From: Peter Zijlstra <peterz@infradead.org>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
Ingo Molnar <mingo@kernel.org>,
Suleiman Souhlal <suleiman@google.com>, bpf <bpf@vger.kernel.org>,
linux-kernel@vger.kernel.org, Borislav Petkov <bp@suse.de>,
Josh Poimboeuf <jpoimboe@kernel.org>,
x86@kernel.org
Subject: Re: [PATCH 1/2] x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK
Date: Wed, 7 Sep 2022 16:28:28 +0200 [thread overview]
Message-ID: <YxiqjKU9xGma3Bnt@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20220907224913.dfdbea2ec6cd637438dbd09a@kernel.org>
On Wed, Sep 07, 2022 at 10:49:13PM +0900, Masami Hiramatsu wrote:
> On Wed, 7 Sep 2022 14:56:52 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
>
> > On Wed, Sep 07, 2022 at 09:55:21AM +0900, Masami Hiramatsu (Google) wrote:
> >
> > > if (!kallsyms_lookup_size_offset(paddr, NULL, &offset))
> > > return 0;
> > >
> >
> > One more thing:
> >
> > https://lkml.kernel.org/r/20220902130951.853460809@infradead.org
> >
> > can result in negative offsets. The expression:
> >
> > 'paddr - offset'
> >
> > will still get you to +0, but I might not have fully considered things
> > when I wrote that patch.
>
> Hmm, isn't 'offset' unsigned? If 'paddr - offset' is still available
> to find the function entry address, it is OK to me.
Yeah, but the magic of 2s complement means it doesn't matter ;-)
next prev parent reply other threads:[~2022-09-07 14:29 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-07 0:55 [PATCH 0/2] x86/kprobes: Fixes for CONFIG_RETHUNK Masami Hiramatsu (Google)
2022-09-07 0:55 ` [PATCH 1/2] x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK Masami Hiramatsu (Google)
2022-09-07 7:06 ` Peter Zijlstra
2022-09-07 9:01 ` [PATCH] objtool,x86: Teach decode about LOOP* instructions Peter Zijlstra
2022-09-07 9:06 ` David Laight
2022-09-07 9:40 ` Peter Zijlstra
2022-09-07 11:13 ` David Laight
2022-09-15 14:24 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2022-09-07 9:12 ` [PATCH 1/2] x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK Masami Hiramatsu
2022-09-07 9:38 ` Peter Zijlstra
2022-09-07 9:53 ` Masami Hiramatsu
2022-09-07 8:02 ` Peter Zijlstra
2022-09-07 8:11 ` Peter Zijlstra
2022-09-07 9:49 ` Masami Hiramatsu
2022-09-07 10:19 ` Peter Zijlstra
2022-09-07 11:44 ` Peter Zijlstra
2022-09-07 13:05 ` Peter Zijlstra
2022-09-07 14:14 ` Masami Hiramatsu
2022-09-07 14:27 ` Peter Zijlstra
2022-09-07 15:22 ` Masami Hiramatsu
2022-09-07 12:56 ` Peter Zijlstra
2022-09-07 13:49 ` Masami Hiramatsu
2022-09-07 14:28 ` Peter Zijlstra [this message]
2022-09-07 12:59 ` Peter Zijlstra
2022-09-07 13:53 ` Masami Hiramatsu
2022-09-07 0:55 ` [PATCH 2/2] x86/kprobes: Fix optprobe optimization " Masami Hiramatsu (Google)
2022-09-07 6:52 ` [PATCH 0/2] x86/kprobes: Fixes for CONFIG_RETHUNK Peter Zijlstra
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=YxiqjKU9xGma3Bnt@hirez.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=bp@suse.de \
--cc=bpf@vger.kernel.org \
--cc=jpoimboe@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@kernel.org \
--cc=rostedt@goodmis.org \
--cc=suleiman@google.com \
--cc=x86@kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).