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Piccoli" Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, dyoung@redhat.com, linux-doc@vger.kernel.org, vgoyal@redhat.com, stern@rowland.harvard.edu, akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, corbet@lwn.net, halves@canonical.com, kernel@gpiccoli.net Subject: Re: [PATCH V4] notifier/panic: Introduce panic_notifier_filter Message-ID: <20220116131129.GD2388@MiWiFi-R3L-srv> References: <20220108153451.195121-1-gpiccoli@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220108153451.195121-1-gpiccoli@igalia.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/08/22 at 12:34pm, Guilherme G. Piccoli wrote: ...... > So, this patch aims to ease this decision: we hereby introduce a filter > for the panic notifier list, in which users may select specifically > which callbacks they wish to run, allowing a safer kdump. The allowlist > should be provided using the parameter "panic_notifier_filter=a,b,..." > where a, b are valid callback names. Invalid symbols are discarded. > > Currently up to 16 symbols may be passed in this list, we consider > that this numbers allows enough flexibility (and no matter what > architecture is used, at most 30 panic callbacks are registered). > In an experiment using a qemu x86 virtual machine, by default only > six callbacks are registered in the panic notifier list. > Once a valid callback name is provided in the list, such function > is allowed to be registered/unregistered in the panic_notifier_list; > all other panic callbacks are ignored. Notice that this filter is > only for the panic notifiers and has no effect in the other notifiers. > > Signed-off-by: Guilherme G. Piccoli This patch looks good to me, thx. Acked-by: Baoquan He