Re: [PATCH v12 6/9] arm64: kdump: reimplement crashkernel=X

From: Catalin Marinas
Date: Mon Oct 05 2020 - 13:16:17 EST


On Mon, Sep 07, 2020 at 09:47:42PM +0800, Chen Zhou wrote:
> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
> index 53acbeca4f57..1b24072f2bae 100644
> --- a/arch/arm64/kernel/setup.c
> +++ b/arch/arm64/kernel/setup.c
> @@ -238,7 +238,18 @@ static void __init request_standard_resources(void)
> kernel_data.end <= res->end)
> request_resource(res, &kernel_data);
> #ifdef CONFIG_KEXEC_CORE
> - /* Userspace will find "Crash kernel" region in /proc/iomem. */
> + /*
> + * Userspace will find "Crash kernel" or "Crash kernel (low)"
> + * region in /proc/iomem.
> + * In order to distinct from the high region and make no effect
> + * to the use of existing kexec-tools, rename the low region as
> + * "Crash kernel (low)".
> + */
> + if (crashk_low_res.end && crashk_low_res.start >= res->start &&
> + crashk_low_res.end <= res->end) {
> + crashk_low_res.name = "Crash kernel (low)";
> + request_resource(res, &crashk_low_res);
> + }

With the changes in this series (including the above), how do the
current kexec-tools behave? Do they pick just the high region and the
loaded kernel will subsequently fail to boot?

--
Catalin