVM_PTE_LEAF_ATTR_S2_PERMS (KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R | \
50-
KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W | \
51-
KVM_PTE_LEAF_ATTR_HI_S2_XN)
52-
53-
#define KVM_INVALID_PTE_OWNER_MASK GENMASK(9, 2)
54-
#define KVM_MAX_OWNER_ID 1
55-
56-
/*
57-
* Used to indicate a pte for which a 'break-before-make' sequence is in
58-
* progress.
59-
*/
60-
#define KVM_INVALID_PTE_LOCKED BIT(10)
61-
6220
struct kvm_pgtable_walk_data {
6321
struct kvm_pgtable_walker *walker;
6422

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