From 51e17d89d7c9bd0ed77eeff9b3ed4509b9213a24 Mon Sep 17 00:00:00 2001
From: Dave Anderson <anderson@redhat.com>
Date: Thu, 13 Nov 2014 14:40:54 -0500
Subject: [PATCH] Fix for the support of compressed kdump clones created with
the KVM "virsh dump --memory-only --format <compression-type>" command, where
the compression-type is either "kdump-zlib", "kdump-lzo" or "kdump-snappy".
Without the patch, if an x86_64 guest kernel was loaded with a non-zero
"phys_base", the "--machdep phys_base=<offset>" command line option was
required as a workaround or the crash session would fail with the warning
message "WARNING: cannot read linux_banner string" followed by the fatal
error message "crash: vmlinux and <dumpfile name> do not match!".
(anderson@redhat.com)
---
defs.h | 3 ++-
diskdump.c | 8 ++++++--
help.c | 2 +-
main.c | 6 ++++--
netdump.c | 8 ++++----
task.c | 2 +-
x86_64.c | 8 +++++++-
7 files changed, 25 insertions(+), 12 deletions(-)
diff --git a/defs.h b/defs.h
index 049da4e..2e52bc4 100644
--- a/defs.h
+++ b/defs.h
@@ -499,7 +499,7 @@ struct program_context {
#define FLAT_FORMAT() (pc->flags2 & FLAT)
#define ELF_NOTES_VALID() (pc->flags2 & ELF_NOTES)
#define RADIX_OVERRIDE (0x80ULL)
-#define QEMU_MEM_DUMP (0x100ULL)
+#define QEMU_MEM_DUMP_ELF (0x100ULL)
#define GET_LOG (0x200ULL)
#define VMCOREINFO (0x400ULL)
#define ALLOW_FP (0x800ULL)
@@ -509,6 +509,7 @@ struct program_context {
#define OFFLINE_HIDE (0x4000ULL)
#define INCOMPLETE_DUMP (0x8000ULL)
#define is_incomplete_dump() (pc->flags2 & INCOMPLETE_DUMP)
+#define QEMU_MEM_DUMP_COMPRESSED (0x10000ULL)
char *cleanup;
char *namelist_orig;
char *namelist_debug_orig;
diff --git a/diskdump.c b/diskdump.c
index 603c325..3d33fdc 100644
--- a/diskdump.c
+++ b/diskdump.c
@@ -249,11 +249,13 @@ process_elf32_notes(void *note_buf, unsigned long size_note)
for (index = 0; index < size_note; index += len) {
nt = note_buf + index;
- if(nt->n_type == NT_PRSTATUS) {
+ if (nt->n_type == NT_PRSTATUS) {
dd->nt_prstatus_percpu[num] = nt;
num++;
}
len = sizeof(Elf32_Nhdr);
+ if (STRNEQ((char *)nt + len, "QEMU"))
+ pc->flags2 |= QEMU_MEM_DUMP_COMPRESSED;
len = roundup(len + nt->n_namesz, 4);
len = roundup(len + nt->n_descsz, 4);
}
@@ -275,11 +277,13 @@ process_elf64_notes(void *note_buf, unsigned long size_note)
for (index = 0; index < size_note; index += len) {
nt = note_buf + index;
- if(nt->n_type == NT_PRSTATUS) {
+ if (nt->n_type == NT_PRSTATUS) {
dd->nt_prstatus_percpu[num] = nt;
num++;
}
len = sizeof(Elf64_Nhdr);
+ if (STRNEQ((char *)nt + len, "QEMU"))
+ pc->flags2 |= QEMU_MEM_DUMP_COMPRESSED;
len = roundup(len + nt->n_namesz, 4);
len = roundup(len + nt->n_descsz, 4);
}
diff --git a/help.c b/help.c
index 48e6de6..6aa3e20 100644
--- a/help.c
+++ b/help.c
@@ -688,7 +688,7 @@ cmd_help(void)
static void
dump_registers(void)
{
- if (pc->flags2 & QEMU_MEM_DUMP) {
+ if (pc->flags2 & QEMU_MEM_DUMP_ELF) {
dump_registers_for_qemu_mem_dump();
return;
} else if (DISKDUMP_DUMPFILE()) {
diff --git a/main.c b/main.c
index cd8c37e..d16ef12 100644
--- a/main.c
+++ b/main.c
@@ -1401,8 +1401,10 @@ dump_program_context(void)
fprintf(fp, "%sLIVE_DUMP", others++ ? "|" : "");
if (pc->flags2 & RADIX_OVERRIDE)
fprintf(fp, "%sRADIX_OVERRIDE", others++ ? "|" : "");
- if (pc->flags2 & QEMU_MEM_DUMP)
- fprintf(fp, "%sQEMU_MEM_DUMP", others++ ? "|" : "");
+ if (pc->flags2 & QEMU_MEM_DUMP_ELF)
+ fprintf(fp, "%sQEMU_MEM_DUMP_ELF", others++ ? "|" : "");
+ if (pc->flags2 & QEMU_MEM_DUMP_COMPRESSED)
+ fprintf(fp, "%sQEMU_MEM_DUMP_COMPRESSED", others++ ? "|" : "");
if (pc->flags2 & GET_LOG)
fprintf(fp, "%sGET_LOG", others++ ? "|" : "");
if (pc->flags2 & VMCOREINFO)
diff --git a/netdump.c b/netdump.c
index 726c3f1..903faa0 100644
--- a/netdump.c
+++ b/netdump.c
@@ -1883,7 +1883,7 @@ dump_Elf32_Nhdr(Elf32_Off offset, int store)
netdump_print("(?)\n");
if (qemuinfo)
- pc->flags2 |= QEMU_MEM_DUMP;
+ pc->flags2 |= QEMU_MEM_DUMP_ELF;
break;
case NT_XEN_KDUMP_CR3:
@@ -2163,7 +2163,7 @@ dump_Elf64_Nhdr(Elf64_Off offset, int store)
netdump_print("(?)\n");
if (qemuinfo)
- pc->flags2 |= QEMU_MEM_DUMP;
+ pc->flags2 |= QEMU_MEM_DUMP_ELF;
break;
case NT_XEN_KDUMP_CR3:
@@ -3939,7 +3939,7 @@ kdump_backup_region_init(void)
sd = get_sadump_data();
is_32_bit = FALSE;
sprintf(typename, "sadump");
- } else if (pc->flags2 & QEMU_MEM_DUMP) {
+ } else if (pc->flags2 & QEMU_MEM_DUMP_ELF) {
vd = get_kdump_vmcore_data();
if (vd->flags & KDUMP_ELF32)
is_32_bit = TRUE;
@@ -4122,7 +4122,7 @@ kdump_backup_region_init(void)
sd->backup_src_start = backup_src_start;
sd->backup_src_size = backup_src_size;
sd->backup_offset = backup_offset;
- } else if (pc->flags2 & QEMU_MEM_DUMP) {
+ } else if (pc->flags2 & QEMU_MEM_DUMP_ELF) {
vd->flags |= QEMU_MEM_DUMP_KDUMP_BACKUP;
vd->backup_src_start = backup_src_start;
vd->backup_src_size = backup_src_size;
diff --git a/task.c b/task.c
index fe45921..f5bbe64 100644
--- a/task.c
+++ b/task.c
@@ -483,7 +483,7 @@ task_init(void)
tt->this_task = pid_to_task(active_pid);
}
else {
- if (KDUMP_DUMPFILE() && !(pc->flags2 & QEMU_MEM_DUMP))
+ if (KDUMP_DUMPFILE() && !(pc->flags2 & QEMU_MEM_DUMP_ELF))
map_cpus_to_prstatus();
else if (ELF_NOTES_VALID() && DISKDUMP_DUMPFILE())
map_cpus_to_prstatus_kdump_cmprs();
diff --git a/x86_64.c b/x86_64.c
index 03adc85..bbf1326 100644
--- a/x86_64.c
+++ b/x86_64.c
@@ -6039,6 +6039,12 @@ x86_64_calc_phys_base(void)
if (DISKDUMP_DUMPFILE()) {
if (diskdump_phys_base(&phys_base)) {
machdep->machspec->phys_base = phys_base;
+ if ((pc->flags2 & QEMU_MEM_DUMP_COMPRESSED) &&
+ !x86_64_virt_phys_base())
+ error(WARNING,
+ "cannot determine physical base address:"
+ " defaulting to %lx\n\n",
+ machdep->machspec->phys_base);
if (CRASHDEBUG(1))
fprintf(fp, "compressed kdump: phys_base: %lx\n",
phys_base);
@@ -6099,7 +6105,7 @@ x86_64_calc_phys_base(void)
}
}
- if ((pc->flags2 & QEMU_MEM_DUMP) && !x86_64_virt_phys_base())
+ if ((pc->flags2 & QEMU_MEM_DUMP_ELF) && !x86_64_virt_phys_base())
error(WARNING,
"cannot determine physical base address:"
" defaulting to %lx\n\n",