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From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Daniel Xu <dxu@dxuuu.xyz>, Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@kernel.org>, X86 ML <x86@kernel.org>,
	linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
	kuba@kernel.org, mingo@redhat.com, ast@kernel.org,
	tglx@linutronix.de, kernel-team@fb.com, yhs@fb.com
Subject: Re: [PATCH -tip 0/5] kprobes: Fix stacktrace in kretprobes
Date: Wed, 10 Mar 2021 09:08:45 -0600	[thread overview]
Message-ID: <20210310150845.7kctaox34yrfyjxt@treble> (raw)
In-Reply-To: <20210310185734.332d9d52a26780ba02d09197@kernel.org>

On Wed, Mar 10, 2021 at 06:57:34PM +0900, Masami Hiramatsu wrote:
> > If I understand correctly, for #1 you need an unwind hint which treats
> > the instruction *after* the "pushq %rsp" as the beginning of the
> > function.
> 
> Thanks for the patch. In that case, should I still change the stack allocation?
> Or can I continue to use a series of "push/pop" ?

You can continue to use push/pop.  Objtool is only getting confused by
the unbalanced stack of the function (more pushes than pops).  The
unwind hint should fix that.

-- 
Josh


  reply	other threads:[~2021-03-10 15:09 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-05 15:38 [PATCH -tip 0/5] kprobes: Fix stacktrace in kretprobes Masami Hiramatsu
2021-03-05 15:39 ` [PATCH -tip 1/5] ia64: kprobes: Fix to pass correct trampoline address to the handler Masami Hiramatsu
2021-03-05 15:39 ` [PATCH -tip 2/5] kprobes: treewide: Replace arch_deref_entry_point() with dereference_function_descriptor() Masami Hiramatsu
2021-03-05 15:39 ` [PATCH -tip 3/5] kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler() Masami Hiramatsu
2021-03-10 14:21   ` Miroslav Benes
2021-03-10 15:42     ` Masami Hiramatsu
2021-03-11 13:37       ` Masami Hiramatsu
2021-03-05 15:39 ` [PATCH -tip 4/5] kprobes: stacktrace: Recover the address changed by kretprobe Masami Hiramatsu
2021-03-05 15:39 ` [PATCH -tip 5/5] tracing: Remove kretprobe unknown indicator from stacktrace Masami Hiramatsu
2021-03-05 15:44   ` Steven Rostedt
2021-03-05 19:16 ` [PATCH -tip 0/5] kprobes: Fix stacktrace in kretprobes Daniel Xu
2021-03-06  1:13   ` Masami Hiramatsu
2021-03-07 21:23     ` Daniel Xu
2021-03-08  2:52       ` Masami Hiramatsu
2021-03-08 13:05         ` Masami Hiramatsu
2021-03-09  1:19         ` Josh Poimboeuf
2021-03-10  9:57           ` Masami Hiramatsu
2021-03-10 15:08             ` Josh Poimboeuf [this message]
2021-03-10 15:55               ` Masami Hiramatsu
2021-03-10 18:31                 ` Josh Poimboeuf
2021-03-11  0:20                   ` Masami Hiramatsu
2021-03-11  1:06                     ` Josh Poimboeuf
2021-03-11  1:54                       ` Masami Hiramatsu
2021-03-11 16:51                         ` Josh Poimboeuf
2021-03-12  3:22                           ` Masami Hiramatsu
2021-03-10 22:46                 ` Daniel Xu
2021-03-09 21:34         ` Daniel Xu
2021-03-10 10:50           ` Masami Hiramatsu

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