From e25e6e7593cae350ecaa3fcd6d20c7de87f4c309 Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yinghai@kernel.org>
Date: Fri, 22 Mar 2013 13:54:06 -0700
Subject: [PATCH] kdump, x86: Process multiple Crash kernel in /proc/iomem
Vivek found specical handling crashkernel low in not good.
We should extend kexec-tools to handle multiple Crash kernel instead.
Extend crash_reserved_mem to array instead and use
kexec_iomem_for_each_line directly. After that we can drop
crashkernel low.
-v2: fix left over calling of parse_iomem_single() found by Vivek.
Suggested-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
kexec/arch/i386/crashdump-x86.c | 107 +++++++++++++++++++++----------------
kexec/arch/i386/kexec-x86-common.c | 4 +-
kexec/kexec.h | 1 +
3 files changed, 65 insertions(+), 47 deletions(-)
diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c
index 9ab648b..4167e5e 100644
--- a/kexec/arch/i386/crashdump-x86.c
+++ b/kexec/arch/i386/crashdump-x86.c
@@ -188,9 +188,9 @@ static int exclude_region(int *nr_ranges, uint64_t start, uint64_t end);
static struct memory_range crash_memory_range[CRASH_MAX_MEMORY_RANGES];
/* Memory region reserved for storing panic kernel and other data. */
-static struct memory_range crash_reserved_mem;
-/* under 4G parts */
-static struct memory_range crash_reserved_low_mem;
+#define CRASH_RESERVED_MEM_NR 8
+static struct memory_range crash_reserved_mem[CRASH_RESERVED_MEM_NR];
+static int crash_reserved_mem_nr;
/* Reads the appropriate file and retrieves the SYSTEM RAM regions for whom to
* create Elf headers. Keeping it separate from get_memory_ranges() as
@@ -207,7 +207,7 @@ static int get_crash_memory_ranges(struct memory_range **range, int *ranges,
int kexec_flags, unsigned long lowmem_limit)
{
const char *iomem = proc_iomem();
- int memory_ranges = 0, gart = 0;
+ int memory_ranges = 0, gart = 0, i;
char line[MAX_LINE];
FILE *fp;
unsigned long long start, end;
@@ -268,29 +268,28 @@ static int get_crash_memory_ranges(struct memory_range **range, int *ranges,
}
fclose(fp);
if (kexec_flags & KEXEC_PRESERVE_CONTEXT) {
- int i;
for (i = 0; i < memory_ranges; i++) {
if (crash_memory_range[i].end > 0x0009ffff) {
- crash_reserved_mem.start = \
+ crash_reserved_mem[0].start = \
crash_memory_range[i].start;
break;
}
}
- if (crash_reserved_mem.start >= mem_max) {
+ if (crash_reserved_mem[0].start >= mem_max) {
fprintf(stderr, "Too small mem_max: 0x%llx.\n",
mem_max);
return -1;
}
- crash_reserved_mem.end = mem_max;
- crash_reserved_mem.type = RANGE_RAM;
+ crash_reserved_mem[0].end = mem_max;
+ crash_reserved_mem[0].type = RANGE_RAM;
+ crash_reserved_mem_nr = 1;
}
- if (exclude_region(&memory_ranges, crash_reserved_mem.start,
- crash_reserved_mem.end) < 0)
- return -1;
- if (crash_reserved_low_mem.start &&
- exclude_region(&memory_ranges, crash_reserved_low_mem.start,
- crash_reserved_low_mem.end) < 0)
- return -1;
+
+ for (i = 0; i < crash_reserved_mem_nr; i++)
+ if (exclude_region(&memory_ranges, crash_reserved_mem[i].start,
+ crash_reserved_mem[i].end) < 0)
+ return -1;
+
if (gart) {
/* exclude GART region if the system has one */
if (exclude_region(&memory_ranges, gart_start, gart_end) < 0)
@@ -351,9 +350,10 @@ static int get_crash_memory_ranges_xen(struct memory_range **range,
qsort(*range, *ranges, sizeof(struct memory_range), compare_ranges);
- if (exclude_region(ranges, crash_reserved_mem.start,
- crash_reserved_mem.end) < 0)
- goto err;
+ for (i = 0; i < crash_reserved_mem_nr; i++)
+ if (exclude_region(ranges, crash_reserved_mem[i].start,
+ crash_reserved_mem[i].end) < 0)
+ goto err;
ret = 0;
@@ -434,9 +434,10 @@ static int get_crash_memory_ranges_xen(struct memory_range **range,
qsort(*range, *ranges, sizeof(struct memory_range), compare_ranges);
- if (exclude_region(ranges, crash_reserved_mem.start,
- crash_reserved_mem.end) < 0)
- goto err;
+ for (i = 0; i < crash_reserved_mem_nr; i++)
+ if (exclude_region(ranges, crash_reserved_mem[i].start,
+ crash_reserved_mem[i].end) < 0)
+ goto err;
ret = 0;
@@ -1014,15 +1015,10 @@ int load_crashdump_segments(struct kexec_info *info, char* mod_cmdline,
memmap_p = xmalloc(sz);
memset(memmap_p, 0, sz);
add_memmap(memmap_p, info->backup_src_start, info->backup_src_size);
- sz = crash_reserved_mem.end - crash_reserved_mem.start +1;
- if (add_memmap(memmap_p, crash_reserved_mem.start, sz) < 0) {
- return ENOCRASHKERNEL;
- }
-
- if (crash_reserved_low_mem.start) {
- sz = crash_reserved_low_mem.end - crash_reserved_low_mem.start
- +1;
- add_memmap(memmap_p, crash_reserved_low_mem.start, sz);
+ for (i = 0; i < crash_reserved_mem_nr; i++) {
+ sz = crash_reserved_mem[i].end - crash_reserved_mem[i].start +1;
+ if (add_memmap(memmap_p, crash_reserved_mem[i].start, sz) < 0)
+ return ENOCRASHKERNEL;
}
/* Create a backup region segment to store backup data*/
@@ -1093,25 +1089,46 @@ int load_crashdump_segments(struct kexec_info *info, char* mod_cmdline,
return 0;
}
-int is_crashkernel_mem_reserved(void)
+int get_max_crash_kernel_limit(uint64_t *start, uint64_t *end)
{
- uint64_t start, end;
+ int i, idx = -1;
+ unsigned long sz_max = 0, sz;
- if (parse_iomem_single("Crash kernel\n", &start, &end) || start == end)
- return 0;
+ if (!crash_reserved_mem_nr)
+ return -1;
- crash_reserved_mem.start = start;
- crash_reserved_mem.end = end;
- crash_reserved_mem.type = RANGE_RAM;
+ for (i = crash_reserved_mem_nr - 1; i >= 0; i--) {
+ sz = crash_reserved_mem[i].end - crash_reserved_mem[i].start +1;
+ if (sz <= sz_max)
+ continue;
+ sz_max = sz;
+ idx = i;
+ }
+
+ *start = crash_reserved_mem[idx].start;
+ *end = crash_reserved_mem[idx].end;
+
+ return 0;
+}
- /* If there is no Crash low kernel, still can go on */
- if (parse_iomem_single("Crash kernel low\n", &start, &end) ||
- start == end)
+static int crashkernel_mem_callback(void *UNUSED(data), int nr,
+ char *UNUSED(str),
+ unsigned long base,
+ unsigned long length)
+{
+ if (nr >= CRASH_RESERVED_MEM_NR)
return 1;
- crash_reserved_low_mem.start = start;
- crash_reserved_low_mem.end = end;
- crash_reserved_low_mem.type = RANGE_RAM;
+ crash_reserved_mem[nr].start = base;
+ crash_reserved_mem[nr].end = base + length - 1;
+ crash_reserved_mem[nr].type = RANGE_RAM;
+ return 0;
+}
+
+int is_crashkernel_mem_reserved(void)
+{
+ crash_reserved_mem_nr = kexec_iomem_for_each_line("Crash kernel\n",
+ crashkernel_mem_callback, NULL);
- return 1;
+ return !!crash_reserved_mem_nr;
}
diff --git a/kexec/arch/i386/kexec-x86-common.c b/kexec/arch/i386/kexec-x86-common.c
index 234823c..ed6c950 100644
--- a/kexec/arch/i386/kexec-x86-common.c
+++ b/kexec/arch/i386/kexec-x86-common.c
@@ -465,9 +465,9 @@ int get_memory_ranges(struct memory_range **range, int *ranges,
!(kexec_flags & KEXEC_PRESERVE_CONTEXT)) {
uint64_t start, end;
- ret = parse_iomem_single("Crash kernel\n", &start, &end);
+ ret = get_max_crash_kernel_limit(&start, &end);
if (ret != 0) {
- fprintf(stderr, "parse_iomem_single failed.\n");
+ fprintf(stderr, "get_max_crash_kernel_limit failed.\n");
return -1;
}
diff --git a/kexec/kexec.h b/kexec/kexec.h
index 916a24b..5ded390 100644
--- a/kexec/kexec.h
+++ b/kexec/kexec.h
@@ -272,6 +272,7 @@ int arch_process_options(int argc, char **argv);
int arch_compat_trampoline(struct kexec_info *info);
void arch_update_purgatory(struct kexec_info *info);
int is_crashkernel_mem_reserved(void);
+int get_max_crash_kernel_limit(uint64_t *start, uint64_t *end);
char *get_command_line(void);
int kexec_iomem_for_each_line(char *match,
--
1.8.3.1