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Subject: Re: [PATCH 1/1] kernel/crash_core.c - Add crashkernel=auto for x86
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To:     Dave Young <dyoung@redhat.com>,
        Guilherme Piccoli <gpiccoli@canonical.com>
Cc:     Kairui Song <kasong@redhat.com>,
        Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        linux-doc@vger.kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Will Deacon <will@kernel.org>,
        Anson Huang <Anson.Huang@nxp.com>,
        Jonathan Corbet <corbet@lwn.net>,
        the arch/x86 maintainers <x86@kernel.org>,
        Michael Walle <michael@walle.cc>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Vivek Goyal <vgoyal@redhat.com>, Arnd Bergmann <arnd@arndb.de>,
        Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-arm-kernel@lists.infradead.org, Baoquan He <bhe@redhat.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        kexec mailing list <kexec@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "# v4 . 16+" <stable@vger.kernel.org>,
        Li Yang <leoyang.li@nxp.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Vinod Koul <vkoul@kernel.org>,
        =?UTF-8?Q?Diego_Elio_Petten=c3=b2?= <flameeyes@flameeyes.com>,
        Olof Johansson <olof@lixom.net>,
        Shawn Guo <shawnguo@kernel.org>,
        John Donnelly <john.p.donnelly@oracle.com>
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From:   john.p.donnelly@oracle.com
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On 11/22/20 9:47 PM, Dave Young wrote:
> Hi Guilherme,
> On 11/22/20 at 12:32pm, Guilherme Piccoli wrote:
>> Hi Dave and Kairui, thanks for your responses! OK, if that makes sense
>> to you I'm fine with it. I'd just recommend to test recent kernels in
>> multiple distros with the minimum "range" to see if 64M is enough for
>> crashkernel, maybe we'd need to bump that.
> 
> Giving the different kernel configs and the different userspace
> initramfs setup it is hard to get an uniform value for all distributions,
> but we can have an interface/kconfig-option for them to provide a value like this patch
> is doing. And it could be improved like Kairui said about some known
> kernel added extra values later, probably some more improvements if
> doable.
> 
> Thanks
> Dave
> 

Hi.

Are we going to move forward with implementing this for X86 and Arm ?

If other platform maintainers want to include this CONFIG option in 
their configuration settings they have a starting point.

Thank you,

John.

( I am not currently on many of the included dist lists  in this email, 
so hopefully key contributors are included in this exchange )