| Message ID | 20221115132657.97864-1-roger.pau@citrix.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | amd/virt_ssbd: refactoring and fixes | expand |
On 15/11/2022 13:26, Roger Pau Monne wrote: > Hello, > > Just two patches remaining, and the last one is already Acked. > > First patch deals with moving the switching of SSBD from guest > vm{entry,exit} to vCPU context switch, and lets Xen run with the guest > SSBD selection under some circumstances by default. > > Andrew has expressed reservations to me privately with patch 2/2, but > I'm still sending it so that comments can be made publicly (or the patch > applied). > > Thanks, Roger. To avoid a further round trip, I've committed these patches with some minor non-functional adjustments. In patch 1, an expanded context switching comment, and in patch 2, an adjusted commit message and movement into __initdata. I've also closed out #90, which closes one of the release blockers. All other bugs can wait until 4.18, including the totally bizarre one where using cpuid="host:virt-ssbd=1" in the xl.cfg file causes IBRS to become hidden. I confirmed this was pre-existing behaviour, but haven't investigated further. ~Andrew
On Wed, Nov 16, 2022 at 12:27:29AM +0000, Andrew Cooper wrote: > On 15/11/2022 13:26, Roger Pau Monne wrote: > > Hello, > > > > Just two patches remaining, and the last one is already Acked. > > > > First patch deals with moving the switching of SSBD from guest > > vm{entry,exit} to vCPU context switch, and lets Xen run with the guest > > SSBD selection under some circumstances by default. > > > > Andrew has expressed reservations to me privately with patch 2/2, but > > I'm still sending it so that comments can be made publicly (or the patch > > applied). > > > > Thanks, Roger. > > To avoid a further round trip, I've committed these patches with some > minor non-functional adjustments. In patch 1, an expanded context > switching comment, and in patch 2, an adjusted commit message and > movement into __initdata. FWIW, I didn't expand the comment in patch 1 because I though it was likely to get out of sync. > I've also closed out #90, which closes one of the release blockers. > > All other bugs can wait until 4.18, including the totally bizarre one > where using cpuid="host:virt-ssbd=1" in the xl.cfg file causes IBRS to > become hidden. I confirmed this was pre-existing behaviour, but haven't > investigated further. Hm, I don't seem to be able to use cpuid="host:virt-ssbd=1", I get: # xl create -c tests/virt-spec/test-hvm32-virt-spec.cfg Parsing config from tests/virt-spec/test-hvm32-virt-spec.cfg while parsing CPUID string: "host:virt-ssbd=1": error: first word must be "host" However using cpuid=["0x80000008:ebx=xxxxxx1xxxxxxxxxxxxxxxxxxxxxxxxx"] does work and I can see both virt-ssbd and ibrs present in the guest CPUID on an EPYC 7543P (Milan). Regards, Roger.
Hello, Just two patches remaining, and the last one is already Acked. First patch deals with moving the switching of SSBD from guest vm{entry,exit} to vCPU context switch, and lets Xen run with the guest SSBD selection under some circumstances by default. Andrew has expressed reservations to me privately with patch 2/2, but I'm still sending it so that comments can be made publicly (or the patch applied). Thanks, Roger. Roger Pau Monne (2): amd/virt_ssbd: set SSBD at vCPU context switch amd: remove VIRT_SC_MSR_HVM synthetic feature docs/misc/xen-command-line.pandoc | 10 +++-- xen/arch/x86/cpu/amd.c | 56 ++++++++++++++------------ xen/arch/x86/cpuid.c | 9 +++-- xen/arch/x86/hvm/svm/entry.S | 6 --- xen/arch/x86/hvm/svm/svm.c | 45 ++++++++------------- xen/arch/x86/include/asm/amd.h | 1 + xen/arch/x86/include/asm/cpufeatures.h | 2 +- xen/arch/x86/include/asm/msr.h | 3 +- xen/arch/x86/msr.c | 9 +++++ xen/arch/x86/spec_ctrl.c | 8 ++-- 10 files changed, 75 insertions(+), 74 deletions(-)