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Date:   Fri, 6 Nov 2020 11:07:24 +0100 (CET)
From:   Miroslav Benes <mbenes@suse.cz>
To:     Steven Rostedt <rostedt@goodmis.org>
cc:     linux-kernel@vger.kernel.org,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Jiri Kosina <jikos@kernel.org>, Petr Mladek <pmladek@suse.com>,
        Joe Lawrence <joe.lawrence@redhat.com>,
        live-patching@vger.kernel.org
Subject: Re: [PATCH 07/11 v3] livepatch: Trigger WARNING if livepatch function
 fails due to recursion
In-Reply-To: <20201106023547.312639435@goodmis.org>
Message-ID: <alpine.LSU.2.21.2011061106090.10425@pobox.suse.cz>
References: <20201106023235.367190737@goodmis.org> <20201106023547.312639435@goodmis.org>
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On Thu, 5 Nov 2020, Steven Rostedt wrote:

> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
> 
> If for some reason a function is called that triggers the recursion
> detection of live patching, trigger a warning. By not executing the live
> patch code, it is possible that the old unpatched function will be called
> placing the system into an unknown state.
> 
> Link: https://lore.kernel.org/r/20201029145709.GD16774@alley
> 
> Cc: Josh Poimboeuf <jpoimboe@redhat.com>
> Cc: Jiri Kosina <jikos@kernel.org>
> Cc: Joe Lawrence <joe.lawrence@redhat.com>
> Cc: live-patching@vger.kernel.org
> Suggested-by: Miroslav Benes <mbenes@suse.cz>
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Acked-by: Miroslav Benes <mbenes@suse.cz>

> ---
> Changes since v2:
> 
>  - Blame Miroslav instead of Petr ;-)

Thanks. Fortunately, if printk is broken in WARN_ON_ONCE(), I can always 
blame Petr again :)

M