From: Masami Hiramatsu <mhiramat@kernel.org>
To: linux-kernel@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>
Cc: Eddy Wu <Eddy_Wu@trendmicro.com>,
x86@kernel.org, "David S . Miller" <davem@davemloft.net>,
Steven Rostedt <rostedt@goodmis.org>,
Ingo Molnar <mingo@redhat.com>,
"Naveen N . Rao" <naveen.n.rao@linux.ibm.com>,
Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
linux-arch@vger.kernel.org
Subject: [PATCH v2 08/15] mips: kprobes: Use generic kretprobe trampoline handler
Date: Thu, 27 Aug 2020 20:36:39 +0900 [thread overview]
Message-ID: <159852819884.707944.11614246435562634035.stgit@devnote2> (raw)
In-Reply-To: <159852811819.707944.12798182250041968537.stgit@devnote2>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
arch/mips/kernel/kprobes.c | 55 +++-----------------------------------------
1 file changed, 4 insertions(+), 51 deletions(-)
diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c
index d043c2f897fc..b58f49b7555e 100644
--- a/arch/mips/kernel/kprobes.c
+++ b/arch/mips/kernel/kprobes.c
@@ -477,6 +477,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
{
ri->ret_addr = (kprobe_opcode_t *) regs->regs[31];
+ ri->fp = NULL;
/* Replace the return addr with trampoline addr */
regs->regs[31] = (unsigned long)kretprobe_trampoline;
@@ -488,57 +489,9 @@ 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;
-
- 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);
- instruction_pointer(regs) = orig_ret_address;
-
- kretprobe_hash_unlock(current, &flags);
-
- hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
- hlist_del(&ri->hlist);
- kfree(ri);
- }
+ instruction_pointer(regs) = __kretprobe_trampoline_handler(regs,
+ (unsigned long)kretprobe_trampoline,
+ NULL);
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we don't want the post_handler
next prev parent reply other threads:[~2020-08-27 15:18 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-27 11:35 [PATCH v2 00/15] kprobes: Unify kretprobe trampoline handlers Masami Hiramatsu
2020-08-27 11:35 ` [PATCH v2 01/15] kprobes: Add generic kretprobe trampoline handler Masami Hiramatsu
2020-08-27 11:35 ` [PATCH v2 02/15] x86/kprobes: Use " Masami Hiramatsu
2020-08-27 11:35 ` [PATCH v2 03/15] arm: kprobes: " Masami Hiramatsu
2020-08-27 11:35 ` [PATCH v2 04/15] arm64: " Masami Hiramatsu
2020-08-27 11:36 ` [PATCH v2 05/15] arc: " Masami Hiramatsu
2020-08-27 11:36 ` [PATCH v2 06/15] csky: " Masami Hiramatsu
2020-08-27 11:36 ` [PATCH v2 07/15] ia64: " Masami Hiramatsu
2020-08-27 11:36 ` Masami Hiramatsu [this message]
2020-08-27 11:36 ` [PATCH v2 09/15] parisc: " Masami Hiramatsu
2020-08-27 11:36 ` [PATCH v2 10/15] powerpc: " Masami Hiramatsu
2020-08-27 11:37 ` [PATCH v2 11/15] s390: " Masami Hiramatsu
2020-08-27 11:37 ` [PATCH v2 12/15] sh: " Masami Hiramatsu
2020-08-27 11:37 ` [PATCH v2 13/15] sparc: " Masami Hiramatsu
2020-08-27 11:37 ` [PATCH v2 14/15] kprobes: Remove NMI context check Masami Hiramatsu
2020-08-27 11:37 ` [PATCH v2 15/15] kprobes: Free kretprobe_instance with rcu callback Masami Hiramatsu
2020-08-27 11:48 ` peterz
2020-08-27 11:50 ` Masami Hiramatsu
2020-08-27 11:49 ` peterz
2020-08-27 13:02 ` Masami Hiramatsu
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