diff options
| author | Jing Liu | 2022-01-05 04:35:22 -0800 |
|---|---|---|
| committer | Paolo Bonzini | 2022-01-14 13:44:08 -0500 |
| commit | 1df4fd834e8e2c00973ac2003ad0e6feb8750b31 (patch) | |
| tree | 5869df242aa14cd54082dae5af078da34ded2e4a /arch/x86 | |
| parent | 820a6ee944e74e57255ac2e90916ecdaade57b95 (diff) | |
x86/fpu: Prepare xfd_err in struct fpu_guest
When XFD causes an instruction to generate #NM, IA32_XFD_ERR
contains information about which disabled state components are
being accessed. The #NM handler is expected to check this
information and then enable the state components by clearing
IA32_XFD for the faulting task (if having permission).
If the XFD_ERR value generated in guest is consumed/clobbered
by the host before the guest itself doing so, it may lead to
non-XFD-related #NM treated as XFD #NM in host (due to non-zero
value in XFD_ERR), or XFD-related #NM treated as non-XFD #NM in
guest (XFD_ERR cleared by the host #NM handler).
Introduce a new field in fpu_guest to save the guest xfd_err value.
KVM is expected to save guest xfd_err before interrupt is enabled
and restore it right before entering the guest (with interrupt
disabled).
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-12-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/fpu/types.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index c752d0aa23a4..3795d0573773 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -518,6 +518,11 @@ struct fpu_guest { u64 perm; /* + * @xfd_err: Save the guest value. + */ + u64 xfd_err; + + /* * @fpstate: Pointer to the allocated guest fpstate */ struct fpstate *fpstate; |