[Xen-changelog] [xen stable-4.8] x86/vmx: Avoid hitting BUG_ON() after EPTP-related domain_crash()

[patchbot@xxxxxxx]

commit 21ac6c8e446ee6742e2e839b56d94617a6930b16
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Fri Sep 14 13:33:20 2018 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Fri Sep 14 13:33:20 2018 +0200

    x86/vmx: Avoid hitting BUG_ON() after EPTP-related domain_crash()
    
    If the EPTP pointer can't be located in the altp2m list, the domain
    is (legitimately) crashed.
    
    Under those circumstances, execution will continue and guarentee to hit the
    BUG_ON(idx >= MAX_ALTP2M) (unfortunately, just out of context).
    
    Return from vmx_vmexit_handler() after the domain_crash(), which also has 
the
    side effect of reentering the scheduler more promptly.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Razvan Cojocaru <rcojocaru@xxxxxxxxxxxxxxx>
    Acked-by: Kevin Tian <kevin.tian@xxxxxxxxx>
    master commit: 48dbb2dbe9d9f92a2890a15bb48a0598c065b9f8
    master date: 2018-08-02 10:10:43 +0100
---
 xen/arch/x86/hvm/vmx/vmx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 37f6211b15..9652de32e2 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -3534,6 +3534,8 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
             {
                 gdprintk(XENLOG_ERR, "EPTP not found in alternate p2m list\n");
                 domain_crash(v->domain);
+
+                return;
             }
         }
 
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.8

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