]> git.hungrycats.org Git - linux/commit
s390/kvm: dont announce RRBM support
authorChristian Borntraeger <borntraeger@de.ibm.com>
Tue, 2 Oct 2012 14:25:38 +0000 (16:25 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 17 Jan 2013 16:45:44 +0000 (08:45 -0800)
commita9234777b4cdf210360e085d267e70a40500e8ef
tree78eb5cdb418fc278b215e24e6319549078caf53b
parent99219d1135e9badaa08b18348aa44fd5772b39ea
s390/kvm: dont announce RRBM support

commit 87cac8f879a5ecd7109dbe688087e8810b3364eb upstream.

Newer kernels (linux-next with the transparent huge page patches)
use rrbm if the feature is announced via feature bit 66.
RRBM will cause intercepts, so KVM does not handle it right now,
causing an illegal instruction in the guest.
The  easy solution is to disable the feature bit for the guest.

This fixes bugs like:
Kernel BUG at 0000000000124c2a [verbose debug info unavailable]
illegal operation: 0001 [#1] SMP
Modules linked in: virtio_balloon virtio_net ipv6 autofs4
CPU: 0 Not tainted 3.5.4 #1
Process fmempig (pid: 659, task: 000000007b712fd0, ksp: 000000007bed3670)
Krnl PSW : 0704d00180000000 0000000000124c2a (pmdp_clear_flush_young+0x5e/0x80)
     R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
     00000000003cc000 0000000000000004 0000000000000000 0000000079800000
     0000000000040000 0000000000000000 000000007bed3918 000000007cf40000
     0000000000000001 000003fff7f00000 000003d281a94000 000000007bed383c
     000000007bed3918 00000000005ecbf8 00000000002314a6 000000007bed36e0
 Krnl Code:>0000000000124c2a: b9810025          ogr     %r2,%r5
           0000000000124c2e: 41343000           la      %r3,0(%r4,%r3)
           0000000000124c32: a716fffa           brct    %r1,124c26
           0000000000124c36: b9010022           lngr    %r2,%r2
           0000000000124c3a: e3d0f0800004       lg      %r13,128(%r15)
           0000000000124c40: eb22003f000c       srlg    %r2,%r2,63
[ 2150.713198] Call Trace:
[ 2150.713223] ([<00000000002312c4>] page_referenced_one+0x6c/0x27c)
[ 2150.713749]  [<0000000000233812>] page_referenced+0x32a/0x410
[...]

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: Alex Graf <agraf@suse.de>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/s390/kvm/kvm-s390.c