[PATCH v6 8/9] arm64: kdump: add DT properties to crash dump kernel's dtb
AKASHI Takahiro
takahiro.akashi at linaro.org
Wed Mar 15 02:38:23 PDT 2017
We pass the following properties to crash dump kernel:
linux,elfcorehdr: elf core header segment,
same as "elfcorehdr=" kernel parameter on other archs
linux,usable-memory-range: usable memory reserved for crash dump kernel
Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
---
kexec/arch/arm64/kexec-arm64.c | 197 ++++++++++++++++++++++++++++++++++++-
kexec/arch/arm64/kexec-elf-arm64.c | 5 -
2 files changed, 192 insertions(+), 10 deletions(-)
diff --git a/kexec/arch/arm64/kexec-arm64.c b/kexec/arch/arm64/kexec-arm64.c
index 5e30107..f3f101d 100644
--- a/kexec/arch/arm64/kexec-arm64.c
+++ b/kexec/arch/arm64/kexec-arm64.c
@@ -25,6 +25,14 @@
#include "kexec-syscall.h"
#include "arch/options.h"
+#define ROOT_NODE_ADDR_CELLS_DEFAULT 1
+#define ROOT_NODE_SIZE_CELLS_DEFAULT 1
+
+#define PROP_ADDR_CELLS "#address-cells"
+#define PROP_SIZE_CELLS "#size-cells"
+#define PROP_ELFCOREHDR "linux,elfcorehdr"
+#define PROP_USABLE_MEM_RANGE "linux,usable-memory-range"
+
/* Global varables the core kexec routines expect. */
unsigned char reuse_initrd;
@@ -128,9 +136,6 @@ int arch_process_options(int argc, char **argv)
case OPT_INITRD:
arm64_opts.initrd = optarg;
break;
- case OPT_PANIC:
- die("load-panic (-p) not supported");
- break;
default:
break; /* Ignore core and unknown options. */
}
@@ -281,12 +286,115 @@ on_success:
return 0;
}
+static int get_cells_size(void *fdt, uint32_t *address_cells,
+ uint32_t *size_cells)
+{
+ int nodeoffset;
+ const uint32_t *prop = NULL;
+ int prop_len;
+
+ /* default values */
+ *address_cells = ROOT_NODE_ADDR_CELLS_DEFAULT;
+ *size_cells = ROOT_NODE_SIZE_CELLS_DEFAULT;
+
+ /* under root node */
+ nodeoffset = fdt_path_offset(fdt, "/");
+ if (nodeoffset < 0)
+ goto on_error;
+
+ prop = fdt_getprop(fdt, nodeoffset, PROP_ADDR_CELLS, &prop_len);
+ if (prop) {
+ if (prop_len == sizeof(*prop))
+ *address_cells = fdt32_to_cpu(*prop);
+ else
+ goto on_error;
+ }
+
+ prop = fdt_getprop(fdt, nodeoffset, PROP_SIZE_CELLS, &prop_len);
+ if (prop) {
+ if (prop_len == sizeof(*prop))
+ *size_cells = fdt32_to_cpu(*prop);
+ else
+ goto on_error;
+ }
+
+ dbgprintf("%s: #address-cells:%d #size-cells:%d\n", __func__,
+ *address_cells, *size_cells);
+ return 0;
+
+on_error:
+ return -EFAILED;
+}
+
+bool cells_size_fitted(uint32_t address_cells, uint32_t size_cells,
+ struct memory_range *range)
+{
+ dbgprintf("%s: %llx-%llx\n", __func__, range->start, range->end);
+
+ /* if *_cells >= 2, cells can hold 64-bit values anyway */
+ if ((address_cells == 1) && (range->start >= (1ULL << 32)))
+ return false;
+
+ if ((size_cells == 1) &&
+ ((range->end - range->start + 1) >= (1ULL << 32)))
+ return false;
+
+ return true;
+}
+
+static void fill_property(void *buf, uint64_t val, uint32_t cells)
+{
+ uint32_t val32;
+ int i;
+
+ if (cells == 1) {
+ val32 = cpu_to_fdt32((uint32_t)val);
+ memcpy(buf, &val32, sizeof(uint32_t));
+ } else {
+ for (i = 0;
+ i < (cells * sizeof(uint32_t) - sizeof(uint64_t)); i++)
+ *(char *)buf++ = 0;
+
+ val = cpu_to_fdt64(val);
+ memcpy(buf, &val, sizeof(uint64_t));
+ }
+}
+
+static int setprop_range(void *fdt, int nodeoffset,
+ const char *name, struct memory_range *range,
+ uint32_t address_cells, uint32_t size_cells)
+{
+ void *buf, *prop;
+ size_t buf_size;
+ int result;
+
+ buf_size = (address_cells + size_cells) * sizeof(uint32_t);
+ prop = buf = xmalloc(buf_size);
+
+ fill_property(prop, range->start, address_cells);
+ prop += address_cells * sizeof(uint32_t);
+
+ fill_property(prop, range->end - range->start + 1, size_cells);
+ prop += size_cells * sizeof(uint32_t);
+
+ result = fdt_setprop(fdt, nodeoffset, name, buf, buf_size);
+
+ free(buf);
+
+ return result;
+}
+
/**
* setup_2nd_dtb - Setup the 2nd stage kernel's dtb.
*/
-static int setup_2nd_dtb(struct dtb *dtb, char *command_line)
+static int setup_2nd_dtb(struct dtb *dtb, char *command_line, int on_crash)
{
+ uint32_t address_cells, size_cells;
+ int range_len;
+ int nodeoffset;
+ char *new_buf = NULL;
+ int new_size;
int result;
result = fdt_check_header(dtb->buf);
@@ -298,8 +406,86 @@ static int setup_2nd_dtb(struct dtb *dtb, char *command_line)
result = set_bootargs(dtb, command_line);
+ if (on_crash) {
+ /* determine #address-cells and #size-cells */
+ result = get_cells_size(dtb->buf, &address_cells, &size_cells);
+ if (result) {
+ fprintf(stderr,
+ "kexec: cannot determine cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ if (!cells_size_fitted(address_cells, size_cells,
+ &elfcorehdr_mem)) {
+ fprintf(stderr,
+ "kexec: elfcorehdr doesn't fit cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ if (!cells_size_fitted(address_cells, size_cells,
+ &crash_reserved_mem)) {
+ fprintf(stderr,
+ "kexec: usable memory range doesn't fit cells-size.\n");
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ /* duplicate dt blob */
+ range_len = sizeof(uint32_t) * (address_cells + size_cells);
+ new_size = fdt_totalsize(dtb->buf)
+ + fdt_prop_len(PROP_ELFCOREHDR, range_len)
+ + fdt_prop_len(PROP_USABLE_MEM_RANGE, range_len);
+
+ new_buf = xmalloc(new_size);
+ result = fdt_open_into(dtb->buf, new_buf, new_size);
+ if (result) {
+ dbgprintf("%s: fdt_open_into failed: %s\n", __func__,
+ fdt_strerror(result));
+ result = -ENOSPC;
+ goto on_error;
+ }
+
+ /* add linux,elfcorehdr */
+ nodeoffset = fdt_path_offset(new_buf, "/chosen");
+ result = setprop_range(new_buf, nodeoffset,
+ PROP_ELFCOREHDR, &elfcorehdr_mem,
+ address_cells, size_cells);
+ if (result) {
+ dbgprintf("%s: fdt_setprop failed: %s\n", __func__,
+ fdt_strerror(result));
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ /* add linux,usable-memory-range */
+ nodeoffset = fdt_path_offset(new_buf, "/chosen");
+ result = setprop_range(new_buf, nodeoffset,
+ PROP_USABLE_MEM_RANGE, &crash_reserved_mem,
+ address_cells, size_cells);
+ if (result) {
+ dbgprintf("%s: fdt_setprop failed: %s\n", __func__,
+ fdt_strerror(result));
+ result = -EINVAL;
+ goto on_error;
+ }
+
+ fdt_pack(new_buf);
+ dtb->buf = new_buf;
+ dtb->size = fdt_totalsize(new_buf);
+ }
+
dump_reservemap(dtb);
+
+ return result;
+
+on_error:
+ fprintf(stderr, "kexec: %s failed.\n", __func__);
+ if (new_buf)
+ free(new_buf);
+
return result;
}
@@ -367,7 +553,8 @@ int arm64_load_other_segments(struct kexec_info *info,
}
}
- result = setup_2nd_dtb(&dtb, command_line);
+ result = setup_2nd_dtb(&dtb, command_line,
+ info->kexec_flags & KEXEC_ON_CRASH);
if (result)
return -EFAILED;
diff --git a/kexec/arch/arm64/kexec-elf-arm64.c b/kexec/arch/arm64/kexec-elf-arm64.c
index 842ce21..b17a31a 100644
--- a/kexec/arch/arm64/kexec-elf-arm64.c
+++ b/kexec/arch/arm64/kexec-elf-arm64.c
@@ -47,11 +47,6 @@ int elf_arm64_load(int argc, char **argv, const char *kernel_buf,
int result;
int i;
- if (info->kexec_flags & KEXEC_ON_CRASH) {
- fprintf(stderr, "kexec: kdump not yet supported on arm64\n");
- return -EFAILED;
- }
-
result = build_elf_exec_info(kernel_buf, kernel_size, &ehdr, 0);
if (result < 0) {
--
2.11.1
More information about the kexec
mailing list