From patchwork Fri Mar 2 14:12:33 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: PPC: Don't sync timebase when inside VM Date: Fri, 02 Mar 2012 04:12:33 -0000 From: Alexander Graf X-Patchwork-Id: 144267 Message-Id: <1330697553-27156-1-git-send-email-agraf@suse.de> To: kvm-ppc@vger.kernel.org Cc: kvm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Scott Wood , Stuart Yoder When running inside a virtual machine, we can not modify timebase, so let's just not call the functions for it then. This resolves hangs when booting e500 SMP guests on overcommitted hosts. Reported-by: Stuart Yoder Signed-off-by: Alexander Graf --- arch/powerpc/platforms/85xx/smp.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c index ff42490..d4b6c1f 100644 --- a/arch/powerpc/platforms/85xx/smp.c +++ b/arch/powerpc/platforms/85xx/smp.c @@ -249,6 +249,13 @@ void __init mpc85xx_smp_init(void) smp_85xx_ops.cause_ipi = doorbell_cause_ipi; } + /* When running under a hypervisor, we can not modify tb */ + np = of_find_node_by_path("/hypervisor"); + if (np) { + smp_85xx_ops.give_timebase = NULL; + smp_85xx_ops.take_timebase = NULL; + } + smp_ops = &smp_85xx_ops; #ifdef CONFIG_KEXEC