Merge branch 'for-next/stage1-lpa2' into for-next/core

* for-next/stage1-lpa2: (48 commits)
  : Add support for LPA2 and WXN and stage 1
  arm64/mm: Avoid ID mapping of kpti flag if it is no longer needed
  arm64/mm: Use generic __pud_free() helper in pud_free() implementation
  arm64: gitignore: ignore relacheck
  arm64: Use Signed/Unsigned enums for TGRAN{4,16,64} and VARange
  arm64: mm: Make PUD folding check in set_pud() a runtime check
  arm64: mm: add support for WXN memory translation attribute
  mm: add arch hook to validate mmap() prot flags
  arm64: defconfig: Enable LPA2 support
  arm64: Enable 52-bit virtual addressing for 4k and 16k granule configs
  arm64: kvm: avoid CONFIG_PGTABLE_LEVELS for runtime levels
  arm64: ptdump: Deal with translation levels folded at runtime
  arm64: ptdump: Disregard unaddressable VA space
  arm64: mm: Add support for folding PUDs at runtime
  arm64: kasan: Reduce minimum shadow alignment and enable 5 level paging
  arm64: mm: Add 5 level paging support to fixmap and swapper handling
  arm64: Enable LPA2 at boot if supported by the system
  arm64: mm: add LPA2 and 5 level paging support to G-to-nG conversion
  arm64: mm: Add definitions to support 5 levels of paging
  arm64: mm: Add LPA2 support to phys<->pte conversion routines
  arm64: mm: Wire up TCR.DS bit to PTE shareability fields
  ...

arch/arm64/Kconfig

@@ -165,7 +165,7 @@ config ARM64
 	select HAVE_ARCH_HUGE_VMAP
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE
-	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
+	select HAVE_ARCH_KASAN
 	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
 	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
 	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
@@ -370,7 +370,9 @@ config PGTABLE_LEVELS
 	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
 	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
 	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
+	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
 	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
+	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
 
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
@@ -398,13 +400,13 @@ config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
 config KASAN_SHADOW_OFFSET
 	hex
 	depends on KASAN_GENERIC || KASAN_SW_TAGS
-	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
-	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
+	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
+	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
 	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
 	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
 	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
-	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
-	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
+	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
+	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
 	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
 	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
 	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
@@ -1280,9 +1282,7 @@ endchoice
 
 choice
 	prompt "Virtual address space size"
-	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
-	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
-	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
+	default ARM64_VA_BITS_52
 	help
 	  Allows choosing one of multiple possible virtual address
 	  space sizes. The level of translation table is determined by
@@ -1309,7 +1309,7 @@ config ARM64_VA_BITS_48
 
 config ARM64_VA_BITS_52
 	bool "52-bit"
-	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
+	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
 	help
 	  Enable 52-bit virtual addressing for userspace when explicitly
 	  requested via a hint to mmap(). The kernel will also use 52-bit
@@ -1356,10 +1356,11 @@ choice
 
 config ARM64_PA_BITS_48
 	bool "48-bit"
+	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
 
 config ARM64_PA_BITS_52
-	bool "52-bit (ARMv8.2)"
-	depends on ARM64_64K_PAGES
+	bool "52-bit"
+	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
 	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
 	help
 	  Enable support for a 52-bit physical address space, introduced as
@@ -1376,6 +1377,10 @@ config ARM64_PA_BITS
 	default 48 if ARM64_PA_BITS_48
 	default 52 if ARM64_PA_BITS_52
 
+config ARM64_LPA2
+	def_bool y
+	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
+
 choice
 	prompt "Endianness"
 	default CPU_LITTLE_ENDIAN
@@ -1602,6 +1607,17 @@ config RODATA_FULL_DEFAULT_ENABLED
 	  This requires the linear region to be mapped down to pages,
 	  which may adversely affect performance in some cases.
 
+config ARM64_WXN
+	bool "Enable WXN attribute so all writable mappings are non-exec"
+	help
+	  Set the WXN bit in the SCTLR system register so that all writable
+	  mappings are treated as if the PXN/UXN bit is set as well.
+	  If this is set to Y, it can still be disabled at runtime by
+	  passing 'arm64.nowxn' on the kernel command line.
+
+	  This should only be set if no software needs to be supported that
+	  relies on being able to execute from writable mappings.
+
 config ARM64_SW_TTBR0_PAN
 	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
 	help

arch/arm64/configs/defconfig

@@ -76,7 +76,6 @@ CONFIG_ARCH_VEXPRESS=y
 CONFIG_ARCH_VISCONTI=y
 CONFIG_ARCH_XGENE=y
 CONFIG_ARCH_ZYNQMP=y
-CONFIG_ARM64_VA_BITS_48=y
 CONFIG_SCHED_MC=y
 CONFIG_SCHED_SMT=y
 CONFIG_NUMA=y

arch/arm64/include/asm/archrandom.h

@@ -129,6 +129,4 @@ static inline bool __init __early_cpu_has_rndr(void)
 	return (ftr >> ID_AA64ISAR0_EL1_RNDR_SHIFT) & 0xf;
 }
 
-u64 kaslr_early_init(void *fdt);
-
 #endif /* _ASM_ARCHRANDOM_H */

arch/arm64/include/asm/assembler.h

@@ -341,20 +341,6 @@ alternative_cb_end
 	bfi	\valreg, \t1sz, #TCR_T1SZ_OFFSET, #TCR_TxSZ_WIDTH
 	.endm
 
-/*
- * idmap_get_t0sz - get the T0SZ value needed to cover the ID map
- *
- * Calculate the maximum allowed value for TCR_EL1.T0SZ so that the
- * entire ID map region can be mapped. As T0SZ == (64 - #bits used),
- * this number conveniently equals the number of leading zeroes in
- * the physical address of _end.
- */
-	.macro	idmap_get_t0sz, reg
-	adrp	\reg, _end
-	orr	\reg, \reg, #(1 << VA_BITS_MIN) - 1
-	clz	\reg, \reg
-	.endm
-
 /*
  * tcr_compute_pa_size - set TCR.(I)PS to the highest supported
  * ID_AA64MMFR0_EL1.PARange value
@@ -586,18 +572,27 @@ alternative_endif
 	.endm
 
 /*
- * Offset ttbr1 to allow for 48-bit kernel VAs set with 52-bit PTRS_PER_PGD.
+ * If the kernel is built for 52-bit virtual addressing but the hardware only
+ * supports 48 bits, we cannot program the pgdir address into TTBR1 directly,
+ * but we have to add an offset so that the TTBR1 address corresponds with the
+ * pgdir entry that covers the lowest 48-bit addressable VA.
+ *
+ * Note that this trick is only used for LVA/64k pages - LPA2/4k pages uses an
+ * additional paging level, and on LPA2/16k pages, we would end up with a root
+ * level table with only 2 entries, which is suboptimal in terms of TLB
+ * utilization, so there we fall back to 47 bits of translation if LPA2 is not
+ * supported.
+ *
  * orr is used as it can cover the immediate value (and is idempotent).
- * In future this may be nop'ed out when dealing with 52-bit kernel VAs.
  * 	ttbr: Value of ttbr to set, modified.
  */
 	.macro	offset_ttbr1, ttbr, tmp
-#ifdef CONFIG_ARM64_VA_BITS_52
-	mrs_s	\tmp, SYS_ID_AA64MMFR2_EL1
-	and	\tmp, \tmp, #(0xf << ID_AA64MMFR2_EL1_VARange_SHIFT)
-	cbnz	\tmp, .Lskipoffs_\@
-	orr	\ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
-.Lskipoffs_\@ :
+#if defined(CONFIG_ARM64_VA_BITS_52) && !defined(CONFIG_ARM64_LPA2)
+	mrs	\tmp, tcr_el1
+	and	\tmp, \tmp, #TCR_T1SZ_MASK
+	cmp	\tmp, #TCR_T1SZ(VA_BITS_MIN)
+	orr	\tmp, \ttbr, #TTBR1_BADDR_4852_OFFSET
+	csel	\ttbr, \tmp, \ttbr, eq
 #endif
 	.endm
 
@@ -619,25 +614,13 @@ alternative_endif
 
 	.macro	phys_to_pte, pte, phys
 #ifdef CONFIG_ARM64_PA_BITS_52
-	/*
-	 * We assume \phys is 64K aligned and this is guaranteed by only
-	 * supporting this configuration with 64K pages.
-	 */
-	orr	\pte, \phys, \phys, lsr #36
-	and	\pte, \pte, #PTE_ADDR_MASK
+	orr	\pte, \phys, \phys, lsr #PTE_ADDR_HIGH_SHIFT
+	and	\pte, \pte, #PHYS_TO_PTE_ADDR_MASK
 #else
 	mov	\pte, \phys
 #endif
 	.endm
 
-	.macro	pte_to_phys, phys, pte
-	and	\phys, \pte, #PTE_ADDR_MASK
-#ifdef CONFIG_ARM64_PA_BITS_52
-	orr	\phys, \phys, \phys, lsl #PTE_ADDR_HIGH_SHIFT
-	and	\phys, \phys, GENMASK_ULL(PHYS_MASK_SHIFT - 1, PAGE_SHIFT)
-#endif
-	.endm
-
 /*
  * tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU.
  */

arch/arm64/include/asm/cpufeature.h

@@ -17,6 +17,8 @@
 
 #define ARM64_SW_FEATURE_OVERRIDE_NOKASLR	0
 #define ARM64_SW_FEATURE_OVERRIDE_HVHE		4
+#define ARM64_SW_FEATURE_OVERRIDE_RODATA_OFF	8
+#define ARM64_SW_FEATURE_OVERRIDE_NOWXN		12
 
 #ifndef __ASSEMBLY__
 
@@ -910,7 +912,9 @@ static inline unsigned int get_vmid_bits(u64 mmfr1)
 s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new, s64 cur);
 struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id);
 
+extern struct arm64_ftr_override id_aa64mmfr0_override;
 extern struct arm64_ftr_override id_aa64mmfr1_override;
+extern struct arm64_ftr_override id_aa64mmfr2_override;
 extern struct arm64_ftr_override id_aa64pfr0_override;
 extern struct arm64_ftr_override id_aa64pfr1_override;
 extern struct arm64_ftr_override id_aa64zfr0_override;
@@ -920,9 +924,121 @@ extern struct arm64_ftr_override id_aa64isar2_override;
 
 extern struct arm64_ftr_override arm64_sw_feature_override;
 
+static inline
+u64 arm64_apply_feature_override(u64 val, int feat, int width,
+				 const struct arm64_ftr_override *override)
+{
+	u64 oval = override->val;
+
+	/*
+	 * When it encounters an invalid override (e.g., an override that
+	 * cannot be honoured due to a missing CPU feature), the early idreg
+	 * override code will set the mask to 0x0 and the value to non-zero for
+	 * the field in question. In order to determine whether the override is
+	 * valid or not for the field we are interested in, we first need to
+	 * disregard bits belonging to other fields.
+	 */
+	oval &= GENMASK_ULL(feat + width - 1, feat);
+
+	/*
+	 * The override is valid if all value bits are accounted for in the
+	 * mask. If so, replace the masked bits with the override value.
+	 */
+	if (oval == (oval & override->mask)) {
+		val &= ~override->mask;
+		val |= oval;
+	}
+
+	/* Extract the field from the updated value */
+	return cpuid_feature_extract_unsigned_field(val, feat);
+}
+
+static inline bool arm64_test_sw_feature_override(int feat)
+{
+	/*
+	 * Software features are pseudo CPU features that have no underlying
+	 * CPUID system register value to apply the override to.
+	 */
+	return arm64_apply_feature_override(0, feat, 4,
+					    &arm64_sw_feature_override);
+}
+
+static inline bool kaslr_disabled_cmdline(void)
+{
+	return arm64_test_sw_feature_override(ARM64_SW_FEATURE_OVERRIDE_NOKASLR);
+}
+
+static inline bool arm64_wxn_enabled(void)
+{
+	if (!IS_ENABLED(CONFIG_ARM64_WXN))
+		return false;
+	return !arm64_test_sw_feature_override(ARM64_SW_FEATURE_OVERRIDE_NOWXN);
+}
+
 u32 get_kvm_ipa_limit(void);
 void dump_cpu_features(void);
 
+static inline bool cpu_has_bti(void)
+{
+	if (!IS_ENABLED(CONFIG_ARM64_BTI))
+		return false;
+
+	return arm64_apply_feature_override(read_cpuid(ID_AA64PFR1_EL1),
+					    ID_AA64PFR1_EL1_BT_SHIFT, 4,
+					    &id_aa64pfr1_override);
+}
+
+static inline bool cpu_has_pac(void)
+{
+	u64 isar1, isar2;
+
+	if (!IS_ENABLED(CONFIG_ARM64_PTR_AUTH))
+		return false;
+
+	isar1 = read_cpuid(ID_AA64ISAR1_EL1);
+	isar2 = read_cpuid(ID_AA64ISAR2_EL1);
+
+	if (arm64_apply_feature_override(isar1, ID_AA64ISAR1_EL1_APA_SHIFT, 4,
+					 &id_aa64isar1_override))
+		return true;
+
+	if (arm64_apply_feature_override(isar1, ID_AA64ISAR1_EL1_API_SHIFT, 4,
+					 &id_aa64isar1_override))
+		return true;
+
+	return arm64_apply_feature_override(isar2, ID_AA64ISAR2_EL1_APA3_SHIFT, 4,
+					    &id_aa64isar2_override);
+}
+
+static inline bool cpu_has_lva(void)
+{
+	u64 mmfr2;
+
+	mmfr2 = read_sysreg_s(SYS_ID_AA64MMFR2_EL1);
+	mmfr2 &= ~id_aa64mmfr2_override.mask;
+	mmfr2 |= id_aa64mmfr2_override.val;
+	return cpuid_feature_extract_unsigned_field(mmfr2,
+						    ID_AA64MMFR2_EL1_VARange_SHIFT);
+}
+
+static inline bool cpu_has_lpa2(void)
+{
+#ifdef CONFIG_ARM64_LPA2
+	u64 mmfr0;
+	int feat;
+
+	mmfr0 = read_sysreg(id_aa64mmfr0_el1);
+	mmfr0 &= ~id_aa64mmfr0_override.mask;
+	mmfr0 |= id_aa64mmfr0_override.val;
+	feat = cpuid_feature_extract_signed_field(mmfr0,
+						  ID_AA64MMFR0_EL1_TGRAN_SHIFT);
+
+	return feat >= ID_AA64MMFR0_EL1_TGRAN_LPA2;
+#else
+	return false;
+#endif
+}
+
 #endif /* __ASSEMBLY__ */
 
 #endif

arch/arm64/include/asm/esr.h

@@ -117,15 +117,9 @@
 #define ESR_ELx_FSC_ACCESS	(0x08)
 #define ESR_ELx_FSC_FAULT	(0x04)
 #define ESR_ELx_FSC_PERM	(0x0C)
-#define ESR_ELx_FSC_SEA_TTW0	(0x14)
-#define ESR_ELx_FSC_SEA_TTW1	(0x15)
-#define ESR_ELx_FSC_SEA_TTW2	(0x16)
-#define ESR_ELx_FSC_SEA_TTW3	(0x17)
+#define ESR_ELx_FSC_SEA_TTW(n)	(0x14 + (n))
 #define ESR_ELx_FSC_SECC	(0x18)
-#define ESR_ELx_FSC_SECC_TTW0	(0x1c)
-#define ESR_ELx_FSC_SECC_TTW1	(0x1d)
-#define ESR_ELx_FSC_SECC_TTW2	(0x1e)
-#define ESR_ELx_FSC_SECC_TTW3	(0x1f)
+#define ESR_ELx_FSC_SECC_TTW(n)	(0x1c + (n))
 
 /* ISS field definitions for Data Aborts */
 #define ESR_ELx_ISV_SHIFT	(24)
@@ -394,6 +388,9 @@ static inline bool esr_is_data_abort(unsigned long esr)
 
 static inline bool esr_fsc_is_translation_fault(unsigned long esr)
 {
+	/* Translation fault, level -1 */
+	if ((esr & ESR_ELx_FSC) == 0b101011)
+		return true;
 	return (esr & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_FAULT;
 }
 

arch/arm64/include/asm/fixmap.h

@@ -87,6 +87,7 @@ enum fixed_addresses {
 	FIX_PTE,
 	FIX_PMD,
 	FIX_PUD,
+	FIX_P4D,
 	FIX_PGD,
 
 	__end_of_fixed_addresses
@@ -100,7 +101,6 @@ enum fixed_addresses {
 #define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
 
 void __init early_fixmap_init(void);
-void __init fixmap_copy(pgd_t *pgdir);
 
 #define __early_set_fixmap __set_fixmap
 

arch/arm64/include/asm/kasan.h

@@ -17,11 +17,9 @@
 
 asmlinkage void kasan_early_init(void);
 void kasan_init(void);
-void kasan_copy_shadow(pgd_t *pgdir);
 
 #else
 static inline void kasan_init(void) { }
-static inline void kasan_copy_shadow(pgd_t *pgdir) { }
 #endif
 
 #endif