dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

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

commit 9ff4cfb3fc ([S390] kvm-390: Let
kernel exit SIE instruction on work) fixed a problem of commit
commit cd3b70f5d4 ([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: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Christian Borntraeger 2011-06-06 14:14:38 +02:00 committed by Martin Schwidefsky
parent 59c5f46fbe
commit a578b37cc2
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/s390/kvm/sie64a.S
View File

@ -93,4 +93,6 @@ sie_err:
.section __ex_table,"a"
.quad sie_inst,sie_err
.quad sie_exit,sie_err
.quad sie_reenter,sie_err
.previous