aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/kdump/kdump.txt13
-rw-r--r--arch/arm/kernel/setup.c29
2 files changed, 32 insertions, 10 deletions
diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt
index bc4bd5a44b88..88ff63d5fde3 100644
--- a/Documentation/kdump/kdump.txt
+++ b/Documentation/kdump/kdump.txt
@@ -263,12 +263,6 @@ The syntax is:
crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset]
range=start-[end]
-Please note, on arm, the offset is required.
- crashkernel=<range1>:<size1>[,<range2>:<size2>,...]@offset
- range=start-[end]
-
- 'start' is inclusive and 'end' is exclusive.
-
For example:
crashkernel=512M-2G:64M,2G-:128M
@@ -307,10 +301,9 @@ Boot into System Kernel
on the memory consumption of the kdump system. In general this is not
dependent on the memory size of the production system.
- On arm, use "crashkernel=Y@X". Note that the start address of the kernel
- will be aligned to 128MiB (0x08000000), so if the start address is not then
- any space below the alignment point may be overwritten by the dump-capture kernel,
- which means it is possible that the vmcore is not that precise as expected.
+ On arm, the use of "crashkernel=Y@X" is no longer necessary; the
+ kernel will automatically locate the crash kernel image within the
+ first 512MB of RAM if X is not given.
Load the Dump-capture Kernel
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 139791ed473d..77b54c461c52 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -938,6 +938,13 @@ static int __init init_machine_late(void)
late_initcall(init_machine_late);
#ifdef CONFIG_KEXEC
+/*
+ * The crash region must be aligned to 128MB to avoid
+ * zImage relocating below the reserved region.
+ */
+#define CRASH_ALIGN (128 << 20)
+#define CRASH_ADDR_MAX (PHYS_OFFSET + (512 << 20))
+
static inline unsigned long long get_total_mem(void)
{
unsigned long total;
@@ -965,6 +972,28 @@ static void __init reserve_crashkernel(void)
if (ret)
return;
+ if (crash_base <= 0) {
+ unsigned long long crash_max = CRASH_ADDR_MAX;
+ if (crash_max > (u32)~0)
+ crash_max = (u32)~0;
+ crash_base = memblock_find_in_range(CRASH_ALIGN, crash_max,
+ crash_size, CRASH_ALIGN);
+ if (!crash_base) {
+ pr_err("crashkernel reservation failed - No suitable area found.\n");
+ return;
+ }
+ } else {
+ unsigned long long start;
+
+ start = memblock_find_in_range(crash_base,
+ crash_base + crash_size,
+ crash_size, SECTION_SIZE);
+ if (start != crash_base) {
+ pr_err("crashkernel reservation failed - memory is in use.\n");
+ return;
+ }
+ }
+
ret = memblock_reserve(crash_base, crash_size);
if (ret < 0) {
pr_warn("crashkernel reservation failed - memory is in use (0x%lx)\n",