On 07/23/2018 06:02 PM, Boris Ostrovsky wrote: > 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?
Nevermind. Reviewed-by: Boris Ostrovsky <boris.ostrov...@oracle.com> > > -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
