diff options
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/Kconfig | 4 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/kexec.h | 8 | ||||
| -rw-r--r-- | arch/powerpc/kexec/crash.c | 103 | ||||
| -rw-r--r-- | arch/powerpc/kexec/elf_64.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/kexec/file_load_64.c | 17 |
5 files changed, 134 insertions, 1 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 1c4be3373686..a1a3b3363008 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -686,6 +686,10 @@ config ARCH_SELECTS_CRASH_DUMP depends on CRASH_DUMP select RELOCATABLE if PPC64 || 44x || PPC_85xx +config ARCH_SUPPORTS_CRASH_HOTPLUG + def_bool y + depends on PPC64 + config FA_DUMP bool "Firmware-assisted dump" depends on CRASH_DUMP && PPC64 && (PPC_RTAS || PPC_POWERNV) diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index d9ff4d0e392d..e75970351bcd 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -135,6 +135,14 @@ static inline void crash_setup_regs(struct pt_regs *newregs, ppc_save_regs(newregs); } +#ifdef CONFIG_CRASH_HOTPLUG +void arch_crash_handle_hotplug_event(struct kimage *image, void *arg); +#define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event + +int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags); +#define arch_crash_hotplug_support arch_crash_hotplug_support +#endif /* CONFIG_CRASH_HOTPLUG */ + extern int crashing_cpu; extern void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *)); extern void crash_ipi_callback(struct pt_regs *regs); diff --git a/arch/powerpc/kexec/crash.c b/arch/powerpc/kexec/crash.c index ef5c2d25ec39..8938a19af12f 100644 --- a/arch/powerpc/kexec/crash.c +++ b/arch/powerpc/kexec/crash.c @@ -16,6 +16,7 @@ #include <linux/delay.h> #include <linux/irq.h> #include <linux/types.h> +#include <linux/libfdt.h> #include <asm/processor.h> #include <asm/machdep.h> @@ -392,3 +393,105 @@ void default_machine_crash_shutdown(struct pt_regs *regs) if (ppc_md.kexec_cpu_down) ppc_md.kexec_cpu_down(1, 0); } + +#ifdef CONFIG_CRASH_HOTPLUG +#undef pr_fmt +#define pr_fmt(fmt) "crash hp: " fmt + +/** + * get_fdt_index - Loop through the kexec segment array and find + * the index of the FDT segment. + * @image: a pointer to kexec_crash_image + * + * Returns the index of FDT segment in the kexec segment array + * if found; otherwise -1. + */ +static int get_fdt_index(struct kimage *image) +{ + void *ptr; + unsigned long mem; + int i, fdt_index = -1; + + /* Find the FDT segment index in kexec segment array. */ + for (i = 0; i < image->nr_segments; i++) { + mem = image->segment[i].mem; + ptr = __va(mem); + + if (ptr && fdt_magic(ptr) == FDT_MAGIC) { + fdt_index = i; + break; + } + } + + return fdt_index; +} + +/** + * update_crash_fdt - updates the cpus node of the crash FDT. + * + * @image: a pointer to kexec_crash_image + */ +static void update_crash_fdt(struct kimage *image) +{ + void *fdt; + int fdt_index; + + fdt_index = get_fdt_index(image); + if (fdt_index < 0) { + pr_err("Unable to locate FDT segment.\n"); + return; + } + + fdt = __va((void *)image->segment[fdt_index].mem); + + /* Temporarily invalidate the crash image while it is replaced */ + xchg(&kexec_crash_image, NULL); + + /* update FDT to reflect changes in CPU resources */ + if (update_cpus_node(fdt)) + pr_err("Failed to update crash FDT"); + + /* The crash image is now valid once again */ + xchg(&kexec_crash_image, image); +} + +int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags) +{ +#ifdef CONFIG_KEXEC_FILE + if (image->file_mode) + return 1; +#endif + return kexec_flags & KEXEC_CRASH_HOTPLUG_SUPPORT; +} + +/** + * arch_crash_handle_hotplug_event - Handle crash CPU/Memory hotplug events to update the + * necessary kexec segments based on the hotplug event. + * @image: a pointer to kexec_crash_image + * @arg: struct memory_notify handler for memory hotplug case and NULL for CPU hotplug case. + * + * Update the kdump image based on the type of hotplug event, represented by image->hp_action. + * CPU add: Update the FDT segment to include the newly added CPU. + * CPU remove: No action is needed, with the assumption that it's okay to have offline CPUs + * part of the FDT. + * Memory add/remove: No action is taken as this is not yet supported. + */ +void arch_crash_handle_hotplug_event(struct kimage *image, void *arg) +{ + switch (image->hp_action) { + case KEXEC_CRASH_HP_REMOVE_CPU: + return; + + case KEXEC_CRASH_HP_ADD_CPU: + update_crash_fdt(image); + break; + + case KEXEC_CRASH_HP_REMOVE_MEMORY: + case KEXEC_CRASH_HP_ADD_MEMORY: + pr_info_once("Crash update is not supported for memory hotplug\n"); + return; + default: + pr_warn_once("Unknown hotplug action\n"); + } +} +#endif /* CONFIG_CRASH_HOTPLUG */ diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c index 6d8951e8e966..214c071c58ed 100644 --- a/arch/powerpc/kexec/elf_64.c +++ b/arch/powerpc/kexec/elf_64.c @@ -116,7 +116,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, if (ret) goto out_free_fdt; - fdt_pack(fdt); + if (!IS_ENABLED(CONFIG_CRASH_HOTPLUG) || image->type != KEXEC_TYPE_CRASH) + fdt_pack(fdt); kbuf.buffer = fdt; kbuf.bufsz = kbuf.memsz = fdt_totalsize(fdt); diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c index 4b94c31e3172..2640a804fcdf 100644 --- a/arch/powerpc/kexec/file_load_64.c +++ b/arch/powerpc/kexec/file_load_64.c @@ -30,6 +30,7 @@ #include <asm/iommu.h> #include <asm/prom.h> #include <asm/plpks.h> +#include <asm/cputhreads.h> struct umem_info { __be64 *buf; /* data buffer for usable-memory property */ @@ -789,6 +790,9 @@ static unsigned int kdump_extra_fdt_size_ppc64(struct kimage *image) unsigned int cpu_nodes, extra_size = 0; struct device_node *dn; u64 usm_entries; +#ifdef CONFIG_CRASH_HOTPLUG + unsigned int possible_cpu_nodes; +#endif if (!IS_ENABLED(CONFIG_CRASH_DUMP) || image->type != KEXEC_TYPE_CRASH) return 0; @@ -816,6 +820,19 @@ static unsigned int kdump_extra_fdt_size_ppc64(struct kimage *image) if (cpu_nodes > boot_cpu_node_count) extra_size += (cpu_nodes - boot_cpu_node_count) * cpu_node_size(); +#ifdef CONFIG_CRASH_HOTPLUG + /* + * Make sure enough space is reserved to accommodate possible CPU nodes + * in the crash FDT. This allows packing possible CPU nodes which are + * not yet present in the system without regenerating the entire FDT. + */ + if (image->type == KEXEC_TYPE_CRASH) { + possible_cpu_nodes = num_possible_cpus() / threads_per_core; + if (possible_cpu_nodes > cpu_nodes) + extra_size += (possible_cpu_nodes - cpu_nodes) * cpu_node_size(); + } +#endif + return extra_size; } |