Re: [PATCH v11 5/5] kdump: update Documentation about crashkernel

From: Catalin Marinas
Date: Wed Sep 02 2020 - 12:43:03 EST


On Tue, Aug 18, 2020 at 03:07:04PM +0800, chenzhou wrote:
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index a8e34d97a894..4df18c7ea438 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -147,7 +147,7 @@ static void __init reserve_crashkernel(void)
> }
> memblock_reserve(crash_base, crash_size);
>
> - if (crash_base >= CRASH_ADDR_LOW_MAX) {
> + if (memstart_addr < CRASH_ADDR_LOW_MAX && crash_base >= CRASH_ADDR_LOW_MAX) {
> const char *rename = "Crash kernel (low)";

Since CRASH_ADDR_LOW_MAX is defined as arm64_dma32_phys_limit and such
limit is always greater than memstart_addr, this additional check
doesn't do anything. See my other reply on how ZONE_DMA32 is created on
arm64.

--
Catalin