See docs/specs/fw_cfg.txt for details.
The "etc/vmcoreinfo" is added when using "-global
fw_cfg.vmcoreinfo=on" qemu option.
Disabled by default for machine types v2.9 and older.
Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
include/hw/compat.h | 8 ++++++++
include/hw/nvram/fw_cfg.h | 9 +++++++++
hw/nvram/fw_cfg.c | 20 ++++++++++++++++++++
docs/specs/fw_cfg.txt | 16 ++++++++++++++++
4 files changed, 53 insertions(+)
diff --git a/include/hw/compat.h b/include/hw/compat.h
index 08f36004da..317fd2e2e3 100644
--- a/include/hw/compat.h
+++ b/include/hw/compat.h
@@ -18,6 +18,14 @@
.driver = "pcie-root-port",\
.property = "x-migrate-msix",\
.value = "false",\
+ },{\
+ .driver = "fw_cfg_mem",\
+ .property = "vmcoreinfo",\
+ .value = "off",\
+ },{\
+ .driver = "fw_cfg_io",\
+ .property = "vmcoreinfo",\
+ .value = "off",\
},
#define HW_COMPAT_2_8 \
diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
index 3527cd51d8..a35f47405d 100644
--- a/include/hw/nvram/fw_cfg.h
+++ b/include/hw/nvram/fw_cfg.h
@@ -30,6 +30,11 @@ typedef struct FWCfgFile {
void fw_cfg_set_order_override(FWCfgState *fw_cfg, int order);
void fw_cfg_reset_order_override(FWCfgState *fw_cfg);
+typedef struct FWCfgVMCoreInfo {
+ uint64_t paddr;
+ uint32_t size;
+} QEMU_PACKED FWCfgVMCoreInfo;
+
typedef struct FWCfgFiles {
uint32_t count;
FWCfgFile f[];
@@ -65,6 +70,10 @@ struct FWCfgState {
dma_addr_t dma_addr;
AddressSpace *dma_as;
MemoryRegion dma_iomem;
+
+ bool vmcoreinfo_enabled;
+ bool has_vmcoreinfo;
+ FWCfgVMCoreInfo vmcoreinfo;
};
struct FWCfgIoState {
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 28780088b9..342afc4ed2 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -504,6 +504,7 @@ static void fw_cfg_reset(DeviceState *d)
/* we never register a read callback for FW_CFG_SIGNATURE */
fw_cfg_select(s, FW_CFG_SIGNATURE);
+ s->has_vmcoreinfo = false;
}
/* Save restore 32 bit int as uint16_t
@@ -869,7 +870,12 @@ static void fw_cfg_machine_ready(struct Notifier *n, void
*data)
qemu_register_reset(fw_cfg_machine_reset, s);
}
+static void fw_cfg_vmci_written(void *dev)
+{
+ FWCfgState *s = FW_CFG(dev);
+ s->has_vmcoreinfo = true;
+}
static void fw_cfg_common_realize(DeviceState *dev, Error **errp)
{
@@ -895,6 +901,16 @@ static void fw_cfg_common_realize(DeviceState *dev, Error
**errp)
fw_cfg_add_i32(s, FW_CFG_ID, version);
+ if (s->vmcoreinfo_enabled) {
+ if (!s->dma_enabled) {
+ error_setg(errp, "vmcoreinfo requires dma_enabled");
+ return;
+ }
+ fw_cfg_add_file_callback(s, "etc/vmcoreinfo",
+ NULL, fw_cfg_vmci_written, s,
+ &s->vmcoreinfo, sizeof(s->vmcoreinfo), false);
+ }
+
s->machine_ready.notify = fw_cfg_machine_ready;
qemu_add_machine_init_done_notifier(&s->machine_ready);
}
@@ -1031,6 +1047,8 @@ static void fw_cfg_file_slots_allocate(FWCfgState *s,
Error **errp)
static Property fw_cfg_io_properties[] = {
DEFINE_PROP_BOOL("dma_enabled", FWCfgIoState, parent_obj.dma_enabled,
true),
+ DEFINE_PROP_BOOL("vmcoreinfo", FWCfgIoState, parent_obj.vmcoreinfo_enabled,
+ true),
DEFINE_PROP_UINT16("x-file-slots", FWCfgIoState, parent_obj.file_slots,
FW_CFG_FILE_SLOTS_DFLT),
DEFINE_PROP_END_OF_LIST(),
@@ -1082,6 +1100,8 @@ static Property fw_cfg_mem_properties[] = {
DEFINE_PROP_UINT32("data_width", FWCfgMemState, data_width, -1),
DEFINE_PROP_BOOL("dma_enabled", FWCfgMemState, parent_obj.dma_enabled,
true),
+ DEFINE_PROP_BOOL("vmcoreinfo", FWCfgMemState,
parent_obj.vmcoreinfo_enabled,
+ true),
DEFINE_PROP_UINT16("x-file-slots", FWCfgMemState, parent_obj.file_slots,
FW_CFG_FILE_SLOTS_DFLT),
DEFINE_PROP_END_OF_LIST(),
diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt
index 08c00bdf44..37d0f9f40a 100644
--- a/docs/specs/fw_cfg.txt
+++ b/docs/specs/fw_cfg.txt
@@ -136,6 +136,22 @@ struct FWCfgFile { /* an individual file entry, 64
bytes total */
char name[56]; /* fw_cfg item name, NUL-terminated ascii */
};
+=== etc/vmcoreinfo ===
+
+A guest may use this entry to add information details to qemu
+dumps. The entry gives location and size of an ELF note that is
+appended in qemu dumps.
+
+The entry is of 12 bytes with this format:
+
+struct FWCfgVMCoreInfo {
+ uint64_t paddr; /* physical address of ELF note, LE */
+ uint32_t size; /* size of ELF note region, LE */
+};
+
+The note format/class must be of the target bitness and the size must
+be less than 1Mb.
+
=== All Other Data Items ===
Please consult the QEMU source for the most up-to-date and authoritative list
--
2.14.0.1.geff633fa0
