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authorLinus Torvalds <torvalds@linux-foundation.org>2019-11-26 10:42:40 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-11-26 10:42:40 -0800
commit1d87200446f1d10dfe9672ca8edb027a82612f8c (patch)
tree45cc71ff8e4d1bcde9b07ce8203277f2b8982941 /include/asm-generic
parent5c4a1c090d8676d8b84e2ac40671602be44afdfc (diff)
parentf01ec4fca8207e31b59a010c3de679c833f3a877 (diff)
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - Cross-arch changes to move the linker sections for NOTES and EXCEPTION_TABLE into the RO_DATA area, where they belong on most architectures. (Kees Cook) - Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to trap jumps into the middle of those padding areas instead of sliding execution. (Kees Cook) - A thorough cleanup of symbol definitions within x86 assembler code. The rather randomly named macros got streamlined around a (hopefully) straightforward naming scheme: SYM_START(name, linkage, align...) SYM_END(name, sym_type) SYM_FUNC_START(name) SYM_FUNC_END(name) SYM_CODE_START(name) SYM_CODE_END(name) SYM_DATA_START(name) SYM_DATA_END(name) etc - with about three times of these basic primitives with some label, local symbol or attribute variant, expressed via postfixes. No change in functionality intended. (Jiri Slaby) - Misc other changes, cleanups and smaller fixes" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) x86/entry/64: Remove pointless jump in paranoid_exit x86/entry/32: Remove unused resume_userspace label x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o m68k: Convert missed RODATA to RO_DATA x86/vmlinux: Use INT3 instead of NOP for linker fill bytes x86/mm: Report actual image regions in /proc/iomem x86/mm: Report which part of kernel image is freed x86/mm: Remove redundant address-of operators on addresses xtensa: Move EXCEPTION_TABLE to RO_DATA segment powerpc: Move EXCEPTION_TABLE to RO_DATA segment parisc: Move EXCEPTION_TABLE to RO_DATA segment microblaze: Move EXCEPTION_TABLE to RO_DATA segment ia64: Move EXCEPTION_TABLE to RO_DATA segment h8300: Move EXCEPTION_TABLE to RO_DATA segment c6x: Move EXCEPTION_TABLE to RO_DATA segment arm64: Move EXCEPTION_TABLE to RO_DATA segment alpha: Move EXCEPTION_TABLE to RO_DATA segment x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment x86/vmlinux: Actually use _etext for the end of the text segment vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA ...
Diffstat (limited to 'include/asm-generic')
-rw-r--r--include/asm-generic/vmlinux.lds.h53
1 files changed, 39 insertions, 14 deletions
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index a9c4e4721434..63cedc3c0c77 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -23,12 +23,11 @@
* _etext = .;
*
* _sdata = .;
- * RO_DATA_SECTION(PAGE_SIZE)
- * RW_DATA_SECTION(...)
+ * RO_DATA(PAGE_SIZE)
+ * RW_DATA(...)
* _edata = .;
*
* EXCEPTION_TABLE(...)
- * NOTES
*
* BSS_SECTION(0, 0, 0)
* _end = .;
@@ -54,6 +53,33 @@
#define LOAD_OFFSET 0
#endif
+/*
+ * Only some architectures want to have the .notes segment visible in
+ * a separate PT_NOTE ELF Program Header. When this happens, it needs
+ * to be visible in both the kernel text's PT_LOAD and the PT_NOTE
+ * Program Headers. In this case, though, the PT_LOAD needs to be made
+ * the default again so that all the following sections don't also end
+ * up in the PT_NOTE Program Header.
+ */
+#ifdef EMITS_PT_NOTE
+#define NOTES_HEADERS :text :note
+#define NOTES_HEADERS_RESTORE __restore_ph : { *(.__restore_ph) } :text
+#else
+#define NOTES_HEADERS
+#define NOTES_HEADERS_RESTORE
+#endif
+
+/*
+ * Some architectures have non-executable read-only exception tables.
+ * They can be added to the RO_DATA segment by specifying their desired
+ * alignment.
+ */
+#ifdef RO_EXCEPTION_TABLE_ALIGN
+#define RO_EXCEPTION_TABLE EXCEPTION_TABLE(RO_EXCEPTION_TABLE_ALIGN)
+#else
+#define RO_EXCEPTION_TABLE
+#endif
+
/* Align . to a 8 byte boundary equals to maximum function alignment. */
#define ALIGN_FUNCTION() . = ALIGN(8)
@@ -348,7 +374,7 @@
/*
* Read only Data
*/
-#define RO_DATA_SECTION(align) \
+#define RO_DATA(align) \
. = ALIGN((align)); \
.rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \
__start_rodata = .; \
@@ -496,15 +522,13 @@
__start___modver = .; \
KEEP(*(__modver)) \
__stop___modver = .; \
- . = ALIGN((align)); \
- __end_rodata = .; \
} \
- . = ALIGN((align));
-
-/* RODATA & RO_DATA provided for backward compatibility.
- * All archs are supposed to use RO_DATA() */
-#define RODATA RO_DATA_SECTION(4096)
-#define RO_DATA(align) RO_DATA_SECTION(align)
+ \
+ RO_EXCEPTION_TABLE \
+ NOTES \
+ \
+ . = ALIGN((align)); \
+ __end_rodata = .;
/*
* .text section. Map to function alignment to avoid address changes
@@ -790,7 +814,8 @@
__start_notes = .; \
KEEP(*(.note.*)) \
__stop_notes = .; \
- }
+ } NOTES_HEADERS \
+ NOTES_HEADERS_RESTORE
#define INIT_SETUP(initsetup_align) \
. = ALIGN(initsetup_align); \
@@ -962,7 +987,7 @@
* matches the requirement of PAGE_ALIGNED_DATA.
*
* use 0 as page_align if page_aligned data is not used */
-#define RW_DATA_SECTION(cacheline, pagealigned, inittask) \
+#define RW_DATA(cacheline, pagealigned, inittask) \
. = ALIGN(PAGE_SIZE); \
.data : AT(ADDR(.data) - LOAD_OFFSET) { \
INIT_TASK_DATA(inittask) \