From: Masami Hiramatsu <mhiramat@kernel.org>
To: linux-kernel@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>
Cc: Eddy_Wu@trendmicro.com, x86@kernel.org, davem@davemloft.net,
rostedt@goodmis.org, naveen.n.rao@linux.ibm.com,
anil.s.keshavamurthy@intel.com, linux-arch@vger.kernel.org,
cameron@moodycamel.com, oleg@redhat.com, will@kernel.org,
paulmck@kernel.org, mhiramat@kernel.org
Subject: [PATCH v4 07/23] ia64: kprobes: Use generic kretprobe trampoline handler
Date: Fri, 28 Aug 2020 21:27:55 +0900 [thread overview]
Message-ID: <159861767492.992023.13013086261920438450.stgit@devnote2> (raw)
In-Reply-To: <159861759775.992023.12553306821235086809.stgit@devnote2>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
arch/ia64/kernel/kprobes.c | 77 +-------------------------------------------
1 file changed, 2 insertions(+), 75 deletions(-)
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 7a7df944d798..fc1ff8a4d7de 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -396,83 +396,9 @@ static void kretprobe_trampoline(void)
{
}
-/*
- * At this point the target function has been tricked into
- * returning into our trampoline. Lookup the associated instance
- * and then:
- * - call the handler function
- * - cleanup by marking the instance as unused
- * - long jump back to the original return address
- */
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 =
- ((struct fnptr *)kretprobe_trampoline)->ip;
-
- 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;
-
- orig_ret_address = (unsigned long)ri->ret_addr;
- 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;
- }
-
- regs->cr_iip = orig_ret_address;
-
- 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);
-
- kretprobe_hash_unlock(current, &flags);
-
- hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
- hlist_del(&ri->hlist);
- kfree(ri);
- }
+ regs->cr_iip = __kretprobe_trampoline_handler(regs, kretprobe_trampoline, NULL);
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we don't want the post_handler
@@ -485,6 +411,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
{
ri->ret_addr = (kprobe_opcode_t *)regs->b0;
+ ri->fp = NULL;
/* Replace the return addr with trampoline addr */
regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip;
next prev parent reply other threads:[~2020-08-28 12:29 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-28 12:26 [PATCH v4 00/23] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Masami Hiramatsu
2020-08-28 12:26 ` [PATCH v4 01/23] kprobes: Add generic kretprobe trampoline handler Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 02/23] x86/kprobes: Use " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 03/23] arm: kprobes: " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 04/23] arm64: " Masami Hiramatsu
2020-08-28 13:31 ` Mark Rutland
2020-08-28 13:37 ` peterz
2020-08-28 13:48 ` Mark Rutland
2020-08-28 13:58 ` Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 05/23] arc: " Masami Hiramatsu
2020-08-28 12:27 ` [PATCH v4 06/23] csky: " Masami Hiramatsu
2020-08-28 12:27 ` Masami Hiramatsu [this message]
2020-08-28 12:28 ` [PATCH v4 08/23] mips: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 09/23] parisc: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 10/23] powerpc: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 11/23] s390: " Masami Hiramatsu
2020-08-28 12:28 ` [PATCH v4 12/23] sh: " Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 13/23] sparc: " Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 14/23] kprobes: Remove NMI context check Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 15/23] kprobes: Free kretprobe_instance with rcu callback Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 16/23] kprobes: Make local used functions static Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 17/23] llist: Add nonatomic __llist_add() Masami Hiramatsu
2020-08-28 12:29 ` [PATCH v4 18/23] sched: Fix try_invoke_on_locked_down_task() semantics Masami Hiramatsu
2020-08-29 2:01 ` Masami Hiramatsu
2020-08-29 7:30 ` peterz
2020-08-29 17:31 ` Paul E. McKenney
2020-08-28 12:30 ` [PATCH v4 19/23] kprobes: Remove kretprobe hash Masami Hiramatsu
2020-08-28 18:37 ` Masami Hiramatsu
2020-08-28 19:02 ` peterz
2020-08-28 19:32 ` Eddy_Wu
2020-08-28 20:29 ` Peter Zijlstra
2020-08-29 1:23 ` Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 20/23] [RFC] kprobes: Remove task scan for updating kretprobe_instance Masami Hiramatsu
2020-08-28 12:52 ` peterz
2020-08-28 15:10 ` Masami Hiramatsu
2020-08-28 15:18 ` peterz
2020-08-28 16:01 ` Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 21/23] asm-generic/atomic: Add try_cmpxchg() fallbacks Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 22/23] freelist: Lock less freelist Masami Hiramatsu
2020-08-28 12:30 ` [PATCH v4 23/23] kprobes: Replace rp->free_instance with freelist Masami Hiramatsu
2020-08-28 12:37 ` [PATCH v4 00/23] kprobes: Unify kretprobe trampoline handlers and make kretprobe lockless Masami Hiramatsu
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