From: Paolo Bonzini Date: Mon, 18 Aug 2014 11:15:51 +0000 (+0200) Subject: KVM: x86: do not check CS.DPL against RPL during task switch X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9a4cfb27f7233610c5ddc82329c26d39683fad72;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git KVM: x86: do not check CS.DPL against RPL during task switch This reverts the check added by commit 5045b468037d (KVM: x86: check CS.DPL against RPL during task switch, 2014-05-15). Although the CS.DPL=CS.RPL check is mentioned in table 7-1 of the SDM as causing a #TSS exception, it is not mentioned in table 6-6 that lists "invalid TSS conditions" which cause #TSS exceptions. In fact it causes some tests to fail, which pass on bare-metal. Keep the rest of the commit, since we will find new uses for it in 3.18. Reported-by: Nadav Amit Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index ef117b842334..03954f7900f5 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1491,9 +1491,6 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt, goto exception; break; case VCPU_SREG_CS: - if (in_task_switch && rpl != dpl) - goto exception; - if (!(seg_desc.type & 8)) goto exception;