> -----Original Message----- > From: Andrew Rybchenko <andrew.rybche...@oktetlabs.ru> > Sent: Monday, August 23, 2021 5:57 PM > To: Xueming(Steven) Li <xuemi...@nvidia.com> > Cc: dev@dpdk.org; Maxime Coquelin <maxime.coque...@redhat.com>; Chenbo Xia > <chenbo....@intel.com> > Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset > > On 8/23/21 9:39 AM, Xueming Li wrote: > > According to virtio spec, the device MUST reset when 0 is written to > > device_status, and present a 0 in device_status once that is done. > > > > This patch adds the missing part of waiting status 0 in reset function. > > > > Signed-off-by: Xueming Li <xuemi...@nvidia.com> > > --- > > drivers/net/virtio/virtio.c | 7 +++++-- > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c > > index 7e1e77797f..f003f612d6 100644 > > --- a/drivers/net/virtio/virtio.c > > +++ b/drivers/net/virtio/virtio.c > > @@ -3,6 +3,8 @@ > > * Copyright(c) 2020 Red Hat, Inc. > > */ > > > > +#include <unistd.h> > > + > > #include "virtio.h" > > > > uint64_t > > @@ -39,8 +41,9 @@ void > > virtio_reset(struct virtio_hw *hw) > > { > > VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET); > > - /* flush status write */ > > - VIRTIO_OPS(hw)->get_status(hw); > > + /* Flush status write and wait device ready. */ > > + while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET) > > + usleep(1000L); > > Don't we need a protection against forever loop here?
Good question, ideally we need, kernel driver function vp_reset() seems to have same issue. How about leaving an error message before return? > > > } > > > > void > >