Only apply the software workaround on the models that might be
affected by MCE on page size change. For these models that are
known immune to the issue, the mitigation is turned off.
Atom processors are not afftected by the issue.
Also check the CPUID & MSR to check whether the model is immune to the issue:
CPU is not vulnerable when both CPUID.(EAX=07H,ECX=0H).EDX[29] and
IA32_ARCH_CAPABILITIES[IF_PSCHANGE_MC_NO] are 1.
Other cases not listed above, CPU may be vulnerable.
This patch also changes MACROs for MSR IA32_ARCH_CAPABILITIES bits to UL instead of U
since the MSR is 64bit.
Tracked-On: #4101
Signed-off-by: Binbin Wu <binbin.wu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
-- remove some unnecessary includes
-- fix a typo
-- remove unnecessary void before launch_vms
Tracked-On: #1842
Signed-off-by: Mingqiang Chi <mingqiang.chi@intel.com>
Microarchitectural Data Sampling (MDS) is a hardware vulnerability
which allows unprivileged speculative access to data which is available
in various CPU internal buffers.
1. Mitigation on ACRN:
1) Microcode update is required.
2) Clear CPU internal buffers (store buffer, load buffer and
load port) if current CPU is affected by MDS, when VM entry
to avoid any information leakage to guest thru above buffers.
3) Mitigation is not needed if ARCH_CAP_MDS_NO bit (bit5)
is set in IA32_ARCH_CAPABILITIES MSR (10AH), in this case,
current processor is no affected by MDS vulnerability, in other
cases mitigation for MDS is required.
2. Methods to clear CPU buffers (microcode update is required):
1) L1D cache flush
2) VERW instruction
Either of above operations will trigger clearing all
CPU internal buffers if this CPU is affected by MDS.
Above mechnism is enumerated by:
CPUID.(EAX=7H, ECX=0):EDX[MD_CLEAR=10].
3. Mitigation details on ACRN:
if (processor is affected by MDS)
if (processor is not affected by L1TF OR
L1D flush is not launched on VM Entry)
execute VERW instruction when VM entry.
endif
endif
4. Referrence:
Deep Dive: Intel Analysis of Microarchitectural Data Sampling
https://software.intel.com/security-software-guidance/insights/
deep-dive-intel-analysis-microarchitectural-data-sampling
Deep Dive: CPUID Enumeration and Architectural MSRs
https://software.intel.com/security-software-guidance/insights/
deep-dive-cpuid-enumeration-and-architectural-msrs
Tracked-On: #3317
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Reviewed-by: Anthony Xu <anthony.xu@intel.com>
Reviewed-by: Jason CJ Chen <jason.cj.chen@intel.com>
ACRN hypervisor always print CPU microcode update
warning message on KBL NUC platform, even after
BIOS was updated to the latest.
'check_cpu_security_cap()' returns false if
no ARCH_CAPABILITIES MSR support on current platform,
but this MSR may not be available on some platforms.
This patch is to remove this pre-condition.
Tracked-On: #3317
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Reviewed-by: Jason CJ Chen <jason.cj.chen@intel.com>
add get_ibrs_type API to get ibrs type.
this patch fix Misra C violation:
filename:/hypervisor/arch/x86/security.c function:None offset:19:
reason:Variable should be declared static. : ibrs_type
Tracked-On: #861
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
there are still some security related funcs in cpu_caps.c & cpu.c,
move them out into security.c.
Changes to be committed:
modified: Makefile
modified: arch/x86/cpu.c
modified: arch/x86/cpu_caps.c
modified: arch/x86/guest/vcpu.c
new file: arch/x86/security.c
modified: arch/x86/trusty.c
modified: arch/x86/vmx_asm.S
modified: include/arch/x86/cpu.h
modified: include/arch/x86/cpu_caps.h
modified: include/arch/x86/per_cpu.h
new file: include/arch/x86/security.h
Tracked-On: #1842
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>