From: peterz@infradead.org (Peter Zijlstra)
Subject: [RFC][PATCH] ftrace/x86: Emulate call function while updating in breakpoint handler
Date: Wed, 1 May 2019 21:03:48 +0200 [thread overview]
Message-ID: <20190501190348.GT7905@worktop.programming.kicks-ass.net> (raw)
Message-ID: <20190501190348.5tLjoxW5bQlReh6sY93xMEyDlRnfQDeQmwUwZFFKPmo@z> (raw)
In-Reply-To: <20190501145824.08aed43a@gandalf.local.home>
On Wed, May 01, 2019@02:58:24PM -0400, Steven Rostedt wrote:
> > + if (ftrace_location(ip)) {
> > + int3_emulate_call(regs, ftrace_update_func_call);
>
> Should be:
>
> int3_emulate_call(regs, (unsigned long)ftrace_regs_caller);
Ah, I lost the plot a little there.
> > + return 1;
> > + } else if (is_ftrace_caller(ip)) {
> > + if (!ftrace_update_func_call) {
> > + int3_emulate_jmp(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
>
> I see what you did here, but I think:
>
> int3_emulate_jmp(regs, ip + CALL_INSN_SIZE);
>
> looks better. But that said, we could in the beginning do:
>
> ip = regs->ip - INT3_INSN_SIZE;
>
> instead of
>
> ip = regs->ip - 1;
>
> I made these updates and posted them to Linus.
I was actually considering:
static inline void int3_emulate_nop(struct pt_regs *regs, unsigned long size)
{
int3_emulate_jmp(regs, regs->ip - INT3_INSN_SIZE + size);
}
And then the above becomes:
int3_emulate_nop(regs, CALL_INSN_SIZE);
Hmm?
next prev parent reply other threads:[~2019-05-01 19:03 UTC|newest]
Thread overview: 128+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-27 10:06 [PATCH 0/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation nstange
2019-04-27 10:06 ` Nicolai Stange
2019-04-27 10:06 ` [PATCH 1/4] x86/thread_info: introduce ->ftrace_int3_stack member nstange
2019-04-27 10:06 ` Nicolai Stange
2019-04-28 17:41 ` luto
2019-04-28 17:41 ` Andy Lutomirski
2019-04-28 17:51 ` rostedt
2019-04-28 17:51 ` Steven Rostedt
2019-04-28 18:08 ` luto
2019-04-28 18:08 ` Andy Lutomirski
2019-04-28 19:43 ` rostedt
2019-04-28 19:43 ` Steven Rostedt
2019-04-28 20:56 ` luto
2019-04-28 20:56 ` Andy Lutomirski
2019-04-28 21:22 ` nstange
2019-04-28 21:22 ` Nicolai Stange
2019-04-28 23:27 ` luto
2019-04-28 23:27 ` Andy Lutomirski
2019-04-27 10:06 ` [PATCH 2/4] ftrace: drop 'static' qualifier from ftrace_ops_list_func() nstange
2019-04-27 10:06 ` Nicolai Stange
2019-04-27 10:06 ` [PATCH 3/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation nstange
2019-04-27 10:06 ` Nicolai Stange
2019-04-27 10:26 ` peterz
2019-04-27 10:26 ` Peter Zijlstra
2019-04-28 17:38 ` rostedt
2019-04-28 17:38 ` Steven Rostedt
2019-04-29 18:06 ` torvalds
2019-04-29 18:06 ` Linus Torvalds
2019-04-29 18:22 ` torvalds
2019-04-29 18:22 ` Linus Torvalds
2019-04-29 18:42 ` luto
2019-04-29 18:42 ` Andy Lutomirski
[not found] ` <CAHk-=whtt4K2f0KPtG-4Pykh3FK8UBOjD8jhXCUKB5nWDj_YRA@mail.gmail.com>
2019-04-29 18:56 ` luto
2019-04-29 18:56 ` Andy Lutomirski
[not found] ` <CAHk-=wgewK4eFhF3=0RNtk1KQjMANFH6oDE=8m=84RExn2gxhw@mail.gmail.com>
[not found] ` <CAHk-=whay7eN6+2gZjY-ybRbkbcqAmgrLwwszzHx8ws3c=S-MA@mail.gmail.com>
2019-04-29 19:24 ` luto
2019-04-29 19:24 ` Andy Lutomirski
2019-04-29 20:07 ` torvalds
2019-04-29 20:07 ` Linus Torvalds
2019-04-30 13:56 ` peterz
2019-04-30 13:56 ` Peter Zijlstra
2019-04-30 16:06 ` torvalds
2019-04-30 16:06 ` Linus Torvalds
2019-04-30 16:33 ` luto
2019-04-30 16:33 ` Andy Lutomirski
2019-04-30 17:03 ` rostedt
2019-04-30 17:03 ` Steven Rostedt
2019-04-30 17:20 ` rostedt
2019-04-30 17:20 ` Steven Rostedt
2019-04-30 17:49 ` [RFC][PATCH] ftrace/x86: Emulate call function while updating in breakpoint handler rostedt
2019-04-30 17:49 ` Steven Rostedt
2019-04-30 18:33 ` torvalds
2019-04-30 18:33 ` Linus Torvalds
2019-04-30 19:00 ` rostedt
2019-04-30 19:00 ` Steven Rostedt
2019-04-30 21:08 ` rostedt
2019-04-30 21:08 ` Steven Rostedt
2019-05-01 13:11 ` peterz
2019-05-01 13:11 ` Peter Zijlstra
2019-05-01 18:58 ` rostedt
2019-05-01 18:58 ` Steven Rostedt
2019-05-01 19:03 ` peterz [this message]
2019-05-01 19:03 ` Peter Zijlstra
2019-05-01 19:03 ` torvalds
2019-05-01 19:03 ` Linus Torvalds
2019-05-01 19:13 ` peterz
2019-05-01 19:13 ` Peter Zijlstra
2019-05-01 19:13 ` rostedt
2019-05-01 19:13 ` Steven Rostedt
2019-05-01 19:33 ` jikos
2019-05-01 19:33 ` Jiri Kosina
2019-05-01 19:41 ` peterz
2019-05-01 19:41 ` Peter Zijlstra
2019-04-30 21:53 ` [RFC][PATCH v2] " rostedt
2019-04-30 21:53 ` Steven Rostedt
2019-05-01 1:35 ` rostedt
2019-05-01 1:35 ` Steven Rostedt
2019-05-01 1:58 ` torvalds
2019-05-01 1:58 ` Linus Torvalds
2019-05-01 8:26 ` nstange
2019-05-01 8:26 ` Nicolai Stange
2019-05-01 13:22 ` rostedt
2019-05-01 13:22 ` Steven Rostedt
2019-04-29 20:16 ` [PATCH 3/4] x86/ftrace: make ftrace_int3_handler() not to skip fops invocation torvalds
2019-04-29 20:16 ` Linus Torvalds
2019-04-29 22:08 ` sean.j.christopherson
2019-04-29 22:08 ` Sean Christopherson
2019-04-29 22:22 ` torvalds
2019-04-29 22:22 ` Linus Torvalds
2019-04-30 0:08 ` sean.j.christopherson
2019-04-30 0:08 ` Sean Christopherson
2019-04-30 0:45 ` sean.j.christopherson
2019-04-30 0:45 ` Sean Christopherson
2019-04-30 2:26 ` torvalds
2019-04-30 2:26 ` Linus Torvalds
2019-04-30 10:40 ` peterz
2019-04-30 10:40 ` Peter Zijlstra
2019-04-30 11:17 ` jikos
2019-04-30 11:17 ` Jiri Kosina
2019-04-29 22:06 ` torvalds
2019-04-29 22:06 ` Linus Torvalds
2019-04-30 11:18 ` peterz
2019-04-30 11:18 ` Peter Zijlstra
2019-04-29 18:52 ` rostedt
2019-04-29 18:52 ` Steven Rostedt
[not found] ` <CAHk-=wjm93jLtVxTX4HZs6K4k1Wqh3ujjmapqaYtcibVk_YnzQ@mail.gmail.com>
2019-04-29 19:07 ` rostedt
2019-04-29 19:07 ` Steven Rostedt
2019-04-29 20:06 ` torvalds
2019-04-29 20:06 ` Linus Torvalds
2019-04-29 20:20 ` torvalds
2019-04-29 20:20 ` Linus Torvalds
2019-04-29 20:30 ` rostedt
2019-04-29 20:30 ` Steven Rostedt
2019-04-29 21:38 ` torvalds
2019-04-29 21:38 ` Linus Torvalds
2019-04-29 22:07 ` rostedt
2019-04-29 22:07 ` Steven Rostedt
2019-04-30 9:24 ` nstange
2019-04-30 9:24 ` Nicolai Stange
2019-04-30 10:46 ` peterz
2019-04-30 10:46 ` Peter Zijlstra
2019-04-30 13:44 ` rostedt
2019-04-30 13:44 ` Steven Rostedt
2019-04-30 14:20 ` peterz
2019-04-30 14:20 ` Peter Zijlstra
2019-04-30 14:36 ` rostedt
2019-04-30 14:36 ` Steven Rostedt
2019-04-27 10:06 ` [PATCH 4/4] selftests/livepatch: add "ftrace a live patched function" test nstange
2019-04-27 10:06 ` Nicolai Stange
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