Re: [PATCH v13 1/8] x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN

From: Mike Rapoport
Date: Thu Nov 12 2020 - 02:58:28 EST


Hi,

On Sat, Oct 31, 2020 at 03:44:30PM +0800, Chen Zhou wrote:
> Move CRASH_ALIGN to header asm/kexec.h and replace the hard-coded
> alignment with macro CRASH_ALIGN in function reserve_crashkernel().
>
> Suggested-by: Dave Young <dyoung@xxxxxxxxxx>
> Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx>
> Tested-by: John Donnelly <John.p.donnelly@xxxxxxxxxx>
> ---
> 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..8cf9d3fd31c7 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
>
> +/* 2M alignment for crash kernel regions */
> +#define CRASH_ALIGN SZ_16M

Please update the comment to match the code.

> +
> #ifndef __ASSEMBLY__
>
> #include <linux/string.h>
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 84f581c91db4..bf373422dc8a 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -395,9 +395,6 @@ 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.
> *
> @@ -515,7 +512,7 @@ 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);
> if (start != crash_base) {
> pr_info("crashkernel reservation failed - memory is in use.\n");
> --
> 2.20.1
>

--
Sincerely yours,
Mike.