Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/xen/xenbus/xenbus.h b/drivers/xen/xenbus/xenbus.h
index 0929811..d75a238 100644
--- a/drivers/xen/xenbus/xenbus.h
+++ b/drivers/xen/xenbus/xenbus.h
@@ -83,6 +83,7 @@
int num_vecs;
int err;
enum xb_req_state state;
+ bool user_req;
void (*cb)(struct xb_req_data *);
void *par;
};
@@ -133,4 +134,6 @@
int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void *par);
void xenbus_dev_queue_reply(struct xb_req_data *req);
+extern unsigned int xb_dev_generation_id;
+
#endif
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index a1c1700..e17ca81 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -278,10 +278,8 @@
dev_err(&dev->dev, "%s\n", printf_buffer);
path_buffer = kasprintf(GFP_KERNEL, "error/%s", dev->nodename);
- if (!path_buffer ||
- xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer))
- dev_err(&dev->dev, "failed to write error node for %s (%s)\n",
- dev->nodename, printf_buffer);
+ if (path_buffer)
+ xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer);
kfree(printf_buffer);
kfree(path_buffer);
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index c3e2010..597af45 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -55,6 +55,7 @@
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/miscdevice.h>
+#include <linux/workqueue.h>
#include <xen/xenbus.h>
#include <xen/xen.h>
@@ -62,6 +63,8 @@
#include "xenbus.h"
+unsigned int xb_dev_generation_id;
+
/*
* An element of a list of outstanding transactions, for which we're
* still waiting a reply.
@@ -69,6 +72,7 @@
struct xenbus_transaction_holder {
struct list_head list;
struct xenbus_transaction handle;
+ unsigned int generation_id;
};
/*
@@ -113,6 +117,8 @@
wait_queue_head_t read_waitq;
struct kref kref;
+
+ struct work_struct wq;
};
/* Read out any raw xenbus messages queued up. */
@@ -297,14 +303,14 @@
mutex_unlock(&adap->dev_data->reply_mutex);
}
-static void xenbus_file_free(struct kref *kref)
+static void xenbus_worker(struct work_struct *wq)
{
struct xenbus_file_priv *u;
struct xenbus_transaction_holder *trans, *tmp;
struct watch_adapter *watch, *tmp_watch;
struct read_buffer *rb, *tmp_rb;
- u = container_of(kref, struct xenbus_file_priv, kref);
+ u = container_of(wq, struct xenbus_file_priv, wq);
/*
* No need for locking here because there are no other users,
@@ -330,6 +336,18 @@
kfree(u);
}
+static void xenbus_file_free(struct kref *kref)
+{
+ struct xenbus_file_priv *u;
+
+ /*
+ * We might be called in xenbus_thread().
+ * Use workqueue to avoid deadlock.
+ */
+ u = container_of(kref, struct xenbus_file_priv, kref);
+ schedule_work(&u->wq);
+}
+
static struct xenbus_transaction_holder *xenbus_get_transaction(
struct xenbus_file_priv *u, uint32_t tx_id)
{
@@ -441,6 +459,7 @@
rc = -ENOMEM;
goto out;
}
+ trans->generation_id = xb_dev_generation_id;
list_add(&trans->list, &u->transactions);
} else if (msg->hdr.tx_id != 0 &&
!xenbus_get_transaction(u, msg->hdr.tx_id))
@@ -449,6 +468,20 @@
!(msg->hdr.len == 2 &&
(!strcmp(msg->body, "T") || !strcmp(msg->body, "F"))))
return xenbus_command_reply(u, XS_ERROR, "EINVAL");
+ else if (msg_type == XS_TRANSACTION_END) {
+ trans = xenbus_get_transaction(u, msg->hdr.tx_id);
+ if (trans && trans->generation_id != xb_dev_generation_id) {
+ list_del(&trans->list);
+ kfree(trans);
+ if (!strcmp(msg->body, "T"))
+ return xenbus_command_reply(u, XS_ERROR,
+ "EAGAIN");
+ else
+ return xenbus_command_reply(u,
+ XS_TRANSACTION_END,
+ "OK");
+ }
+ }
rc = xenbus_dev_request_and_reply(&msg->hdr, u);
if (rc && trans) {
@@ -465,7 +498,6 @@
struct watch_adapter *watch;
char *path, *token;
int err, rc;
- LIST_HEAD(staging_q);
path = u->u.buffer + sizeof(u->u.msg);
token = memchr(path, 0, u->u.msg.len);
@@ -523,7 +555,6 @@
uint32_t msg_type;
int rc = len;
int ret;
- LIST_HEAD(staging_q);
/*
* We're expecting usermode to be writing properly formed
@@ -622,9 +653,7 @@
if (xen_store_evtchn == 0)
return -ENOENT;
- nonseekable_open(inode, filp);
-
- filp->f_mode &= ~FMODE_ATOMIC_POS; /* cdev-style semantics */
+ stream_open(inode, filp);
u = kzalloc(sizeof(*u), GFP_KERNEL);
if (u == NULL)
@@ -636,6 +665,7 @@
INIT_LIST_HEAD(&u->watches);
INIT_LIST_HEAD(&u->read_buffers);
init_waitqueue_head(&u->read_waitq);
+ INIT_WORK(&u->wq, xenbus_worker);
mutex_init(&u->reply_mutex);
mutex_init(&u->msgbuffer_mutex);
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 07896f4..a7d90a7 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#define DPRINTK(fmt, ...) \
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index 49a3874..ddc18da 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -105,6 +105,7 @@
static void xs_suspend_exit(void)
{
+ xb_dev_generation_id++;
spin_lock(&xs_state_lock);
xs_suspend_active--;
spin_unlock(&xs_state_lock);
@@ -125,7 +126,7 @@
spin_lock(&xs_state_lock);
}
- if (req->type == XS_TRANSACTION_START)
+ if (req->type == XS_TRANSACTION_START && !req->user_req)
xs_state_users++;
xs_state_users++;
rq_id = xs_request_id++;
@@ -140,7 +141,7 @@
spin_lock(&xs_state_lock);
xs_state_users--;
if ((req->type == XS_TRANSACTION_START && req->msg.type == XS_ERROR) ||
- (req->type == XS_TRANSACTION_END &&
+ (req->type == XS_TRANSACTION_END && !req->user_req &&
!WARN_ON_ONCE(req->msg.type == XS_ERROR &&
!strcmp(req->body, "ENOENT"))))
xs_state_users--;
@@ -286,6 +287,7 @@
req->num_vecs = 1;
req->cb = xenbus_dev_queue_reply;
req->par = par;
+ req->user_req = true;
xs_send(req, msg);
@@ -313,6 +315,7 @@
req->vec = iovec;
req->num_vecs = num_vecs;
req->cb = xs_wake_up;
+ req->user_req = false;
msg.req_id = 0;
msg.tx_id = t.id;