kernel-fxtec-pro1x/arch/arm/kernel/jump_label.c
Rabin Vincent ab0615e2d6 arm: use fixmap for text patching when text is RO
Use fixmaps for text patching when the kernel text is read-only,
inspired by x86.  This makes jump labels and kprobes work with the
currently available CONFIG_DEBUG_SET_MODULE_RONX and the upcoming
CONFIG_DEBUG_RODATA options.

Signed-off-by: Rabin Vincent <rabin@rab.in>
[kees: fixed up for merge with "arm: use generic fixmap.h"]
[kees: added parse acquire/release annotations to pass C=1 builds]
[kees: always use stop_machine to keep TLB flushing local]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16 14:38:53 -07:00

39 lines
808 B
C

#include <linux/kernel.h>
#include <linux/jump_label.h>
#include "insn.h"
#include "patch.h"
#ifdef HAVE_JUMP_LABEL
static void __arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type,
bool is_static)
{
void *addr = (void *)entry->code;
unsigned int insn;
if (type == JUMP_LABEL_ENABLE)
insn = arm_gen_branch(entry->code, entry->target);
else
insn = arm_gen_nop();
if (is_static)
__patch_text_early(addr, insn);
else
patch_text(addr, insn);
}
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
__arch_jump_label_transform(entry, type, false);
}
void arch_jump_label_transform_static(struct jump_entry *entry,
enum jump_label_type type)
{
__arch_jump_label_transform(entry, type, true);
}
#endif