diff options
author | Zhen Lei <[email protected]> | 2022-11-16 20:10:44 +0800 |
---|---|---|
committer | Will Deacon <[email protected]> | 2022-11-18 14:14:35 +0000 |
commit | a9ae89df737756d92f0e14873339cf393f7f7eb0 (patch) | |
tree | 62be9596eeb9d5b7e27cdae5aa87b0ea1746a4b3 | |
parent | a149cf00b158e1793a8dd89ca492379c366300d2 (diff) |
arm64: kdump: Support crashkernel=X fall back to reserve region above DMA zones
For crashkernel=X without '@offset', select a region within DMA zones
first, and fall back to reserve region above DMA zones. This allows
users to use the same configuration on multiple platforms.
Signed-off-by: Zhen Lei <[email protected]>
Acked-by: Baoquan He <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 2 | ||||
-rw-r--r-- | arch/arm64/mm/init.c | 17 |
2 files changed, 17 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6c6fafc3fba9..9d458dfbec5f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -831,7 +831,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, X86-64] Select a region under 4G first, and + [KNL, X86-64, ARM64] Select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/admin-guide/kdump/kdump.rst for further details. diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index ba7227179822..58a0bb2c17f1 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -132,6 +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; @@ -163,12 +164,26 @@ 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; |