| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1175438139530-git-send-email-avi@qumranet.com> Date: Sun, 1 Apr 2007 17:35:20 +0300 From: Avi Kivity <avi@...ranet.com> To: kvm-devel@...ts.sourceforge.net Cc: linux-kernel@...r.kernel.org, Avi Kivity <avi@...ranet.com> Subject: [PATCH 23/41] KVM: Workaround vmx inability to virtualize the reset state The reset state has cs.selector == 0xf000 and cs.base == 0xffff0000, which aren't compatible with vm86 mode, which is used for real mode virtualization. When we create a vcpu, we set cs.base to 0xf0000, but if we get there by way of a reset, the values are inconsistent and vmx refuses to enter guest mode. Workaround by detecting the state and munging it appropriately. Signed-off-by: Avi Kivity <avi@...ranet.com> --- drivers/kvm/vmx.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 0d9bf0b..aa7e2ba 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -712,6 +712,8 @@ static void enter_rmode(struct kvm_vcpu *vcpu) vmcs_write32(GUEST_CS_AR_BYTES, 0xf3); vmcs_write32(GUEST_CS_LIMIT, 0xffff); + if (vmcs_readl(GUEST_CS_BASE) == 0xffff0000) + vmcs_writel(GUEST_CS_BASE, 0xf0000); vmcs_write16(GUEST_CS_SELECTOR, vmcs_readl(GUEST_CS_BASE) >> 4); fix_rmode_seg(VCPU_SREG_ES, &vcpu->rmode.es); -- 1.5.0.5 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists