Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-09-20 15:03:04 +00:00
Code Issues Packages Projects Releases Wiki Activity

jump_label, x86: Introduce jump_entry_size()

Browse Source 
This allows architectures to have variable sized jumps.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210506194157.786777050@infradead.org
This commit is contained in:
Peter Zijlstra 2021-05-06 21:33:58 +02:00 committed by Ingo Molnar
parent f9510fa9ca
commit fa5e5dc396
4 changed files with 19 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/x86/include/asm/jump_label.h
View File

@ -4,8 +4,6 @@
#define HAVE_JUMP_LABEL_BATCH
#define JUMP_LABEL_NOP_SIZE 5
#include <asm/asm.h>
#include <asm/nops.h>
@ -47,6 +45,8 @@ l_yes:
return true;
}
extern int arch_jump_entry_size(struct jump_entry *entry);
#endif /* __ASSEMBLY__ */
#endif

7
arch/x86/kernel/jump_label.c
View File

@ -16,6 +16,13 @@
#include <asm/alternative.h>
#include <asm/text-patching.h>
#define JUMP_LABEL_NOP_SIZE JMP32_INSN_SIZE
int arch_jump_entry_size(struct jump_entry *entry)
{
return JMP32_INSN_SIZE;
}
static const void *
__jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type)
{

9
include/linux/jump_label.h
View File

@ -176,6 +176,15 @@ static inline void jump_entry_set_init(struct jump_entry *entry)
entry->key |= 2;
}
static inline int jump_entry_size(struct jump_entry *entry)
{
#ifdef JUMP_LABEL_NOP_SIZE
return JUMP_LABEL_NOP_SIZE;
#else
return arch_jump_entry_size(entry);
#endif
}
#endif
#endif

2
kernel/jump_label.c
View File

@ -309,7 +309,7 @@ EXPORT_SYMBOL_GPL(jump_label_rate_limit);
static int addr_conflict(struct jump_entry *entry, void *start, void *end)
{
if (jump_entry_code(entry) <= (unsigned long)end &&
jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE > (unsigned long)start)
jump_entry_code(entry) + jump_entry_size(entry) > (unsigned long)start)
return 1;
return 0;