similar to: PATCH: virtio_console: Fix poll blocking even though there is data to read (version 2)

Hi All, I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there. I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there.

Hi All, I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there. I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there.

From: Hans de Goede <hdegoede at redhat.com> I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there. virtio_console's port_fops_poll checks port->inbuf != NULL to determine if read won't block. However if an application reads enough bytes from

From: Hans de Goede <hdegoede at redhat.com> I found this while working on a Linux agent for spice, the symptom I was seeing was select blocking on the spice vdagent virtio serial port even though there were messages queued up there. virtio_console's port_fops_poll checks port->inbuf != NULL to determine if read won't block. However if an application reads enough bytes from

On 07/19/2013 04:16 AM, Amit Shah wrote: > If a port gets unplugged while a user is blocked on read(), -ENODEV is > returned. However, subsequent read()s returned 0, indicating there's no > host-side connection (but not indicating the device went away). > > This also happened when a port was unplugged and the user didn't have > any blocking operation pending. If the

On 07/19/2013 04:16 AM, Amit Shah wrote: > If a port gets unplugged while a user is blocked on read(), -ENODEV is > returned. However, subsequent read()s returned 0, indicating there's no > host-side connection (but not indicating the device went away). > > This also happened when a port was unplugged and the user didn't have > any blocking operation pending. If the

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

Jason Wang <jasowang at redhat.com> writes: > On 07/22/2013 01:45 PM, Rusty Russell wrote: >> Amit Shah <amit.shah at redhat.com> writes: >>> On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >>>> On 07/19/2013 03:48 PM, Amit Shah wrote: >>>>> On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >>>>>> On 07/19/2013 04:16

Jason Wang <jasowang at redhat.com> writes: > On 07/22/2013 01:45 PM, Rusty Russell wrote: >> Amit Shah <amit.shah at redhat.com> writes: >>> On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >>>> On 07/19/2013 03:48 PM, Amit Shah wrote: >>>>> On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >>>>>> On 07/19/2013 04:16

On (Fri) 19 Jul 2013 [13:07:49], Jason Wang wrote: > On 07/19/2013 04:16 AM, Amit Shah wrote: > > If a port gets unplugged while a user is blocked on read(), -ENODEV is > > returned. However, subsequent read()s returned 0, indicating there's no > > host-side connection (but not indicating the device went away). > > > > This also happened when a port was

Amit Shah <amit.shah at redhat.com> writes: > On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >> On 07/19/2013 03:48 PM, Amit Shah wrote: >> > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> >> On 07/19/2013 04:16 AM, Amit Shah wrote: >> >>> Between poll() being called and processed, the port can be unplugged. >> >>> Check

Amit Shah <amit.shah at redhat.com> writes: > On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >> On 07/19/2013 03:48 PM, Amit Shah wrote: >> > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> >> On 07/19/2013 04:16 AM, Amit Shah wrote: >> >>> Between poll() being called and processed, the port can be unplugged. >> >>> Check

If a port gets unplugged while a user is blocked on read(), -ENODEV is returned. However, subsequent read()s returned 0, indicating there's no host-side connection (but not indicating the device went away). This also happened when a port was unplugged and the user didn't have any blocking operation pending. If the user didn't monitor the SIGIO signal, they won't have a chance to

If a port gets unplugged while a user is blocked on read(), -ENODEV is returned. However, subsequent read()s returned 0, indicating there's no host-side connection (but not indicating the device went away). This also happened when a port was unplugged and the user didn't have any blocking operation pending. If the user didn't monitor the SIGIO signal, they won't have a chance to

Hi Rusty, The main thing in these patches is the introduction of injecting SIGIO on host-side connect/disconnect events and when new data is available for ports. The first two patches fix bugs that I haven't seen, but look like the right thing to do. These have been tested extensively using the test-virtserial test suite. Please apply, Amit. Amit Shah (4): virtio: console: Un-block

Hi Rusty, The main thing in these patches is the introduction of injecting SIGIO on host-side connect/disconnect events and when new data is available for ports. The first two patches fix bugs that I haven't seen, but look like the right thing to do. These have been tested extensively using the test-virtserial test suite. Please apply, Amit. Amit Shah (4): virtio: console: Un-block

Usage: spicevdagent=1|0 (default=0) Enables spice vdagent. The Spice vdagent is an optional component for enhancing user experience and performing guest-oriented management tasks. Its features includes: client mouse mode (no need to grab mouse by client, no mouse lag), automatic adjustment of screen resolution, copy and paste (text and image) between client and domU. It also requires vdagent

When removing a port we don't check if a program was blocked for read. This leads to a crash when SIGTERM is sent to the program after hot-unplugging the port. Signed-off-by: Amit Shah <amit.shah at redhat.com> --- drivers/char/virtio_console.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c

When removing a port we don't check if a program was blocked for read. This leads to a crash when SIGTERM is sent to the program after hot-unplugging the port. Signed-off-by: Amit Shah <amit.shah at redhat.com> --- drivers/char/virtio_console.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c