KVM: SVM: Move spec control call after restore of GS
authorThomas Gleixner <tglx@linutronix.de>
Fri, 11 May 2018 13:21:01 +0000 (15:21 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 22 May 2018 14:58:02 +0000 (16:58 +0200)
commit69e9b0b1e04001a743927489bb8b9a10344810d8
tree7c883daa3088458e60776504d0ad19bf6d5494ba
parent3a684641619ff0e06b8d4cb8c2ffbef304c9bdb1
KVM: SVM: Move spec control call after restore of GS

commit 15e6c22fd8e5a42c5ed6d487b7c9fe44c2517765 upstream

svm_vcpu_run() invokes x86_spec_ctrl_restore_host() after VMEXIT, but
before the host GS is restored. x86_spec_ctrl_restore_host() uses 'current'
to determine the host SSBD state of the thread. 'current' is GS based, but
host GS is not yet restored and the access causes a triple fault.

Move the call after the host GS restore.

Fixes: 885f82bfbc6f x86/process: Allow runtime control of Speculative Store Bypass
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kvm/svm.c