| Message ID | 20190315092348.32613-1-andr2000@gmail.com (mailing list archive) |
|---|---|
| State | Rejected |
| Headers | show |
| Series | [Xen-devel] Input: xen-kbdfront - signal the backend that we disconnect | expand |
On 15/03/2019 10:23, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > While disconnecting from the backend we clean up shared resources > (event channel, ring buffer), but never let the backend know about > that. This may lead to inconsistent backend state and/or shared > resources use. > Fix this by explicitly letting the backend know that frontend has > destroyed shared resources by changing its Xen bus state accordingly. > > Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > --- > drivers/input/misc/xen-kbdfront.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c > index 24bc5c5d876f..ecb6e719e0e2 100644 > --- a/drivers/input/misc/xen-kbdfront.c > +++ b/drivers/input/misc/xen-kbdfront.c > @@ -488,6 +488,8 @@ static int xenkbd_connect_backend(struct xenbus_device *dev, > > static void xenkbd_disconnect_backend(struct xenkbd_info *info) > { > + xenbus_switch_state(info->xbdev, XenbusStateClosing); > + > if (info->irq >= 0) > unbind_from_irqhandler(info->irq, info); > info->irq = -1; > As already stated for the related netfront patch: I'm not sure this is really what we want. Have you tested xl save/restore or migration of the guest with your patch applied? Juergen
On 3/22/19 1:03 PM, Juergen Gross wrote: > On 15/03/2019 10:23, Oleksandr Andrushchenko wrote: >> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >> >> While disconnecting from the backend we clean up shared resources >> (event channel, ring buffer), but never let the backend know about >> that. This may lead to inconsistent backend state and/or shared >> resources use. >> Fix this by explicitly letting the backend know that frontend has >> destroyed shared resources by changing its Xen bus state accordingly. >> >> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >> --- >> drivers/input/misc/xen-kbdfront.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c >> index 24bc5c5d876f..ecb6e719e0e2 100644 >> --- a/drivers/input/misc/xen-kbdfront.c >> +++ b/drivers/input/misc/xen-kbdfront.c >> @@ -488,6 +488,8 @@ static int xenkbd_connect_backend(struct xenbus_device *dev, >> >> static void xenkbd_disconnect_backend(struct xenkbd_info *info) >> { >> + xenbus_switch_state(info->xbdev, XenbusStateClosing); >> + >> if (info->irq >= 0) >> unbind_from_irqhandler(info->irq, info); >> info->irq = -1; >> > As already stated for the related netfront patch: I'm not sure this > is really what we want. Have you tested xl save/restore or migration > of the guest with your patch applied? Well, it comes out that this is not enough and needs much more work, so please let's abandon this patch > > Juergen Thank you, Oleksandr
diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c index 24bc5c5d876f..ecb6e719e0e2 100644 --- a/drivers/input/misc/xen-kbdfront.c +++ b/drivers/input/misc/xen-kbdfront.c @@ -488,6 +488,8 @@ static int xenkbd_connect_backend(struct xenbus_device *dev, static void xenkbd_disconnect_backend(struct xenkbd_info *info) { + xenbus_switch_state(info->xbdev, XenbusStateClosing); + if (info->irq >= 0) unbind_from_irqhandler(info->irq, info); info->irq = -1;