search for: can_sleep

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 stack like this: WARNING: CPU: 3 PID: 121 at ./include/linux/dma-mapping.h:433 free_buf+0x1a8/0x288 Call Tra...

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 stack like this: WARNING: CPU: 3 PID: 121 at ./include/linux/dma-mapping.h:433 free_buf+0x1a8/0x288 Call Tra...

...ut_vq); - spin_unlock_irq(&port->outvq_lock); - if (buf) - free_buf(buf, true); - } while (buf); } /* @@ -1791,13 +1768,24 @@ static void control_work_handler(struct work_struct *work) spin_unlock(&portdev->c_ivq_lock); } +static void flush_bufs(struct virtqueue *vq, bool can_sleep) +{ + struct port_buffer *buf; + unsigned int len; + + while ((buf = virtqueue_get_buf(vq, &len))) + free_buf(buf, can_sleep); +} + static void out_intr(struct virtqueue *vq) { struct port *port; port = find_port_by_vq(vq->vdev->priv, vq); - if (!port) + if (!port) { + flush_buf...

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 (Tue) 11 Oct 2016 [12:05:15], Matt Redfearn wrote: > 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 stack like this: > > WARNING: CPU: 3 PID: 121 at ./include/linux/dma-mapping.h:433 >...

This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. NOTE: These two patches are identical to first two patches of the V8 patch-set, but are rebased to

This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. NOTE: These two patches are identical to first two patches of the V8 patch-set, but are rebased to

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. Changes since v7: - Rebased to

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. Changes since v7: - Rebased to

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. This patch-set is a rework of the

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces a new virtio type "rproc_serial" for communicating with remote processors over shared memory. The driver depends on the the remoteproc framework. As preparation for introducing "rproc_serial" I've done a refactoring of the transmit buffer handling. This patch-set is a rework of the

This is a rebase/resend of earlier patches. I skipped the pure cosmetic patches for now. Mostly this is consolidation earlier changes, removing dead code etc. The important part is the change for allowing a vmbus channel to get callback directly in interrupt mode; this is necessary for NAPI support. Stephen Hemminger (14): vmbus: use kernel bitops for traversing interrupt mask vmbus: drop

This is a rebase/resend of earlier patches. I skipped the pure cosmetic patches for now. Mostly this is consolidation earlier changes, removing dead code etc. The important part is the change for allowing a vmbus channel to get callback directly in interrupt mode; this is necessary for NAPI support. Stephen Hemminger (14): vmbus: use kernel bitops for traversing interrupt mask vmbus: drop