In preparation for the objtool klp diff subcommand, define the entry
size for the __ex_table section in its ELF header. This will allow
tooling to extract individual entries.
Signed-off-by: Josh Poimboeuf <jpoim...@kernel.org>
---
arch/x86/include/asm/asm.h | 20 ++++++++++++--------
kernel/extable.c | 2 ++
2 files changed, 14 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index f963848024a5..62dff336f206 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -138,15 +138,17 @@ static __always_inline __pure void *rip_rel_ptr(void *p)
# include <asm/extable_fixup_types.h>
+#define EXTABLE_SIZE 12
+
/* Exception table entry */
#ifdef __ASSEMBLER__
-# define _ASM_EXTABLE_TYPE(from, to, type) \
- .pushsection "__ex_table","a" ; \
- .balign 4 ; \
- .long (from) - . ; \
- .long (to) - . ; \
- .long type ; \
+# define _ASM_EXTABLE_TYPE(from, to, type) \
+ .pushsection "__ex_table", "aM", @progbits, EXTABLE_SIZE; \
+ .balign 4 ; \
+ .long (from) - . ; \
+ .long (to) - . ; \
+ .long type ; \
.popsection
# ifdef CONFIG_KPROBES
@@ -189,7 +191,8 @@ static __always_inline __pure void *rip_rel_ptr(void *p)
".purgem extable_type_reg\n"
# define _ASM_EXTABLE_TYPE(from, to, type) \
- " .pushsection \"__ex_table\",\"a\"\n" \
+ " .pushsection __ex_table, \"aM\", @progbits, " \
+ __stringify(EXTABLE_SIZE) "\n" \
" .balign 4\n" \
" .long (" #from ") - .\n" \
" .long (" #to ") - .\n" \
@@ -197,7 +200,8 @@ static __always_inline __pure void *rip_rel_ptr(void *p)
" .popsection\n"
# define _ASM_EXTABLE_TYPE_REG(from, to, type, reg)
\
- " .pushsection \"__ex_table\",\"a\"\n"
\
+ " .pushsection __ex_table, \"aM\", @progbits, "
\
+ __stringify(EXTABLE_SIZE) "\n"
\
" .balign 4\n"
\
" .long (" #from ") - .\n"
\
" .long (" #to ") - .\n"
\
diff --git a/kernel/extable.c b/kernel/extable.c
index 71f482581cab..0ae3ee2ef266 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -55,6 +55,8 @@ const struct exception_table_entry
*search_exception_tables(unsigned long addr)
{
const struct exception_table_entry *e;
+ BUILD_BUG_ON(EXTABLE_SIZE != sizeof(struct exception_table_entry));
+
e = search_kernel_exception_table(addr);
if (!e)
e = search_module_extables(addr);
--
2.49.0
