From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56105) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cttxh-000372-5I for qemu-devel@nongnu.org; Fri, 31 Mar 2017 06:39:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cttxe-00086X-0v for qemu-devel@nongnu.org; Fri, 31 Mar 2017 06:39:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56896) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cttxd-00086D-RG for qemu-devel@nongnu.org; Fri, 31 Mar 2017 06:39:17 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 730E6C0567B5 for ; Fri, 31 Mar 2017 10:39:16 +0000 (UTC) Date: Fri, 31 Mar 2017 11:39:11 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170331103911.GB4514@work-vm> References: <20170331102521.29253-1-kraxel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170331102521.29253-1-kraxel@redhat.com> Subject: Re: [Qemu-devel] [PATCH] xhci: flush dequeue pointer to endpoint context List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: qemu-devel@nongnu.org * Gerd Hoffmann (kraxel@redhat.com) wrote: > When done processing a endpoint ring we must update the dequeue pointer > in the endpoint context in guest memory. This is needed to make sure > the guest has a correct view of things and also to make live migration > work properly, because xhci post_load restores alot of the state from > xhci data structures in guest memory. > > Add xhci_set_ep_state() call to do that. > > The recursive calls stopped by commit > ddb603ab6c981c1d67cb42266fc700c33e5b2d8f had the (unintentional) side > effect to hiding this bug. xhci_set_ep_state() was called before > processing, to set the state to running, which updated the dequeue > pointer too. > > Reported-by: Dr. David Alan Gilbert > Signed-off-by: Gerd Hoffmann Tested-by: Dr. David Alan Gilbert Thanks, that passes the basic test reported in the bz; boot the VM, lsblk, migrate, fdisk -l Dave > --- > hw/usb/hcd-xhci.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c > index 8958f95..a6929e5 100644 > --- a/hw/usb/hcd-xhci.c > +++ b/hw/usb/hcd-xhci.c > @@ -2063,7 +2063,7 @@ static void xhci_kick_ep(XHCIState *xhci, unsigned int slotid, > static void xhci_kick_epctx(XHCIEPContext *epctx, unsigned int streamid) > { > XHCIState *xhci = epctx->xhci; > - XHCIStreamContext *stctx; > + XHCIStreamContext *stctx = NULL; > XHCITransfer *xfer; > XHCIRing *ring; > USBEndpoint *ep = NULL; > @@ -2192,6 +2192,8 @@ static void xhci_kick_epctx(XHCIEPContext *epctx, unsigned int streamid) > break; > } > } > + /* update ring dequeue ptr */ > + xhci_set_ep_state(xhci, epctx, stctx, epctx->state); > epctx->kick_active--; > > ep = xhci_epid_to_usbep(epctx); > -- > 2.9.3 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK