Implement "crashkernel=auto" for x86 first, other arch will be added in the following patches. Signed-off-by: WANG Cong <amwang@xxxxxxxxxx> --- Index: linux-2.6/kernel/kexec.c =================================================================== --- linux-2.6.orig/kernel/kexec.c +++ linux-2.6/kernel/kexec.c @@ -37,6 +37,7 @@ #include <asm/io.h> #include <asm/system.h> #include <asm/sections.h> +#include <asm/setup.h> /* Per cpu memory for storing cpu states in case of system crash. */ note_buf_t* crash_notes; @@ -1297,6 +1298,38 @@ int __init parse_crashkernel(char *cm ck_cmdline += 12; /* strlen("crashkernel=") */ +#ifdef CONFIG_KEXEC_AUTO_RESERVE + if (strncmp(ck_cmdline, "auto", 4) == 0) { + unsigned long long size; + char tmp[32]; + + size = arch_default_crash_size(system_ram); + if (size != 0) { + *crash_size = size; + *crash_base = arch_default_crash_base(); + size = scnprintf(tmp, sizeof(tmp), "%luM@%luM", + (unsigned long)(*crash_size)>>20, + (unsigned long)(*crash_base)>>20); + /* size can't be <= 4. */ + if (likely((size - 4 + strlen(cmdline)) + < COMMAND_LINE_SIZE - 1)) { + memmove(ck_cmdline + size, ck_cmdline + 4, + strlen(cmdline) - (ck_cmdline + 4 - cmdline) + 1); + memcpy(ck_cmdline, tmp, size); + } + return 0; + } else { + /* + * We can't reserve memory auotmatcally, + * remove "crashkernel=" from cmdline. + */ + ck_cmdline += 4; /* strlen("auto") */ + memmove(ck_cmdline - 16, ck_cmdline, + strlen(cmdline) - (ck_cmdline - cmdline) + 1); + return -ENOMEM; + } + } +#endif /* * if the commandline contains a ':', then that's the extended * syntax -- if not, it must be the classic syntax Index: linux-2.6/arch/x86/include/asm/kexec.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/kexec.h +++ linux-2.6/arch/x86/include/asm/kexec.h @@ -61,6 +61,29 @@ # define KEXEC_ARCH KEXEC_ARCH_X86_64 #endif +#ifdef CONFIG_KEXEC_AUTO_RESERVE +#ifndef KEXEC_AUTO_RESERVED_SIZE +#define KEXEC_AUTO_RESERVED_SIZE 1ULL<<27 /* 128M */ +#endif +#ifndef KEXEC_AUTO_THRESHOLD +#define KEXEC_AUTO_THRESHOLD 1ULL<<32 /* 4G */ +#endif +static inline +unsigned long long arch_default_crash_size(unsigned long long total_size) +{ + if (total_size < KEXEC_AUTO_THRESHOLD) + return 0; + else + return KEXEC_AUTO_RESERVED_SIZE; +} +static inline +unsigned long long arch_default_crash_base(void) +{ + /* On x86, 0 means find the base address automatically. */ + return 0; +} +#endif + /* * CPU does not save ss and sp on stack if execution is already * running in kernel mode at the time of NMI occurrence. This code -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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