7:02 a.m.
This patch adds ARM support for kdump files (ELF files readable from
/proc/vmcore). It also provides a function which tries to determine correct
phys_base based on the program headers in the ELF file.
Signed-off-by: Jan Karlsson <jan.karlsson(a)sonyericsson.com>
Signed-off-by: Thomas Fänge <thomas.fange(a)sonyericsson.com>
Signed-off-by: Mika Westerberg <ext-mika.1.westerberg(a)nokia.com>
---
defs.h | 3 ++
netdump.c | 115 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 118 insertions(+), 0 deletions(-)
diff --git a/defs.h b/defs.h
index 3d34b8e..c8bae00 100755
--- a/defs.h
+++ b/defs.h
@@ -4353,6 +4353,9 @@ int xen_minor_version(void);
int get_netdump_arch(void);
void *get_regs_from_elf_notes(struct task_context *);
void map_cpus_to_prstatus(void);
+#ifdef ARM
+int kdump_phys_base(ulong *);
+#endif
/*
* diskdump.c
diff --git a/netdump.c b/netdump.c
index 3a5db13..3bf6e3b 100644
--- a/netdump.c
+++ b/netdump.c
@@ -32,6 +32,7 @@ static void dump_Elf64_Ehdr(Elf64_Ehdr *);
static void dump_Elf64_Phdr(Elf64_Phdr *, int);
static size_t dump_Elf64_Nhdr(Elf64_Off offset, int);
static void get_netdump_regs_ppc64(struct bt_info *, ulong *, ulong *);
+static void get_netdump_regs_arm(struct bt_info *, ulong *, ulong *);
static physaddr_t xen_kdump_p2m(physaddr_t);
static void check_dumpfile_size(char *);
@@ -170,6 +171,12 @@ is_netdump(char *file, ulong source_query)
goto bailout;
break;
+ case EM_ARM:
+ if (machine_type_mismatch(file, "ARM", NULL,
+ source_query))
+ goto bailout;
+ break;
+
default:
if (machine_type_mismatch(file, "(unknown)", NULL,
source_query))
@@ -2094,6 +2101,10 @@ get_netdump_regs(struct bt_info *bt, ulong *eip, ulong *esp)
case EM_S390:
machdep->get_stack_frame(bt, eip, esp);
break;
+
+ case EM_ARM:
+ return get_netdump_regs_arm(bt, eip, esp);
+ break;
default:
error(FATAL,
"support for ELF machine type %d not available\n",
@@ -2393,6 +2404,40 @@ get_netdump_regs_ppc64(struct bt_info *bt, ulong *eip, ulong *esp)
machdep->get_stack_frame(bt, eip, esp);
}
+static void
+get_netdump_regs_arm(struct bt_info *bt, ulong *eip, ulong *esp)
+{
+ Elf64_Nhdr *note;
+ size_t len;
+
+ if ((bt->task == tt->panic_task) ||
+ (is_task_active(bt->task) && nd->num_prstatus_notes > 1)) {
+ /*
+ * Registers are saved during the dump process for the
+ * panic task. Whereas in kdump, regs are captured for all
+ * CPUs if they responded to an IPI.
+ */
+ if (nd->num_prstatus_notes > 1) {
+ if (!nd->nt_prstatus_percpu[bt->tc->processor])
+ error(FATAL,
+ "cannot determine NT_PRSTATUS ELF note "
+ "for %s task: %lx\n",
+ (bt->task == tt->panic_task) ?
+ "panic" : "active", bt->task);
+ note = (Elf64_Nhdr *)
+ nd->nt_prstatus_percpu[bt->tc->processor];
+ } else
+ note = (Elf64_Nhdr *)nd->nt_prstatus;
+
+ len = sizeof(Elf64_Nhdr);
+ len = roundup(len + note->n_namesz, 4);
+ bt->machdep = (void *)((char *)note + len +
+ MEMBER_OFFSET("elf_prstatus", "pr_reg"));
+ }
+
+ machdep->get_stack_frame(bt, eip, esp);
+}
+
int
is_partial_netdump(void)
{
@@ -2644,6 +2689,7 @@ xen_minor_version(void)
static void *get_ppc64_regs_from_elf_notes(struct task_context *);
static void *get_x86_regs_from_elf_notes(struct task_context *);
static void *get_x86_64_regs_from_elf_notes(struct task_context *);
+static void *get_arm_regs_from_elf_notes(struct task_context *);
int get_netdump_arch(void)
{
@@ -2670,6 +2716,8 @@ get_regs_from_elf_notes(struct task_context *tc)
return get_ppc64_regs_from_elf_notes(tc);
case EM_X86_64:
return get_x86_64_regs_from_elf_notes(tc);
+ case EM_ARM:
+ return get_arm_regs_from_elf_notes(tc);
default:
error(FATAL,
"support for ELF machine type %d not available\n",
@@ -2786,3 +2834,70 @@ get_ppc64_regs_from_elf_notes(struct task_context *tc)
return pt_regs;
}
+
+#ifdef ARM
+/*
+ * In case of ARM we need to determine correct PHYS_OFFSET from the kdump file.
+ * This is done by taking lowest physical address (LMA) from given load
+ * segments. Normally this is the right one.
+ *
+ * Alternative would be to store phys_base in VMCOREINFO but current kernel
+ * kdump doesn't do that yet.
+ */
+int kdump_phys_base(ulong *phys_base)
+{
+ struct pt_load_segment *pls;
+ ulong paddr = ULONG_MAX;
+ int i;
+
+ for (i = 0; i < nd->num_pt_load_segments; i++) {
+ pls = &nd->pt_load_segments[i];
+ if (pls->phys_start < paddr)
+ paddr = pls->phys_start;
+ }
+
+ if (paddr != ULONG_MAX) {
+ *phys_base = paddr;
+ return TRUE;
+ }
+ return FALSE;
+}
+#endif /* ARM */
+
+static void *
+get_arm_regs_from_elf_notes(struct task_context *tc)
+{
+ Elf32_Nhdr *note_32;
+ Elf64_Nhdr *note_64;
+ void *note;
+ size_t len;
+ void *pt_regs;
+
+ len = 0;
+ pt_regs = NULL;
+
+ if ((tc->task == tt->panic_task) ||
+ (is_task_active(tc->task) && (nd->num_prstatus_notes > 1))) {
+ if (nd->num_prstatus_notes > 1)
+ note = (void *)
+ nd->nt_prstatus_percpu[tc->processor];
+ else
+ note = (void *)nd->nt_prstatus;
+ if (nd->elf32) {
+ note_32 = (Elf32_Nhdr *)note;
+ len = sizeof(Elf32_Nhdr);
+ len = roundup(len + note_32->n_namesz, 4);
+ } else if (nd->elf64) {
+ note_64 = (Elf64_Nhdr *)note;
+ len = sizeof(Elf64_Nhdr);
+ len = roundup(len + note_64->n_namesz, 4);
+ }
+
+ pt_regs = (void *)((char *)note + len +
+ MEMBER_OFFSET("elf_prstatus", "pr_reg"));
+ } else
+ error(FATAL,
+ "cannot determine arm register set for task \"%s\"\n",
+ tc->comm);
+ return pt_regs;
+}
--
1.5.6.5