Commit f4bf56fb authored by Jay Zhou's avatar Jay Zhou Committed by Michael S. Tsirkin
Browse files

vhost: remove assertion to prevent crash 



QEMU will assert on vhost-user backed virtio device hotplug if QEMU is
using more RAM regions than VHOST_MEMORY_MAX_NREGIONS (for example if
it were started with a lot of DIMM devices).

Fix it by returning error instead of asserting and let callers of
vhost_set_mem_table() handle error condition gracefully.

Cc: qemu-stable@nongnu.org
Signed-off-by: default avatarIgor Mammedov <imammedo@redhat.com>
Signed-off-by: default avatarJay Zhou <jianjay.zhou@huawei.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 69aff030

hw/virtio/vhost-user.c

+4 −1
Original line number Diff line number Diff line
@@ -342,11 +342,14 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, 
                                     &offset);

        fd = memory_region_get_fd(mr);

        if (fd > 0) {

            if (fd_num == VHOST_MEMORY_MAX_NREGIONS) {

                error_report("Failed preparing vhost-user memory table msg");

                return -1;

            }

            msg.payload.memory.regions[fd_num].userspace_addr = reg->userspace_addr;

            msg.payload.memory.regions[fd_num].memory_size  = reg->memory_size;

            msg.payload.memory.regions[fd_num].guest_phys_addr = reg->guest_phys_addr;

            msg.payload.memory.regions[fd_num].mmap_offset = offset;

            assert(fd_num < VHOST_MEMORY_MAX_NREGIONS);

            fds[fd_num++] = fd;

        }

    }