Re: [PATCH 1/2 v8] resource: add the new I/O resource descriptor 'IORES_DESC_RESERVED'
From: lijiang
Date: Thu Nov 29 2018 - 23:44:53 EST
å 2018å11æ30æ 11:41, Dave Young åé:
> On 11/29/18 at 04:09pm, Lianbo Jiang wrote:
>> When doing kexec_file_load, the first kernel needs to pass the e820
>> reserved ranges to the second kernel. But kernel can not exactly
>> match the e820 reserved ranges when walking through the iomem resources
>> with the descriptor 'IORES_DESC_NONE', because several e820 types(
>> e.g. E820_TYPE_RESERVED_KERN/E820_TYPE_RAM/E820_TYPE_UNUSABLE/E820
>> _TYPE_RESERVED) are converted to the descriptor 'IORES_DESC_NONE'. It
>> may pass these four types to the kdump kernel, that is not desired result.
>>
>> So, this patch adds a new I/O resource descriptor 'IORES_DESC_RESERVED'
>> for the iomem resources search interfaces. It is helpful to exactly
>> match the reserved resource ranges when walking through iomem resources.
>>
>> In addition, since the new descriptor 'IORES_DESC_RESERVED' is introduced,
>> these code originally related to the descriptor 'IORES_DESC_NONE' need to
>> be updated. Otherwise, it will be easily confused and also cause some
>> errors. Because the 'E820_TYPE_RESERVED' type is converted to the new
>> descriptor 'IORES_DESC_RESERVED' instead of 'IORES_DESC_NONE', it has been
>> changed.
>>
>> Suggested-by: Dave Young <dyoung@xxxxxxxxxx>
>
> This was suggested by Boris instead :)
>
Sorry for this, i forgot to change it.
And i will correct this in next version.
Thanks.
>> Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
>> ---
>> arch/ia64/kernel/efi.c | 4 ++++
>> arch/x86/kernel/e820.c | 2 +-
>> arch/x86/mm/ioremap.c | 13 ++++++++++++-
>> include/linux/ioport.h | 1 +
>> kernel/resource.c | 6 +++---
>> 5 files changed, 21 insertions(+), 5 deletions(-)
>>
>>
> [snip]
>
> Thanks
> Dave
>