Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753644Ab3DPFYR (ORCPT ); Tue, 16 Apr 2013 01:24:17 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:27340 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752861Ab3DPFYK (ORCPT ); Tue, 16 Apr 2013 01:24:10 -0400 From: Yinghai Lu To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: WANG Chao , Vivek Goyal , "Eric W. Biederman" , linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH v6 2/4] x86, kdump: Retore crashkernel= to allocate under 896M Date: Mon, 15 Apr 2013 22:23:47 -0700 Message-Id: <1366089828-19692-4-git-send-email-yinghai@kernel.org> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1366089828-19692-1-git-send-email-yinghai@kernel.org> References: <1366089828-19692-1-git-send-email-yinghai@kernel.org> X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6141 Lines: 155 Vivek found old kexec-tools does not work new kernel anymore. So change back crashkernel= back to old behavoir, and add crashkernel_high= to let user decide if buffer could be above 4G, and also new kexec-tools will be needed. -v2: let crashkernel=X override crashkernel_high= update description about _high will be ignored by crashkernel=X -v3: update description about kernel-parameters.txt according to Vivek. Signed-off-by: Yinghai Lu Acked-by: Vivek Goyal --- Documentation/kernel-parameters.txt | 13 +++++++++++-- arch/x86/kernel/setup.c | 24 +++++++++++++++++++----- include/linux/kexec.h | 2 ++ kernel/kexec.c | 9 +++++++++ 4 files changed, 41 insertions(+), 7 deletions(-) Index: linux-2.6/Documentation/kernel-parameters.txt =================================================================== --- linux-2.6.orig/Documentation/kernel-parameters.txt +++ linux-2.6/Documentation/kernel-parameters.txt @@ -603,9 +603,16 @@ bytes respectively. Such letter suffixes a memory unit (amount[KMG]). See also Documentation/kdump/kdump.txt for an example. + crashkernel_high=size[KMG] + [KNL, x86_64] range could be above 4G. Allow kernel + to allocate physical memory region from top, so could + be above 4G if system have more than 4G ram installed. + Otherwise memory region will be allocated below 4G, if + available. + It will be ignored if crashkernel=X is specified. crashkernel_low=size[KMG] - [KNL, x86_64] range under 4G. When crashkernel= is - passed, kernel allocate physical memory region + [KNL, x86_64] range under 4G. When crashkernel_high= is + passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system that require some amount of low memory, e.g. swiotlb requires at least 64M+32K low memory. Kernel would @@ -613,6 +620,8 @@ bytes respectively. Such letter suffixes This one let user to specify own low range under 4G for second kernel instead. 0: to disable low allocation. + It will be ignored when crashkernel_high=X is not used + or memory reserved is below 4G. cs89x0_dma= [HW,NET] Format: Index: linux-2.6/arch/x86/kernel/setup.c =================================================================== --- linux-2.6.orig/arch/x86/kernel/setup.c +++ linux-2.6/arch/x86/kernel/setup.c @@ -505,11 +505,14 @@ static void __init memblock_x86_reserve_ /* * Keep the crash kernel below this limit. On 32 bits earlier kernels * would limit the kernel to the low 512 MiB due to mapping restrictions. + * On 64bit, old kexec-tools need to under 896MiB. */ #ifdef CONFIG_X86_32 -# define CRASH_KERNEL_ADDR_MAX (512 << 20) +# define CRASH_KERNEL_ADDR_LOW_MAX (512 << 20) +# define CRASH_KERNEL_ADDR_HIGH_MAX (512 << 20) #else -# define CRASH_KERNEL_ADDR_MAX MAXMEM +# define CRASH_KERNEL_ADDR_LOW_MAX (896UL<<20) +# define CRASH_KERNEL_ADDR_HIGH_MAX MAXMEM #endif static void __init reserve_crashkernel_low(void) @@ -523,6 +526,7 @@ static void __init reserve_crashkernel_l int ret; total_low_mem = memblock_mem_size(1UL<<(32-PAGE_SHIFT)); + /* crashkernel_low=YM */ ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base); if (ret != 0) { @@ -567,14 +571,22 @@ static void __init reserve_crashkernel(v const unsigned long long alignment = 16<<20; /* 16M */ unsigned long long total_mem; unsigned long long crash_size, crash_base; + bool high = false; int ret; total_mem = memblock_phys_mem_size(); + /* crashkernel=XM */ ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base); - if (ret != 0 || crash_size <= 0) - return; + if (ret != 0 || crash_size <= 0) { + /* crashkernel_high=XM */ + ret = parse_crashkernel_high(boot_command_line, total_mem, + &crash_size, &crash_base); + if (ret != 0 || crash_size <= 0) + return; + high = true; + } /* 0 means: find the address automatically */ if (crash_base <= 0) { @@ -582,7 +594,9 @@ static void __init reserve_crashkernel(v * kexec want bzImage is below CRASH_KERNEL_ADDR_MAX */ crash_base = memblock_find_in_range(alignment, - CRASH_KERNEL_ADDR_MAX, crash_size, alignment); + high ? CRASH_KERNEL_ADDR_HIGH_MAX : + CRASH_KERNEL_ADDR_LOW_MAX, + crash_size, alignment); if (!crash_base) { pr_info("crashkernel reservation failed - No suitable area found.\n"); Index: linux-2.6/include/linux/kexec.h =================================================================== --- linux-2.6.orig/include/linux/kexec.h +++ linux-2.6/include/linux/kexec.h @@ -200,6 +200,8 @@ extern size_t vmcoreinfo_max_size; int __init parse_crashkernel(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, unsigned long long *crash_base); +int parse_crashkernel_high(char *cmdline, unsigned long long system_ram, + unsigned long long *crash_size, unsigned long long *crash_base); int parse_crashkernel_low(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, unsigned long long *crash_base); int crash_shrink_memory(unsigned long new_size); Index: linux-2.6/kernel/kexec.c =================================================================== --- linux-2.6.orig/kernel/kexec.c +++ linux-2.6/kernel/kexec.c @@ -1422,6 +1422,15 @@ int __init parse_crashkernel(char *cmdli "crashkernel="); } +int __init parse_crashkernel_high(char *cmdline, + unsigned long long system_ram, + unsigned long long *crash_size, + unsigned long long *crash_base) +{ + return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, + "crashkernel_high="); +} + int __init parse_crashkernel_low(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/