From: Namhyung Kim <namhyung@xxxxxxxxx>
Add virtio pstore device to allow kernel log files saved on the host.
It will save the log files on the directory given by pstore device
option.
$ qemu-system-x86_64 -device virtio-pstore,directory=dir-xx ...
(guest) # echo c > /proc/sysrq-trigger
$ ls dir-xx
dmesg-0.enc.z dmesg-1.enc.z
The log files are usually compressed using zlib. Users can see the log
messages directly on the host or on the guest (using pstore filesystem).
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Anthony Liguori <aliguori@xxxxxxxxxx>
Cc: Anton Vorontsov <anton@xxxxxxxxxx>
Cc: Colin Cross <ccross@xxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
Cc: qemu-devel@xxxxxxxxxx
Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxx>
---
hw/virtio/Makefile.objs | 2 +-
hw/virtio/virtio-pci.c | 50 ++++
hw/virtio/virtio-pci.h | 14 +
hw/virtio/virtio-pstore.c | 328 +++++++++++++++++++++
include/hw/pci/pci.h | 1 +
include/hw/virtio/virtio-pstore.h | 30 ++
include/standard-headers/linux/virtio_ids.h | 1 +
.../linux/{virtio_ids.h => virtio_pstore.h} | 48 +--
qdev-monitor.c | 1 +
9 files changed, 455 insertions(+), 20 deletions(-)
create mode 100644 hw/virtio/virtio-pstore.c
create mode 100644 include/hw/virtio/virtio-pstore.h
copy include/standard-headers/linux/{virtio_ids.h => virtio_pstore.h} (63%)
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 3e2b175..aae7082 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -4,4 +4,4 @@ common-obj-y += virtio-bus.o
common-obj-y += virtio-mmio.o
obj-y += virtio.o virtio-balloon.o
-obj-$(CONFIG_LINUX) += vhost.o vhost-backend.o vhost-user.o
+obj-$(CONFIG_LINUX) += vhost.o vhost-backend.o vhost-user.o virtio-pstore.o
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 2b34b43..8281b80 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -2416,6 +2416,55 @@ static const TypeInfo virtio_host_pci_info = {
};
#endif
+/* virtio-pstore-pci */
+
+static void virtio_pstore_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+ VirtIOPstorePCI *vps = VIRTIO_PSTORE_PCI(vpci_dev);
+ DeviceState *vdev = DEVICE(&vps->vdev);
+ Error *err = NULL;
+
+ qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus));
+ object_property_set_bool(OBJECT(vdev), true, "realized", &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+}
+
+static void virtio_pstore_pci_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass);
+ PCIDeviceClass *pcidev_k = PCI_DEVICE_CLASS(klass);
+
+ k->realize = virtio_pstore_pci_realize;
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+
+ pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+ pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_PSTORE;
+ pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
+ pcidev_k->class_id = PCI_CLASS_OTHERS;
+}
+
+static void virtio_pstore_pci_instance_init(Object *obj)
+{
+ VirtIOPstorePCI *dev = VIRTIO_PSTORE_PCI(obj);
+
+ virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+ TYPE_VIRTIO_PSTORE);
+ object_property_add_alias(obj, "directory", OBJECT(&dev->vdev),
+ "directory", &error_abort);
+}
+
+static const TypeInfo virtio_pstore_pci_info = {
+ .name = TYPE_VIRTIO_PSTORE_PCI,
+ .parent = TYPE_VIRTIO_PCI,
+ .instance_size = sizeof(VirtIOPstorePCI),
+ .instance_init = virtio_pstore_pci_instance_init,
+ .class_init = virtio_pstore_pci_class_init,
+};
+
/* virtio-pci-bus */
static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size,
@@ -2485,6 +2534,7 @@ static void virtio_pci_register_types(void)
#ifdef CONFIG_VHOST_SCSI
type_register_static(&vhost_scsi_pci_info);
#endif
+ type_register_static(&virtio_pstore_pci_info);
}
type_init(virtio_pci_register_types)
diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index e4548c2..b4c039f 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -31,6 +31,7 @@
#ifdef CONFIG_VHOST_SCSI
#include "hw/virtio/vhost-scsi.h"
#endif
+#include "hw/virtio/virtio-pstore.h"
typedef struct VirtIOPCIProxy VirtIOPCIProxy;
typedef struct VirtIOBlkPCI VirtIOBlkPCI;
@@ -44,6 +45,7 @@ typedef struct VirtIOInputPCI VirtIOInputPCI;
typedef struct VirtIOInputHIDPCI VirtIOInputHIDPCI;
typedef struct VirtIOInputHostPCI VirtIOInputHostPCI;
typedef struct VirtIOGPUPCI VirtIOGPUPCI;
+typedef struct VirtIOPstorePCI VirtIOPstorePCI;
/* virtio-pci-bus */
@@ -311,6 +313,18 @@ struct VirtIOGPUPCI {
VirtIOGPU vdev;
};
+/*
+ * virtio-pstore-pci: This extends VirtioPCIProxy.
+ */
+#define TYPE_VIRTIO_PSTORE_PCI "virtio-pstore-pci"
+#define VIRTIO_PSTORE_PCI(obj) \
+ OBJECT_CHECK(VirtIOPstorePCI, (obj), TYPE_VIRTIO_PSTORE_PCI)
+
+struct VirtIOPstorePCI {
+ VirtIOPCIProxy parent_obj;
+ VirtIOPstore vdev;
+};
+
/* Virtio ABI version, if we increment this, we break the guest driver. */
#define VIRTIO_PCI_ABI_VERSION 0
diff --git a/hw/virtio/virtio-pstore.c b/hw/virtio/virtio-pstore.c
new file mode 100644
index 0000000..98cee7f
--- /dev/null
+++ b/hw/virtio/virtio-pstore.c
@@ -0,0 +1,328 @@
+/*
+ * Virtio Pstore Device
+ *
+ * Copyright (C) 2016 LG Electronics
+ *
+ * Authors:
+ * Namhyung Kim <namhyung@xxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include <stdio.h>
+
+#include "qemu/osdep.h"
+#include "qemu/iov.h"
+#include "qemu-common.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "sysemu/kvm.h"
+#include "qapi/visitor.h"
+#include "qapi-event.h"
+#include "trace.h"
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/virtio-access.h"
+#include "hw/virtio/virtio-pstore.h"
+
+
+static void virtio_pstore_to_filename(VirtIOPstore *s, char *buf, size_t sz,
+ struct virtio_pstore_hdr *hdr)
+{
+ const char *basename;
+
+ switch (hdr->type) {
+ case VIRTIO_PSTORE_TYPE_DMESG:
+ basename = "dmesg";
+ break;
+ default:
+ basename = "unknown";
+ break;
+ }
+
+ snprintf(buf, sz, "%s/%s-%llu%s", s->directory, basename,
+ (unsigned long long) hdr->id,
+ hdr->flags & VIRTIO_PSTORE_FL_COMPRESSED ? ".enc.z" : "");
+}
+
+static void virtio_pstore_from_filename(VirtIOPstore *s, char *name,
+ char *buf, size_t sz,
+ struct virtio_pstore_hdr *hdr)
+{
+ size_t len = strlen(name);
+
+ hdr->flags = 0;
+ if (!strncmp(name + len - 6, ".enc.z", 6)) {
+ hdr->flags |= VIRTIO_PSTORE_FL_COMPRESSED;
+ }
+
+ snprintf(buf, sz, "%s/%s", s->directory, name);
+
+ if (!strncmp(name, "dmesg-", 6)) {
+ hdr->type = cpu_to_le16(VIRTIO_PSTORE_TYPE_DMESG);
+ name += 6;
+ } else if (!strncmp(name, "unknown-", 8)) {
+ hdr->type = cpu_to_le16(VIRTIO_PSTORE_TYPE_UNKNOWN);
+ name += 8;
+ }
+
+ qemu_strtoull(name, NULL, 0, &hdr->id);
+}
+
+static ssize_t virtio_pstore_do_open(VirtIOPstore *s)
+{
+ s->dir = opendir(s->directory);
+ if (s->dir == NULL) {
+ return -1;
+ }
+
+ return 0;
+}
+
+static ssize_t virtio_pstore_do_read(VirtIOPstore *s, void *buf, size_t sz,
+ struct virtio_pstore_hdr *hdr)
+{
+ char path[PATH_MAX];
+ FILE *fp;
+ ssize_t len;
+ struct stat stbuf;
+ struct dirent *dent;
+
+ if (s->dir == NULL) {
+ return -1;
+ }
+
+ dent = readdir(s->dir);
+ while (dent) {
+ if (dent->d_name[0] != '.') {
+ break;
+ }
+ dent = readdir(s->dir);
+ }
+
+ if (dent == NULL) {
+ return 0;
+ }
+
+ virtio_pstore_from_filename(s, dent->d_name, path, sizeof(path), hdr);
+ if (stat(path, &stbuf) < 0) {
+ return -1;
+ }
+
+ fp = fopen(path, "r");
+ if (fp == NULL) {
+ error_report("cannot open %s (%p %p)", path, s, s->directory);
+ return -1;
+ }
+
+ len = fread(buf, 1, sz, fp);
+ if (len < 0 && errno == EAGAIN) {
+ len = 0;
+ }
+
+ hdr->id = cpu_to_le64(hdr->id);
+ hdr->flags = cpu_to_le32(hdr->flags);
+ hdr->time_sec = cpu_to_le64(stbuf.st_ctim.tv_sec);
+ hdr->time_nsec = cpu_to_le32(stbuf.st_ctim.tv_nsec);
+
+ fclose(fp);
+ return len;
+}
+
+static ssize_t virtio_pstore_do_write(VirtIOPstore *s, void *buf, size_t sz,
+ struct virtio_pstore_hdr *hdr)
+{
+ char path[PATH_MAX];
+ FILE *fp;
+
+ virtio_pstore_to_filename(s, path, sizeof(path), hdr);
+
+ fp = fopen(path, "w");
+ if (fp == NULL) {
+ error_report("cannot open %s (%p %p)", path, s, s->directory);
+ return -1;
+ }
+ fwrite(buf, 1, sz, fp);
+ fclose(fp);
+
+ return sz;
+}
+
+static ssize_t virtio_pstore_do_close(VirtIOPstore *s)
+{
+ if (s->dir == NULL) {
+ return 0;
+ }
+
+ closedir(s->dir);
+ s->dir = NULL;
+
+ return 0;
+}
+
+static ssize_t virtio_pstore_do_erase(VirtIOPstore *s,
+ struct virtio_pstore_hdr *hdr)
+{
+ char path[PATH_MAX];
+
+ virtio_pstore_to_filename(s, path, sizeof(path), hdr);
+
+ return unlink(path);
+}
+
+static void virtio_pstore_handle_io(VirtIODevice *vdev, VirtQueue *vq)
+{
+ VirtIOPstore *s = VIRTIO_PSTORE(vdev);
+ VirtQueueElement *elem;
+ struct virtio_pstore_hdr *hdr;
+ ssize_t len;
+
+ for (;;) {
+ elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
+ if (!elem) {
+ return;
+ }
+
+ hdr = elem->out_sg[0].iov_base;
+ if (elem->out_sg[0].iov_len != sizeof(*hdr)) {
+ error_report("invalid header size: %u",
+ (unsigned)elem->out_sg[0].iov_len);
+ exit(1);
+ }
+
+ switch (hdr->cmd) {
+ case VIRTIO_PSTORE_CMD_OPEN:
+ len = virtio_pstore_do_open(s);
+ break;
+ case VIRTIO_PSTORE_CMD_READ:
+ len = virtio_pstore_do_read(s, elem->in_sg[0].iov_base,
+ elem->in_sg[0].iov_len, hdr);
+ break;
+ case VIRTIO_PSTORE_CMD_WRITE:
+ len = virtio_pstore_do_write(s, elem->out_sg[1].iov_base,
+ elem->out_sg[1].iov_len, hdr);
+ break;
+ case VIRTIO_PSTORE_CMD_CLOSE:
+ len = virtio_pstore_do_close(s);
+ break;
+ case VIRTIO_PSTORE_CMD_ERASE:
+ len = virtio_pstore_do_erase(s, hdr);
+ break;
+ default:
+ len = -1;
+ break;
+ }
+
+ if (len < 0) {
+ return;
+ }
+
+ virtqueue_push(vq, elem, len);
+
+ virtio_notify(vdev, vq);
+ g_free(elem);
+ }
+}
+
+static void virtio_pstore_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VirtIOPstore *s = VIRTIO_PSTORE(dev);
+
+ virtio_init(vdev, "virtio-pstore", VIRTIO_ID_PSTORE, 0);
+
+ s->vq = virtio_add_queue(vdev, 128, virtio_pstore_handle_io);
+}
+
+static void virtio_pstore_device_unrealize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+
+ virtio_cleanup(vdev);
+}
+
+static uint64_t get_features(VirtIODevice *vdev, uint64_t f, Error **errp)
+{
+ return f;
+}
+
+static void pstore_get_directory(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ VirtIOPstore *s = opaque;
+
+ visit_type_str(v, name, &s->directory, errp);
+}
+
+static void pstore_set_directory(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ VirtIOPstore *s = opaque;
+ Error *local_err = NULL;
+ char *value;
+
+ visit_type_str(v, name, &value, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ g_free(s->directory);
+ s->directory = strdup(value);
+
+ g_free(value);
+}
+
+static void pstore_release_directory(Object *obj, const char *name,
+ void *opaque)
+{
+ VirtIOPstore *s = opaque;
+
+ g_free(s->directory);
+ s->directory = NULL;
+}
+
+static Property virtio_pstore_properties[] = {
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_pstore_instance_init(Object *obj)
+{
+ VirtIOPstore *s = VIRTIO_PSTORE(obj);
+
+ object_property_add(obj, "directory", "str",
+ pstore_get_directory, pstore_set_directory,
+ pstore_release_directory, s, NULL);
+}
+
+static void virtio_pstore_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+ dc->props = virtio_pstore_properties;
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+ vdc->realize = virtio_pstore_device_realize;
+ vdc->unrealize = virtio_pstore_device_unrealize;
+ vdc->get_features = get_features;
+}
+
+static const TypeInfo virtio_pstore_info = {
+ .name = TYPE_VIRTIO_PSTORE,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VirtIOPstore),
+ .instance_init = virtio_pstore_instance_init,
+ .class_init = virtio_pstore_class_init,
+};
+
+static void virtio_register_types(void)
+{
+ type_register_static(&virtio_pstore_info);
+}
+
+type_init(virtio_register_types)
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index 9ed1624..5689c6f 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -79,6 +79,7 @@
#define PCI_DEVICE_ID_VIRTIO_SCSI 0x1004
#define PCI_DEVICE_ID_VIRTIO_RNG 0x1005
#define PCI_DEVICE_ID_VIRTIO_9P 0x1009
+#define PCI_DEVICE_ID_VIRTIO_PSTORE 0x100a
#define PCI_VENDOR_ID_REDHAT 0x1b36
#define PCI_DEVICE_ID_REDHAT_BRIDGE 0x0001
diff --git a/include/hw/virtio/virtio-pstore.h b/include/hw/virtio/virtio-pstore.h
new file mode 100644
index 0000000..74cd1f6
--- /dev/null
+++ b/include/hw/virtio/virtio-pstore.h
@@ -0,0 +1,30 @@
+/*
+ * Virtio Pstore Support
+ *
+ * Authors:
+ * Namhyung Kim <namhyung@xxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef _QEMU_VIRTIO_PSTORE_H
+#define _QEMU_VIRTIO_PSTORE_H
+
+#include "standard-headers/linux/virtio_pstore.h"
+#include "hw/virtio/virtio.h"
+#include "hw/pci/pci.h"
+
+#define TYPE_VIRTIO_PSTORE "virtio-pstore-device"
+#define VIRTIO_PSTORE(obj) \
+ OBJECT_CHECK(VirtIOPstore, (obj), TYPE_VIRTIO_PSTORE)
+
+typedef struct VirtIOPstore {
+ VirtIODevice parent_obj;
+ VirtQueue *vq;
+ char *directory;
+ DIR *dir;
+} VirtIOPstore;
+
+#endif
diff --git a/include/standard-headers/linux/virtio_ids.h b/include/standard-headers/linux/virtio_ids.h
index 77925f5..cba6322 100644
--- a/include/standard-headers/linux/virtio_ids.h
+++ b/include/standard-headers/linux/virtio_ids.h
@@ -41,5 +41,6 @@
#define VIRTIO_ID_CAIF 12 /* Virtio caif */
#define VIRTIO_ID_GPU 16 /* virtio GPU */
#define VIRTIO_ID_INPUT 18 /* virtio input */
+#define VIRTIO_ID_PSTORE 19 /* virtio pstore */
#endif /* _LINUX_VIRTIO_IDS_H */
diff --git a/include/standard-headers/linux/virtio_ids.h b/include/standard-headers/linux/virtio_pstore.h
similarity index 63%
copy from include/standard-headers/linux/virtio_ids.h
copy to include/standard-headers/linux/virtio_pstore.h
index 77925f5..1b89cad 100644
--- a/include/standard-headers/linux/virtio_ids.h
+++ b/include/standard-headers/linux/virtio_pstore.h
@@ -1,9 +1,6 @@
-#ifndef _LINUX_VIRTIO_IDS_H
-#define _LINUX_VIRTIO_IDS_H
-/*
- * Virtio IDs
- *
- * This header is BSD licensed so anyone can use the definitions to implement
+#ifndef _LINUX_VIRTIO_PSTORE_H
+#define _LINUX_VIRTIO_PSTORE_H
+/* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
*
* Redistribution and use in source and binary forms, with or without
@@ -28,18 +25,31 @@
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE. */
+#include "standard-headers/linux/types.h"
+#include "standard-headers/linux/virtio_types.h"
+#include "standard-headers/linux/virtio_ids.h"
+#include "standard-headers/linux/virtio_config.h"
+
+#define VIRTIO_PSTORE_TYPE_UNKNOWN 0
+#define VIRTIO_PSTORE_TYPE_DMESG 1
+
+#define VIRTIO_PSTORE_CMD_NULL 0
+#define VIRTIO_PSTORE_CMD_OPEN 1
+#define VIRTIO_PSTORE_CMD_READ 2
+#define VIRTIO_PSTORE_CMD_WRITE 3
+#define VIRTIO_PSTORE_CMD_ERASE 4
+#define VIRTIO_PSTORE_CMD_CLOSE 5
+
+#define VIRTIO_PSTORE_FL_COMPRESSED 1
-#define VIRTIO_ID_NET 1 /* virtio net */
-#define VIRTIO_ID_BLOCK 2 /* virtio block */
-#define VIRTIO_ID_CONSOLE 3 /* virtio console */
-#define VIRTIO_ID_RNG 4 /* virtio rng */
-#define VIRTIO_ID_BALLOON 5 /* virtio balloon */
-#define VIRTIO_ID_RPMSG 7 /* virtio remote processor messaging */
-#define VIRTIO_ID_SCSI 8 /* virtio scsi */
-#define VIRTIO_ID_9P 9 /* 9p virtio console */
-#define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */
-#define VIRTIO_ID_CAIF 12 /* Virtio caif */
-#define VIRTIO_ID_GPU 16 /* virtio GPU */
-#define VIRTIO_ID_INPUT 18 /* virtio input */
+struct virtio_pstore_hdr {
+ __virtio64 id;
+ __virtio32 flags;
+ __virtio16 cmd;
+ __virtio16 type;
+ __virtio64 time_sec;
+ __virtio32 time_nsec;
+ __virtio32 unused;
+};
-#endif /* _LINUX_VIRTIO_IDS_H */
+#endif /* _LINUX_VIRTIO_PSTORE_H */
diff --git a/qdev-monitor.c b/qdev-monitor.c
index e19617f..e1df5a9 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -73,6 +73,7 @@ static const QDevAlias qdev_alias_table[] = {
{ "virtio-serial-pci", "virtio-serial", QEMU_ARCH_ALL & ~QEMU_ARCH_S390X },
{ "virtio-tablet-ccw", "virtio-tablet", QEMU_ARCH_S390X },
{ "virtio-tablet-pci", "virtio-tablet", QEMU_ARCH_ALL & ~QEMU_ARCH_S390X },
+ { "virtio-pstore-pci", "virtio-pstore" },
{ }
};
--
2.8.0
--
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