Re: [PATCH v12 3/9] x86: kdump: use macro CRASH_ADDR_LOW_MAX in functions reserve_crashkernel[_low]()
From: Dave Young <hidden>
Date: 2020-09-18 03:01:58
Also in:
kexec, linux-arm-kernel, lkml
On 09/07/20 at 09:47pm, Chen Zhou wrote:
quoted hunk ↗ jump to hunk
To make the functions reserve_crashkernel[_low]() as generic, replace some hard-coded numbers with macro CRASH_ADDR_LOW_MAX. Signed-off-by: Chen Zhou <redacted> --- arch/x86/kernel/setup.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index d7fd90c52dae..71a6a6e7ca5b 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c@@ -430,7 +430,7 @@ static int __init reserve_crashkernel_low(void) unsigned long total_low_mem; int ret; - total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT)); + total_low_mem = memblock_mem_size(CRASH_ADDR_LOW_MAX >> PAGE_SHIFT);
total_low_mem != CRASH_ADDR_LOW_MAX
/* crashkernel=Y,low */ ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base);
The param total_low_mem is for dynamically change crash_size according to system ram size. Is above change a must for your arm64 patches?
quoted hunk ↗ jump to hunk
@@ -451,7 +451,7 @@ static int __init reserve_crashkernel_low(void) return 0; } - low_base = memblock_find_in_range(CRASH_ALIGN, 1ULL << 32, low_size, CRASH_ALIGN); + low_base = memblock_find_in_range(CRASH_ALIGN, CRASH_ADDR_LOW_MAX, low_size, CRASH_ALIGN); if (!low_base) { pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", (unsigned long)(low_size >> 20));@@ -504,8 +504,9 @@ static void __init reserve_crashkernel(void) if (!crash_base) { /* * Set CRASH_ADDR_LOW_MAX upper bound for crash memory, - * crashkernel=x,high reserves memory over 4G, also allocates - * 256M extra low memory for DMA buffers and swiotlb. + * crashkernel=x,high reserves memory over CRASH_ADDR_LOW_MAX, + * also allocates 256M extra low memory for DMA buffers + * and swiotlb. * But the extra memory is not required for all machines. * So try low memory first and fall back to high memory * unless "crashkernel=size[KMG],high" is specified.@@ -539,7 +540,7 @@ static void __init reserve_crashkernel(void) return; } - if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { + if (crash_base >= CRASH_ADDR_LOW_MAX && reserve_crashkernel_low()) { memblock_free(crash_base, crash_size); return; }-- 2.20.1