Re: [PATCH v14 01/11] x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN

[Baoquan He <bhe@redhat.com>]

On 01/30/21 at 03:10pm, Chen Zhou wrote:
> Move CRASH_ALIGN to header asm/kexec.h for later use. Besides, the
> alignment of crash kernel regions in x86 is 16M(CRASH_ALIGN), but
> function reserve_crashkernel() also used 1M alignment. So just
> replace hard-coded alignment 1M with macro CRASH_ALIGN.
> 
> Suggested-by: Dave Young <dyoung@redhat.com>
> Suggested-by: Baoquan He <bhe@redhat.com>
> Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
> Tested-by: John Donnelly <John.p.donnelly@oracle.com>
> ---
>  arch/x86/include/asm/kexec.h | 3 +++
>  arch/x86/kernel/setup.c      | 5 +----
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
> index 6802c59e8252..be18dc7ae51f 100644
> --- a/arch/x86/include/asm/kexec.h
> +++ b/arch/x86/include/asm/kexec.h
> @@ -18,6 +18,9 @@
>  
>  # define KEXEC_CONTROL_CODE_MAX_SIZE	2048
>  
> +/* 16M alignment for crash kernel regions */
> +#define CRASH_ALIGN		SZ_16M
> +
>  #ifndef __ASSEMBLY__
>  
>  #include <linux/string.h>
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 3412c4595efd..da769845597d 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -390,9 +390,6 @@ static void __init memblock_x86_reserve_range_setup_data(void)
>  
>  #ifdef CONFIG_KEXEC_CORE
>  
> -/* 16M alignment for crash kernel regions */
> -#define CRASH_ALIGN		SZ_16M
> -
>  /*
>   * Keep the crash kernel below this limit.
>   *
> @@ -510,7 +507,7 @@ static void __init reserve_crashkernel(void)
>  	} else {
>  		unsigned long long start;
>  
> -		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
> +		start = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base,
>  						  crash_base + crash_size);

Looks good to me, thx.

Acked-by: Baoquan He <bhe@redhat.com>

>  		if (start != crash_base) {
>  			pr_info("crashkernel reservation failed - memory is in use.\n");
> -- 
> 2.20.1
>