[PATCH v2 0/4] Miscellaneous cleanups

[PATCH v2 0/4] Miscellaneous cleanups

[Christophe Leroy]

This series applies on top of my series "Allocate module text and data separately" v5.

It does some cleanup around the settling of modules's layout page flags:
- Make module_enable_x() independent of CONFIG_ARCH_HAS_STRICT_MODULE_RWX
- Reunify everything into strict_rwx.c
- Change big hammer BUG_ON()s into WARN_ON()s
- Change misleading debug_align() to strict_align()

Changes in v2:
- Rebased on top of my series "Allocate module text and data separately" v5
- Moved the Kconfig patch out of this series, it is an independent change

Christophe Leroy (4):
  module: Make module_enable_x() independent of
    CONFIG_ARCH_HAS_STRICT_MODULE_RWX
  module: Move module_enable_x() and frob_text() in strict_rwx.c
  module: Rework layout alignment to avoid BUG_ON()s
  module: Rename debug_align() as strict_align()

 kernel/module/Makefile     |  3 +-
 kernel/module/internal.h   | 26 +++----------
 kernel/module/kallsyms.c   |  4 +-
 kernel/module/main.c       | 58 ++++++-----------------------
 kernel/module/strict_rwx.c | 76 +++++++++++++++++++++++++++++++++-----
 5 files changed, 88 insertions(+), 79 deletions(-)

-- 
2.34.1

[PATCH v2 1/4] module: Make module_enable_x() independent of CONFIG_ARCH_HAS_STRICT_MODULE_RWX

[Christophe Leroy]

module_enable_x() has nothing to do with CONFIG_ARCH_HAS_STRICT_MODULE_RWX
allthough by coincidence architectures who need module_enable_x() are
selection CONFIG_ARCH_HAS_STRICT_MODULE_RWX.

Enable module_enable_x() for everyone everytime. If an architecture
already has module text set executable, it's a no-op.

Don't check text_size alignment. When CONFIG_STRICT_MODULE_RWX is set
the verification is already done in frob_rodata(). When
CONFIG_STRICT_MODULE_RWX is not set it is not a big deal to have the
start of data as executable. Just make sure we entirely get the last
page when the boundary is not aligned.

And don't BUG on misaligned base as some architectures like nios2
use kmalloc() for allocating modules. So just bail out in that case.
If that's a problem, a page fault will occur later anyway.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 kernel/module/internal.h |  6 ++----
 kernel/module/main.c     | 12 +++++-------
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 6911c7533ede..7178b7c09cdd 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -27,9 +27,9 @@
 /*
  * Modules' sections will be aligned on page boundaries
  * to ensure complete separation of code and data, but
- * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
+ * only when CONFIG_STRICT_MODULE_RWX=y
  */
-#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
+#ifdef CONFIG_STRICT_MODULE_RWX
 # define debug_align(X) PAGE_ALIGN(X)
 #else
 # define debug_align(X) (X)
@@ -182,10 +182,8 @@ static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *
 }
 #endif /* CONFIG_MODULES_TREE_LOOKUP */
 
-#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
 void frob_text(const struct module_layout *layout, int (*set_memory)(unsigned long start,
 								     int num_pages));
-#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
 
 #ifdef CONFIG_STRICT_MODULE_RWX
 void module_enable_ro(const struct module *mod, bool after_init);
diff --git a/kernel/module/main.c b/kernel/module/main.c
index db503a212532..be3b31ba6e16 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1162,24 +1162,22 @@ resolve_symbol_wait(struct module *mod,
  * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
  * whether we are strict.
  */
-#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
 void frob_text(const struct module_layout *layout,
 	       int (*set_memory)(unsigned long start, int num_pages))
 {
-	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
 	set_memory((unsigned long)layout->base,
-		   layout->text_size >> PAGE_SHIFT);
+		   PAGE_ALIGN(layout->text_size) >> PAGE_SHIFT);
 }
 
 static void module_enable_x(const struct module *mod)
 {
+	if (!PAGE_ALIGNED(mod->core_layout.base) ||
+	    !PAGE_ALIGNED(mod->init_layout.base))
+		return;
+
 	frob_text(&mod->core_layout, set_memory_x);
 	frob_text(&mod->init_layout, set_memory_x);
 }
-#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
-static void module_enable_x(const struct module *mod) { }
-#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
 
 void __weak module_memfree(void *module_region)
 {
-- 
2.34.1

[PATCH v2 2/4] module: Move module_enable_x() and frob_text() in strict_rwx.c

[Christophe Leroy]

Move module_enable_x() together with module_enable_nx() and
module_enable_ro().

Those three functions are going together, they are all used
to set up the correct page flags on the different sections.

As module_enable_x() is used independently of
CONFIG_STRICT_MODULE_RWX, build strict_rwx.c all the time and
use IS_ENABLED(CONFIG_STRICT_MODULE_RWX) when relevant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 kernel/module/Makefile     |  3 +--
 kernel/module/internal.h   | 15 +-----------
 kernel/module/main.c       | 37 -----------------------------
 kernel/module/strict_rwx.c | 48 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 50 insertions(+), 53 deletions(-)

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index a46e6361017f..a94f7b8b2740 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -7,12 +7,11 @@
 # and produce insane amounts of uninteresting coverage.
 KCOV_INSTRUMENT_module.o := n
 
-obj-y += main.o
+obj-y += main.o strict_rwx.o
 obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o
 obj-$(CONFIG_MODULE_SIG) += signing.o
 obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
-obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
 obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
 obj-$(CONFIG_KALLSYMS) += kallsyms.o
 obj-$(CONFIG_PROC_FS) += procfs.o
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 7178b7c09cdd..276e3f49a4ae 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -182,25 +182,12 @@ static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *
 }
 #endif /* CONFIG_MODULES_TREE_LOOKUP */
 
-void frob_text(const struct module_layout *layout, int (*set_memory)(unsigned long start,
-								     int num_pages));
-
-#ifdef CONFIG_STRICT_MODULE_RWX
 void module_enable_ro(const struct module *mod, bool after_init);
 void module_enable_nx(const struct module *mod);
+void module_enable_x(const struct module *mod);
 int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
 				char *secstrings, struct module *mod);
 
-#else /* !CONFIG_STRICT_MODULE_RWX */
-static inline void module_enable_nx(const struct module *mod) { }
-static inline void module_enable_ro(const struct module *mod, bool after_init) {}
-static inline int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
-				       char *secstrings, struct module *mod)
-{
-	return 0;
-}
-#endif /* CONFIG_STRICT_MODULE_RWX */
-
 #ifdef CONFIG_MODULE_SIG
 int module_sig_check(struct load_info *info, int flags);
 #else /* !CONFIG_MODULE_SIG */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index be3b31ba6e16..47addf849ef7 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1142,43 +1142,6 @@ resolve_symbol_wait(struct module *mod,
 	return ksym;
 }
 
-/*
- * LKM RO/NX protection: protect module's text/ro-data
- * from modification and any data from execution.
- *
- * General layout of module is:
- *          [text] [read-only-data] [ro-after-init] [writable data]
- * text_size -----^                ^               ^               ^
- * ro_size ------------------------|               |               |
- * ro_after_init_size -----------------------------|               |
- * size -----------------------------------------------------------|
- *
- * These values are always page-aligned (as is base)
- */
-
-/*
- * Since some arches are moving towards PAGE_KERNEL module allocations instead
- * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the
- * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
- * whether we are strict.
- */
-void frob_text(const struct module_layout *layout,
-	       int (*set_memory)(unsigned long start, int num_pages))
-{
-	set_memory((unsigned long)layout->base,
-		   PAGE_ALIGN(layout->text_size) >> PAGE_SHIFT);
-}
-
-static void module_enable_x(const struct module *mod)
-{
-	if (!PAGE_ALIGNED(mod->core_layout.base) ||
-	    !PAGE_ALIGNED(mod->init_layout.base))
-		return;
-
-	frob_text(&mod->core_layout, set_memory_x);
-	frob_text(&mod->init_layout, set_memory_x);
-}
-
 void __weak module_memfree(void *module_region)
 {
 	/*
diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c
index 1a6b9573260b..6b99be9e88e1 100644
--- a/kernel/module/strict_rwx.c
+++ b/kernel/module/strict_rwx.c
@@ -11,6 +11,34 @@
 #include <linux/set_memory.h>
 #include "internal.h"
 
+/*
+ * LKM RO/NX protection: protect module's text/ro-data
+ * from modification and any data from execution.
+ *
+ * General layout of module is:
+ *          [text] [read-only-data] [ro-after-init] [writable data]
+ * text_size -----^                ^               ^               ^
+ * ro_size ------------------------|               |               |
+ * ro_after_init_size -----------------------------|               |
+ * size -----------------------------------------------------------|
+ *
+ * These values are always page-aligned (as is base) when
+ * CONFIG_STRICT_MODULE_RWX is set.
+ */
+
+/*
+ * Since some arches are moving towards PAGE_KERNEL module allocations instead
+ * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() independent of
+ * CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we
+ * are strict.
+ */
+static void frob_text(const struct module_layout *layout,
+		      int (*set_memory)(unsigned long start, int num_pages))
+{
+	set_memory((unsigned long)layout->base,
+		   PAGE_ALIGN(layout->text_size) >> PAGE_SHIFT);
+}
+
 static void frob_rodata(const struct module_layout *layout,
 		 int (*set_memory)(unsigned long start, int num_pages))
 {
@@ -41,10 +69,24 @@ static void frob_writable_data(const struct module_layout *layout,
 		   (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
 }
 
+void module_enable_x(const struct module *mod)
+{
+	if (!PAGE_ALIGNED(mod->core_layout.base) ||
+	    !PAGE_ALIGNED(mod->init_layout.base))
+		return;
+
+	frob_text(&mod->core_layout, set_memory_x);
+	frob_text(&mod->init_layout, set_memory_x);
+}
+
 void module_enable_ro(const struct module *mod, bool after_init)
 {
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
+		return;
+#ifdef CONFIG_STRICT_MODULE_RWX
 	if (!rodata_enabled)
 		return;
+#endif
 
 	set_vm_flush_reset_perms(mod->core_layout.base);
 	set_vm_flush_reset_perms(mod->init_layout.base);
@@ -60,6 +102,9 @@ void module_enable_ro(const struct module *mod, bool after_init)
 
 void module_enable_nx(const struct module *mod)
 {
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
+		return;
+
 	frob_rodata(&mod->data_layout, set_memory_nx);
 	frob_ro_after_init(&mod->data_layout, set_memory_nx);
 	frob_writable_data(&mod->data_layout, set_memory_nx);
@@ -73,6 +118,9 @@ int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
 	const unsigned long shf_wx = SHF_WRITE | SHF_EXECINSTR;
 	int i;
 
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
+		return 0;
+
 	for (i = 0; i < hdr->e_shnum; i++) {
 		if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) {
 			pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n",
-- 
2.34.1

[PATCH v2 3/4] module: Rework layout alignment to avoid BUG_ON()s

[Christophe Leroy]

Perform layout alignment verification up front and WARN_ON()
and fail module loading instead of crashing the machine.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 kernel/module/internal.h   |  1 +
 kernel/module/main.c       |  5 +++++
 kernel/module/strict_rwx.c | 28 +++++++++++++++++++---------
 3 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 276e3f49a4ae..f3dcd40f300c 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -187,6 +187,7 @@ void module_enable_nx(const struct module *mod);
 void module_enable_x(const struct module *mod);
 int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
 				char *secstrings, struct module *mod);
+bool module_check_misalignment(const struct module *mod);
 
 #ifdef CONFIG_MODULE_SIG
 int module_sig_check(struct load_info *info, int flags);
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 47addf849ef7..4876e2beb5b6 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2596,6 +2596,9 @@ static int complete_formation(struct module *mod, struct load_info *info)
 	/* This relies on module_mutex for list integrity. */
 	module_bug_finalize(info->hdr, info->sechdrs, mod);
 
+	if (module_check_misalignment(mod))
+		goto out_misaligned;
+
 	module_enable_ro(mod, false);
 	module_enable_nx(mod);
 	module_enable_x(mod);
@@ -2609,6 +2612,8 @@ static int complete_formation(struct module *mod, struct load_info *info)
 
 	return 0;
 
+out_misaligned:
+	err = -EINVAL;
 out:
 	mutex_unlock(&module_mutex);
 	return err;
diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c
index 6b99be9e88e1..14fbea66f12f 100644
--- a/kernel/module/strict_rwx.c
+++ b/kernel/module/strict_rwx.c
@@ -42,9 +42,6 @@ static void frob_text(const struct module_layout *layout,
 static void frob_rodata(const struct module_layout *layout,
 		 int (*set_memory)(unsigned long start, int num_pages))
 {
-	BUG_ON(!PAGE_ALIGNED(layout->base));
-	BUG_ON(!PAGE_ALIGNED(layout->text_size));
-	BUG_ON(!PAGE_ALIGNED(layout->ro_size));
 	set_memory((unsigned long)layout->base + layout->text_size,
 		   (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
 }
@@ -52,9 +49,6 @@ static void frob_rodata(const struct module_layout *layout,
 static void frob_ro_after_init(const struct module_layout *layout,
 			int (*set_memory)(unsigned long start, int num_pages))
 {
-	BUG_ON(!PAGE_ALIGNED(layout->base));
-	BUG_ON(!PAGE_ALIGNED(layout->ro_size));
-	BUG_ON(!PAGE_ALIGNED(layout->ro_after_init_size));
 	set_memory((unsigned long)layout->base + layout->ro_size,
 		   (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
 }
@@ -62,13 +56,29 @@ static void frob_ro_after_init(const struct module_layout *layout,
 static void frob_writable_data(const struct module_layout *layout,
 			int (*set_memory)(unsigned long start, int num_pages))
 {
-	BUG_ON(!PAGE_ALIGNED(layout->base));
-	BUG_ON(!PAGE_ALIGNED(layout->ro_after_init_size));
-	BUG_ON(!PAGE_ALIGNED(layout->size));
 	set_memory((unsigned long)layout->base + layout->ro_after_init_size,
 		   (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
 }
 
+static bool layout_check_misalignment(const struct module_layout *layout)
+{
+	return WARN_ON(!PAGE_ALIGNED(layout->base)) ||
+	       WARN_ON(!PAGE_ALIGNED(layout->text_size)) ||
+	       WARN_ON(!PAGE_ALIGNED(layout->ro_size)) ||
+	       WARN_ON(!PAGE_ALIGNED(layout->ro_after_init_size)) ||
+	       WARN_ON(!PAGE_ALIGNED(layout->size));
+}
+
+bool module_check_misalignment(const struct module *mod)
+{
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
+		return false;
+
+	return layout_check_misalignment(&mod->core_layout) ||
+	       layout_check_misalignment(&mod->data_layout) ||
+	       layout_check_misalignment(&mod->init_layout);
+}
+
 void module_enable_x(const struct module *mod)
 {
 	if (!PAGE_ALIGNED(mod->core_layout.base) ||
-- 
2.34.1

[PATCH v2 4/4] module: Rename debug_align() as strict_align()

[Christophe Leroy]

debug_align() was added by commit 84e1c6bb38eb ("x86: Add RO/NX
protection for loadable kernel modules")

At that time the config item was CONFIG_DEBUG_SET_MODULE_RONX.

But nowadays it has changed to CONFIG_STRICT_MODULE_RWX and
debug_align() is confusing because it has nothing to do with
DEBUG.

Rename it strict_align()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 kernel/module/internal.h |  4 ++--
 kernel/module/kallsyms.c |  4 ++--
 kernel/module/main.c     | 14 +++++++-------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index f3dcd40f300c..3e23bef5884d 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -30,9 +30,9 @@
  * only when CONFIG_STRICT_MODULE_RWX=y
  */
 #ifdef CONFIG_STRICT_MODULE_RWX
-# define debug_align(X) PAGE_ALIGN(X)
+# define strict_align(X) PAGE_ALIGN(X)
 #else
-# define debug_align(X) (X)
+# define strict_align(X) (X)
 #endif
 
 extern struct mutex module_mutex;
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
index 850cc66bb28c..c56de1686172 100644
--- a/kernel/module/kallsyms.c
+++ b/kernel/module/kallsyms.c
@@ -139,7 +139,7 @@ void layout_symtab(struct module *mod, struct load_info *info)
 	mod->data_layout.size += strtab_size;
 	info->core_typeoffs = mod->data_layout.size;
 	mod->data_layout.size += ndst * sizeof(char);
-	mod->data_layout.size = debug_align(mod->data_layout.size);
+	mod->data_layout.size = strict_align(mod->data_layout.size);
 
 	/* Put string table section at end of init part of module. */
 	strsect->sh_flags |= SHF_ALLOC;
@@ -154,7 +154,7 @@ void layout_symtab(struct module *mod, struct load_info *info)
 	mod->init_layout.size += sizeof(struct mod_kallsyms);
 	info->init_typeoffs = mod->init_layout.size;
 	mod->init_layout.size += nsrc * sizeof(char);
-	mod->init_layout.size = debug_align(mod->init_layout.size);
+	mod->init_layout.size = strict_align(mod->init_layout.size);
 }
 
 /*
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 4876e2beb5b6..ce0ef17662c9 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1470,19 +1470,19 @@ static void layout_sections(struct module *mod, struct load_info *info)
 		}
 		switch (m) {
 		case 0: /* executable */
-			mod->core_layout.size = debug_align(mod->core_layout.size);
+			mod->core_layout.size = strict_align(mod->core_layout.size);
 			mod->core_layout.text_size = mod->core_layout.size;
 			break;
 		case 1: /* RO: text and ro-data */
-			mod->data_layout.size = debug_align(mod->data_layout.size);
+			mod->data_layout.size = strict_align(mod->data_layout.size);
 			mod->data_layout.ro_size = mod->data_layout.size;
 			break;
 		case 2: /* RO after init */
-			mod->data_layout.size = debug_align(mod->data_layout.size);
+			mod->data_layout.size = strict_align(mod->data_layout.size);
 			mod->data_layout.ro_after_init_size = mod->data_layout.size;
 			break;
 		case 4: /* whole core */
-			mod->data_layout.size = debug_align(mod->data_layout.size);
+			mod->data_layout.size = strict_align(mod->data_layout.size);
 			break;
 		}
 	}
@@ -1504,11 +1504,11 @@ static void layout_sections(struct module *mod, struct load_info *info)
 		}
 		switch (m) {
 		case 0: /* executable */
-			mod->init_layout.size = debug_align(mod->init_layout.size);
+			mod->init_layout.size = strict_align(mod->init_layout.size);
 			mod->init_layout.text_size = mod->init_layout.size;
 			break;
 		case 1: /* RO: text and ro-data */
-			mod->init_layout.size = debug_align(mod->init_layout.size);
+			mod->init_layout.size = strict_align(mod->init_layout.size);
 			mod->init_layout.ro_size = mod->init_layout.size;
 			break;
 		case 2:
@@ -1519,7 +1519,7 @@ static void layout_sections(struct module *mod, struct load_info *info)
 			mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
 			break;
 		case 4: /* whole init */
-			mod->init_layout.size = debug_align(mod->init_layout.size);
+			mod->init_layout.size = strict_align(mod->init_layout.size);
 			break;
 		}
 	}
-- 
2.34.1

Re: [PATCH v2 0/4] Miscellaneous cleanups

[Christophe Leroy]

Le 22/02/2022 à 16:12, Christophe Leroy a écrit :
> This series applies on top of my series "Allocate module text and data separately" v5.
> 
> It does some cleanup around the settling of modules's layout page flags:
> - Make module_enable_x() independent of CONFIG_ARCH_HAS_STRICT_MODULE_RWX
> - Reunify everything into strict_rwx.c
> - Change big hammer BUG_ON()s into WARN_ON()s
> - Change misleading debug_align() to strict_align()

Seems like I made a big mess with v2.

I will resend it as v3.

Sorry for that.

Christophe

> 
> Changes in v2:
> - Rebased on top of my series "Allocate module text and data separately" v5
> - Moved the Kconfig patch out of this series, it is an independent change
> 
> Christophe Leroy (4):
>    module: Make module_enable_x() independent of
>      CONFIG_ARCH_HAS_STRICT_MODULE_RWX
>    module: Move module_enable_x() and frob_text() in strict_rwx.c
>    module: Rework layout alignment to avoid BUG_ON()s
>    module: Rename debug_align() as strict_align()
> 
>   kernel/module/Makefile     |  3 +-
>   kernel/module/internal.h   | 26 +++----------
>   kernel/module/kallsyms.c   |  4 +-
>   kernel/module/main.c       | 58 ++++++-----------------------
>   kernel/module/strict_rwx.c | 76 +++++++++++++++++++++++++++++++++-----
>   5 files changed, 88 insertions(+), 79 deletions(-)
>