From: Alexander Graf Date: Wed, 24 Mar 2010 20:48:37 +0000 (+0100) Subject: KVM: PPC: Disable MSR_FEx for Cell hosts X-Git-Tag: v2.6.35-rc1~436^2~116 X-Git-Url: http://ftp.safe.ca/?a=commitdiff_plain;h=05b0ab1c0bb526ac1056bab356ee92cfd6daa6fd;p=safe%2Fjmp%2Flinux-2.6 KVM: PPC: Disable MSR_FEx for Cell hosts Cell can't handle MSR_FE0 and MSR_FE1 too well. It gets dog slow. So let's just override the guest whenever we see one of the two and mask them out. See commit ddf5f75a16b3e7460ffee881795aa168dffcd0cf for reference. Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index ed57584..41c23b6 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -357,6 +357,10 @@ void kvmppc_set_pvr(struct kvm_vcpu *vcpu, u32 pvr) !strcmp(cur_cpu_spec->platform, "ppc970")) vcpu->arch.hflags |= BOOK3S_HFLAG_DCBZ32; + /* Cell performs badly if MSR_FEx are set. So let's hope nobody + really needs them in a VM on Cell and force disable them. */ + if (!strcmp(cur_cpu_spec->platform, "ppc-cell-be")) + to_book3s(vcpu)->msr_mask &= ~(MSR_FE0 | MSR_FE1); } /* Book3s_32 CPUs always have 32 bytes cache line size, which Linux assumes. To