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authorJing Liu <jing2.liu@intel.com>2022-01-05 15:35:22 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2022-01-14 21:44:08 +0300
commit1df4fd834e8e2c00973ac2003ad0e6feb8750b31 (patch)
tree5869df242aa14cd54082dae5af078da34ded2e4a /arch/x86/include/asm/fpu
parent820a6ee944e74e57255ac2e90916ecdaade57b95 (diff)
downloadlinux-1df4fd834e8e2c00973ac2003ad0e6feb8750b31.tar.xz
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/include/asm/fpu')
-rw-r--r--arch/x86/include/asm/fpu/types.h5
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;