All of lore.kernel.org
 help / color / mirror / Atom feed
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@kernel.org>, X86 ML <x86@kernel.org>,
	Daniel Xu <dxu@dxuuu.xyz>,
	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,
	linux-ia64@vger.kernel.org
Subject: Re: [PATCH -tip v3 05/11] x86/kprobes: Add UNWIND_HINT_FUNC on kretprobe_trampoline code
Date: Sun, 21 Mar 2021 12:50:04 -0500	[thread overview]
Message-ID: <20210321174855.oqqtvgb2xwyk4klf@treble> (raw)
In-Reply-To: <20210320211616.a976fc66d0c51e13d3121e2f@kernel.org>

On Sat, Mar 20, 2021 at 09:16:16PM +0900, Masami Hiramatsu wrote:
> On Fri, 19 Mar 2021 21:22:39 +0900
> Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 
> > From: Josh Poimboeuf <jpoimboe@redhat.com>
> > 
> > Add UNWIND_HINT_FUNC on kretporbe_trampoline code so that ORC
> > information is generated on the kretprobe_trampoline correctly.
> > 
> 
> Test bot also found a new warning for this.
> 
> > >> arch/x86/kernel/kprobes/core.o: warning: objtool: kretprobe_trampoline()+0x25: call without frame pointer save/setup
> 
> With CONFIG_FRAME_POINTER=y.
> 
> Of course this can be fixed with additional "push %bp; mov %sp, %bp" before calling
> trampoline_handler. But actually we know that this function has a bit special
> stack frame too. 
> 
> Can I recover STACK_FRAME_NON_STANDARD(kretprobe_trampoline) when CONFIG_FRAME_POINTER=y ?

Yes, that's what I'd recommend.

-- 
Josh


WARNING: multiple messages have this Message-ID (diff)
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@kernel.org>, X86 ML <x86@kernel.org>,
	Daniel Xu <dxu@dxuuu.xyz>,
	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,
	linux-ia64@vger.kernel.org
Subject: Re: [PATCH -tip v3 05/11] x86/kprobes: Add UNWIND_HINT_FUNC on kretprobe_trampoline code
Date: Sun, 21 Mar 2021 17:50:04 +0000	[thread overview]
Message-ID: <20210321174855.oqqtvgb2xwyk4klf@treble> (raw)
In-Reply-To: <20210320211616.a976fc66d0c51e13d3121e2f@kernel.org>

On Sat, Mar 20, 2021 at 09:16:16PM +0900, Masami Hiramatsu wrote:
> On Fri, 19 Mar 2021 21:22:39 +0900
> Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 
> > From: Josh Poimboeuf <jpoimboe@redhat.com>
> > 
> > Add UNWIND_HINT_FUNC on kretporbe_trampoline code so that ORC
> > information is generated on the kretprobe_trampoline correctly.
> > 
> 
> Test bot also found a new warning for this.
> 
> > >> arch/x86/kernel/kprobes/core.o: warning: objtool: kretprobe_trampoline()+0x25: call without frame pointer save/setup
> 
> With CONFIG_FRAME_POINTER=y.
> 
> Of course this can be fixed with additional "push %bp; mov %sp, %bp" before calling
> trampoline_handler. But actually we know that this function has a bit special
> stack frame too. 
> 
> Can I recover STACK_FRAME_NON_STANDARD(kretprobe_trampoline) when CONFIG_FRAME_POINTER=y ?

Yes, that's what I'd recommend.

-- 
Josh

  parent reply	other threads:[~2021-03-21 17:51 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-19 12:21 [PATCH -tip v3 00/11] kprobes: Fix stacktrace with kretprobes on x86 Masami Hiramatsu
2021-03-19 12:21 ` Masami Hiramatsu
2021-03-19 12:21 ` [PATCH -tip v3 01/11] ia64: kprobes: Fix to pass correct trampoline address to the handler Masami Hiramatsu
2021-03-19 12:21   ` Masami Hiramatsu
2021-03-19 12:22 ` [PATCH -tip v3 02/11] kprobes: treewide: Replace arch_deref_entry_point() with dereference_function_descriptor() Masami Hiramatsu
2021-03-19 12:22   ` [PATCH -tip v3 02/11] kprobes: treewide: Replace arch_deref_entry_point() with dereference_function_ Masami Hiramatsu
2021-03-19 12:22 ` [PATCH -tip v3 03/11] kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler() Masami Hiramatsu
2021-03-19 12:22   ` [PATCH -tip v3 03/11] kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler Masami Hiramatsu
2021-03-19 12:22 ` [PATCH -tip v3 04/11] kprobes: Add kretprobe_find_ret_addr() for searching return address Masami Hiramatsu
2021-03-19 12:22   ` Masami Hiramatsu
2021-03-19 12:22 ` [PATCH -tip v3 05/11] x86/kprobes: Add UNWIND_HINT_FUNC on kretprobe_trampoline code Masami Hiramatsu
2021-03-19 12:22   ` Masami Hiramatsu
2021-03-20 12:16   ` Masami Hiramatsu
2021-03-20 12:16     ` Masami Hiramatsu
2021-03-20 13:05     ` Masami Hiramatsu
2021-03-20 13:05       ` Masami Hiramatsu
2021-03-21 17:52       ` Josh Poimboeuf
2021-03-21 17:52         ` Josh Poimboeuf
2021-03-22  0:08         ` Masami Hiramatsu
2021-03-22  0:08           ` Masami Hiramatsu
2021-03-21 17:50     ` Josh Poimboeuf [this message]
2021-03-21 17:50       ` Josh Poimboeuf
2021-03-19 12:22 ` [PATCH -tip v3 06/11] ARC: Add instruction_pointer_set() API Masami Hiramatsu
2021-03-19 12:22   ` Masami Hiramatsu
2021-03-19 12:23 ` [PATCH -tip v3 07/11] ia64: " Masami Hiramatsu
2021-03-19 12:23   ` Masami Hiramatsu
2021-03-20  1:04   ` Masami Hiramatsu
2021-03-20  1:04     ` Masami Hiramatsu
2021-03-19 12:23 ` [PATCH -tip v3 08/11] kprobes: Setup instruction pointer in __kretprobe_trampoline_handler Masami Hiramatsu
2021-03-19 12:23   ` Masami Hiramatsu
2021-03-21 12:54   ` Masami Hiramatsu
2021-03-21 12:54     ` Masami Hiramatsu
2021-03-19 12:23 ` [PATCH -tip v3 09/11] x86/kprobes: Push a fake return address at kretprobe_trampoline Masami Hiramatsu
2021-03-19 12:23   ` Masami Hiramatsu
2021-03-19 12:23 ` [PATCH -tip v3 10/11] x86/unwind: Recover kretprobe trampoline entry Masami Hiramatsu
2021-03-19 12:23   ` Masami Hiramatsu
2021-03-19 12:23 ` [PATCH -tip v3 11/11] tracing: Show kretprobe unknown indicator only for kretprobe_trampoline Masami Hiramatsu
2021-03-19 12:23   ` Masami Hiramatsu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210321174855.oqqtvgb2xwyk4klf@treble \
    --to=jpoimboe@redhat.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=dxu@dxuuu.xyz \
    --cc=kernel-team@fb.com \
    --cc=kuba@kernel.org \
    --cc=linux-ia64@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mhiramat@kernel.org \
    --cc=mingo@kernel.org \
    --cc=mingo@redhat.com \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.