Re: [PATCH v12 7/7] x86/crash: Add x86 crash hotplug support

From: Borislav Petkov
Date: Fri Oct 28 2022 - 16:30:56 EST


On Fri, Oct 28, 2022 at 02:26:58PM -0500, Eric DeVolder wrote:
> config CRASH_MAX_MEMORY_RANGES
> depends on CRASH_DUMP && KEXEC_FILE && MEMORY_HOTPLUG
> int
> default 8192
> help
> For the kexec_file_load path, specify the maximum number of
> memory regions, eg. as represented by the 'System RAM' entries
> in /proc/iomem, that the elfcorehdr buffer/segment can accommodate.
> This value is combined with NR_CPUS and multiplied by Elf64_Phdr
> size to determine the final buffer size.

No, do this:

config CRASH_MEMORY_HOTPLUG_SUPPORT
depends on CRASH_DUMP && KEXEC_FILE && MEMORY_HOTPLUG
help
Help text explaining what this feature is

this thing will simply get enabled when the user enables MEMORY_HOTPLUG
and CRASH_DUMP.

and then you do in the code:

/*
* A comment explaining how the 8192 value has been selected.
*/
#define CRASH_MAX_MEMORY_RANGES 8192

Thx.

--
Regards/Gruss,
Boris.

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