[PATCH v2 05/12] modules, execmem: drop module_alloc

From: Mike Rapoport
Date: Fri Jun 16 2023 - 04:52:34 EST


From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>

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 architecure 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) <rppt@xxxxxxxxxx>
---
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 68b2bfc79993..b9a97fcdf3c5 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
+
/**
* struct execmem_range - definition of a memory range suitable for code and
* related data allocations
diff --git a/include/linux/moduleloader.h b/include/linux/moduleloader.h
index b3374342f7af..4321682fe849 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).
*/
@@ -113,12 +109,4 @@ 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 43810a3bdb81..b445c5ad863a 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1600,13 +1600,6 @@ 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 2fe36dcc7bdf..a67acd75ffef 100644
--- a/mm/execmem.c
+++ b/mm/execmem.c
@@ -59,9 +59,6 @@ void *execmem_text_alloc(size_t size)
unsigned long fallback_end = execmem_params.modules.text.fallback_end;
bool kasan = execmem_params.modules.flags & EXECMEM_KASAN_SHADOW;

- if (!execmem_params.modules.text.start)
- return module_alloc(size);
-
return execmem_alloc(size, start, end, align, pgprot,
fallback_start, fallback_end, kasan);
}
@@ -108,8 +105,15 @@ void __init execmem_init(void)
{
struct execmem_params *p = execmem_arch_params();

- if (!p)
+ if (!p) {
+ p = &execmem_params;
+ p->modules.text.start = VMALLOC_START;
+ p->modules.text.end = VMALLOC_END;
+ p->modules.text.pgprot = PAGE_KERNEL_EXEC;
+ p->modules.text.alignment = 1;
+
return;
+ }

if (!execmem_validate_params(p))
return;
--
2.35.1