On Mon, Jul 01, 2024 at 04:14:35PM +0100, Alex Bennée wrote: > "BillXiang" <xiangwench...@dayudpu.com> writes: > > >> From: "Alex Bennée"<alex.ben...@linaro.org> > >> Date: Mon, Jul 1, 2024, 16:49 > >> Subject: Re: [PATCH] vhost-user: Skip unnecessary duplicated > >> VHOST_USER_SET_LOG_BASE requests > >> To: "项文成"<xiangwench...@dayudpu.com> > >> Cc: <qemu-devel@nongnu.org>, <m...@redhat.com> > >> 项文成 <xiangwench...@dayudpu.com> writes: > >> > >> > From: BillXiang <xiangwench...@dayudpu.com> > >> > > >> > The VHOST_USER_SET_LOG_BASE requests should be categorized into > >> > non-vring specific messages, and should be sent only once. > >> > If send more than once, dpdk will munmap old log_addr which may has > >> > been used and cause segmentation fault. > >> > >> This looks fine to me but looking at the vhost-user.rst we don't seem to > >> make any explicit statements about how many times given messages should > >> be sent. > >> > > There is indeed no explicit statements about how many times given messages > > should be sent in vhost-user.rst but already have some discussions such as > > https://lore.kernel.org/qemu-devel/20230127083027-mutt-send-email-...@kernel.org/. > > Right, but I think we should then update the specification if this is > the way we want things to work. Otherwise we are putting a backend > specific hack that another backend might be able to tolerate.
I think it's a dpdk bug, we *allow* resending same message many times. However, less messages is better, I don't see a reason to repeat the same message many times. > >> > > >> > Signed-off-by: BillXiang <xiangwench...@dayudpu.com> > >> > --- > >> > hw/virtio/vhost-user.c | 1 + > >> > 1 file changed, 1 insertion(+) > >> > > >> > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > >> > index cdf9af4a4b..41e34edd49 100644 > >> > --- a/hw/virtio/vhost-user.c > >> > +++ b/hw/virtio/vhost-user.c > >> > @@ -371,6 +371,7 @@ static bool > >> > vhost_user_per_device_request(VhostUserRequest request) > >> > case VHOST_USER_RESET_DEVICE: > >> > case VHOST_USER_ADD_MEM_REG: > >> > case VHOST_USER_REM_MEM_REG: > >> > + case VHOST_USER_SET_LOG_BASE: > >> > return true; > >> > default: > >> > return false; > >> > >> -- > >> Alex Bennée > >> Virtualisation Tech Lead @ Linaro > > -- > Alex Bennée > Virtualisation Tech Lead @ Linaro
