From aabd6a8fa5a933bdf968cd86e34122745c1960e8 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sjur=20Br=C3=83=C2=A6ndeland?= Date: Mon, 18 Mar 2013 19:19:14 +1030 Subject: Revert "virtio_console: Initialize guest_connected=true for rproc_serial" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit 8078db789a92b10ff6e2d713231b5367e014c53b, and adds a lengthy comment explaining the problem area. The reverted patch caused opening of ports to fail for rproc_serial. In probe guest_connected was set to true, but port_fops_open() fails with -EMFILE if guest_connected already is true. Signed-off-by: Sjur Brændeland Acked-by: Amit Shah Signed-off-by: Rusty Russell --- drivers/char/virtio_console.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index e905d5f5..e6ba6b7 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -1436,7 +1436,7 @@ static int add_port(struct ports_device *portdev, u32 id) * rproc_serial does not want the console port, only * the generic port implementation. */ - port->host_connected = port->guest_connected = true; + port->host_connected = true; else if (!use_multiport(port->portdev)) { /* * If we're not using multiport support, @@ -1752,13 +1752,23 @@ static void in_intr(struct virtqueue *vq) port->inbuf = get_inbuf(port); /* - * Don't queue up data when port is closed. This condition + * Normally the port should not accept data when the port is + * closed. For generic serial ports, the host won't (shouldn't) + * send data till the guest is connected. But this condition * can be reached when a console port is not yet connected (no - * tty is spawned) and the host sends out data to console - * ports. For generic serial ports, the host won't - * (shouldn't) send data till the guest is connected. + * tty is spawned) and the other side sends out data over the + * vring, or when a remote devices start sending data before + * the ports are opened. + * + * A generic serial port will discard data if not connected, + * while console ports and rproc-serial ports accepts data at + * any time. rproc-serial is initiated with guest_connected to + * false because port_fops_open expects this. Console ports are + * hooked up with an HVC console and is initialized with + * guest_connected to true. */ - if (!port->guest_connected) + + if (!port->guest_connected && !is_rproc_serial(port->portdev->vdev)) discard_port_data(port); spin_unlock_irqrestore(&port->inbuf_lock, flags); -- cgit v1.1 From b7d44d9487a11e835de10908f4ab30b4290c0b7f Mon Sep 17 00:00:00 2001 From: Satoru Takeuchi Date: Wed, 20 Mar 2013 11:28:51 +1030 Subject: hw_random: free rng_buffer at module exit rng-core module allocates rng_buffer by kmalloc() since commit f7f154f1246ccc5a0a7e9ce50932627d60a0c878. But this buffer won't be freed and there is a memory leak possibility at module exit. Signed-off-by: Satoru Takeuchi Signed-off-by: Rusty Russell --- drivers/char/hw_random/core.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'drivers/char') diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 69ae597..a0f7724 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -380,6 +380,15 @@ void hwrng_unregister(struct hwrng *rng) } EXPORT_SYMBOL_GPL(hwrng_unregister); +static void __exit hwrng_exit(void) +{ + mutex_lock(&rng_mutex); + BUG_ON(current_rng); + kfree(rng_buffer); + mutex_unlock(&rng_mutex); +} + +module_exit(hwrng_exit); MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver"); MODULE_LICENSE("GPL"); -- cgit v1.1 From 165b1b8bbc17c9469b053bab78b11b7cbce6d161 Mon Sep 17 00:00:00 2001 From: Amit Shah Date: Fri, 29 Mar 2013 16:30:07 +0530 Subject: virtio: console: rename cvq_lock to c_ivq_lock The cvq_lock was taken for the c_ivq. Rename the lock to make that obvious. We'll also add a lock around the c_ovq in the next commit, so there's no ambiguity. Signed-off-by: Amit Shah Reviewed-by: Asias He Reviewed-by: Wanlong Gao Signed-off-by: Rusty Russell Cc: stable@kernel.org --- drivers/char/virtio_console.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index e6ba6b7..2dd9134 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -149,7 +149,7 @@ struct ports_device { spinlock_t ports_lock; /* To protect the vq operations for the control channel */ - spinlock_t cvq_lock; + spinlock_t c_ivq_lock; /* The current config space is stored here */ struct virtio_console_config config; @@ -1709,23 +1709,23 @@ static void control_work_handler(struct work_struct *work) portdev = container_of(work, struct ports_device, control_work); vq = portdev->c_ivq; - spin_lock(&portdev->cvq_lock); + spin_lock(&portdev->c_ivq_lock); while ((buf = virtqueue_get_buf(vq, &len))) { - spin_unlock(&portdev->cvq_lock); + spin_unlock(&portdev->c_ivq_lock); buf->len = len; buf->offset = 0; handle_control_message(portdev, buf); - spin_lock(&portdev->cvq_lock); + spin_lock(&portdev->c_ivq_lock); if (add_inbuf(portdev->c_ivq, buf) < 0) { dev_warn(&portdev->vdev->dev, "Error adding buffer to queue\n"); free_buf(buf, false); } } - spin_unlock(&portdev->cvq_lock); + spin_unlock(&portdev->c_ivq_lock); } static void out_intr(struct virtqueue *vq) @@ -1996,10 +1996,11 @@ static int virtcons_probe(struct virtio_device *vdev) if (multiport) { unsigned int nr_added_bufs; - spin_lock_init(&portdev->cvq_lock); + spin_lock_init(&portdev->c_ivq_lock); INIT_WORK(&portdev->control_work, &control_work_handler); - nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock); + nr_added_bufs = fill_queue(portdev->c_ivq, + &portdev->c_ivq_lock); if (!nr_added_bufs) { dev_err(&vdev->dev, "Error allocating buffers for control queue\n"); @@ -2150,7 +2151,7 @@ static int virtcons_restore(struct virtio_device *vdev) return ret; if (use_multiport(portdev)) - fill_queue(portdev->c_ivq, &portdev->cvq_lock); + fill_queue(portdev->c_ivq, &portdev->c_ivq_lock); list_for_each_entry(port, &portdev->ports, list) { port->in_vq = portdev->in_vqs[port->id]; -- cgit v1.1 From 9ba5c80b1aea8648a3efe5f22dc1f7cacdfbeeb8 Mon Sep 17 00:00:00 2001 From: Amit Shah Date: Fri, 29 Mar 2013 16:30:08 +0530 Subject: virtio: console: add locking around c_ovq operations When multiple ovq operations are being performed (lots of open/close operations on virtio_console fds), the __send_control_msg() function can get confused without locking. A simple recipe to cause badness is: * create a QEMU VM with two virtio-serial ports * in the guest, do while true;do echo abc >/dev/vport0p1;done while true;do echo edf >/dev/vport0p2;done In one run, this caused a panic in __send_control_msg(). In another, I got virtio_console virtio0: control-o:id 0 is not a head! This also results repeated messages similar to these on the host: qemu-kvm: virtio-serial-bus: Unexpected port id 478762112 for device virtio-serial-bus.0 qemu-kvm: virtio-serial-bus: Unexpected port id 478762368 for device virtio-serial-bus.0 Reported-by: FuXiangChun Signed-off-by: Amit Shah Reviewed-by: Wanlong Gao Reviewed-by: Asias He Signed-off-by: Rusty Russell Cc: stable@kernel.org --- drivers/char/virtio_console.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/char') diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 2dd9134..ce5f3fc 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -150,6 +150,7 @@ struct ports_device { /* To protect the vq operations for the control channel */ spinlock_t c_ivq_lock; + spinlock_t c_ovq_lock; /* The current config space is stored here */ struct virtio_console_config config; @@ -569,11 +570,14 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id, vq = portdev->c_ovq; sg_init_one(sg, &cpkt, sizeof(cpkt)); + + spin_lock(&portdev->c_ovq_lock); if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) { virtqueue_kick(vq); while (!virtqueue_get_buf(vq, &len)) cpu_relax(); } + spin_unlock(&portdev->c_ovq_lock); return 0; } @@ -1997,6 +2001,7 @@ static int virtcons_probe(struct virtio_device *vdev) unsigned int nr_added_bufs; spin_lock_init(&portdev->c_ivq_lock); + spin_lock_init(&portdev->c_ovq_lock); INIT_WORK(&portdev->control_work, &control_work_handler); nr_added_bufs = fill_queue(portdev->c_ivq, -- cgit v1.1