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authorWill Deacon <will@kernel.org>2022-12-06 11:16:20 +0000
committerWill Deacon <will@kernel.org>2022-12-06 11:16:20 +0000
commit926939c734fdac89cae27c9c93a28c30cde59fff (patch)
tree2f959ec2f17d69e548e79b2a8983460ad20bf0a7 /arch/arm64/mm
parentd864e90585f21e4e66bcf570bd743ca61dc6b7d1 (diff)
parenta9ae89df737756d92f0e14873339cf393f7f7eb0 (diff)
Merge branch 'for-next/kdump' into for-next/core
* for-next/kdump: arm64: kdump: Support crashkernel=X fall back to reserve region above DMA zones arm64: kdump: Provide default size when crashkernel=Y,low is not specified
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r--arch/arm64/mm/init.c25
1 files changed, 22 insertions, 3 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 4b4651ee47f2..58a0bb2c17f1 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -96,6 +96,8 @@ phys_addr_t __ro_after_init arm64_dma_phys_limit = PHYS_MASK + 1;
#define CRASH_ADDR_LOW_MAX arm64_dma_phys_limit
#define CRASH_ADDR_HIGH_MAX (PHYS_MASK + 1)
+#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
+
static int __init reserve_crashkernel_low(unsigned long long low_size)
{
unsigned long long low_base;
@@ -130,6 +132,7 @@ static void __init reserve_crashkernel(void)
unsigned long long crash_max = CRASH_ADDR_LOW_MAX;
char *cmdline = boot_command_line;
int ret;
+ bool fixed_base = false;
if (!IS_ENABLED(CONFIG_KEXEC_CORE))
return;
@@ -147,7 +150,9 @@ static void __init reserve_crashkernel(void)
* is not allowed.
*/
ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
- if (ret && (ret != -ENOENT))
+ if (ret == -ENOENT)
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ else if (ret)
return;
crash_max = CRASH_ADDR_HIGH_MAX;
@@ -159,18 +164,32 @@ static void __init reserve_crashkernel(void)
crash_size = PAGE_ALIGN(crash_size);
/* User specifies base address explicitly. */
- if (crash_base)
+ if (crash_base) {
+ fixed_base = true;
crash_max = crash_base + crash_size;
+ }
+retry:
crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
crash_base, crash_max);
if (!crash_base) {
+ /*
+ * If the first attempt was for low memory, fall back to
+ * high memory, the minimum required low memory will be
+ * reserved later.
+ */
+ if (!fixed_base && (crash_max == CRASH_ADDR_LOW_MAX)) {
+ crash_max = CRASH_ADDR_HIGH_MAX;
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ goto retry;
+ }
+
pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
crash_size);
return;
}
- if ((crash_base >= CRASH_ADDR_LOW_MAX) &&
+ if ((crash_base > CRASH_ADDR_LOW_MAX - crash_low_size) &&
crash_low_size && reserve_crashkernel_low(crash_low_size)) {
memblock_phys_free(crash_base, crash_size);
return;