drivers: serial: Fix deadlock in virtio console #97335
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added 3 commits
October 8, 2025 13:08
…sages There was a bug in the VIRTIO Console driver which could cause a deadlock by attempting to add buffers to the control-tx virtqueue too fast and with an infinite timeout. This commit fixes it by placing messages that couldn't be sent in a FIFO queue and taking care of them later in a callback function. Signed-off-by: Jakub Klimczak <[email protected]>
Add descriptions to the Kconfig file and restructure it slightly. Signed-off-by: Jakub Klimczak <[email protected]>
Spinlocks in functions virtconsole_control_recv_cb and virtconsole_send_control_msg were unnecessary since those were called from virtio_pci_isr or virtio_mmio_isr, which already use spinlocks. Signed-off-by: Jakub Klimczak <[email protected]>
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dcpleung
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Oct 10, 2025
fkokosinski
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This PR fixes a deadlock occurring in some cases due to the infinite wait time in
virtq_add_buffer_chaincalled from the isr callback. Its fixed by changing the timeout toK_NO_WAITand delaying adding buffers to the virtqueue if no free descriptors are available