Subject: [PATCH v3 05/13] modules, execmem: drop module_alloc

From: Mike Rapoport <[email-masked]>
Date: Mon, 18 Sep 2023 10:29:47 +0300

From: "Mike Rapoport (IBM)" <[email-masked]>

Define default parameters for address range for code allocations using
the current values in module_alloc() and make execmem_text_alloc() use
these defaults when an architecture does not supply its specific
parameters.

With this, execmem_text_alloc() implements memory allocation in a way
compatible with module_alloc() and can be used as a replacement for
module_alloc().

Signed-off-by: Mike Rapoport (IBM) <[email-masked]>
---
 include/linux/execmem.h      |  8 ++++++++
 include/linux/moduleloader.h | 12 ------------
 kernel/module/main.c         |  7 -------
 mm/execmem.c                 | 12 ++++++++----
 4 files changed, 16 insertions(+), 23 deletions(-)

diff --git a/include/linux/execmem.h b/include/linux/execmem.h
index 806ad1a0088d..519bdfdca595 100644
--- a/include/linux/execmem.h
+++ b/include/linux/execmem.h
@@ -4,6 +4,14 @@
 
 #include <linux/types.h>
 
+#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
+		!defined(CONFIG_KASAN_VMALLOC)
+#include <linux/kasan.h>
+#define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
+#else
+#define MODULE_ALIGN PAGE_SIZE
+#endif
+
 /**
  * enum execmem_type - types of executable memory ranges
  *
diff --git a/include/linux/moduleloader.h b/include/linux/moduleloader.h
index a23718aa2f4d..8c81f389117d 100644
--- a/include/linux/moduleloader.h
+++ b/include/linux/moduleloader.h
@@ -25,10 +25,6 @@ int module_frob_arch_sections(Elf_Ehdr *hdr,
 /* Additional bytes needed by arch in front of individual sections */
 unsigned int arch_mod_section_prepend(struct module *mod, unsigned int section);
 
-/* Allocator used for allocating struct module, core sections and init
-   sections.  Returns NULL on failure. */
-void *module_alloc(unsigned long size);
-
 /* Determines if the section name is an init section (that is only used during
  * module loading).
  */
@@ -118,12 +114,4 @@ void module_arch_cleanup(struct module *mod);
 /* Any cleanup before freeing mod->module_init */
 void module_arch_freeing_init(struct module *mod);
 
-#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
-		!defined(CONFIG_KASAN_VMALLOC)
-#include <linux/kasan.h>
-#define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
-#else
-#define MODULE_ALIGN PAGE_SIZE
-#endif
-
 #endif
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 4ec982cc943c..c4146bfcd0a7 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1601,13 +1601,6 @@ static void free_modinfo(struct module *mod)
 	}
 }
 
-void * __weak module_alloc(unsigned long size)
-{
-	return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
-			GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS,
-			NUMA_NO_NODE, __builtin_return_address(0));
-}
-
 bool __weak module_init_section(const char *name)
 {
 	return strstarts(name, ".init");
diff --git a/mm/execmem.c b/mm/execmem.c
index a8c2f44d0133..abcbd07e05ac 100644
--- a/mm/execmem.c
+++ b/mm/execmem.c
@@ -55,9 +55,6 @@ static void *execmem_alloc(size_t size, struct execmem_range *range)
 
 void *execmem_text_alloc(enum execmem_type type, size_t size)
 {
-	if (!execmem_params.ranges[type].start)
-		return module_alloc(size);
-
 	return execmem_alloc(size, &execmem_params.ranges[type]);
 }
 
@@ -111,8 +108,15 @@ void __init execmem_init(void)
 {
 	struct execmem_params *p = execmem_arch_params();
 
-	if (!p)
+	if (!p) {
+		p = &execmem_params;
+		p->ranges[EXECMEM_DEFAULT].start = VMALLOC_START;
+		p->ranges[EXECMEM_DEFAULT].end = VMALLOC_END;
+		p->ranges[EXECMEM_DEFAULT].pgprot = PAGE_KERNEL_EXEC;
+		p->ranges[EXECMEM_DEFAULT].alignment = 1;
+
 		return;
+	}
 
 	if (!execmem_validate_params(p))
 		return;
-- 
2.39.2