Merge branch 'x86/mm'

Depends on the simplifications from commit 1d7e707af446 ("Revert "x86/module: prepare module loading for ROX allocations of text"")

Signed-off-by: Peter Zijlstra <[e-mail]>

arch/um/kernel/um_arch.c

···
 	os_check_bugs();
 }
 
-void apply_seal_endbr(s32 *start, s32 *end, struct module *mod)
+void apply_seal_endbr(s32 *start, s32 *end)
 {
 }
 
-void apply_retpolines(s32 *start, s32 *end, struct module *mod)
+void apply_retpolines(s32 *start, s32 *end)
 {
 }
 
-void apply_returns(s32 *start, s32 *end, struct module *mod)
+void apply_returns(s32 *start, s32 *end)
 {
 }
 
 void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
-		   s32 *start_cfi, s32 *end_cfi, struct module *mod)
+		   s32 *start_cfi, s32 *end_cfi)
 {
 }
 
-void apply_alternatives(struct alt_instr *start, struct alt_instr *end,
-			struct module *mod)
+void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 {
 }
 

arch/x86/Kconfig

···
 	select ARCH_HAS_DMA_OPS			if GART_IOMMU || XEN
 	select ARCH_HAS_EARLY_DEBUG		if KGDB
 	select ARCH_HAS_ELF_RANDOMIZE
+	select ARCH_HAS_EXECMEM_ROX		if X86_64
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL

arch/x86/entry/vdso/vma.c

···
 
 	apply_alternatives((struct alt_instr *)(image->data + image->alt),
 			   (struct alt_instr *)(image->data + image->alt +
-						image->alt_len),
-			   NULL);
+						image->alt_len));
 
 	return 0;
 }

arch/x86/include/asm/alternative.h

···
  * instructions were patched in already:
  */
 extern int alternatives_patched;
-struct module;
 
 extern void alternative_instructions(void);
-extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end,
-			       struct module *mod);
-extern void apply_retpolines(s32 *start, s32 *end, struct module *mod);
-extern void apply_returns(s32 *start, s32 *end, struct module *mod);
-extern void apply_seal_endbr(s32 *start, s32 *end, struct module *mod);
+extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
+extern void apply_retpolines(s32 *start, s32 *end);
+extern void apply_returns(s32 *start, s32 *end);
+extern void apply_seal_endbr(s32 *start, s32 *end);
 extern void apply_fineibt(s32 *start_retpoline, s32 *end_retpoine,
-			  s32 *start_cfi, s32 *end_cfi, struct module *mod);
+			  s32 *start_cfi, s32 *end_cfi);
+
+struct module;
 
 struct callthunk_sites {
 	s32				*call_start, *call_end;

arch/x86/include/asm/pgtable_types.h

···
 #define _PAGE_BIT_CPA_TEST	_PAGE_BIT_SOFTW1
 #define _PAGE_BIT_UFFD_WP	_PAGE_BIT_SOFTW2 /* userfaultfd wrprotected */
 #define _PAGE_BIT_SOFT_DIRTY	_PAGE_BIT_SOFTW3 /* software dirty tracking */
+#define _PAGE_BIT_KERNEL_4K	_PAGE_BIT_SOFTW3 /* page must not be converted to large */
 #define _PAGE_BIT_DEVMAP	_PAGE_BIT_SOFTW4
 
 #ifdef CONFIG_X86_64
···
 #define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
 #define _PAGE_SPECIAL	(_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL)
 #define _PAGE_CPA_TEST	(_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST)
+#define _PAGE_KERNEL_4K	(_AT(pteval_t, 1) << _PAGE_BIT_KERNEL_4K)
 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
 #define _PAGE_PKEY_BIT0	(_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT0)
 #define _PAGE_PKEY_BIT1	(_AT(pteval_t, 1) << _PAGE_BIT_PKEY_BIT1)

arch/x86/include/asm/tlbflush.h

···
 	flush_tlb_mm_range((vma)->vm_mm, start, end,			\
 			   ((vma)->vm_flags & VM_HUGETLB)		\
 				? huge_page_shift(hstate_vma(vma))	\
-				: PAGE_SHIFT, false)
+				: PAGE_SHIFT, true)
 
 extern void flush_tlb_all(void);
 extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,

arch/x86/kernel/alternative.c

···
  * Rewrite the "call BUG_func" replacement to point to the target of the
  * indirect pv_ops call "call *disp(%ip)".
  */
-static int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a,
-			    struct module *mod)
+static int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a)
 {
-	u8 *wr_instr = module_writable_address(mod, instr);
 	void *target, *bug = &BUG_func;
 	s32 disp;
 
···
 	}
 
 	if (a->instrlen != 6 ||
-	    wr_instr[0] != CALL_RIP_REL_OPCODE ||
-	    wr_instr[1] != CALL_RIP_REL_MODRM) {
+	    instr[0] != CALL_RIP_REL_OPCODE ||
+	    instr[1] != CALL_RIP_REL_MODRM) {
 		pr_err("ALT_FLAG_DIRECT_CALL set for unrecognized indirect call\n");
 		BUG();
 	}
 
 	/* Skip CALL_RIP_REL_OPCODE and CALL_RIP_REL_MODRM */
-	disp = *(s32 *)(wr_instr + 2);
+	disp = *(s32 *)(instr + 2);
 #ifdef CONFIG_X86_64
 	/* ff 15 00 00 00 00   call   *0x0(%rip) */
 	/* target address is stored at "next instruction + disp". */
···
  * to refetch changed I$ lines.
  */
 void __init_or_module noinline apply_alternatives(struct alt_instr *start,
-						  struct alt_instr *end,
-						  struct module *mod)
+						  struct alt_instr *end)
 {
 	u8 insn_buff[MAX_PATCH_LEN];
 	u8 *instr, *replacement;
···
 	 */
 	for (a = start; a < end; a++) {
 		int insn_buff_sz = 0;
-		u8 *wr_instr, *wr_replacement;
 
 		/*
 		 * In case of nested ALTERNATIVE()s the outer alternative might
···
 		}
 
 		instr = instr_va(a);
-		wr_instr = module_writable_address(mod, instr);
-
 		replacement = (u8 *)&a->repl_offset + a->repl_offset;
-		wr_replacement = module_writable_address(mod, replacement);
-
 		BUG_ON(a->instrlen > sizeof(insn_buff));
 		BUG_ON(a->cpuid >= (NCAPINTS + NBUGINTS) * 32);
 
···
 		 *   patch if feature is *NOT* present.
 		 */
 		if (!boot_cpu_has(a->cpuid) == !(a->flags & ALT_FLAG_NOT)) {
-			memcpy(insn_buff, wr_instr, a->instrlen);
+			memcpy(insn_buff, instr, a->instrlen);
 			optimize_nops(instr, insn_buff, a->instrlen);
-			text_poke_early(wr_instr, insn_buff, a->instrlen);
+			text_poke_early(instr, insn_buff, a->instrlen);
 			continue;
 		}
 
···
 			instr, instr, a->instrlen,
 			replacement, a->replacementlen, a->flags);
 
-		memcpy(insn_buff, wr_replacement, a->replacementlen);
+		memcpy(insn_buff, replacement, a->replacementlen);
 		insn_buff_sz = a->replacementlen;
 
 		if (a->flags & ALT_FLAG_DIRECT_CALL) {
-			insn_buff_sz = alt_replace_call(instr, insn_buff, a,
-							mod);
+			insn_buff_sz = alt_replace_call(instr, insn_buff, a);
 			if (insn_buff_sz < 0)
 				continue;
 		}
···
 
 		apply_relocation(insn_buff, instr, a->instrlen, replacement, a->replacementlen);
 
-		DUMP_BYTES(ALT, wr_instr, a->instrlen, "%px:   old_insn: ", instr);
+		DUMP_BYTES(ALT, instr, a->instrlen, "%px:   old_insn: ", instr);
 		DUMP_BYTES(ALT, replacement, a->replacementlen, "%px:   rpl_insn: ", replacement);
 		DUMP_BYTES(ALT, insn_buff, insn_buff_sz, "%px: final_insn: ", instr);
 
-		text_poke_early(wr_instr, insn_buff, insn_buff_sz);
+		text_poke_early(instr, insn_buff, insn_buff_sz);
 	}
 
 	kasan_enable_current();
···
 /*
  * Generated by 'objtool --retpoline'.
  */
-void __init_or_module noinline apply_retpolines(s32 *start, s32 *end,
-						struct module *mod)
+void __init_or_module noinline apply_retpolines(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 		struct insn insn;
 		int len, ret;
 		u8 bytes[16];
 		u8 op1, op2;
 
-		ret = insn_decode_kernel(&insn, wr_addr);
+		ret = insn_decode_kernel(&insn, addr);
 		if (WARN_ON_ONCE(ret < 0))
 			continue;
 
···
 		len = patch_retpoline(addr, &insn, bytes);
 		if (len == insn.length) {
 			optimize_nops(addr, bytes, len);
-			DUMP_BYTES(RETPOLINE, ((u8*)wr_addr),  len, "%px: orig: ", addr);
+			DUMP_BYTES(RETPOLINE, ((u8*)addr),  len, "%px: orig: ", addr);
 			DUMP_BYTES(RETPOLINE, ((u8*)bytes), len, "%px: repl: ", addr);
-			text_poke_early(wr_addr, bytes, len);
+			text_poke_early(addr, bytes, len);
 		}
 	}
 }
···
 	return i;
 }
 
-void __init_or_module noinline apply_returns(s32 *start, s32 *end,
-					     struct module *mod)
+void __init_or_module noinline apply_returns(s32 *start, s32 *end)
 {
 	s32 *s;
 
···
 
 	for (s = start; s < end; s++) {
 		void *dest = NULL, *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 		struct insn insn;
 		int len, ret;
 		u8 bytes[16];
 		u8 op;
 
-		ret = insn_decode_kernel(&insn, wr_addr);
+		ret = insn_decode_kernel(&insn, addr);
 		if (WARN_ON_ONCE(ret < 0))
 			continue;
 
···
 
 		len = patch_return(addr, &insn, bytes);
 		if (len == insn.length) {
-			DUMP_BYTES(RET, ((u8*)wr_addr),  len, "%px: orig: ", addr);
+			DUMP_BYTES(RET, ((u8*)addr),  len, "%px: orig: ", addr);
 			DUMP_BYTES(RET, ((u8*)bytes), len, "%px: repl: ", addr);
-			text_poke_early(wr_addr, bytes, len);
+			text_poke_early(addr, bytes, len);
 		}
 	}
 }
 #else
-void __init_or_module noinline apply_returns(s32 *start, s32 *end,
-					     struct module *mod) { }
+void __init_or_module noinline apply_returns(s32 *start, s32 *end) { }
 #endif /* CONFIG_MITIGATION_RETHUNK */
 
 #else /* !CONFIG_MITIGATION_RETPOLINE || !CONFIG_OBJTOOL */
 
-void __init_or_module noinline apply_retpolines(s32 *start, s32 *end,
-						struct module *mod) { }
-void __init_or_module noinline apply_returns(s32 *start, s32 *end,
-					     struct module *mod) { }
+void __init_or_module noinline apply_retpolines(s32 *start, s32 *end) { }
+void __init_or_module noinline apply_returns(s32 *start, s32 *end) { }
 
 #endif /* CONFIG_MITIGATION_RETPOLINE && CONFIG_OBJTOOL */
 
 #ifdef CONFIG_X86_KERNEL_IBT
 
-static void poison_cfi(void *addr, void *wr_addr);
+static void poison_cfi(void *addr);
 
-static void __init_or_module poison_endbr(void *addr, void *wr_addr, bool warn)
+static void __init_or_module poison_endbr(void *addr, bool warn)
 {
 	u32 endbr, poison = gen_endbr_poison();
 
-	if (WARN_ON_ONCE(get_kernel_nofault(endbr, wr_addr)))
+	if (WARN_ON_ONCE(get_kernel_nofault(endbr, addr)))
 		return;
 
 	if (!is_endbr(endbr)) {
···
 	 */
 	DUMP_BYTES(ENDBR, ((u8*)addr), 4, "%px: orig: ", addr);
 	DUMP_BYTES(ENDBR, ((u8*)&poison), 4, "%px: repl: ", addr);
-	text_poke_early(wr_addr, &poison, 4);
+	text_poke_early(addr, &poison, 4);
 }
 
 /*
···
  * Seal the functions for indirect calls by clobbering the ENDBR instructions
  * and the kCFI hash value.
  */
-void __init_or_module noinline apply_seal_endbr(s32 *start, s32 *end, struct module *mod)
+void __init_or_module noinline apply_seal_endbr(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 
-		poison_endbr(addr, wr_addr, true);
+		poison_endbr(addr, true);
 		if (IS_ENABLED(CONFIG_FINEIBT))
-			poison_cfi(addr - 16, wr_addr - 16);
+			poison_cfi(addr - 16);
 	}
 }
 
 #else
 
-void __init_or_module apply_seal_endbr(s32 *start, s32 *end, struct module *mod) { }
+void __init_or_module apply_seal_endbr(s32 *start, s32 *end) { }
 
 #endif /* CONFIG_X86_KERNEL_IBT */
 
···
 }
 
 /* .retpoline_sites */
-static int cfi_disable_callers(s32 *start, s32 *end, struct module *mod)
+static int cfi_disable_callers(s32 *start, s32 *end)
 {
 	/*
 	 * Disable kCFI by patching in a JMP.d8, this leaves the hash immediate
···
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr;
 		u32 hash;
 
 		addr -= fineibt_caller_size;
-		wr_addr = module_writable_address(mod, addr);
-		hash = decode_caller_hash(wr_addr);
-
+		hash = decode_caller_hash(addr);
 		if (!hash) /* nocfi callers */
 			continue;
 
-		text_poke_early(wr_addr, jmp, 2);
+		text_poke_early(addr, jmp, 2);
 	}
 
 	return 0;
 }
 
-static int cfi_enable_callers(s32 *start, s32 *end, struct module *mod)
+static int cfi_enable_callers(s32 *start, s32 *end)
 {
 	/*
 	 * Re-enable kCFI, undo what cfi_disable_callers() did.
···
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr;
 		u32 hash;
 
 		addr -= fineibt_caller_size;
-		wr_addr = module_writable_address(mod, addr);
-		hash = decode_caller_hash(wr_addr);
+		hash = decode_caller_hash(addr);
 		if (!hash) /* nocfi callers */
 			continue;
 
-		text_poke_early(wr_addr, mov, 2);
+		text_poke_early(addr, mov, 2);
 	}
 
 	return 0;
 }
 
 /* .cfi_sites */
-static int cfi_rand_preamble(s32 *start, s32 *end, struct module *mod)
+static int cfi_rand_preamble(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 		u32 hash;
 
-		hash = decode_preamble_hash(wr_addr);
+		hash = decode_preamble_hash(addr);
 		if (WARN(!hash, "no CFI hash found at: %pS %px %*ph\n",
 			 addr, addr, 5, addr))
 			return -EINVAL;
 
 		hash = cfi_rehash(hash);
-		text_poke_early(wr_addr + 1, &hash, 4);
+		text_poke_early(addr + 1, &hash, 4);
 	}
 
 	return 0;
 }
 
-static int cfi_rewrite_preamble(s32 *start, s32 *end, struct module *mod)
+static int cfi_rewrite_preamble(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 		u32 hash;
 
-		hash = decode_preamble_hash(wr_addr);
+		hash = decode_preamble_hash(addr);
 		if (WARN(!hash, "no CFI hash found at: %pS %px %*ph\n",
 			 addr, addr, 5, addr))
 			return -EINVAL;
 
-		text_poke_early(wr_addr, fineibt_preamble_start, fineibt_preamble_size);
-		WARN_ON(*(u32 *)(wr_addr + fineibt_preamble_hash) != 0x12345678);
-		text_poke_early(wr_addr + fineibt_preamble_hash, &hash, 4);
+		text_poke_early(addr, fineibt_preamble_start, fineibt_preamble_size);
+		WARN_ON(*(u32 *)(addr + fineibt_preamble_hash) != 0x12345678);
+		text_poke_early(addr + fineibt_preamble_hash, &hash, 4);
 	}
 
 	return 0;
 }
 
-static void cfi_rewrite_endbr(s32 *start, s32 *end, struct module *mod)
+static void cfi_rewrite_endbr(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr = module_writable_address(mod, addr);
 
-		poison_endbr(addr + 16, wr_addr + 16, false);
+		poison_endbr(addr+16, false);
 	}
 }
 
 /* .retpoline_sites */
-static int cfi_rand_callers(s32 *start, s32 *end, struct module *mod)
+static int cfi_rand_callers(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr;
 		u32 hash;
 
 		addr -= fineibt_caller_size;
-		wr_addr = module_writable_address(mod, addr);
-		hash = decode_caller_hash(wr_addr);
+		hash = decode_caller_hash(addr);
 		if (hash) {
 			hash = -cfi_rehash(hash);
-			text_poke_early(wr_addr + 2, &hash, 4);
+			text_poke_early(addr + 2, &hash, 4);
 		}
 	}
 
 	return 0;
 }
 
-static int cfi_rewrite_callers(s32 *start, s32 *end, struct module *mod)
+static int cfi_rewrite_callers(s32 *start, s32 *end)
 {
 	s32 *s;
 
 	for (s = start; s < end; s++) {
 		void *addr = (void *)s + *s;
-		void *wr_addr;
 		u32 hash;
 
 		addr -= fineibt_caller_size;
-		wr_addr = module_writable_address(mod, addr);
-		hash = decode_caller_hash(wr_addr);
+		hash = decode_caller_hash(addr);
 		if (hash) {
-			text_poke_early(wr_addr, fineibt_caller_start, fineibt_caller_size);
-			WARN_ON(*(u32 *)(wr_addr + fineibt_caller_hash) != 0x12345678);
-			text_poke_early(wr_addr + fineibt_caller_hash, &hash, 4);
+			text_poke_early(addr, fineibt_caller_start, fineibt_caller_size);
+			WARN_ON(*(u32 *)(addr + fineibt_caller_hash) != 0x12345678);
+			text_poke_early(addr + fineibt_caller_hash, &hash, 4);
 		}
 		/* rely on apply_retpolines() */
 	}
···
 }
 
 static void __apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
-			    s32 *start_cfi, s32 *end_cfi, struct module *mod)
+			    s32 *start_cfi, s32 *end_cfi, bool builtin)
 {
-	bool builtin = mod ? false : true;
 	int ret;
 
 	if (WARN_ONCE(fineibt_preamble_size != 16,
···
 	 * rewrite them. This disables all CFI. If this succeeds but any of the
 	 * later stages fails, we're without CFI.
 	 */
-	ret = cfi_disable_callers(start_retpoline, end_retpoline, mod);
+	ret = cfi_disable_callers(start_retpoline, end_retpoline);
 	if (ret)
 		goto err;
 
···
 			cfi_bpf_subprog_hash = cfi_rehash(cfi_bpf_subprog_hash);
 		}
 
-		ret = cfi_rand_preamble(start_cfi, end_cfi, mod);
+		ret = cfi_rand_preamble(start_cfi, end_cfi);
 		if (ret)
 			goto err;
 
-		ret = cfi_rand_callers(start_retpoline, end_retpoline, mod);
+		ret = cfi_rand_callers(start_retpoline, end_retpoline);
 		if (ret)
 			goto err;
 	}
···
 		return;
 
 	case CFI_KCFI:
-		ret = cfi_enable_callers(start_retpoline, end_retpoline, mod);
+		ret = cfi_enable_callers(start_retpoline, end_retpoline);
 		if (ret)
 			goto err;
 
···
 
 	case CFI_FINEIBT:
 		/* place the FineIBT preamble at func()-16 */
-		ret = cfi_rewrite_preamble(start_cfi, end_cfi, mod);
+		ret = cfi_rewrite_preamble(start_cfi, end_cfi);
 		if (ret)
 			goto err;
 
 		/* rewrite the callers to target func()-16 */
-		ret = cfi_rewrite_callers(start_retpoline, end_retpoline, mod);
+		ret = cfi_rewrite_callers(start_retpoline, end_retpoline);
 		if (ret)
 			goto err;
 
 		/* now that nobody targets func()+0, remove ENDBR there */
-		cfi_rewrite_endbr(start_cfi, end_cfi, mod);
+		cfi_rewrite_endbr(start_cfi, end_cfi);
 
 		if (builtin)
 			pr_info("Using FineIBT CFI\n");
···
 	*(u32 *)addr = 0;
 }
 
-static void poison_cfi(void *addr, void *wr_addr)
+static void poison_cfi(void *addr)
 {
 	switch (cfi_mode) {
 	case CFI_FINEIBT:
···
 		 *	ud2
 		 * 1:	nop
 		 */
-		poison_endbr(addr, wr_addr, false);
-		poison_hash(wr_addr + fineibt_preamble_hash);
+		poison_endbr(addr, false);
+		poison_hash(addr + fineibt_preamble_hash);
 		break;
 
 	case CFI_KCFI:
···
 		 *	movl	$0, %eax
 		 *	.skip	11, 0x90
 		 */
-		poison_hash(wr_addr + 1);
+		poison_hash(addr + 1);
 		break;
 
 	default:
···
 #else
 
 static void __apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
-			    s32 *start_cfi, s32 *end_cfi, struct module *mod)
+			    s32 *start_cfi, s32 *end_cfi, bool builtin)
 {
 }
 
 #ifdef CONFIG_X86_KERNEL_IBT
-static void poison_cfi(void *addr, void *wr_addr) { }
+static void poison_cfi(void *addr) { }
 #endif
 
 #endif
 
 void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
-		   s32 *start_cfi, s32 *end_cfi, struct module *mod)
+		   s32 *start_cfi, s32 *end_cfi)
 {
 	return __apply_fineibt(start_retpoline, end_retpoline,
-			       start_cfi, end_cfi, mod);
+			       start_cfi, end_cfi,
+			       /* .builtin = */ false);
 }
 
 #ifdef CONFIG_SMP
···
 	paravirt_set_cap();
 
 	__apply_fineibt(__retpoline_sites, __retpoline_sites_end,
-			__cfi_sites, __cfi_sites_end, NULL);
+			__cfi_sites, __cfi_sites_end, true);
 
 	/*
 	 * Rewrite the retpolines, must be done before alternatives since
 	 * those can rewrite the retpoline thunks.
 	 */
-	apply_retpolines(__retpoline_sites, __retpoline_sites_end, NULL);
-	apply_returns(__return_sites, __return_sites_end, NULL);
+	apply_retpolines(__retpoline_sites, __retpoline_sites_end);
+	apply_returns(__return_sites, __return_sites_end);
 
-	apply_alternatives(__alt_instructions, __alt_instructions_end, NULL);
+	apply_alternatives(__alt_instructions, __alt_instructions_end);
 
 	/*
 	 * Now all calls are established. Apply the call thunks if
···
 	/*
 	 * Seal all functions that do not have their address taken.
 	 */
-	apply_seal_endbr(__ibt_endbr_seal, __ibt_endbr_seal_end, NULL);
+	apply_seal_endbr(__ibt_endbr_seal, __ibt_endbr_seal_end);
 
 #ifdef CONFIG_SMP
 	/* Patch to UP if other cpus not imminent. */

arch/x86/kernel/ftrace.c

···
 		return ret;
 
 	/* replace the text with the new text */
-	if (ftrace_poke_late) {
+	if (ftrace_poke_late)
 		text_poke_queue((void *)ip, new_code, MCOUNT_INSN_SIZE, NULL);
-	} else {
-		mutex_lock(&text_mutex);
-		text_poke((void *)ip, new_code, MCOUNT_INSN_SIZE);
-		mutex_unlock(&text_mutex);
-	}
+	else
+		text_poke_early((void *)ip, new_code, MCOUNT_INSN_SIZE);
 	return 0;
 }
 
···
 	unsigned const char op_ref[] = { 0x48, 0x8b, 0x15 };
 	unsigned const char retq[] = { RET_INSN_OPCODE, INT3_INSN_OPCODE };
 	union ftrace_op_code_union op_ptr;
-	void *ret;
+	int ret;
 
 	if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
 		start_offset = (unsigned long)ftrace_regs_caller;
···
 	npages = DIV_ROUND_UP(*tramp_size, PAGE_SIZE);
 
 	/* Copy ftrace_caller onto the trampoline memory */
-	ret = text_poke_copy(trampoline, (void *)start_offset, size);
-	if (WARN_ON(!ret))
+	ret = copy_from_kernel_nofault(trampoline, (void *)start_offset, size);
+	if (WARN_ON(ret < 0))
 		goto fail;
 
 	ip = trampoline + size;
 	if (cpu_feature_enabled(X86_FEATURE_RETHUNK))
 		__text_gen_insn(ip, JMP32_INSN_OPCODE, ip, x86_return_thunk, JMP32_INSN_SIZE);
 	else
-		text_poke_copy(ip, retq, sizeof(retq));
+		memcpy(ip, retq, sizeof(retq));
 
 	/* No need to test direct calls on created trampolines */
 	if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
···
 		ip = trampoline + (jmp_offset - start_offset);
 		if (WARN_ON(*(char *)ip != 0x75))
 			goto fail;
-		if (!text_poke_copy(ip, x86_nops[2], 2))
+		ret = copy_from_kernel_nofault(ip, x86_nops[2], 2);
+		if (ret < 0)
 			goto fail;
 	}
 
···
 	 */
 
 	ptr = (unsigned long *)(trampoline + size + RET_SIZE);
-	text_poke_copy(ptr, &ops, sizeof(unsigned long));
+	*ptr = (unsigned long)ops;
 
 	op_offset -= start_offset;
 	memcpy(&op_ptr, trampoline + op_offset, OP_REF_SIZE);
···
 	op_ptr.offset = offset;
 
 	/* put in the new offset to the ftrace_ops */
-	text_poke_copy(trampoline + op_offset, &op_ptr, OP_REF_SIZE);
+	memcpy(trampoline + op_offset, &op_ptr, OP_REF_SIZE);
 
 	/* put in the call to the function */
 	mutex_lock(&text_mutex);
···
 	 * the depth accounting before the call already.
 	 */
 	dest = ftrace_ops_get_func(ops);
-	text_poke_copy_locked(trampoline + call_offset,
-	      text_gen_insn(CALL_INSN_OPCODE, trampoline + call_offset, dest),
-	      CALL_INSN_SIZE, false);
+	memcpy(trampoline + call_offset,
+	       text_gen_insn(CALL_INSN_OPCODE, trampoline + call_offset, dest),
+	       CALL_INSN_SIZE);
 	mutex_unlock(&text_mutex);
 
 	/* ALLOC_TRAMP flags lets us know we created it */

arch/x86/kernel/module.c

···
 		}
 
 		if (apply) {
-			void *wr_loc = module_writable_address(me, loc);
-
-			if (memcmp(wr_loc, &zero, size)) {
+			if (memcmp(loc, &zero, size)) {
 				pr_err("x86/modules: Invalid relocation target, existing value is nonzero for type %d, loc %p, val %Lx\n",
 				       (int)ELF64_R_TYPE(rel[i].r_info), loc, val);
 				return -ENOEXEC;
 			}
-			write(wr_loc, &val, size);
+			write(loc, &val, size);
 		} else {
 			if (memcmp(loc, &val, size)) {
 				pr_warn("x86/modules: Invalid relocation target, existing value does not match expected value for type %d, loc %p, val %Lx\n",
 					(int)ELF64_R_TYPE(rel[i].r_info), loc, val);
 				return -ENOEXEC;
 			}
-			/* FIXME: needs care for ROX module allocations */
 			write(loc, &zero, size);
 		}
 	}
···
 		    const Elf_Shdr *sechdrs,
 		    struct module *me)
 {
-	const Elf_Shdr *s, *alt = NULL,
+	const Elf_Shdr *s, *alt = NULL, *locks = NULL,
 		*orc = NULL, *orc_ip = NULL,
 		*retpolines = NULL, *returns = NULL, *ibt_endbr = NULL,
 		*calls = NULL, *cfi = NULL;
···
 	for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
 		if (!strcmp(".altinstructions", secstrings + s->sh_name))
 			alt = s;
+		if (!strcmp(".smp_locks", secstrings + s->sh_name))
+			locks = s;
 		if (!strcmp(".orc_unwind", secstrings + s->sh_name))
 			orc = s;
 		if (!strcmp(".orc_unwind_ip", secstrings + s->sh_name))
···
 			csize = cfi->sh_size;
 		}
 
-		apply_fineibt(rseg, rseg + rsize, cseg, cseg + csize, me);
+		apply_fineibt(rseg, rseg + rsize, cseg, cseg + csize);
 	}
 	if (retpolines) {
 		void *rseg = (void *)retpolines->sh_addr;
-		apply_retpolines(rseg, rseg + retpolines->sh_size, me);
+		apply_retpolines(rseg, rseg + retpolines->sh_size);
 	}
 	if (returns) {
 		void *rseg = (void *)returns->sh_addr;
-		apply_returns(rseg, rseg + returns->sh_size, me);
+		apply_returns(rseg, rseg + returns->sh_size);
 	}
 	if (alt) {
 		/* patch .altinstructions */
 		void *aseg = (void *)alt->sh_addr;
-		apply_alternatives(aseg, aseg + alt->sh_size, me);
+		apply_alternatives(aseg, aseg + alt->sh_size);
 	}
 	if (calls || alt) {
 		struct callthunk_sites cs = {};
···
 	}
 	if (ibt_endbr) {
 		void *iseg = (void *)ibt_endbr->sh_addr;
-		apply_seal_endbr(iseg, iseg + ibt_endbr->sh_size, me);
+		apply_seal_endbr(iseg, iseg + ibt_endbr->sh_size);
 	}
-
-	if (orc && orc_ip)
-		unwind_module_init(me, (void *)orc_ip->sh_addr, orc_ip->sh_size,
-				   (void *)orc->sh_addr, orc->sh_size);
-
-	return 0;
-}
-
-int module_post_finalize(const Elf_Ehdr *hdr,
-			 const Elf_Shdr *sechdrs,
-			 struct module *me)
-{
-	const Elf_Shdr *s, *locks = NULL;
-	char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
-
-	for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
-		if (!strcmp(".smp_locks", secstrings + s->sh_name))
-			locks = s;
-	}
-
 	if (locks) {
 		void *lseg = (void *)locks->sh_addr;
 		void *text = me->mem[MOD_TEXT].base;
···
 					    lseg, lseg + locks->sh_size,
 					    text, text_end);
 	}
+
+	if (orc && orc_ip)
+		unwind_module_init(me, (void *)orc_ip->sh_addr, orc_ip->sh_size,
+				   (void *)orc->sh_addr, orc->sh_size);
 
 	return 0;
 }

arch/x86/mm/pat/cpa-test.c

···
 			break;
 
 		case 1:
-			err = change_page_attr_set(addrs, len[1], PAGE_CPA_TEST, 1);
+			err = change_page_attr_set(addrs, len[i], PAGE_CPA_TEST, 1);
 			break;
 
 		case 2:

arch/x86/mm/pat/set_memory.c

···
 #define CPA_ARRAY 2
 #define CPA_PAGES_ARRAY 4
 #define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
+#define CPA_COLLAPSE 16 /* try to collapse large pages */
 
 static inline pgprot_t cachemode2pgprot(enum page_cache_mode pcm)
 {
···
 	direct_pages_count[level - 1] += PTRS_PER_PTE;
 }
 
+static void collapse_page_count(int level)
+{
+	direct_pages_count[level]++;
+	if (system_state == SYSTEM_RUNNING) {
+		if (level == PG_LEVEL_2M)
+			count_vm_event(DIRECT_MAP_LEVEL2_COLLAPSE);
+		else if (level == PG_LEVEL_1G)
+			count_vm_event(DIRECT_MAP_LEVEL3_COLLAPSE);
+	}
+	direct_pages_count[level - 1] -= PTRS_PER_PTE;
+}
+
 void arch_report_meminfo(struct seq_file *m)
 {
 	seq_printf(m, "DirectMap4k:    %8lu kB\n",
···
 }
 #else
 static inline void split_page_count(int level) { }
+static inline void collapse_page_count(int level) { }
 #endif
 
 #ifdef CONFIG_X86_CPA_STATISTICS
···
 		flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
 }
 
-static void cpa_flush(struct cpa_data *data, int cache)
+static int collapse_large_pages(unsigned long addr, struct list_head *pgtables);
+
+static void cpa_collapse_large_pages(struct cpa_data *cpa)
 {
-	struct cpa_data *cpa = data;
+	unsigned long start, addr, end;
+	struct ptdesc *ptdesc, *tmp;
+	LIST_HEAD(pgtables);
+	int collapsed = 0;
+	int i;
+
+	if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) {
+		for (i = 0; i < cpa->numpages; i++)
+			collapsed += collapse_large_pages(__cpa_addr(cpa, i),
+							  &pgtables);
+	} else {
+		addr = __cpa_addr(cpa, 0);
+		start = addr & PMD_MASK;
+		end = addr + PAGE_SIZE * cpa->numpages;
+
+		for (addr = start; within(addr, start, end); addr += PMD_SIZE)
+			collapsed += collapse_large_pages(addr, &pgtables);
+	}
+
+	if (!collapsed)
+		return;
+
+	flush_tlb_all();
+
+	list_for_each_entry_safe(ptdesc, tmp, &pgtables, pt_list) {
+		list_del(&ptdesc->pt_list);
+		__free_page(ptdesc_page(ptdesc));
+	}
+}
+
+static void cpa_flush(struct cpa_data *cpa, int cache)
+{
 	unsigned int i;
 
 	BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
 
 	if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
 		cpa_flush_all(cache);
-		return;
+		goto collapse_large_pages;
 	}
 
 	if (cpa->force_flush_all || cpa->numpages > tlb_single_page_flush_ceiling)
···
 		on_each_cpu(__cpa_flush_tlb, cpa, 1);
 
 	if (!cache)
-		return;
+		goto collapse_large_pages;
 
 	mb();
 	for (i = 0; i < cpa->numpages; i++) {
···
 			clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
 	}
 	mb();
+
+collapse_large_pages:
+	if (cpa->flags & CPA_COLLAPSE)
+		cpa_collapse_large_pages(cpa);
 }
 
 static bool overlaps(unsigned long r1_start, unsigned long r1_end,
···
 		__free_page(base);
 
 	return 0;
+}
+
+static int collapse_pmd_page(pmd_t *pmd, unsigned long addr,
+			     struct list_head *pgtables)
+{
+	pmd_t _pmd, old_pmd;
+	pte_t *pte, first;
+	unsigned long pfn;
+	pgprot_t pgprot;
+	int i = 0;
+
+	addr &= PMD_MASK;
+	pte = pte_offset_kernel(pmd, addr);
+	first = *pte;
+	pfn = pte_pfn(first);
+
+	/* Make sure alignment is suitable */
+	if (PFN_PHYS(pfn) & ~PMD_MASK)
+		return 0;
+
+	/* The page is 4k intentionally */
+	if (pte_flags(first) & _PAGE_KERNEL_4K)
+		return 0;
+
+	/* Check that the rest of PTEs are compatible with the first one */
+	for (i = 1, pte++; i < PTRS_PER_PTE; i++, pte++) {
+		pte_t entry = *pte;
+
+		if (!pte_present(entry))
+			return 0;
+		if (pte_flags(entry) != pte_flags(first))
+			return 0;
+		if (pte_pfn(entry) != pte_pfn(first) + i)
+			return 0;
+	}
+
+	old_pmd = *pmd;
+
+	/* Success: set up a large page */
+	pgprot = pgprot_4k_2_large(pte_pgprot(first));
+	pgprot_val(pgprot) |= _PAGE_PSE;
+	_pmd = pfn_pmd(pfn, pgprot);
+	set_pmd(pmd, _pmd);
+
+	/* Queue the page table to be freed after TLB flush */
+	list_add(&page_ptdesc(pmd_page(old_pmd))->pt_list, pgtables);
+
+	if (IS_ENABLED(CONFIG_X86_32) && !SHARED_KERNEL_PMD) {
+		struct page *page;
+
+		/* Update all PGD tables to use the same large page */
+		list_for_each_entry(page, &pgd_list, lru) {
+			pgd_t *pgd = (pgd_t *)page_address(page) + pgd_index(addr);
+			p4d_t *p4d = p4d_offset(pgd, addr);
+			pud_t *pud = pud_offset(p4d, addr);
+			pmd_t *pmd = pmd_offset(pud, addr);
+			/* Something is wrong if entries doesn't match */
+			if (WARN_ON(pmd_val(old_pmd) != pmd_val(*pmd)))
+				continue;
+			set_pmd(pmd, _pmd);
+		}
+	}
+
+	if (virt_addr_valid(addr) && pfn_range_is_mapped(pfn, pfn + 1))
+		collapse_page_count(PG_LEVEL_2M);
+
+	return 1;
+}
+
+static int collapse_pud_page(pud_t *pud, unsigned long addr,
+			     struct list_head *pgtables)
+{
+	unsigned long pfn;
+	pmd_t *pmd, first;
+	int i;
+
+	if (!direct_gbpages)
+		return 0;
+
+	addr &= PUD_MASK;
+	pmd = pmd_offset(pud, addr);
+	first = *pmd;
+
+	/*
+	 * To restore PUD page all PMD entries must be large and
+	 * have suitable alignment
+	 */
+	pfn = pmd_pfn(first);
+	if (!pmd_leaf(first) || (PFN_PHYS(pfn) & ~PUD_MASK))
+		return 0;
+
+	/*
+	 * To restore PUD page, all following PMDs must be compatible with the
+	 * first one.
+	 */
+	for (i = 1, pmd++; i < PTRS_PER_PMD; i++, pmd++) {
+		pmd_t entry = *pmd;
+
+		if (!pmd_present(entry) || !pmd_leaf(entry))
+			return 0;
+		if (pmd_flags(entry) != pmd_flags(first))
+			return 0;
+		if (pmd_pfn(entry) != pmd_pfn(first) + i * PTRS_PER_PTE)
+			return 0;
+	}
+
+	/* Restore PUD page and queue page table to be freed after TLB flush */
+	list_add(&page_ptdesc(pud_page(*pud))->pt_list, pgtables);
+	set_pud(pud, pfn_pud(pfn, pmd_pgprot(first)));
+
+	if (virt_addr_valid(addr) && pfn_range_is_mapped(pfn, pfn + 1))
+		collapse_page_count(PG_LEVEL_1G);
+
+	return 1;
+}
+
+/*
+ * Collapse PMD and PUD pages in the kernel mapping around the address where
+ * possible.
+ *
+ * Caller must flush TLB and free page tables queued on the list before
+ * touching the new entries. CPU must not see TLB entries of different size
+ * with different attributes.
+ */
+static int collapse_large_pages(unsigned long addr, struct list_head *pgtables)
+{
+	int collapsed = 0;
+	pgd_t *pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	addr &= PMD_MASK;
+
+	spin_lock(&pgd_lock);
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		goto out;
+	p4d = p4d_offset(pgd, addr);
+	if (p4d_none(*p4d))
+		goto out;
+	pud = pud_offset(p4d, addr);
+	if (!pud_present(*pud) || pud_leaf(*pud))
+		goto out;
+	pmd = pmd_offset(pud, addr);
+	if (!pmd_present(*pmd) || pmd_leaf(*pmd))
+		goto out;
+
+	collapsed = collapse_pmd_page(pmd, addr, pgtables);
+	if (collapsed)
+		collapsed += collapse_pud_page(pud, addr, pgtables);
+
+out:
+	spin_unlock(&pgd_lock);
+	return collapsed;
 }
 
 static bool try_to_free_pte_page(pte_t *pte)
···
 	if (__supported_pte_mask & _PAGE_NX)
 		clr.pgprot |= _PAGE_NX;
 
-	return change_page_attr_clear(&addr, numpages, clr, 0);
+	return change_page_attr_set_clr(&addr, numpages, __pgprot(0), clr, 0,
+					CPA_COLLAPSE, NULL);
 }
 
 int set_memory_rw(unsigned long addr, int numpages)
···
 
 int set_memory_4k(unsigned long addr, int numpages)
 {
-	return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
+	return change_page_attr_set_clr(&addr, numpages,
+					__pgprot(_PAGE_KERNEL_4K),
 					__pgprot(0), 1, 0, NULL);
 }
 

arch/x86/mm/tlb.c

···
 	if (loaded_mm != current_mm)
 		return false;
 
-	VM_WARN_ON_ONCE(current_mm->pgd != __va(read_cr3_pa()));
+	VM_WARN_ON_ONCE(__pa(current_mm->pgd) != read_cr3_pa());
 
 	return true;
 }

include/linux/execmem.h

···
  * Architectures that use EXECMEM_ROX_CACHE must implement this.
  */
 void execmem_fill_trapping_insns(void *ptr, size_t size, bool writable);
+
+/**
+ * execmem_make_temp_rw - temporarily remap region with read-write
+ *			  permissions
+ * @ptr:	address of the region to remap
+ * @size:	size of the region to remap
+ *
+ * Remaps a part of the cached large page in the ROX cache in the range
+ * [@ptr, @ptr + @size) as writable and not executable. The caller must
+ * have exclusive ownership of this range and ensure nothing will try to
+ * execute code in this range.
+ *
+ * Return: 0 on success or negative error code on failure.
+ */
+int execmem_make_temp_rw(void *ptr, size_t size);
+
+/**
+ * execmem_restore_rox - restore read-only-execute permissions
+ * @ptr:	address of the region to remap
+ * @size:	size of the region to remap
+ *
+ * Restores read-only-execute permissions on a range [@ptr, @ptr + @size)
+ * after it was temporarily remapped as writable. Relies on architecture
+ * implementation of set_memory_rox() to restore mapping using large pages.
+ *
+ * Return: 0 on success or negative error code on failure.
+ */
+int execmem_restore_rox(void *ptr, size_t size);
+#else
+static inline int execmem_make_temp_rw(void *ptr, size_t size) { return 0; }
+static inline int execmem_restore_rox(void *ptr, size_t size) { return 0; }
 #endif
 
 /**

include/linux/module.h

···
 
 struct module_memory {
 	void *base;
-	void *rw_copy;
 	bool is_rox;
 	unsigned int size;
 
···
 
 void set_module_sig_enforced(void);
 
-void *__module_writable_address(struct module *mod, void *loc);
-
-static inline void *module_writable_address(struct module *mod, void *loc)
-{
-	if (!IS_ENABLED(CONFIG_ARCH_HAS_EXECMEM_ROX) || !mod ||
-	    mod->state != MODULE_STATE_UNFORMED)
-		return loc;
-	return __module_writable_address(mod, loc);
-}
-
 #else /* !CONFIG_MODULES... */
 
 static inline struct module *__module_address(unsigned long addr)
···
 static inline bool module_is_coming(struct module *mod)
 {
 	return false;
-}
-
-static inline void *module_writable_address(struct module *mod, void *loc)
-{
-	return loc;
 }
 #endif /* CONFIG_MODULES */
 

include/linux/moduleloader.h

···
 		    const Elf_Shdr *sechdrs,
 		    struct module *mod);
 
-int module_post_finalize(const Elf_Ehdr *hdr,
-			 const Elf_Shdr *sechdrs,
-			 struct module *mod);
-
 #ifdef CONFIG_MODULES
 void flush_module_init_free_work(void);
 #else

include/linux/vm_event_item.h

···
 #ifdef CONFIG_X86
 		DIRECT_MAP_LEVEL2_SPLIT,
 		DIRECT_MAP_LEVEL3_SPLIT,
+		DIRECT_MAP_LEVEL2_COLLAPSE,
+		DIRECT_MAP_LEVEL3_COLLAPSE,
 #endif
 #ifdef CONFIG_PER_VMA_LOCK_STATS
 		VMA_LOCK_SUCCESS,

kernel/module/main.c

···
 {
 }
 
-void *__module_writable_address(struct module *mod, void *loc)
-{
-	for_class_mod_mem_type(type, text) {
-		struct module_memory *mem = &mod->mem[type];
-
-		if (loc >= mem->base && loc < mem->base + mem->size)
-			return loc + (mem->rw_copy - mem->base);
-	}
-
-	return loc;
-}
-
 static int module_memory_alloc(struct module *mod, enum mod_mem_type type)
 {
 	unsigned int size = PAGE_ALIGN(mod->mem[type].size);
···
 	if (!ptr)
 		return -ENOMEM;
 
-	mod->mem[type].base = ptr;
-
 	if (execmem_is_rox(execmem_type)) {
-		ptr = vzalloc(size);
+		int err = execmem_make_temp_rw(ptr, size);
 
-		if (!ptr) {
-			execmem_free(mod->mem[type].base);
+		if (err) {
+			execmem_free(ptr);
 			return -ENOMEM;
 		}
 
-		mod->mem[type].rw_copy = ptr;
 		mod->mem[type].is_rox = true;
-	} else {
-		mod->mem[type].rw_copy = mod->mem[type].base;
-		memset(mod->mem[type].base, 0, size);
 	}
 
 	/*
···
 	 * *do* eventually get freed, but let's just keep things simple
 	 * and avoid *any* false positives.
 	 */
-	kmemleak_not_leak(ptr);
+	if (!mod->mem[type].is_rox)
+		kmemleak_not_leak(ptr);
+
+	memset(ptr, 0, size);
+	mod->mem[type].base = ptr;
 
 	return 0;
+}
+
+static void module_memory_restore_rox(struct module *mod)
+{
+	for_class_mod_mem_type(type, text) {
+		struct module_memory *mem = &mod->mem[type];
+
+		if (mem->is_rox)
+			execmem_restore_rox(mem->base, mem->size);
+	}
 }
 
 static void module_memory_free(struct module *mod, enum mod_mem_type type)
 {
 	struct module_memory *mem = &mod->mem[type];
-
-	if (mem->is_rox)
-		vfree(mem->rw_copy);
 
 	execmem_free(mem->base);
 }
···
 	for_each_mod_mem_type(type) {
 		if (!mod->mem[type].size) {
 			mod->mem[type].base = NULL;
-			mod->mem[type].rw_copy = NULL;
 			continue;
 		}
 
···
 		void *dest;
 		Elf_Shdr *shdr = &info->sechdrs[i];
 		const char *sname;
-		unsigned long addr;
 
 		if (!(shdr->sh_flags & SHF_ALLOC))
 			continue;
···
 				ret = PTR_ERR(dest);
 				goto out_err;
 			}
-			addr = (unsigned long)dest;
 			codetag_section_found = true;
 		} else {
 			enum mod_mem_type type = shdr->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
 			unsigned long offset = shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK;
 
-			addr = (unsigned long)mod->mem[type].base + offset;
-			dest = mod->mem[type].rw_copy + offset;
+			dest = mod->mem[type].base + offset;
 		}
 
 		if (shdr->sh_type != SHT_NOBITS) {
···
 		 * users of info can keep taking advantage and using the newly
 		 * minted official memory area.
 		 */
-		shdr->sh_addr = addr;
+		shdr->sh_addr = (unsigned long)dest;
 		pr_debug("\t0x%lx 0x%.8lx %s\n", (long)shdr->sh_addr,
 			 (long)shdr->sh_size, info->secstrings + shdr->sh_name);
 	}
 
 	return 0;
 out_err:
+	module_memory_restore_rox(mod);
 	for (t--; t >= 0; t--)
 		module_memory_free(mod, t);
 	if (codetag_section_found)
···
 	return 0;
 }
 
-int __weak module_post_finalize(const Elf_Ehdr *hdr,
-				const Elf_Shdr *sechdrs,
-				struct module *me)
-{
-	return 0;
-}
-
 static int post_relocation(struct module *mod, const struct load_info *info)
 {
-	int ret;
-
 	/* Sort exception table now relocations are done. */
 	sort_extable(mod->extable, mod->extable + mod->num_exentries);
 
···
 	add_kallsyms(mod, info);
 
 	/* Arch-specific module finalizing. */
-	ret = module_finalize(info->hdr, info->sechdrs, mod);
-	if (ret)
-		return ret;
-
-	for_each_mod_mem_type(type) {
-		struct module_memory *mem = &mod->mem[type];
-
-		if (mem->is_rox) {
-			if (!execmem_update_copy(mem->base, mem->rw_copy,
-						 mem->size))
-				return -ENOMEM;
-
-			vfree(mem->rw_copy);
-			mem->rw_copy = NULL;
-		}
-	}
-
-	return module_post_finalize(info->hdr, info->sechdrs, mod);
+	return module_finalize(info->hdr, info->sechdrs, mod);
 }
 
 /* Call module constructors. */
···
 				       mod->mem[type].size);
 	}
 
+	module_memory_restore_rox(mod);
 	module_deallocate(mod, info);
  free_copy:
 	/*

kernel/module/strict_rwx.c

···
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <linux/set_memory.h>
+#include <linux/execmem.h>
 #include "internal.h"
 
 static int module_set_memory(const struct module *mod, enum mod_mem_type type,
···
 int module_enable_text_rox(const struct module *mod)
 {
 	for_class_mod_mem_type(type, text) {
+		const struct module_memory *mem = &mod->mem[type];
 		int ret;
 
-		if (mod->mem[type].is_rox)
-			continue;
-
-		if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
+		if (mem->is_rox)
+			ret = execmem_restore_rox(mem->base, mem->size);
+		else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
 			ret = module_set_memory(mod, type, set_memory_rox);
 		else
 			ret = module_set_memory(mod, type, set_memory_x);

mm/execmem.c

···
 static int execmem_cache_populate(struct execmem_range *range, size_t size)
 {
 	unsigned long vm_flags = VM_ALLOW_HUGE_VMAP;
-	unsigned long start, end;
 	struct vm_struct *vm;
 	size_t alloc_size;
 	int err = -ENOMEM;
···
 	/* fill memory with instructions that will trap */
 	execmem_fill_trapping_insns(p, alloc_size, /* writable = */ true);
 
-	start = (unsigned long)p;
-	end = start + alloc_size;
-
-	vunmap_range(start, end);
-
-	err = execmem_set_direct_map_valid(vm, false);
-	if (err)
-		goto err_free_mem;
-
-	err = vmap_pages_range_noflush(start, end, range->pgprot, vm->pages,
-				       PMD_SHIFT);
+	err = set_memory_rox((unsigned long)p, vm->nr_pages);
 	if (err)
 		goto err_free_mem;
 
 	err = execmem_cache_add(p, alloc_size);
 	if (err)
-		goto err_free_mem;
+		goto err_reset_direct_map;
 
 	return 0;
 
+err_reset_direct_map:
+	execmem_set_direct_map_valid(vm, true);
 err_free_mem:
 	vfree(p);
 	return err;
···
 
 	return true;
 }
+
+int execmem_make_temp_rw(void *ptr, size_t size)
+{
+	unsigned int nr = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	unsigned long addr = (unsigned long)ptr;
+	int ret;
+
+	ret = set_memory_nx(addr, nr);
+	if (ret)
+		return ret;
+
+	return set_memory_rw(addr, nr);
+}
+
+int execmem_restore_rox(void *ptr, size_t size)
+{
+	unsigned int nr = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	unsigned long addr = (unsigned long)ptr;
+
+	return set_memory_rox(addr, nr);
+}
+
 #else /* CONFIG_ARCH_HAS_EXECMEM_ROX */
 static void *execmem_cache_alloc(struct execmem_range *range, size_t size)
 {

mm/vmstat.c

···
 #ifdef CONFIG_X86
 	"direct_map_level2_splits",
 	"direct_map_level3_splits",
+	"direct_map_level2_collapses",
+	"direct_map_level3_collapses",
 #endif
 #ifdef CONFIG_PER_VMA_LOCK_STATS
 	"vma_lock_success",