powerpc/fadump: process the crashdump by exporting it as /proc/vmcore (2a1b06dd) · Commits · EulixOS / Software / Kernel

arch/powerpc/platforms/powernv/opal-fadump.c

+145 −2

Original line number	Diff line number	Diff line
		@@ -12,6 +12,7 @@
		#include <linux/of_fdt.h>
		#include <linux/libfdt.h>
		#include <linux/mm.h>
		#include <linux/crash_dump.h>

		#include <asm/page.h>
		#include <asm/opal.h>
		@@ -19,6 +20,7 @@

		#include "opal-fadump.h"

		static const struct opal_fadump_mem_struct *opal_fdm_active;
		static struct opal_fadump_mem_struct *opal_fdm;

		static int opal_fadump_unregister(struct fw_dump *fadump_conf);
		@@ -39,6 +41,37 @@ static void opal_fadump_update_config(struct fw_dump *fadump_conf,
		fadump_conf->fadumphdr_addr = fdm->fadumphdr_addr;
		}

		/*
		* This function is called in the capture kernel to get configuration details
		* from metadata setup by the first kernel.
		*/
		static void opal_fadump_get_config(struct fw_dump *fadump_conf,
		const struct opal_fadump_mem_struct *fdm)
		{
		int i;

		if (!fadump_conf->dump_active)
		return;

		fadump_conf->boot_memory_size = 0;

		pr_debug("Boot memory regions:\n");
		for (i = 0; i < fdm->region_cnt; i++) {
		pr_debug("\t%d. base: 0x%llx, size: 0x%llx\n",
		(i + 1), fdm->rgn[i].src, fdm->rgn[i].size);

		fadump_conf->boot_memory_size += fdm->rgn[i].size;
		}

		/*
		* Start address of reserve dump area (permanent reservation) for
		* re-registering FADump after dump capture.
		*/
		fadump_conf->reserve_dump_area_start = fdm->rgn[0].dest;

		opal_fadump_update_config(fadump_conf, fdm);
		}

		/* Initialize kernel metadata */
		static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm)
		{
		@@ -209,24 +242,97 @@ static void opal_fadump_cleanup(struct fw_dump *fadump_conf)
		pr_warn("Could not reset (%llu) kernel metadata tag!\n", ret);
		}

		/*
		* Convert CPU state data saved at the time of crash into ELF notes.
		*
		* Append crashing CPU's register data saved by the kernel in the PT_NOTE.
		*/
		static int __init
		opal_fadump_build_cpu_notes(struct fw_dump *fadump_conf,
		struct fadump_crash_info_header *fdh)
		{
		u32 num_cpus = 1, *note_buf;
		int rc;

		if (fdh->crashing_cpu == FADUMP_CPU_UNKNOWN)
		return -ENODEV;

		/* Allocate CPU notes buffer to hold crashing cpu notes. */
		rc = fadump_setup_cpu_notes_buf(num_cpus);
		if (rc != 0)
		return rc;

		note_buf = (u32 *)fadump_conf->cpu_notes_buf_vaddr;
		note_buf = fadump_regs_to_elf_notes(note_buf, &(fdh->regs));
		final_note(note_buf);

		pr_debug("Updating elfcore header (%llx) with cpu notes\n",
		fdh->elfcorehdr_addr);
		fadump_update_elfcore_header(__va(fdh->elfcorehdr_addr));
		return 0;
		}

		static int __init opal_fadump_process(struct fw_dump *fadump_conf)
		{
		return -EINVAL;
		struct fadump_crash_info_header *fdh;
		int rc = -EINVAL;

		if (!opal_fdm_active \|\| !fadump_conf->fadumphdr_addr)
		return rc;

		/* Validate the fadump crash info header */
		fdh = __va(fadump_conf->fadumphdr_addr);
		if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) {
		pr_err("Crash info header is not valid.\n");
		return rc;
		}

		rc = opal_fadump_build_cpu_notes(fadump_conf, fdh);
		if (rc)
		return rc;

		/*
		* We are done validating dump info and elfcore header is now ready
		* to be exported. set elfcorehdr_addr so that vmcore module will
		* export the elfcore header through '/proc/vmcore'.
		*/
		elfcorehdr_addr = fdh->elfcorehdr_addr;

		return rc;
		}

		static void opal_fadump_region_show(struct fw_dump *fadump_conf,
		struct seq_file *m)
		{
		const struct opal_fadump_mem_struct *fdm_ptr = opal_fdm;
		const struct opal_fadump_mem_struct *fdm_ptr;
		u64 dumped_bytes = 0;
		int i;

		if (fadump_conf->dump_active)
		fdm_ptr = opal_fdm_active;
		else
		fdm_ptr = opal_fdm;

		for (i = 0; i < fdm_ptr->region_cnt; i++) {
		/*
		* Only regions that are registered for MPIPL
		* would have dump data.
		*/
		if ((fadump_conf->dump_active) &&
		(i < fdm_ptr->registered_regions))
		dumped_bytes = fdm_ptr->rgn[i].size;

		seq_printf(m, "DUMP: Src: %#016llx, Dest: %#016llx, ",
		fdm_ptr->rgn[i].src, fdm_ptr->rgn[i].dest);
		seq_printf(m, "Size: %#llx, Dumped: %#llx bytes\n",
		fdm_ptr->rgn[i].size, dumped_bytes);
		}

		/* Dump is active. Show reserved area start address. */
		if (fadump_conf->dump_active) {
		seq_printf(m, "\nMemory above %#016lx is reserved for saving crash dump\n",
		fadump_conf->reserve_dump_area_start);
		}
		}

		static void opal_fadump_trigger(struct fadump_crash_info_header *fdh,
		@@ -257,7 +363,11 @@ static struct fadump_ops opal_fadump_ops = {

		void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node)
		{
		const __be32 *prop;
		unsigned long dn;
		u64 addr = 0;
		s64 ret;


		/*
		* Check if Firmware-Assisted Dump is supported. if yes, check
		@@ -276,4 +386,37 @@ void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node)

		fadump_conf->ops = &opal_fadump_ops;
		fadump_conf->fadump_supported = 1;

		/*
		* Check if dump has been initiated on last reboot.
		*/
		prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL);
		if (!prop)
		return;

		ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr);
		if ((ret != OPAL_SUCCESS) \|\| !addr) {
		pr_err("Failed to get Kernel metadata (%lld)\n", ret);
		return;
		}

		addr = be64_to_cpu(addr);
		pr_debug("Kernel metadata addr: %llx\n", addr);

		opal_fdm_active = __va(addr);
		if (opal_fdm_active->version != OPAL_FADUMP_VERSION) {
		pr_warn("Supported kernel metadata version: %u, found: %d!\n",
		OPAL_FADUMP_VERSION, opal_fdm_active->version);
		pr_warn("WARNING: Kernel metadata format mismatch identified! Core file maybe corrupted..\n");
		}

		/* Kernel regions not registered with f/w for MPIPL */
		if (opal_fdm_active->registered_regions == 0) {
		opal_fdm_active = NULL;
		return;
		}

		pr_info("Firmware-assisted dump is active.\n");
		fadump_conf->dump_active = 1;
		opal_fadump_get_config(fadump_conf, opal_fdm_active);
		}