init/modpost: conditionally check section mismatch to __meminit*

This reverts commit eb8f689046b8 ("Use separate sections for __dev/ _cpu/__mem code/data"). Check section mismatch to __meminit* only when CONFIG_MEMORY_HOTPLUG=n. With this change, the linker script and modpost become simpler, and we can get rid of the __ref annotations from the memory hotplug code. [sfr@canb.auug.org.au: remove MEM_KEEP from arch/powerpc/kernel/vmlinux.lds.S] Link: https://lkml.kernel.org/r/20240710093213.2aefb25f@canb.auug.org.au Link: https://lkml.kernel.org/r/20240706160511.2331061-2-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Masahiro Yamada committed 2 years ago

Commit 73db3ab1 parent 7a7127a4 files · +15 −38Browse files

Unified · Split

4 files

arch/powerpc/kernel/vmlinux.lds.S +0 −2
include/asm-generic/vmlinux.lds.h +2 −16
include/linux/init.h +9 −5
scripts/mod/modpost.c +4 −15

arch/powerpc/kernel/vmlinux.lds.S+0−2

@@ -123,8 +123,6 @@ SECTIONS · 122 unmodified lines
123	*/	123	*/
124	*(.sfpr);	124	*(.sfpr);
125	(.text.asan. .text.tsan.*)	125	(.text.asan. .text.tsan.*)
126	MEM_KEEP(init.text)
127	MEM_KEEP(exit.text)
128	} :text	126	} :text
129		127
130	. = ALIGN(PAGE_SIZE);	128	. = ALIGN(PAGE_SIZE);

include/asm-generic/vmlinux.lds.h+2−16

  * often happens at runtime)
  */
-#if defined(CONFIG_MEMORY_HOTPLUG)
-#define MEM_KEEP(sec)    *(.mem##sec)
-#define MEM_DISCARD(sec)
-#else
-#define MEM_KEEP(sec)
-#define MEM_DISCARD(sec) *(.mem##sec)
-#endif
 #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
 #define KEEP_PATCHABLE		KEEP(*(__patchable_function_entries))
 #define PATCHABLE_DISCARDS
 	*(.data..decrypted)						\
 	*(.ref.data)							\
 	*(.data..shared_aligned) /* percpu related */			\
-	MEM_KEEP(init.data*)						\
 	*(.data.unlikely)						\
 	__start_once = .;						\
 	*(.data.once)							\
 	/* __*init sections */						\
 	__init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) {		\
 		*(.ref.rodata)						\
-		MEM_KEEP(init.rodata)					\
 	}								\
 									\
 	/* Built-in module parameters. */				\
 		*(.text.unknown .text.unknown.*)			\
 		NOINSTR_TEXT						\
 		*(.ref.text)						\
-		*(.text.asan.* .text.tsan.*)				\
+		*(.text.asan.* .text.tsan.*)
-	MEM_KEEP(init.text*)						\
 /* sched.text is aling to function alignment to secure we have same
 #define INIT_DATA							\
 	KEEP(*(SORT(___kentry+*)))					\
 	*(.init.data .init.data.*)					\
-	MEM_DISCARD(init.data*)						\
 	KERNEL_CTORS()							\
 	MCOUNT_REC()							\
 	*(.init.rodata .init.rodata.*)					\
 	TRACE_SYSCALLS()						\
 	KPROBE_BLACKLIST()						\
 	ERROR_INJECT_WHITELIST()					\
-	MEM_DISCARD(init.rodata)					\
 	CLK_OF_TABLES()							\
 	RESERVEDMEM_OF_TABLES()						\
 	TIMER_OF_TABLES()						\
 #define INIT_TEXT							\
 	*(.init.text .init.text.*)					\
-	*(.text.startup)						\
+	*(.text.startup)
-	MEM_DISCARD(init.text*)
 #define EXIT_DATA							\
 	*(.exit.data .exit.data.*)					\

include/linux/init.h+9−5

@@ -84,11 +84,15 @@ · 83 unmodified lines
84		84
85	#define __exit __section(".exit.text") __exitused __cold notrace	85	#define __exit __section(".exit.text") __exitused __cold notrace
86		86
87	/* Used for MEMORY_HOTPLUG */	87	#ifdef CONFIG_MEMORY_HOTPLUG
88	#define __meminit __section(".meminit.text") __cold notrace \	88	#define __meminit
89	__latent_entropy	89	#define __meminitdata
90	#define __meminitdata __section(".meminit.data")	90	#define __meminitconst
91	#define __meminitconst __section(".meminit.rodata")	91	#else
		92	#define __meminit __init
		93	#define __meminitdata __initdata
		94	#define __meminitconst __initconst
		95	#endif
92		96
93	/* For assembly routines */	97	/* For assembly routines */
94	#define __HEAD .section ".head.text","ax"	98	#define __HEAD .section ".head.text","ax"

scripts/mod/modpost.c+4−15

 #define ALL_INIT_DATA_SECTIONS \
-	".init.setup", ".init.rodata", ".meminit.rodata", \
+	".init.setup", ".init.rodata", ".init.data"
-	".init.data", ".meminit.data"
 #define ALL_PCI_INIT_SECTIONS	\
 	".pci_fixup_early", ".pci_fixup_header", ".pci_fixup_final", \
 	".pci_fixup_enable", ".pci_fixup_resume", \
 	".pci_fixup_resume_early", ".pci_fixup_suspend"
-#define ALL_XXXINIT_SECTIONS ".meminit.*"
+#define ALL_INIT_SECTIONS ".init.*"
-#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
 #define ALL_EXIT_SECTIONS ".exit.*"
 #define DATA_SECTIONS ".data", ".data.rel"
 		".fixup", ".entry.text", ".exception.text", \
 		".coldtext", ".softirqentry.text"
-#define INIT_SECTIONS      ".init.*"
+#define ALL_TEXT_SECTIONS  ".init.text", ".exit.text", \
-#define ALL_TEXT_SECTIONS  ".init.text", ".meminit.text", ".exit.text", \
 		TEXT_SECTIONS, OTHER_TEXT_SECTIONS
 enum mismatch {
 	.bad_tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL },
 	.mismatch = TEXTDATA_TO_ANY_INIT_EXIT,
 },
-/* Do not reference init code/data from meminit code/data */
-{
-	.fromsec = { ALL_XXXINIT_SECTIONS, NULL },
-	.bad_tosec = { INIT_SECTIONS, NULL },
-	.mismatch = XXXINIT_TO_SOME_INIT,
-},
 /* Do not use exit code/data from init code */
 {
 	.fromsec = { ALL_INIT_SECTIONS, NULL },
 },
 {
 	.fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
-	.bad_tosec = { INIT_SECTIONS, NULL },
+	.bad_tosec = { ALL_INIT_SECTIONS, NULL },
 	.mismatch = ANY_INIT_TO_ANY_EXIT,
 },
 {