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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/bluetooth/virtio_bt.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/bluetooth/virtio_bt.c')
-rw-r--r--drivers/bluetooth/virtio_bt.c454
1 files changed, 454 insertions, 0 deletions
diff --git a/drivers/bluetooth/virtio_bt.c b/drivers/bluetooth/virtio_bt.c
new file mode 100644
index 000000000..c20d54088
--- /dev/null
+++ b/drivers/bluetooth/virtio_bt.c
@@ -0,0 +1,454 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/skbuff.h>
+
+#include <uapi/linux/virtio_ids.h>
+#include <uapi/linux/virtio_bt.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#define VERSION "0.1"
+#define VIRTBT_RX_BUF_SIZE 1000
+
+enum {
+ VIRTBT_VQ_TX,
+ VIRTBT_VQ_RX,
+ VIRTBT_NUM_VQS,
+};
+
+struct virtio_bluetooth {
+ struct virtio_device *vdev;
+ struct virtqueue *vqs[VIRTBT_NUM_VQS];
+ struct work_struct rx;
+ struct hci_dev *hdev;
+};
+
+static int virtbt_add_inbuf(struct virtio_bluetooth *vbt)
+{
+ struct virtqueue *vq = vbt->vqs[VIRTBT_VQ_RX];
+ struct scatterlist sg[1];
+ struct sk_buff *skb;
+ int err;
+
+ skb = alloc_skb(VIRTBT_RX_BUF_SIZE, GFP_KERNEL);
+ if (!skb)
+ return -ENOMEM;
+
+ sg_init_one(sg, skb->data, VIRTBT_RX_BUF_SIZE);
+
+ err = virtqueue_add_inbuf(vq, sg, 1, skb, GFP_KERNEL);
+ if (err < 0) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ return 0;
+}
+
+static int virtbt_open(struct hci_dev *hdev)
+{
+ return 0;
+}
+
+static int virtbt_open_vdev(struct virtio_bluetooth *vbt)
+{
+ if (virtbt_add_inbuf(vbt) < 0)
+ return -EIO;
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_RX]);
+ return 0;
+}
+
+static int virtbt_close(struct hci_dev *hdev)
+{
+ return 0;
+}
+
+static int virtbt_close_vdev(struct virtio_bluetooth *vbt)
+{
+ int i;
+
+ cancel_work_sync(&vbt->rx);
+
+ for (i = 0; i < ARRAY_SIZE(vbt->vqs); i++) {
+ struct virtqueue *vq = vbt->vqs[i];
+ struct sk_buff *skb;
+
+ while ((skb = virtqueue_detach_unused_buf(vq)))
+ kfree_skb(skb);
+ cond_resched();
+ }
+
+ return 0;
+}
+
+static int virtbt_flush(struct hci_dev *hdev)
+{
+ return 0;
+}
+
+static int virtbt_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct virtio_bluetooth *vbt = hci_get_drvdata(hdev);
+ struct scatterlist sg[1];
+ int err;
+
+ memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+
+ sg_init_one(sg, skb->data, skb->len);
+ err = virtqueue_add_outbuf(vbt->vqs[VIRTBT_VQ_TX], sg, 1, skb,
+ GFP_KERNEL);
+ if (err) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_TX]);
+ return 0;
+}
+
+static int virtbt_setup_zephyr(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Read Build Information */
+ skb = __hci_cmd_sync(hdev, 0xfc08, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ /* Bounded print: the backend controls skb->len. */
+ if (skb->len > 1) {
+ int len = skb->len - 1;
+
+ bt_dev_info(hdev, "%.*s", len, (char *)(skb->data + 1));
+ hci_set_fw_info(hdev, "%.*s", len, skb->data + 1);
+ }
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_set_bdaddr_zephyr(struct hci_dev *hdev,
+ const bdaddr_t *bdaddr)
+{
+ struct sk_buff *skb;
+
+ /* Write BD_ADDR */
+ skb = __hci_cmd_sync(hdev, 0xfc06, 6, bdaddr, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_setup_intel(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Intel Read Version */
+ skb = __hci_cmd_sync(hdev, 0xfc05, 0, NULL, HCI_CMD_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_set_bdaddr_intel(struct hci_dev *hdev, const bdaddr_t *bdaddr)
+{
+ struct sk_buff *skb;
+
+ /* Intel Write BD Address */
+ skb = __hci_cmd_sync(hdev, 0xfc31, 6, bdaddr, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_setup_realtek(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Read ROM Version */
+ skb = __hci_cmd_sync(hdev, 0xfc6d, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ bt_dev_info(hdev, "ROM version %u", *((__u8 *) (skb->data + 1)));
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_shutdown_generic(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Reset */
+ skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static void virtbt_rx_handle(struct virtio_bluetooth *vbt, struct sk_buff *skb)
+{
+ size_t min_hdr;
+ __u8 pkt_type;
+
+ pkt_type = *((__u8 *) skb->data);
+ skb_pull(skb, 1);
+
+ switch (pkt_type) {
+ case HCI_EVENT_PKT:
+ min_hdr = sizeof(struct hci_event_hdr);
+ break;
+ case HCI_ACLDATA_PKT:
+ min_hdr = sizeof(struct hci_acl_hdr);
+ break;
+ case HCI_SCODATA_PKT:
+ min_hdr = sizeof(struct hci_sco_hdr);
+ break;
+ case HCI_ISODATA_PKT:
+ min_hdr = sizeof(struct hci_iso_hdr);
+ break;
+ default:
+ kfree_skb(skb);
+ return;
+ }
+
+ if (skb->len < min_hdr) {
+ bt_dev_err_ratelimited(vbt->hdev,
+ "rx pkt_type 0x%02x payload %u < hdr %zu\n",
+ pkt_type, skb->len, min_hdr);
+ kfree_skb(skb);
+ return;
+ }
+
+ hci_skb_pkt_type(skb) = pkt_type;
+ hci_recv_frame(vbt->hdev, skb);
+}
+
+static void virtbt_rx_work(struct work_struct *work)
+{
+ struct virtio_bluetooth *vbt = container_of(work,
+ struct virtio_bluetooth, rx);
+ struct sk_buff *skb;
+ unsigned int len;
+
+ skb = virtqueue_get_buf(vbt->vqs[VIRTBT_VQ_RX], &len);
+ if (!skb)
+ return;
+
+ if (!len || len > VIRTBT_RX_BUF_SIZE) {
+ bt_dev_err_ratelimited(vbt->hdev,
+ "rx reply len %u outside [1, %u]\n",
+ len, VIRTBT_RX_BUF_SIZE);
+ kfree_skb(skb);
+ } else {
+ skb_put(skb, len);
+ virtbt_rx_handle(vbt, skb);
+ }
+
+ if (virtbt_add_inbuf(vbt) < 0)
+ return;
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_RX]);
+}
+
+static void virtbt_tx_done(struct virtqueue *vq)
+{
+ struct sk_buff *skb;
+ unsigned int len;
+
+ while ((skb = virtqueue_get_buf(vq, &len)))
+ kfree_skb(skb);
+}
+
+static void virtbt_rx_done(struct virtqueue *vq)
+{
+ struct virtio_bluetooth *vbt = vq->vdev->priv;
+
+ schedule_work(&vbt->rx);
+}
+
+static int virtbt_probe(struct virtio_device *vdev)
+{
+ struct virtqueue_info vqs_info[VIRTBT_NUM_VQS] = {
+ [VIRTBT_VQ_TX] = { "tx", virtbt_tx_done },
+ [VIRTBT_VQ_RX] = { "rx", virtbt_rx_done },
+ };
+ struct virtio_bluetooth *vbt;
+ struct hci_dev *hdev;
+ int err;
+ __u8 type;
+
+ if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+ return -ENODEV;
+
+ type = virtio_cread8(vdev, offsetof(struct virtio_bt_config, type));
+
+ switch (type) {
+ case VIRTIO_BT_CONFIG_TYPE_PRIMARY:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ vbt = kzalloc_obj(*vbt);
+ if (!vbt)
+ return -ENOMEM;
+
+ vdev->priv = vbt;
+ vbt->vdev = vdev;
+
+ INIT_WORK(&vbt->rx, virtbt_rx_work);
+
+ err = virtio_find_vqs(vdev, VIRTBT_NUM_VQS, vbt->vqs, vqs_info, NULL);
+ if (err)
+ return err;
+
+ hdev = hci_alloc_dev();
+ if (!hdev) {
+ err = -ENOMEM;
+ goto failed;
+ }
+
+ vbt->hdev = hdev;
+
+ hdev->bus = HCI_VIRTIO;
+ hci_set_drvdata(hdev, vbt);
+
+ hdev->open = virtbt_open;
+ hdev->close = virtbt_close;
+ hdev->flush = virtbt_flush;
+ hdev->send = virtbt_send_frame;
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_VND_HCI)) {
+ __u16 vendor;
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_CONFIG_V2))
+ virtio_cread(vdev, struct virtio_bt_config_v2,
+ vendor, &vendor);
+ else
+ virtio_cread(vdev, struct virtio_bt_config,
+ vendor, &vendor);
+
+ switch (vendor) {
+ case VIRTIO_BT_CONFIG_VENDOR_ZEPHYR:
+ hdev->manufacturer = 1521;
+ hdev->setup = virtbt_setup_zephyr;
+ hdev->shutdown = virtbt_shutdown_generic;
+ hdev->set_bdaddr = virtbt_set_bdaddr_zephyr;
+ break;
+
+ case VIRTIO_BT_CONFIG_VENDOR_INTEL:
+ hdev->manufacturer = 2;
+ hdev->setup = virtbt_setup_intel;
+ hdev->shutdown = virtbt_shutdown_generic;
+ hdev->set_bdaddr = virtbt_set_bdaddr_intel;
+ hci_set_quirk(hdev, HCI_QUIRK_STRICT_DUPLICATE_FILTER);
+ hci_set_quirk(hdev, HCI_QUIRK_SIMULTANEOUS_DISCOVERY);
+ hci_set_quirk(hdev, HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED);
+ break;
+
+ case VIRTIO_BT_CONFIG_VENDOR_REALTEK:
+ hdev->manufacturer = 93;
+ hdev->setup = virtbt_setup_realtek;
+ hdev->shutdown = virtbt_shutdown_generic;
+ hci_set_quirk(hdev, HCI_QUIRK_SIMULTANEOUS_DISCOVERY);
+ hci_set_quirk(hdev, HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED);
+ break;
+ }
+ }
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_MSFT_EXT)) {
+ __u16 msft_opcode;
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_CONFIG_V2))
+ virtio_cread(vdev, struct virtio_bt_config_v2,
+ msft_opcode, &msft_opcode);
+ else
+ virtio_cread(vdev, struct virtio_bt_config,
+ msft_opcode, &msft_opcode);
+
+ hci_set_msft_opcode(hdev, msft_opcode);
+ }
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_AOSP_EXT))
+ hci_set_aosp_capable(hdev);
+
+ if (hci_register_dev(hdev) < 0) {
+ hci_free_dev(hdev);
+ err = -EBUSY;
+ goto failed;
+ }
+
+ virtio_device_ready(vdev);
+ err = virtbt_open_vdev(vbt);
+ if (err)
+ goto open_failed;
+
+ return 0;
+
+open_failed:
+ hci_free_dev(hdev);
+failed:
+ vdev->config->del_vqs(vdev);
+ return err;
+}
+
+static void virtbt_remove(struct virtio_device *vdev)
+{
+ struct virtio_bluetooth *vbt = vdev->priv;
+ struct hci_dev *hdev = vbt->hdev;
+
+ hci_unregister_dev(hdev);
+ virtio_reset_device(vdev);
+ virtbt_close_vdev(vbt);
+
+ hci_free_dev(hdev);
+ vbt->hdev = NULL;
+
+ vdev->config->del_vqs(vdev);
+ kfree(vbt);
+}
+
+static struct virtio_device_id virtbt_table[] = {
+ { VIRTIO_ID_BT, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+MODULE_DEVICE_TABLE(virtio, virtbt_table);
+
+static const unsigned int virtbt_features[] = {
+ VIRTIO_BT_F_VND_HCI,
+ VIRTIO_BT_F_MSFT_EXT,
+ VIRTIO_BT_F_AOSP_EXT,
+ VIRTIO_BT_F_CONFIG_V2,
+};
+
+static struct virtio_driver virtbt_driver = {
+ .driver.name = KBUILD_MODNAME,
+ .feature_table = virtbt_features,
+ .feature_table_size = ARRAY_SIZE(virtbt_features),
+ .id_table = virtbt_table,
+ .probe = virtbt_probe,
+ .remove = virtbt_remove,
+};
+
+module_virtio_driver(virtbt_driver);
+
+MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
+MODULE_DESCRIPTION("Generic Bluetooth VIRTIO driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");