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Date:   Wed, 20 Jul 2022 15:43:44 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Josh Poimboeuf <jpoimboe@kernel.org>,
        Andrew Cooper <Andrew.Cooper3@citrix.com>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Johannes Wikner <kwikner@ethz.ch>,
        Alyssa Milburn <alyssa.milburn@linux.intel.com>,
        Jann Horn <jannh@google.com>, "H.J. Lu" <hjl.tools@gmail.com>,
        Joao Moreira <joao.moreira@intel.com>,
        Joseph Nuzman <joseph.nuzman@intel.com>,
        Juergen Gross <jgross@suse.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [patch 00/38] x86/retbleed: Call depth tracking mitigation
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On Wed, 20 Jul 2022 12:36:38 -0700
Kees Cook <keescook@chromium.org> wrote:

> I'd rather not remove it (or do it dynamically) since the point is to
> test what has been generated by the toolchain/build process and stuffed
> into the .rodata section. i.e. making sure gadgets there can't be
> executed, that the boot-time section permission-setting works correctly,
> etc. Before the retbleed mitigation, this test worked for all
> architectures; I'd hate to regress it. :(

If you haven't noticed my reply, I wasn't able to come up with a one line
workaround, but I was able to come up with a two line workaround. Hopefully
that will be good enough to keep your little feature.

  https://lore.kernel.org/all/20220720151123.0e5bf61e@gandalf.local.home/

I'm currently running it under my entire ftrace test suite. If it passes,
I'll submit a formal patch.

-- Steve