similar to: [PATCH] virtio: console: Don't access vqs if device was unplugged

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add a virtio remoteproc serial driver: VIRTIO_ID_RPROC_SERIAL (0xB) for communicating with a remote processor in an asymmetric multi-processing configuration. The virtio remoteproc serial driver reuses the existing virtio_console implementation, and adds support for DMA allocation of data buffers but disables support for tty

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add a virtio remoteproc serial driver: VIRTIO_ID_RPROC_SERIAL (0xB) for communicating with a remote processor in an asymmetric multi-processing configuration. The virtio remoteproc serial driver reuses the existing virtio_console implementation, and adds support for DMA allocation of data buffers but disables support for tty

A crash was observed when a device gets removed while a port is in use. When the port gets removed, we tried to free vq buffers. The vq no longer exists at this stage, just ensure we don't access it. The second patch fixes a warning where the pci region is already freed. I'm not sure what or how the region gets freed, any clues there will be helpful. Thanks, Amit Amit Shah (2):

A crash was observed when a device gets removed while a port is in use. When the port gets removed, we tried to free vq buffers. The vq no longer exists at this stage, just ensure we don't access it. The second patch fixes a warning where the pci region is already freed. I'm not sure what or how the region gets freed, any clues there will be helpful. Thanks, Amit Amit Shah (2):

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> 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

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> 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

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add a simple serial connection driver called VIRTIO_ID_RPROC_SERIAL (0xB) 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

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add a simple serial connection driver called VIRTIO_ID_RPROC_SERIAL (0xB) 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

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add feature VIRTIO_CONSOLE_F_DMA_MEM. If the architecture has DMA support and this feature bit is set, the virtio data buffers will be allocated from DMA memory. If the device requests the feature VIRTIO_CONSOLE_F_DMA_MEM, but the architecture don't support DMA the driver's probe function will fail. This is needed for using

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add feature VIRTIO_CONSOLE_F_DMA_MEM. If the architecture has DMA support and this feature bit is set, the virtio data buffers will be allocated from DMA memory. If the device requests the feature VIRTIO_CONSOLE_F_DMA_MEM, but the architecture don't support DMA the driver's probe function will fail. This is needed for using

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add feature VIRTIO_CONSOLE_F_DMA_MEM. If the architecture has DMA support and this feature bit is set, the virtio data buffers will be allocated from DMA memory. This is needed for using virtio_console from the remoteproc framework. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> cc: Rusty Russell <rusty

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add feature VIRTIO_CONSOLE_F_DMA_MEM. If the architecture has DMA support and this feature bit is set, the virtio data buffers will be allocated from DMA memory. This is needed for using virtio_console from the remoteproc framework. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> cc: Rusty Russell <rusty

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)

Commit c6017e793b93 ("virtio: console: add locks around buffer removal in port unplug path") added locking around the freeing of buffers in the vq. However, when free_buf() is called with can_sleep = true and rproc is enabled, it calls dma_free_coherent() directly, requiring interrupts to be enabled. Currently a WARNING is triggered due to the spin locking around free_buf, with a call

Commit c6017e793b93 ("virtio: console: add locks around buffer removal in port unplug path") added locking around the freeing of buffers in the vq. However, when free_buf() is called with can_sleep = true and rproc is enabled, it calls dma_free_coherent() directly, requiring interrupts to be enabled. Currently a WARNING is triggered due to the spin locking around free_buf, with a call

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,\ > >

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,\

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> 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

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> 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