diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 42 | ||||
| -rw-r--r-- | include/linux/kexec.h | 3 | ||||
| -rw-r--r-- | kernel/kexec.c | 34 |
4 files changed, 75 insertions, 7 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 363e348..da0e077 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -594,6 +594,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. is selected automatically. Check Documentation/kdump/kdump.txt for further details. + crashkernel_low=size[KMG] + [KNL, x86] parts under 4G. + crashkernel=range1:size1[,range2:size2,...][@offset] [KNL] Same as above, but depends on the memory in the running system. The syntax of range is diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 4778dde..5dc47c3 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -508,8 +508,44 @@ static void __init memblock_x86_reserve_range_setup_data(void) # define CRASH_KERNEL_ADDR_MAX MAXMEM #endif +static void __init reserve_crashkernel_low(void) +{ +#ifdef CONFIG_X86_64 + const unsigned long long alignment = 16<<20; /* 16M */ + unsigned long long low_base = 0, low_size = 0; + unsigned long total_low_mem; + unsigned long long base; + int ret; + + total_low_mem = memblock_mem_size(1UL<<(32-PAGE_SHIFT)); + ret = parse_crashkernel_low(boot_command_line, total_low_mem, + &low_size, &base); + if (ret != 0 || low_size <= 0) + return; + + low_base = memblock_find_in_range(low_size, (1ULL<<32), + low_size, alignment); + + if (!low_base) { + pr_info("crashkernel low reservation failed - No suitable area found.\n"); + + return; + } + + memblock_reserve(low_base, low_size); + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n", + (unsigned long)(low_size >> 20), + (unsigned long)(low_base >> 20), + (unsigned long)(total_low_mem >> 20)); + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; + insert_resource(&iomem_resource, &crashk_low_res); +#endif +} + static void __init reserve_crashkernel(void) { + const unsigned long long alignment = 16<<20; /* 16M */ unsigned long long total_mem; unsigned long long crash_size, crash_base; int ret; @@ -523,8 +559,6 @@ static void __init reserve_crashkernel(void) /* 0 means: find the address automatically */ if (crash_base <= 0) { - const unsigned long long alignment = 16<<20; /* 16M */ - /* * kexec want bzImage is below CRASH_KERNEL_ADDR_MAX */ @@ -535,6 +569,7 @@ static void __init reserve_crashkernel(void) pr_info("crashkernel reservation failed - No suitable area found.\n"); return; } + } else { unsigned long long start; @@ -556,6 +591,9 @@ static void __init reserve_crashkernel(void) crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; insert_resource(&iomem_resource, &crashk_res); + + if (crash_base >= (1ULL<<32)) + reserve_crashkernel_low(); } #else static void __init reserve_crashkernel(void) diff --git a/include/linux/kexec.h b/include/linux/kexec.h index d0b8458..d2e6927 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -191,6 +191,7 @@ extern struct kimage *kexec_crash_image; /* Location of a reserved region to hold the crash kernel. */ extern struct resource crashk_res; +extern struct resource crashk_low_res; typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4]; extern note_buf_t __percpu *crash_notes; extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; @@ -199,6 +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_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); size_t crash_get_memory_size(void); void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); diff --git a/kernel/kexec.c b/kernel/kexec.c index 5e4bd78..2436ffc 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -54,6 +54,12 @@ struct resource crashk_res = { .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_MEM }; +struct resource crashk_low_res = { + .name = "Crash kernel low", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_MEM +}; int kexec_should_crash(struct task_struct *p) { @@ -1369,10 +1375,11 @@ static int __init parse_crashkernel_simple(char *cmdline, * That function is the entry point for command line parsing and should be * called from the arch-specific code. */ -int __init parse_crashkernel(char *cmdline, +static int __init __parse_crashkernel(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, - unsigned long long *crash_base) + unsigned long long *crash_base, + const char *name) { char *p = cmdline, *ck_cmdline = NULL; char *first_colon, *first_space; @@ -1382,16 +1389,16 @@ int __init parse_crashkernel(char *cmdline, *crash_base = 0; /* find crashkernel and use the last one if there are more */ - p = strstr(p, "crashkernel="); + p = strstr(p, name); while (p) { ck_cmdline = p; - p = strstr(p+1, "crashkernel="); + p = strstr(p+1, name); } if (!ck_cmdline) return -EINVAL; - ck_cmdline += 12; /* strlen("crashkernel=") */ + ck_cmdline += strlen(name); /* * if the commandline contains a ':', then that's the extended @@ -1409,6 +1416,23 @@ int __init parse_crashkernel(char *cmdline, return 0; } +int __init parse_crashkernel(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="); +} + +int __init parse_crashkernel_low(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_low="); +} static void update_vmcoreinfo_note(void) { |
