The following commit has been merged into the perf/kprobes branch of tip:
Commit-ID: 5e96ce8ae5b1428e6f4953be5fb1daf0a6d18426
Gitweb: https://git.kernel.org/tip/5e96ce8ae5b1428e6f4953be5fb1daf0a6d18426
Author: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
AuthorDate: Sat, 29 Aug 2020 22:02:25 +09:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 08 Sep 2020 11:52:35 +02:00
sparc: kprobes: Use generic kretprobe trampoline handler
Use the generic kretprobe trampoline handler. Don't use
framepointer verification.
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/159870614572.1229682.2273450776108579676.stgit@devnote2
---
arch/sparc/kernel/kprobes.c | 51 ++----------------------------------
1 file changed, 3 insertions(+), 48 deletions(-)
diff --git a/arch/sparc/kernel/kprobes.c b/arch/sparc/kernel/kprobes.c
index dfbca24..217c21a 100644
--- a/arch/sparc/kernel/kprobes.c
+++ b/arch/sparc/kernel/kprobes.c
@@ -453,6 +453,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
{
ri->ret_addr = (kprobe_opcode_t *)(regs->u_regs[UREG_RETPC] + 8);
+ ri->fp = NULL;
/* Replace the return addr with trampoline addr */
regs->u_regs[UREG_RETPC] =
@@ -465,58 +466,12 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
static int __kprobes trampoline_probe_handler(struct kprobe *p,
struct pt_regs *regs)
{
- struct kretprobe_instance *ri = NULL;
- struct hlist_head *head, empty_rp;
- struct hlist_node *tmp;
- unsigned long flags, orig_ret_address = 0;
- unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
+ unsigned long orig_ret_address = 0;
- INIT_HLIST_HEAD(&empty_rp);
- kretprobe_hash_lock(current, &head, &flags);
-
- /*
- * It is possible to have multiple instances associated with a given
- * task either because an multiple functions in the call path
- * have a return probe installed on them, and/or more than one return
- * return probe was registered for a target function.
- *
- * We can handle this because:
- * - instances are always inserted at the head of the list
- * - when multiple return probes are registered for the same
- * function, the first instance's ret_addr will point to the
- * real return address, and all the rest will point to
- * kretprobe_trampoline
- */
- hlist_for_each_entry_safe(ri, tmp, head, hlist) {
- if (ri->task != current)
- /* another task is sharing our hash bucket */
- continue;
-
- if (ri->rp && ri->rp->handler)
- ri->rp->handler(ri, regs);
-
- orig_ret_address = (unsigned long)ri->ret_addr;
- recycle_rp_inst(ri, &empty_rp);
-
- if (orig_ret_address != trampoline_address)
- /*
- * This is the real return address. Any other
- * instances associated with this task are for
- * other calls deeper on the call stack
- */
- break;
- }
-
- kretprobe_assert(ri, orig_ret_address, trampoline_address);
+ orig_ret_address = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL);
regs->tpc = orig_ret_address;
regs->tnpc = orig_ret_address + 4;
- kretprobe_hash_unlock(current, &flags);
-
- hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
- hlist_del(&ri->hlist);
- kfree(ri);
- }
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we don't want the post_handler
|