diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index e16b248699d5..19c2d487cb08 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -329,8 +329,13 @@ bool crash_is_nosave(unsigned long pfn) /* in reserved memory? */ addr = __pfn_to_phys(pfn); - if ((addr < crashk_res.start) || (crashk_res.end < addr)) - return false; + if ((addr < crashk_res.start) || (crashk_res.end < addr)) { + if (!crashk_low_res.end) + return false; + + if ((addr < crashk_low_res.start) || (crashk_low_res.end < addr)) + return false; + } if (!kexec_crash_image) return true; diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c index 59c648d51848..889951291cc0 100644 --- a/arch/arm64/kernel/machine_kexec_file.c +++ b/arch/arm64/kernel/machine_kexec_file.c @@ -65,10 +65,18 @@ static int prepare_elf_headers(void **addr, unsigned long *sz) /* Exclude crashkernel region */ ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); + if (ret) + goto out; - if (!ret) - ret = crash_prepare_elf64_headers(cmem, true, addr, sz); + if (crashk_low_res.end) { + ret = crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end); + if (ret) + goto out; + } + ret = crash_prepare_elf64_headers(cmem, true, addr, sz); + +out: kfree(cmem); return ret; } diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 51863f1448c6..18ba66c90991 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -90,6 +90,32 @@ phys_addr_t __ro_after_init arm64_dma_phys_limit; phys_addr_t __ro_after_init arm64_dma_phys_limit = PHYS_MASK + 1; #endif +/* Current arm64 boot protocol requires 2MB alignment */ +#define CRASH_ALIGN SZ_2M + +#define CRASH_ADDR_LOW_MAX arm64_dma_phys_limit +#define CRASH_ADDR_HIGH_MAX (PHYS_MASK + 1) + +static int __init reserve_crashkernel_low(unsigned long long low_size) +{ + unsigned long long low_base; + + low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX); + if (!low_base) { + pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size); + return -ENOMEM; + } + + pr_info("crashkernel low memory reserved: 0x%08llx - 0x%08llx (%lld MB)\n", + low_base, low_base + low_size, low_size >> 20); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; + insert_resource(&iomem_resource, &crashk_low_res); + + return 0; +} + /* * reserve_crashkernel() - reserves memory for crash kernel * @@ -100,17 +126,35 @@ phys_addr_t __ro_after_init arm64_dma_phys_limit = PHYS_MASK + 1; static void __init reserve_crashkernel(void) { unsigned long long crash_base, crash_size; - unsigned long long crash_max = arm64_dma_phys_limit; + unsigned long long crash_low_size = 0; + unsigned long long crash_max = CRASH_ADDR_LOW_MAX; + char *cmdline = boot_command_line; int ret; if (!IS_ENABLED(CONFIG_KEXEC_CORE)) return; - ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), + /* crashkernel=X[@offset] */ + ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), &crash_size, &crash_base); - /* no crashkernel= or invalid value specified */ - if (ret || !crash_size) + if (ret == -ENOENT) { + ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base); + if (ret || !crash_size) + return; + + /* + * crashkernel=Y,low can be specified or not, but invalid value + * is not allowed. + */ + ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base); + if (ret && (ret != -ENOENT)) + return; + + crash_max = CRASH_ADDR_HIGH_MAX; + } else if (ret || !crash_size) { + /* The specified value is invalid */ return; + } crash_size = PAGE_ALIGN(crash_size); @@ -118,8 +162,7 @@ static void __init reserve_crashkernel(void) if (crash_base) crash_max = crash_base + crash_size; - /* Current arm64 boot protocol requires 2MB alignment */ - crash_base = memblock_phys_alloc_range(crash_size, SZ_2M, + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, crash_base, crash_max); if (!crash_base) { pr_warn("cannot allocate crashkernel (size:0x%llx)\n", @@ -127,6 +170,11 @@ static void __init reserve_crashkernel(void) return; } + if (crash_low_size && reserve_crashkernel_low(crash_low_size)) { + memblock_phys_free(crash_base, crash_size); + return; + } + pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", crash_base, crash_base + crash_size, crash_size >> 20); @@ -135,6 +183,9 @@ static void __init reserve_crashkernel(void) * map. Inform kmemleak so that it won't try to access it. */ kmemleak_ignore_phys(crash_base); + if (crashk_low_res.end) + kmemleak_ignore_phys(crashk_low_res.start); + crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; insert_resource(&iomem_resource, &crashk_res);