Message ID | 20110410033616.GA4899@t400 (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi, Amos On 04/10/2011 11:36 AM, Amos Kong wrote: > Hi pekka, > > Does virtio-console work with kvm-tools? > It seems that virtio-console.vps[] is not initialized in virtio-console.c I guess you mean virtio-console.vqs[]. They are initialized here in virtio_console_pci_io_out when guest pings us. case VIRTIO_PCI_QUEUE_PFN: { struct virt_queue *queue; void *p; assert(console_device.queue_selector < VIRTIO_CONSOLE_NUM_QUEUES); queue = &console_device.vqs[console_device.queue_selector]; queue->pfn = ioport__read32(data); p = guest_flat_to_host(self, queue->pfn << 12); vring_init(&queue->vring, VIRTIO_CONSOLE_QUEUE_SIZE, p, 4096); break; } However, virtio_console__inject_interrupt tries to use virt queues before guest tell us to initialize them. I think that's why you got SIGSEGV and SIGFPE. Good catch! I am gonna fix it. > > > (gdb) r run -i linux-0.2.img -k ./vmlinuz-2.6.38-rc6+ -r ./initrd.img-2.6.38-rc6+ -p=init=1 -m 500 -c > Starting program: /project/rh/kvm-tools/tools/kvm/kvm run -i linux-0.2.img -k ./vmlinuz-2.6.38-rc6+ -r ./initrd.img-2.6.38-rc6+ -p=init=1 -m 500 -c > [Thread debugging using libthread_db enabled] > [New Thread 0x7fffd6e2d700 (LWP 19280)] > Warning: request type 8 > > Program received signal SIGSEGV, Segmentation fault. > 0x00000000004026ca in virt_queue__available (vq=0x60d3c8) at include/kvm/virtio.h:31 > 31 return vq->vring.avail->idx != vq->last_avail_idx; > (gdb) > (gdb) bt > #0 0x00000000004026ca in virt_queue__available (vq=0x60d3c8) at include/kvm/virtio.h:31 > #1 0x00000000004027f7 in virtio_console__inject_interrupt (self=0x68f010) at virtio-console.c:71 > #2 0x00000000004083b2 in handle_sigalrm (sig=14) at kvm-run.c:51 > #3 <signal handler called> > #4 0x00007ffff79bf283 in pthread_join () from /lib/libpthread.so.0 > #5 0x00000000004088bb in kvm_cmd_run (argc=0, argv=0x7fffffffdd18, prefix=0x0) at kvm-run.c:216 > #6 0x000000000040834e in handle_command (command=0x7fffffffdbb0, argc=11, argv=0x7fffffffdd10) at kvm-cmd.c:55 > #7 0x0000000000405bd5 in handle_kvm_command (argc=11, argv=0x7fffffffdd10) at main.c:16 > #8 0x0000000000405bfe in main (argc=12, argv=0x7fffffffdd08) at main.c:21 > (gdb) p *vq > $2 = {vring = {num = 0, desc = 0x0, avail = 0x0, used = 0x0}, pfn = 0, last_avail_idx = 0} > > ------- > > I added the check of vq->vring.avail in virt_queue__available(), but it also failed. > > diff --git a/tools/kvm/include/kvm/virtio.h b/tools/kvm/include/kvm/virtio.h > index 9f892a1..d3622b1 100644 > --- a/tools/kvm/include/kvm/virtio.h > +++ b/tools/kvm/include/kvm/virtio.h > @@ -28,6 +28,8 @@ static inline struct vring_desc *virt_queue__get_desc(struct virt_queue *queue, > > static inline bool virt_queue__available(struct virt_queue *vq) > { > + if (!vq->vring.avail) > + return -1; > return vq->vring.avail->idx != vq->last_avail_idx; > } > > (gdb) r run -i linux-0.2.img -k ./vmlinuz-2.6.38-rc6+ -r ./initrd.img-2.6.38-rc6+ -p=init=1 -m 500 -c > Starting program: /project/rh/kvm-tools/tools/kvm/kvm run -i linux-0.2.img -k ./vmlinuz-2.6.38-rc6+ -r ./initrd.img-2.6.38-rc6+ -p=init=1 -m 500 -c > [Thread debugging using libthread_db enabled] > [New Thread 0x7fffd6e2d700 (LWP 19434)] > Warning: request type 8 > > Program received signal SIGFPE, Arithmetic exception. > 0x00000000004066cd in virt_queue__pop (queue=0x60d3c8) at include/kvm/virtio.h:21 > 21 return queue->vring.avail->ring[queue->last_avail_idx++ % queue->vring.num]; > (gdb) bt > #0 0x00000000004066cd in virt_queue__pop (queue=0x60d3c8) at include/kvm/virtio.h:21 > #1 0x000000000040679c in virt_queue__get_iov (queue=0x60d3c8, iov=0x7fffffffcda0, out=0x7fffffffd5be, in=0x7fffffffd5bc, kvm=0x68f010) at virtio.c:21 > #2 0x000000000040284b in virtio_console__inject_interrupt (self=0x68f010) at virtio-console.c:72 > #3 0x00000000004083da in handle_sigalrm (sig=14) at kvm-run.c:51 > #4 <signal handler called> > #5 0x00007ffff79bf283 in pthread_join () from /lib/libpthread.so.0 > #6 0x00000000004088e3 in kvm_cmd_run (argc=0, argv=0x7fffffffdd18, prefix=0x0) at kvm-run.c:216 > #7 0x0000000000408376 in handle_command (command=0x7fffffffdbb0, argc=11, argv=0x7fffffffdd10) at kvm-cmd.c:55 > #8 0x0000000000405bfd in handle_kvm_command (argc=11, argv=0x7fffffffdd10) at main.c:16 > #9 0x0000000000405c26 in main (argc=12, argv=0x7fffffffdd08) at main.c:21 > (gdb) p *queue > $2 = {vring = {num = 0, desc = 0x0, avail = 0x0, used = 0x0}, pfn = 0, last_avail_idx = 0} > > > Amos. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
diff --git a/tools/kvm/include/kvm/virtio.h b/tools/kvm/include/kvm/virtio.h index 9f892a1..d3622b1 100644 --- a/tools/kvm/include/kvm/virtio.h +++ b/tools/kvm/include/kvm/virtio.h @@ -28,6 +28,8 @@ static inline struct vring_desc *virt_queue__get_desc(struct virt_queue *queue, static inline bool virt_queue__available(struct virt_queue *vq) { + if (!vq->vring.avail) + return -1; return vq->vring.avail->idx != vq->last_avail_idx; }