From: Hari Bathini <hbath...@linux.vnet.ibm.com>
Export /proc/opaldump file to analyze opal crashes
Signed-off-by: Hari Bathini <hbath...@linux.vnet.ibm.com>
---
arch/powerpc/platforms/powernv/Makefile | 2
arch/powerpc/platforms/powernv/opalcore.c | 282 +++++++++++++++++++++++
arch/powerpc/platforms/powernv/opalcore.h | 28 ++
arch/powerpc/platforms/powernv/powernv_fadump.c | 52 ++++
4 files changed, 358 insertions(+), 6 deletions(-)
create mode 100644 arch/powerpc/platforms/powernv/opalcore.c
create mode 100644 arch/powerpc/platforms/powernv/opalcore.h
diff --git a/arch/powerpc/platforms/powernv/Makefile
b/arch/powerpc/platforms/powernv/Makefile
index 0d106b5..31f828f 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -6,7 +6,7 @@ obj-y += opal-msglog.o opal-hmi.o
opal-power.o opal-irqchip.o
obj-y += opal-kmsg.o opal-powercap.o opal-psr.o
opal-sensor-groups.o
obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o
-obj-$(CONFIG_FA_DUMP) += powernv_fadump.o
+obj-$(CONFIG_FA_DUMP) += powernv_fadump.o opalcore.o
obj-$(CONFIG_PCI) += pci.o pci-ioda.o npu-dma.o
obj-$(CONFIG_CXL_BASE) += pci-cxl.o
obj-$(CONFIG_EEH) += eeh-powernv.o
diff --git a/arch/powerpc/platforms/powernv/opalcore.c
b/arch/powerpc/platforms/powernv/opalcore.c
new file mode 100644
index 0000000..d233d9a
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opalcore.c
@@ -0,0 +1,282 @@
+/*
+ * Interface for exporting the OPAL ELF core.
+ * Loosely based on fs/proc/vmcore.c
+ *
+ * Copyright 2018, IBM Corporation
+ * Author: Hari Bathini <hbath...@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/memblock.h>
+#include <linux/uaccess.h>
+#include <linux/proc_fs.h>
+#include <linux/elf.h>
+#include <linux/elfcore.h>
+#include <linux/crash_core.h>
+
+#include <asm/page.h>
+
+#include "opalcore.h"
+
+/* Total size of opalcore file. */
+static size_t opalcore_size;
+
+/* This buffer includes all the ELF core headers and the PT_NOTE */
+static char *opalcorebuf;
+static size_t opalcorebuf_sz;
+
+/* Pointer to the first PT_LOAD in the ELF file */
+Elf64_Phdr *ptload_phdr;
+unsigned int ptload_cnt;
+
+static struct proc_dir_entry *proc_opalcore;
+
+static inline int is_opalcore_usable(void)
+{
+ return (opalcorebuf != NULL) ? 1 : 0;
+}
+
+static Elf64_Word *append_elf64_note(Elf64_Word *buf, char *name,
+ unsigned int type, void *data,
+ size_t data_len)
+{
+ Elf64_Nhdr *note = (Elf64_Nhdr *)buf;
+ Elf64_Word namesz = strlen(name) + 1;
+
+ note->n_namesz = cpu_to_be32(strlen(name) + 1);
+ note->n_descsz = cpu_to_be32(data_len);
+ note->n_type = cpu_to_be32(type);
+ buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf64_Word));
+ memcpy(buf, name, namesz);
+ buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf64_Word));
+ memcpy(buf, data, data_len);
+ buf += DIV_ROUND_UP(data_len, sizeof(Elf64_Word));
+
+ return buf;
+}
+
+static void final_elf64_note(Elf64_Word *buf)
+{
+ memset(buf, 0, sizeof(Elf64_Nhdr));
+}
+
+static Elf64_Word *regs_to_elf64_notes(Elf64_Word *buf, struct pt_regs *regs)
+{
+ struct elf_prstatus prstatus;
+
+ memset(&prstatus, 0, sizeof(prstatus));
+ elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
+ buf = append_elf64_note(buf, CRASH_CORE_NOTE_NAME, NT_PRSTATUS,
+ &prstatus, sizeof(prstatus));
+ return buf;
+}
+
+/*
+ * Read from the ELF header and then the crash dump.
+ * Returns number of bytes read on success, -errno on failure.
+ */
+static ssize_t read_opalcore(struct file *file, char __user *buffer,
+ size_t buflen, loff_t *fpos)
+{
+ Elf64_Phdr *phdr = ptload_phdr;
+ ssize_t tsz, acc = 0;
+ int i;
+
+ if (buflen == 0 || *fpos >= opalcore_size)
+ return 0;
+
+ /* Read ELF core header and/or PT_NOTE segment */
+ if (*fpos < opalcorebuf_sz) {
+ tsz = min(opalcorebuf_sz - (size_t)*fpos, buflen);
+ if (copy_to_user(buffer, opalcorebuf + *fpos, tsz))
+ return -EFAULT;
+ buflen -= tsz;
+ *fpos += tsz;
+ buffer += tsz;
+ acc += tsz;
+
+ /* leave now if filled buffer already */
+ if (buflen == 0)
+ return acc;
+ }
+
+ if ((phdr == NULL) || (ptload_cnt == 0))
+ return -EFAULT;
+
+ for (i = 0; i < ptload_cnt; i++) {
+ uint64_t end = (be64_to_cpu(phdr->p_offset) +
+ be64_to_cpu(phdr->p_memsz));
+
+ if (*fpos < end) {
+ void *addr;
+
+ tsz = (size_t)min_t(unsigned long long,
+ (end - *fpos),
+ buflen);
+ addr = (void *)(be64_to_cpu(phdr->p_vaddr) + *fpos -
+ be64_to_cpu(phdr->p_offset));
+ if (copy_to_user(buffer, addr, tsz))
+ return -EFAULT;
+ buflen -= tsz;
+ *fpos += tsz;
+ buffer += tsz;
+ acc += tsz;
+
+ /* leave now if filled buffer already */
+ if (buflen == 0)
+ return acc;
+ }
+ phdr++;
+ }
+
+ return acc;
+}
+
+static const struct file_operations proc_opalcore_operations = {
+ .read = read_opalcore,
+};
+
+int __init create_opalcore(struct opalcore_config *oc_conf)
+{
+ unsigned long hdr_size, order, count, paddr, i;
+ Elf64_Ehdr *elf;
+ Elf64_Phdr *phdr;
+ loff_t opalcore_off;
+ struct page *page;
+ char *bufp;
+
+ if (opalcorebuf || (oc_conf->ptload_cnt == 0) ||
+ (oc_conf->ptload_cnt > MAX_PT_LOAD_CNT))
+ return -EINVAL;
+
+ hdr_size = (sizeof(Elf64_Ehdr) +
+ ((oc_conf->ptload_cnt + 1) * sizeof(Elf64_Phdr)));
+ opalcorebuf_sz = (hdr_size + oc_conf->cpu_notes_buf_size);
+ order = get_order(opalcorebuf_sz);
+ opalcorebuf = (char *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, order);
+ if (!opalcorebuf)
+ return -ENOMEM;
+
+ count = 1 << order;
+ page = virt_to_page(opalcorebuf);
+ for (i = 0; i < count; i++)
+ SetPageReserved(page + i);
+
+ /* Use count to keep track of the program headers */
+ count = 0;
+
+ bufp = opalcorebuf;
+ elf = (Elf64_Ehdr *)bufp;
+ bufp += sizeof(Elf64_Ehdr);
+ memcpy(elf->e_ident, ELFMAG, SELFMAG);
+ elf->e_ident[EI_CLASS] = ELF_CLASS;
+ elf->e_ident[EI_DATA] = ELFDATA2MSB;
+ elf->e_ident[EI_VERSION] = EV_CURRENT;
+ elf->e_ident[EI_OSABI] = ELF_OSABI;
+ memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
+ elf->e_type = cpu_to_be16(ET_CORE);
+ elf->e_machine = cpu_to_be16(ELF_ARCH);
+ elf->e_version = cpu_to_be32(EV_CURRENT);
+ elf->e_entry = 0;
+ elf->e_phoff = cpu_to_be64(sizeof(Elf64_Ehdr));
+ elf->e_shoff = 0;
+ elf->e_flags = 0;
+
+ elf->e_ehsize = cpu_to_be16(sizeof(Elf64_Ehdr));
+ elf->e_phentsize = cpu_to_be16(sizeof(Elf64_Phdr));
+ elf->e_phnum = 0;
+ elf->e_shentsize = 0;
+ elf->e_shnum = 0;
+ elf->e_shstrndx = 0;
+
+ phdr = (Elf64_Phdr *)bufp;
+ bufp += sizeof(Elf64_Phdr);
+ phdr->p_type = cpu_to_be32(PT_NOTE);
+ phdr->p_flags = 0;
+ phdr->p_align = 0;
+ phdr->p_paddr = phdr->p_vaddr = 0;
+ phdr->p_offset = cpu_to_be64(hdr_size);
+ phdr->p_filesz = phdr->p_memsz =
+ cpu_to_be64(oc_conf->cpu_notes_buf_size);
+ count++;
+
+ opalcore_off = opalcorebuf_sz;
+ ptload_phdr = (Elf64_Phdr *)bufp;
+ ptload_cnt = oc_conf->ptload_cnt;
+ paddr = 0;
+ for (i = 0; i < ptload_cnt; i++) {
+ phdr = (Elf64_Phdr *)bufp;
+ bufp += sizeof(Elf64_Phdr);
+ phdr->p_type = cpu_to_be32(PT_LOAD);
+ phdr->p_flags = cpu_to_be32(PF_R|PF_W|PF_X);
+ phdr->p_align = 0;
+ phdr->p_paddr = paddr;
+ phdr->p_vaddr =
+ cpu_to_be64((Elf64_Addr)__va(oc_conf->ptload_addr[i]));
+ phdr->p_filesz = phdr->p_memsz =
+ cpu_to_be64(oc_conf->ptload_size[i]);
+ phdr->p_offset = cpu_to_be64(opalcore_off);
+
+ count++;
+ opalcore_off += oc_conf->ptload_size[i];
+ paddr += oc_conf->ptload_size[i];
+ }
+
+ elf->e_phnum = cpu_to_be16(count);
+
+ for (i = 0; i < oc_conf->nr_threads; i++) {
+ bufp = (char *)regs_to_elf64_notes((Elf64_Word *)bufp,
+ &(oc_conf->regs[i]));
+ }
+ final_elf64_note((Elf64_Word *)bufp);
+
+ opalcore_size = opalcore_off;
+ return 0;
+}
+
+/* Init function for opalcore module. */
+static int __init opalcore_init(void)
+{
+ int rc = 0;
+
+ /*
+ * If opalcorebuf= is set in the 2nd kernel,
+ * then capture the dump.
+ */
+ if (!(is_opalcore_usable()))
+ return rc;
+
+ proc_opalcore = proc_create("opalcore", 0400, NULL,
+ &proc_opalcore_operations);
+ if (proc_opalcore)
+ proc_set_size(proc_opalcore, opalcore_size);
+ return 0;
+}
+fs_initcall(opalcore_init);
+
+/* Cleanup function for opalcore module. */
+void opalcore_cleanup(void)
+{
+ unsigned long order, count, i;
+ struct page *page;
+
+ if (proc_opalcore) {
+ proc_remove(proc_opalcore);
+ proc_opalcore = NULL;
+ }
+
+ ptload_phdr = NULL;
+ ptload_cnt = 0;
+
+ /* free core buffer */
+ order = get_order(opalcorebuf_sz);
+ count = 1 << order;
+ page = virt_to_page(opalcorebuf);
+ for (i = 0; i < count; i++)
+ ClearPageReserved(page + i);
+ __free_pages(page, order);
+}
diff --git a/arch/powerpc/platforms/powernv/opalcore.h
b/arch/powerpc/platforms/powernv/opalcore.h
new file mode 100644
index 0000000..b791a54
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opalcore.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2018, IBM Corporation
+ * Author: Hari Bathini <hbath...@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _OPALCORE_H
+#define _OPALCORE_H
+
+#define MAX_PT_LOAD_CNT 16
+
+struct opalcore_config {
+ unsigned long cpu_notes_buf_size;
+ unsigned long ptload_cnt;
+ unsigned long ptload_addr[MAX_PT_LOAD_CNT];
+ unsigned long ptload_size[MAX_PT_LOAD_CNT];
+ unsigned int nr_threads;
+ struct pt_regs regs[NR_CPUS];
+};
+
+extern int create_opalcore(struct opalcore_config *opalcore_config);
+extern void opalcore_cleanup(void);
+
+#endif /* _OPALCORE_H */
diff --git a/arch/powerpc/platforms/powernv/powernv_fadump.c
b/arch/powerpc/platforms/powernv/powernv_fadump.c
index 36f0360..fd95bbb 100644
--- a/arch/powerpc/platforms/powernv/powernv_fadump.c
+++ b/arch/powerpc/platforms/powernv/powernv_fadump.c
@@ -26,8 +26,10 @@
#include "../../kernel/fadump_internal.h"
#include "powernv_fadump.h"
+#include "opalcore.h"
static struct powernv_fadump_mem_struct fdm;
+static struct opalcore_config oc_config;
static const struct powernv_fadump_mem_struct *fdm_active;
unsigned long fdm_actual_size;
@@ -200,6 +202,8 @@ static int powernv_invalidate_fadump(struct fw_dump
*fadump_conf)
{
int rc;
+ opalcore_cleanup();
+
rc = opal_configure_fadump(FADUMP_INVALIDATE, (void *)fdm_active,
fdm_actual_size);
if (rc) {
@@ -230,15 +234,19 @@ static inline int fadump_get_logical_cpu(struct
fadump_backup_area *ba, u32 pir)
static struct fadump_reg_entry*
fadump_read_registers(unsigned int regs_per_thread,
struct fadump_reg_entry *reg_entry,
- struct pt_regs *regs)
+ struct pt_regs *regs, bool opal_data)
{
int i;
+ u64 reg_value;
memset(regs, 0, sizeof(struct pt_regs));
for (i = 0; i < regs_per_thread; i++) {
+ reg_value = (opal_data ? reg_entry->reg_value :
+ be64_to_cpu(reg_entry->reg_value));
+
fadump_set_regval(regs, be64_to_cpu(reg_entry->reg_id),
- be64_to_cpu(reg_entry->reg_value));
+ reg_value);
reg_entry++;
}
return reg_entry;
@@ -330,16 +338,23 @@ static int __init fadump_build_cpu_notes(struct fw_dump
*fadump_conf)
regs = fdh->regs;
note_buf = fadump_regs_to_elf_notes(note_buf,
®s);
+ fadump_read_registers(regs_per_thread,
+ reg_entry,
+ &oc_config.regs[cpu],
+ true);
continue;
}
}
reg_entry = (struct fadump_reg_entry *)(bufp +
CPU_REG_ENTRY_OFFSET);
- fadump_read_registers(regs_per_thread, reg_entry, ®s);
+ fadump_read_registers(regs_per_thread, reg_entry, ®s, false);
note_buf = fadump_regs_to_elf_notes(note_buf, ®s);
+ fadump_read_registers(regs_per_thread, reg_entry,
+ &oc_config.regs[cpu], true);
}
final_note(note_buf);
+ oc_config.nr_threads = num_cpus;
if (fdh) {
pr_debug("Updating elfcore header (%llx) with cpu notes\n",
@@ -361,7 +376,7 @@ static int __init fadump_build_cpu_notes(struct fw_dump
*fadump_conf)
static int __init powernv_process_fadump(struct fw_dump *fadump_conf)
{
struct fadump_crash_info_header *fdh;
- int rc = 0;
+ int i, rc = 0;
if (!fdm_active || !fadump_conf->fadumphdr_addr)
return -EINVAL;
@@ -384,7 +399,34 @@ static int __init powernv_process_fadump(struct fw_dump
*fadump_conf)
*/
elfcorehdr_addr = fdh->elfcorehdr_addr;
- return rc;
+ /*
+ * pt_regs for opalcore are populated while build cpu notes
+ * for vmcore. Populate other config info to facilitate
+ * exporting /proc/opalcore file.
+ */
+ oc_config.cpu_notes_buf_size = fadump_conf->cpu_notes_buf_size;
+ oc_config.ptload_cnt = 0;
+ for(i = 0; i < be16_to_cpu(fdm_active->section_count); i++) {
+ u8 src_type = fdm_active->section[i].src_type;
+
+ if ((src_type < POWERNV_FADUMP_OPAL_REGION) ||
+ (src_type >= POWERNV_FADUMP_FW_REGION))
+ continue;
+
+ if (oc_config.ptload_cnt >= MAX_PT_LOAD_CNT)
+ break;
+
+ oc_config.ptload_addr[oc_config.ptload_cnt] =
+ be64_to_cpu(fdm_active->section[i].dest_addr);
+ oc_config.ptload_size[oc_config.ptload_cnt++] =
+ be64_to_cpu(fdm_active->section[i].dest_size);
+ }
+
+ rc = create_opalcore(&oc_config);
+ if (rc)
+ pr_warn("Could not create opalcore ELF file\n");
+
+ return 0;
}
static void powernv_fadump_region_show(struct fw_dump *fadump_conf,
