Re: [PATCH v14 01/11] x86: kdump: replace the hard-coded alignment with macro CRASH_ALIGN
From: Catalin Marinas <catalin.marinas@arm.com>
Date: 2021-02-24 15:11:29
Also in:
kexec, linux-arm-kernel, lkml
On Sat, Jan 30, 2021 at 03:10:15PM +0800, 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.
[...]
quoted hunk ↗ jump to hunk
@@ -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); if (start != crash_base) { pr_info("crashkernel reservation failed - memory is in use.\n");
There is a small functional change here for x86. Prior to this patch, crash_base passed by the user on the command line is allowed to be 1MB aligned. With this patch, such reservation will fail. Is the current behaviour a bug in the current x86 code or it does allow 1MB-aligned reservations? -- Catalin