kernel.git/drivers/char/virtio_console.c, branch linux-3.8.y

virtio: console: add locking around c_ovq operations

2013-04-05T16:26:15Z

commit 9ba5c80b1aea8648a3efe5f22dc1f7cacdfbeeb8 upstream. 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 Signed-off-by: Greg Kroah-Hartman

virtio: console: rename cvq_lock to c_ivq_lock

2013-04-05T16:26:15Z

commit 165b1b8bbc17c9469b053bab78b11b7cbce6d161 upstream. 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 Signed-off-by: Greg Kroah-Hartman

virtio_console: Don't access uninitialized data.

2013-02-07T01:07:37Z

Don't access uninitialized work-queue when removing device. The work queue is initialized only if the device multi-queue. So don't call cancel_work unless this is a multi-queue device. This fixes the following panic: Kernel panic - not syncing: BUG! Call Trace: 62031b28: [<6026085d>] panic+0x16b/0x2d3 62031b30: [<6004ef5e>] flush_work+0x0/0x1d7 62031b60: [<602606f2>] panic+0x0/0x2d3 62031b68: [<600333b0>] memcpy+0x0/0x140 62031b80: [<6002d58a>] unblock_signals+0x0/0x84 62031ba0: [<602609c5>] printk+0x0/0xa0 62031bd8: [<60264e51>] __mutex_unlock_slowpath+0x13d/0x148 62031c10: [<6004ef5e>] flush_work+0x0/0x1d7 62031c18: [<60050234>] try_to_grab_pending+0x0/0x17e 62031c38: [<6004e984>] get_work_gcwq+0x71/0x8f 62031c48: [<60050539>] __cancel_work_timer+0x5b/0x115 62031c78: [<628acc85>] unplug_port+0x0/0x191 [virtio_console] 62031c98: [<6005061c>] cancel_work_sync+0x12/0x14 62031ca8: [<628ace96>] virtcons_remove+0x80/0x15c [virtio_console] 62031ce8: [<628191de>] virtio_dev_remove+0x1e/0x7e [virtio] 62031d08: [<601cf242>] __device_release_driver+0x75/0xe4 62031d28: [<601cf2dd>] device_release_driver+0x2c/0x40 62031d48: [<601ce0dd>] driver_unbind+0x7d/0xc6 62031d88: [<601cd5d9>] drv_attr_store+0x27/0x29 62031d98: [<60115f61>] sysfs_write_file+0x100/0x14d 62031df8: [<600b737d>] vfs_write+0xcb/0x184 62031e08: [<600b58b8>] filp_close+0x88/0x94 62031e38: [<600b7686>] sys_write+0x59/0x88 62031e88: [<6001ced1>] handle_syscall+0x5d/0x80 62031ea8: [<60030a74>] userspace+0x405/0x531 62031f08: [<600d32cc>] sys_dup+0x0/0x5e 62031f28: [<601b11d6>] strcpy+0x0/0x18 62031f38: [<600be46c>] do_execve+0x10/0x12 62031f48: [<600184c7>] run_init_process+0x43/0x45 62031fd8: [<60019a91>] new_thread_handler+0xba/0xbc Signed-off-by: Sjur Brændeland Cc: stable@kernel.org Signed-off-by: Rusty Russell

Drivers: char: remove __dev* attributes.

2013-01-03T23:57:15Z

CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton Cc: David Airlie Cc: Matt Mackall Cc: Herbert Xu Signed-off-by: Greg Kroah-Hartman

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2012-12-20T16:37:05Z

Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_ to dev_( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...

virtio_console: Add support for remoteproc serial

2012-12-18T04:50:44Z

Add a simple serial connection driver called VIRTIO_ID_RPROC_SERIAL (11) for communicating with a remote processor in an asymmetric multi-processing configuration. This implementation reuses the existing virtio_console implementation, and adds support for DMA allocation of data buffers and disables use of tty console and the virtio control queue. Signed-off-by: Sjur Brændeland Acked-by: Amit Shah Signed-off-by: Rusty Russell

virtio_console: Merge struct buffer_token into struct port_buffer

2012-12-18T04:50:44Z

Refactoring the splice functionality by unifying the approach for sending scatter-lists and regular buffers. This simplifies buffer handling and reduces code size. Splice will now allocate a port_buffer and send_buf() and free_buf() can always be used for any buffer. Signed-off-by: Sjur Brændeland Acked-by: Amit Shah Signed-off-by: Rusty Russell

virtio_console: Free buffers from out-queue upon close

2012-12-18T04:50:41Z

Free pending output buffers from the virtio out-queue when host has acknowledged port_close. Signed-off-by: Sjur Brændeland Signed-off-by: Rusty Russell (rebased & cut down)

virtio_console: Use kmalloc instead of kzalloc

2012-12-18T04:50:39Z

Avoid the more cpu expensive kzalloc when allocating buffers. Originally kzalloc was intended for isolating the guest from the host by not sending random guest data to the host. But device isolation is not yet in place so kzalloc is not really needed. Signed-off-by: Sjur Brændeland Signed-off-by: Rusty Russell

virtio_console: Free buffer if splice fails

2012-12-18T04:50:39Z

Free the allocated scatter list if send_pages fails in function port_splice_write. Signed-off-by: Sjur Brændeland Signed-off-by: Rusty Russell