Commit a578b37c authored by Christian Borntraeger's avatar Christian Borntraeger Committed by Martin Schwidefsky

[S390] kvm-s390: Fix host crash on misbehaving guests

commit 9ff4cfb3 ([S390] kvm-390: Let
kernel exit SIE instruction on work) fixed a problem of commit
commit cd3b70f5 ([S390] virtualization
aware cpu measurement) but uncovered another one.

If a kvm guest accesses guest real memory that doesnt exist, the
page fault handler calls the sie hook, which then rewrites
the return psw from sie_inst to either sie_exit or sie_reenter.
On return, the page fault handler will then detect the wrong access
as a kernel fault causing a kernel oops in sie_reenter or sie_exit.

We have to add these two addresses to the exception  table to allow
graceful exits.
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 59c5f46f
...@@ -93,4 +93,6 @@ sie_err: ...@@ -93,4 +93,6 @@ sie_err:
.section __ex_table,"a" .section __ex_table,"a"
.quad sie_inst,sie_err .quad sie_inst,sie_err
.quad sie_exit,sie_err
.quad sie_reenter,sie_err
.previous .previous
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