7 files changed, 48 insertions, 16 deletions

diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 6a22c19da663..bdf8532494fe 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -7,8 +7,7 @@
  * kernel and insert a module (lg.ko) which allows us to run other Linux
  * kernels the same way we'd run processes.  We call the first kernel the Host,
  * and the others the Guests.  The program which sets up and configures Guests
- * (such as the example in Documentation/virtual/lguest/lguest.c) is called the
- * Launcher.
+ * (such as the example in tools/lguest/lguest.c) is called the Launcher.
  *
  * Secondly, we only run specially modified Guests, not normal kernels: setting
  * CONFIG_LGUEST_GUEST to "y" compiles this file into the kernel so it knows
@@ -1057,6 +1056,12 @@ static void lguest_load_sp0(struct tss_struct *tss,
 }
 
 /* Let's just say, I wouldn't do debugging under a Guest. */
+static unsigned long lguest_get_debugreg(int regno)
+{
+        /* FIXME: Implement */
+        return 0;
+}
+
 static void lguest_set_debugreg(int regno, unsigned long value)
 {
         /* FIXME: Implement */
@@ -1304,6 +1309,7 @@ __init void lguest_init(void)
         pv_cpu_ops.load_tr_desc = lguest_load_tr_desc;
         pv_cpu_ops.set_ldt = lguest_set_ldt;
         pv_cpu_ops.load_tls = lguest_load_tls;
+        pv_cpu_ops.get_debugreg = lguest_get_debugreg;
         pv_cpu_ops.set_debugreg = lguest_set_debugreg;
         pv_cpu_ops.clts = lguest_clts;
         pv_cpu_ops.read_cr0 = lguest_read_cr0;
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index fc45567ad3ac..b79cf3e1b793 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1529,18 +1529,22 @@ static void remove_port_data(struct port *port)
 {
         struct port_buffer *buf;
 
+        spin_lock_irq(&port->inbuf_lock);
         /* Remove unused data this port might have received. */
         discard_port_data(port);
 
-        reclaim_consumed_buffers(port);
-
         /* Remove buffers we queued up for the Host to send us data in. */
         while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
                 free_buf(buf, true);
+        spin_unlock_irq(&port->inbuf_lock);
+
+        spin_lock_irq(&port->outvq_lock);
+        reclaim_consumed_buffers(port);
 
         /* Free pending buffers from the out-queue. */
         while ((buf = virtqueue_detach_unused_buf(port->out_vq)))
                 free_buf(buf, true);
+        spin_unlock_irq(&port->outvq_lock);
 }
 
 /*
@@ -1554,6 +1558,7 @@ static void unplug_port(struct port *port)
         list_del(&port->list);
         spin_unlock_irq(&port->portdev->ports_lock);
 
+        spin_lock_irq(&port->inbuf_lock);
         if (port->guest_connected) {
                 /* Let the app know the port is going down. */
                 send_sigio_to_port(port);
@@ -1564,6 +1569,7 @@ static void unplug_port(struct port *port)
 
                 wake_up_interruptible(&port->waitqueue);
         }
+        spin_unlock_irq(&port->inbuf_lock);
 
         if (is_console_port(port)) {
                 spin_lock_irq(&pdrvdata_lock);
@@ -1585,9 +1591,8 @@ static void unplug_port(struct port *port)
         device_destroy(pdrvdata.class, port->dev->devt);
         cdev_del(port->cdev);
 
-        kfree(port->name);
-
         debugfs_remove(port->debugfs_file);
+        kfree(port->name);
 
         /*
          * Locks around here are not necessary - a port can't be
@@ -1681,7 +1686,9 @@ static void handle_control_message(struct ports_device *portdev,
                  * If the guest is connected, it'll be interested in
                  * knowing the host connection state changed.
                  */
+                spin_lock_irq(&port->inbuf_lock);
                 send_sigio_to_port(port);
+                spin_unlock_irq(&port->inbuf_lock);
                 break;
         case VIRTIO_CONSOLE_PORT_NAME:
                 /*
@@ -1801,13 +1808,13 @@ static void in_intr(struct virtqueue *vq)
         if (!port->guest_connected && !is_rproc_serial(port->portdev->vdev))
                 discard_port_data(port);
 
+        /* Send a SIGIO indicating new data in case the process asked for it */
+        send_sigio_to_port(port);
+
         spin_unlock_irqrestore(&port->inbuf_lock, flags);
 
         wake_up_interruptible(&port->waitqueue);
 
-        /* Send a SIGIO indicating new data in case the process asked for it */
-        send_sigio_to_port(port);
-
         if (is_console_port(port) && hvc_poll(port->cons.hvc))
                 hvc_kick();
 }
@@ -2241,10 +2248,8 @@ static int __init init(void)
         }
 
         pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
-        if (!pdrvdata.debugfs_dir) {
-                pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
-                           PTR_ERR(pdrvdata.debugfs_dir));
-        }
+        if (!pdrvdata.debugfs_dir)
+                pr_warning("Error creating debugfs dir for virtio-ports\n");
         INIT_LIST_HEAD(&pdrvdata.consoles);
         INIT_LIST_HEAD(&pdrvdata.portdevs);
 
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index 28433a155d67..70dfcdc29f1f 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -140,6 +140,16 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi,
         cpu->regs->eip = idt_address(lo, hi);
 
         /*
+         * Trapping always clears these flags:
+         * TF: Trap flag
+         * VM: Virtual 8086 mode
+         * RF: Resume
+         * NT: Nested task.
+         */
+        cpu->regs->eflags &=
+                ~(X86_EFLAGS_TF|X86_EFLAGS_VM|X86_EFLAGS_RF|X86_EFLAGS_NT);
+
+        /*
          * There are two kinds of interrupt handlers: 0xE is an "interrupt
          * gate" which expects interrupts to be disabled on entry.
          */
diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c
index a35d8d100165..bfb39bb56ef1 100644
--- a/drivers/lguest/page_tables.c
+++ b/drivers/lguest/page_tables.c
@@ -669,8 +669,10 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr)