From 7ef3ae82a6ebbf4750967d1ce43bcdb7e44ff74b Mon Sep 17 00:00:00 2001 From: Alex Zenla Date: Tue, 19 Nov 2024 21:16:33 +0000 Subject: [PATCH] 9p/xen: fix init sequence Large amount of mount hangs observed during hotplugging of 9pfs devices. The 9pfs Xen driver attempts to initialize itself more than once, causing the frontend and backend to disagree: the backend listens on a channel that the frontend does not send on, resulting in stalled processing. Only allow initialization of 9p frontend once. Fixes: c15fe55d14b3b ("9p/xen: fix connection sequence") Signed-off-by: Alex Zenla Signed-off-by: Alexander Merritt Signed-off-by: Ariadne Conill Reviewed-by: Juergen Gross Message-ID: <20241119211633.38321-1-alexander@edera.dev> Signed-off-by: Dominique Martinet --- net/9p/trans_xen.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index dfdbe1ca53387..0304e8a1616d8 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -465,6 +465,7 @@ static int xen_9pfs_front_init(struct xenbus_device *dev) goto error; } + xenbus_switch_state(dev, XenbusStateInitialised); return 0; error_xenbus: @@ -512,8 +513,10 @@ static void xen_9pfs_front_changed(struct xenbus_device *dev, break; case XenbusStateInitWait: - if (!xen_9pfs_front_init(dev)) - xenbus_switch_state(dev, XenbusStateInitialised); + if (dev->state != XenbusStateInitialising) + break; + + xen_9pfs_front_init(dev); break; case XenbusStateConnected: -- 2.39.5