search for: virtio_console_device_readi

Hello, This patchset is still based on Linus' tree but I'll rebase when Rusty sends out the disable multiport patches. This series reworks the ABI to allow port discovery (only) via the control queue. In addition, it adds support for non-blocking write() support, which means no spinning. This works fine with the recent patches that are on qemu-devel. Also included is removal of

Hello, This patchset is still based on Linus' tree but I'll rebase when Rusty sends out the disable multiport patches. This series reworks the ABI to allow port discovery (only) via the control queue. In addition, it adds support for non-blocking write() support, which means no spinning. This works fine with the recent patches that are on qemu-devel. Also included is removal of

When we hot unplug a virtserialport and then try to hot plug again, it fails: (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 (qemu) device_del serial0 (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\

When we hot unplug a virtserialport and then try to hot plug again, it fails: (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 (qemu) device_del serial0 (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\

When we hot unplug a virtserialport and then try to hot plug again, it fails: (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 (qemu) device_del serial0 (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\

When we hot unplug a virtserialport and then try to hot plug again, it fails: (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 (qemu) device_del serial0 (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\

Hello, This series reworks the ABI to allow port discovery (only) via the control queue and enable multiport again. In addition, it adds support for non-blocking write() support, which means no spinning. This works fine with the recent patches that are on qemu-devel. Also included is removal of hvc_remove() as removing one such console port causes other console ports (registered with hvc) to

Hello, This series reworks the ABI to allow port discovery (only) via the control queue and enable multiport again. In addition, it adds support for non-blocking write() support, which means no spinning. This works fine with the recent patches that are on qemu-devel. Also included is removal of hvc_remove() as removing one such console port causes other console ports (registered with hvc) to

If we're using multiport, there's no point in always creating a console port. Create the console port only if the host doesn't support multiport. Signed-off-by: Amit Shah <amit.shah at redhat.com> --- drivers/char/virtio_console.c | 32 +++++++++++++++----------------- 1 files changed, 15 insertions(+), 17 deletions(-) diff --git a/drivers/char/virtio_console.c

If we're using multiport, there's no point in always creating a console port. Create the console port only if the host doesn't support multiport. Signed-off-by: Amit Shah <amit.shah at redhat.com> --- drivers/char/virtio_console.c | 32 +++++++++++++++----------------- 1 files changed, 15 insertions(+), 17 deletions(-) diff --git a/drivers/char/virtio_console.c

On Wed, Nov 13, 2019 at 04:00:56PM +0100, Laurent Vivier wrote: > When we hot unplug a virtserialport and then try to hot plug again, > it fails: > > (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait > (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ > chardev=serial0,id=serial0,name=serial0 > (qemu) device_del serial0 >

On Thu, 2019-11-14 at 13:25 +0100, Laurent Vivier wrote: > When we hot unplug a virtserialport and then try to hot plug again, > it fails: > > (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait > (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ > chardev=serial0,id=serial0,name=serial0 > (qemu) device_del serial0 > (qemu)

Hello Rusty, This patch updates the virtio spec (0.8.6) with the new ABI information for virtio-console. Please apply. --- virtio-spec-0.8.6.lyx 2010-04-16 12:06:13.416075709 +0530 +++ virtio-spec-0.8.6-virtio-console.lyx 2010-04-16 12:41:54.656201703 +0530 @@ -36,7 +36,7 @@ \paperpagestyle default \tracking_changes true \output_changes false -\author "" +\author "Amit

Hello Rusty, This patch updates the virtio spec (0.8.6) with the new ABI information for virtio-console. Please apply. --- virtio-spec-0.8.6.lyx 2010-04-16 12:06:13.416075709 +0530 +++ virtio-spec-0.8.6-virtio-console.lyx 2010-04-16 12:41:54.656201703 +0530 @@ -36,7 +36,7 @@ \paperpagestyle default \tracking_changes true \output_changes false -\author "" +\author "Amit

On Tue, Dec 03, 2019 at 03:46:50PM +0100, Amit Shah wrote: > On Thu, 2019-11-14 at 13:25 +0100, Laurent Vivier wrote: > > When we hot unplug a virtserialport and then try to hot plug again, > > it fails: > > > > (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait > > (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ > >

Turns out virtio console tries to take a buffer out of an active vq. Works by sheer luck, and is explicitly forbidden by spec. And while going over it I saw that error handling is also broken - failure is easy to trigger if I force allocations to fail. Lightly tested. Michael S. Tsirkin (6): virtio_console: don't tie bufs to a vq virtio: add ability to iterate over vqs virtio_console:

Turns out virtio console tries to take a buffer out of an active vq. Works by sheer luck, and is explicitly forbidden by spec. And while going over it I saw that error handling is also broken - failure is easy to trigger if I force allocations to fail. Lightly tested. Michael S. Tsirkin (6): virtio_console: don't tie bufs to a vq virtio: add ability to iterate over vqs virtio_console:

On Wed, Nov 13, 2019 at 10:21:11AM -0500, Michael S. Tsirkin wrote: > On Wed, Nov 13, 2019 at 04:00:56PM +0100, Laurent Vivier wrote: > > When we hot unplug a virtserialport and then try to hot plug again, > > it fails: > > > > (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait > > (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ >

On Wed, Nov 13, 2019 at 10:21:11AM -0500, Michael S. Tsirkin wrote: > On Wed, Nov 13, 2019 at 04:00:56PM +0100, Laurent Vivier wrote: > > When we hot unplug a virtserialport and then try to hot plug again, > > it fails: > > > > (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait > > (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ >

Hey Rusty, These are the patches that rework a few bits to make hot-unplug while ports are open not crash apps (or kernels). The problem is when hot-unplug is performed when a port is open, the cdev struct is kept around by the file pointers and when the app later does a 'close', things go boom-boom. This patch series makes sure port as well as device hot-unplug is now safe to perform