LLM was Claude Opus 5, agent was Quality Playbook <https://github.com/andrewstellman/quality-playbook>, an open-source code quality agent I maintain.
One request: unless your version is already queued, would you take a corrected patch from me so the commit keeps my authorship? Having an upstream Linux commit trace directly to a Quality Playbook finding would mean a lot for the project. On Mon, Sep 7, 2026 at 5:45 PM Michael S. Tsirkin <[email protected]> wrote: > > On Fri, Sep 04, 2026 at 10:13:18AM -0400, Andrew Stellman wrote: > > vp_interrupt() reads the ISR before dispatching config-change and > > vring handling. Reading the ISR also clears it, so once the read > > returns non-zero the interrupt was from this device and has already > > been consumed. > > > > Currently vp_interrupt() returns the result of vp_vring_interrupt(). > > For a config-change interrupt with no vring work, that can return > > IRQ_NONE even though the ISR was non-zero and the interrupt was > > handled. > > > > Call vp_vring_interrupt() for any queue work, but once the ISR is > > non-zero return IRQ_HANDLED. > > > > Tested with QEMU virtio-blk-pci forced to INTx using vectors=0 and > > pci=nomsi. On an idle device, 200 config-change interrupts were > > generated using QMP block_resize. > > > > Before this change, irq_handler_exit reported ret=unhandled and > > /proc/irq/11/spurious increased from 0 to 200 unhandled interrupts. > > After this change, irq_handler_exit reported ret=handled and the > > unhandled count remained at 0. > > > > The issue was found during an LLM-assisted Quality Playbook review. > > > > Fixes: 77cf524654a8 ("virtio_pci: split up vp_interrupt") > > Suggested-by: Michael S. Tsirkin <[email protected]> > > Assisted-by: LLM > > tell us which llm and which agent pls > > > Signed-off-by: Andrew Stellman <[email protected]> > > --- > > Changes from v2: > > - Repost as a standalone patch in a new thread, per maintainer request. > > - Add LLM-assistance disclosure. > > - No code changes. > > > > Changes from v1: > > - Return IRQ_HANDLED for any non-zero ISR, as suggested by Michael. > > - Add Fixes and Suggested-by tags. > > - Test the change with virtio-blk forced to legacy INTx under QEMU. > > > > Full red/green test logs and the tested v2 patch: > > https://github.com/andrewstellman/quality-playbook/tree/11ba61d/evidence/virtio-pci-intx > > > > drivers/virtio/virtio_pci_common.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/virtio/virtio_pci_common.c > > b/drivers/virtio/virtio_pci_common.c > > index 10371ecbc054..b90c174450b2 100644 > > --- a/drivers/virtio/virtio_pci_common.c > > +++ b/drivers/virtio/virtio_pci_common.c > > @@ -120,7 +120,9 @@ static irqreturn_t vp_interrupt(int irq, void *opaque) > > if (isr & VIRTIO_PCI_ISR_CONFIG) > > vp_config_changed(irq, opaque); > > > > - return vp_vring_interrupt(irq, opaque); > > + vp_vring_interrupt(irq, opaque); > > + > > + return IRQ_HANDLED; > > } > > > > static int vp_request_msix_vectors(struct virtio_device *vdev, int > > nvectors, > > base-commit: bc35965f6940a9bf834d54187b6088b8eb09206d > > > > -- > > 2.43.0 >
