This is a note to let you know that I've just added the patch titled s390/kvm: dont announce RRBM support to the 3.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: s390-kvm-dont-announce-rrbm-support.patch and it can be found in the queue-3.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 511c73bcf8e747cc95925a311dfeb630989db5a6 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger <borntraeger@xxxxxxxxxx> Date: Tue, 2 Oct 2012 16:25:38 +0200 Subject: s390/kvm: dont announce RRBM support From: Christian Borntraeger <borntraeger@xxxxxxxxxx> 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 [...] CC: Alex Graf <agraf@xxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> Cc: Qiang Huang <h.huangqiang@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kvm/kvm-s390.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -904,7 +904,7 @@ static int __init kvm_s390_init(void) } memcpy(facilities, S390_lowcore.stfle_fac_list, 16); facilities[0] &= 0xff00fff3f47c0000ULL; - facilities[1] &= 0x201c000000000000ULL; + facilities[1] &= 0x001c000000000000ULL; return 0; } Patches currently in stable-queue which might be from borntraeger@xxxxxxxxxx are queue-3.4/kvm-s390-move-kvm_guest_enter-exit-closer-to-sie.patch queue-3.4/s390-kvm-dont-announce-rrbm-support.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html