Currently all instructions have the same length, but in preparation for
prefixed instructions introduce a function for returning instruction
length.
Reviewed-by: Alistair Popple <alist...@popple.id.au>
Signed-off-by: Jordan Niethe <jniet...@gmail.com>
---
v6: - feature-fixups.c: do_final_fixups(): use here
- ppc_inst_len(): change return type from bool to int
- uprobes: Use ppc_inst_read() before calling ppc_inst_len()
---
arch/powerpc/include/asm/inst.h | 5 +++++
arch/powerpc/kernel/kprobes.c | 6 ++++--
arch/powerpc/kernel/uprobes.c | 2 +-
arch/powerpc/lib/feature-fixups.c | 14 +++++++-------
4 files changed, 17 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h
index 0d581b332c20..2f3c9d5bcf7c 100644
--- a/arch/powerpc/include/asm/inst.h
+++ b/arch/powerpc/include/asm/inst.h
@@ -17,6 +17,11 @@ static inline u32 ppc_inst_val(struct ppc_inst x)
return x.val;
}
+static inline int ppc_inst_len(struct ppc_inst x)
+{
+ return sizeof(struct ppc_inst);
+}
+
static inline int ppc_inst_primary_opcode(struct ppc_inst x)
{
return ppc_inst_val(x) >> 26;
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index a72c8e1a42ad..33d54b091c70 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -462,14 +462,16 @@ NOKPROBE_SYMBOL(trampoline_probe_handler);
*/
int kprobe_post_handler(struct pt_regs *regs)
{
+ int len;
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
if (!cur || user_mode(regs))
return 0;
+ len = ppc_inst_len(ppc_inst_read((struct ppc_inst *)cur->ainsn.insn));
/* make sure we got here for instruction we have a kprobe on */
- if (((unsigned long)cur->ainsn.insn + 4) != regs->nip)
+ if (((unsigned long)cur->ainsn.insn + len) != regs->nip)
return 0;
if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
@@ -478,7 +480,7 @@ int kprobe_post_handler(struct pt_regs *regs)
}
/* Adjust nip to after the single-stepped instruction */
- regs->nip = (unsigned long)cur->addr + 4;
+ regs->nip = (unsigned long)cur->addr + len;
regs->msr |= kcb->kprobe_saved_msr;
/*Restore back the original saved kprobes variables and continue. */
diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
index 6893d40a48c5..83e883e1a42d 100644
--- a/arch/powerpc/kernel/uprobes.c
+++ b/arch/powerpc/kernel/uprobes.c
@@ -112,7 +112,7 @@ int arch_uprobe_post_xol(struct arch_uprobe *auprobe,
struct pt_regs *regs)
* support doesn't exist and have to fix-up the next instruction
* to be executed.
*/
- regs->nip = utask->vaddr + MAX_UINSN_BYTES;
+ regs->nip = utask->vaddr + ppc_inst_len(ppc_inst_read(&auprobe->insn));
user_disable_single_step(current);
return 0;
diff --git a/arch/powerpc/lib/feature-fixups.c
b/arch/powerpc/lib/feature-fixups.c
index c0d3ed4efb7e..2bd2b752de4f 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -392,20 +392,20 @@ void do_lwsync_fixups(unsigned long value, void
*fixup_start, void *fixup_end)
static void do_final_fixups(void)
{
#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
- struct ppc_inst *src, *dest;
- unsigned long length;
+ struct ppc_inst inst, *src, *dest, *end;
if (PHYSICAL_START == 0)
return;
src = (struct ppc_inst *)(KERNELBASE + PHYSICAL_START);
dest = (struct ppc_inst *)KERNELBASE;
- length = (__end_interrupts - _stext) / sizeof(struct ppc_inst);
+ end = (void *)src + (__end_interrupts - _stext);
- while (length--) {
- raw_patch_instruction(dest, ppc_inst_read(src));
- src++;
- dest++;
+ while (src < end) {
+ inst = ppc_inst_read(src);
+ raw_patch_instruction(dest, inst);
+ src = (void *)src + ppc_inst_len(inst);
+ dest = (void *)dest + ppc_inst_len(inst);
}
#endif
}
--
2.17.1
