On 07/23/2018 10:42 AM, Andrew Cooper wrote: > Because of a bug in 2010, LMSL support didn't functioned in Xen. > > c/s f2c608444 noticed but avoided fixing the issue for migration reasons. In > addition to migration problems, changes to the segmentation logic for > emulation would be needed before the feature could be enabled. > > This feature is entirely unused by operating systems (probably owing to its > semantics which only cover half the segment registers), and no one has > commented on its absence from Xen. As supporting it would involve a large > amount of effort, it seems better to remove the code entirely. > > If someone finds a valid usecase, we can resurrecting the code and > implementing the remaining parts, but I doubt anyone will. > > Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com> > --- > CC: Jan Beulich <jbeul...@suse.com> > CC: Boris Ostrovsky <boris.ostrov...@oracle.com> > CC: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> > CC: Brian Woods <brian.wo...@amd.com> > CC: Wei Liu <wei.l...@citrix.com> > CC: Roger Pau Monné <roger....@citrix.com> > CC: Sergey Dyasli <sergey.dya...@citrix.com> > --- > xen/arch/x86/hvm/hvm.c | 3 --- > xen/arch/x86/hvm/svm/svm.c | 23 ----------------------- > xen/arch/x86/pv/emul-priv-op.c | 2 +- > xen/include/asm-x86/hvm/hvm.h | 1 - > xen/include/asm-x86/msr-index.h | 4 +--- > 5 files changed, 2 insertions(+), 31 deletions(-) > > diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c > index c099c61..67b99af 100644 > --- a/xen/arch/x86/hvm/hvm.c > +++ b/xen/arch/x86/hvm/hvm.c > @@ -925,9 +925,6 @@ const char *hvm_efer_valid(const struct vcpu *v, uint64_t > value, > if ( (value & EFER_SVME) && (!p->extd.svm || !nestedhvm_enabled(d)) ) > return "SVME without nested virt"; > > - if ( (value & EFER_LMSLE) && !cpu_has_lmsl ) > - return "LMSLE without support"; > -
So we are silently dropping the bit? Should we still warn? -boris > if ( (value & EFER_FFXSE) && !p->extd.ffxsr ) > return "FFXSE without feature"; > _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
