[xen stable-4.16] argo: Remove reachable ASSERT_UNREACHABLE

[patchbot@xxxxxxx]

commit d4a11d6a22cf73ac7441750e5e8113779348885e
Author:     Jason Andryuk <jandryuk@xxxxxxxxx>
AuthorDate: Mon Oct 31 13:21:31 2022 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Oct 31 13:21:31 2022 +0100

    argo: Remove reachable ASSERT_UNREACHABLE
    
    I observed this ASSERT_UNREACHABLE in partner_rings_remove consistently
    trip.  It was in OpenXT with the viptables patch applied.
    
    dom10 shuts down.
    dom7 is REJECTED sending to dom10.
    dom7 shuts down and this ASSERT trips for dom10.
    
    The argo_send_info has a domid, but there is no refcount taken on
    the domain.  Therefore it's not appropriate to ASSERT that the domain
    can be looked up via domid.  Replace with a debug message.
    
    Signed-off-by: Jason Andryuk <jandryuk@xxxxxxxxx>
    Reviewed-by: Christopher Clark <christopher.w.clark@xxxxxxxxx>
    master commit: 197f612b77c5afe04e60df2100a855370d720ad7
    master date: 2022-10-14 14:45:41 +0100
---
 xen/common/argo.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/common/argo.c b/xen/common/argo.c
index eaea7ba888..80f3275092 100644
--- a/xen/common/argo.c
+++ b/xen/common/argo.c
@@ -1298,7 +1298,8 @@ partner_rings_remove(struct domain *src_d)
                     ASSERT_UNREACHABLE();
             }
             else
-                ASSERT_UNREACHABLE();
+                argo_dprintk("%pd has entry for stale partner d%u\n",
+                             src_d, send_info->id.domain_id);
 
             if ( dst_d )
                 rcu_unlock_domain(dst_d);
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.16