mainline inclusion
from mainline-v5.16-rc1
commit b56d2795
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit b56d2795 x86/fpu: Replace the includes of fpu/internal.h.

--------------------------------

Now that the file is empty, fixup all references with the proper includes
and delete the former kitchen sink.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011540.001197214@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 6415bb80
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 6415bb80 x86/fpu: Mop up the internal.h leftovers.

--------------------------------

Move the global interfaces to api.h and the rest into the core.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.948837194@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 0ae67cc3
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 0ae67cc3 x86/fpu: Remove internal.h dependency from fpu/signal.h.

--------------------------------

In order to remove internal.h make signal.h independent of it.

Include asm/fpu/xstate.h to fix a missing update_regset_xstate_info()
prototype, which is
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.844565975@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 90489f1d
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 90489f1d x86/fpu: Move fpstate functions to api.h.

--------------------------------

Move function declarations which need to be globally available to api.h
where they belong.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.792363754@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 9848fb96
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 9848fb96 x86/fpu: Move fpregs_restore_userregs() to core.

--------------------------------

Only used internally in the FPU core code.

While at it, convert to the percpu accessors which verify preemption is
disabled.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.686806639@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit cdcb6fa1
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit cdcb6fa1 x86/fpu: Make WARN_ON_FPU() private.

--------------------------------

No point in being in global headers.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.628516182@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 34002571
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 34002571 x86/fpu: Move legacy ASM wrappers to core.

--------------------------------

Nothing outside the core code requires them.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.572439164@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit df95b0f1
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit df95b0f1 x86/fpu: Move os_xsave() and os_xrstor() to core.

--------------------------------

Nothing outside the core code needs these.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.513368075@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit b579d0c3
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit b579d0c3 x86/fpu: Make os_xrstor_booting() private.

--------------------------------

It's only required in the xstate init code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.455836597@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit d06241f5
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit d06241f5 x86/fpu: Clean up CPU feature tests.

--------------------------------

Further disintegration of internal.h:

Move the CPU feature tests to a core header and remove the unused one.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.401510559@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 63e81807
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 63e81807 x86/fpu: Move context switch and exit to user inlines into sched.h.

--------------------------------

internal.h is a kitchen sink which needs to get out of the way to prepare
for the upcoming changes.

Move the context switch and exit to user inlines into a separate header,
which is all that code needs.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011539.349132461@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit a0ff0611
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit a0ff0611 x86/fpu: Move KVMs FPU swapping to FPU core.

--------------------------------

Swapping the host/guest FPU is directly fiddling with FPU internals which
requires 5 exports. The upcoming support of dynamically enabled states
would even need more.

Implement a swap function in the FPU core code and export that instead.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Link: https://lkml.kernel.org/r/20211015011539.076072399@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 126fe040
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 126fe040 x86/fpu: Cleanup xstate xcomp_bv initialization.

--------------------------------

No point in having this duplicated all over the place with needlessly
different defines.

Provide a proper initialization function which initializes user buffers
properly and make KVM use it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011538.897664678@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 9568bfb4
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 9568bfb4 x86/fpu: Remove pointless argument from switch_fpu_finish().

--------------------------------

Unused since the FPU switching rework.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211015011538.433135710@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit f3305be5
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit f3305be5 x86/fpu/signal: Change return type of fpu__restore_sig() to boolean.

--------------------------------

None of the call sites cares about the error code. All they need to know is
whether the function succeeded or not.
Suggested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210908132525.909065931@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 052adee6
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 052adee6 x86/fpu/signal: Change return type of copy_fpstate_to_sigframe() to boolean.

--------------------------------

None of the call sites cares about the actual return code. Change the
return type to boolean and return 'true' on success.
Suggested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210908132525.736773588@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 4164a482
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 4164a482 x86/fpu/signal: Move header zeroing out of xsave_to_user_sigframe().

--------------------------------

There is no reason to have the header zeroing in the pagefault disabled
region. Do it upfront once.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210908132525.621674721@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 4339d0c6
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 4339d0c6 x86/fpu/signal: Clarify exception handling in restore_fpregs_from_user().

--------------------------------

FPU restore from a signal frame can trigger various exceptions. The
exceptions are caught with an exception table entry. The handler of this
entry stores the trap number in EAX. The FPU specific fixup negates that
trap number to convert it into an negative error code.

Any other exception than #PF is fatal and recovery is not possible. This
relies on the fact that the #PF exception number is the same as EFAULT, but
that's not really obvious.

Remove the negation from the exception fixup as it really has no value and
check for X86_TRAP_PF at the call site.

There is still confusion due to the return code conversion for the error
case which will be cleaned up separately.
Suggested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210908132525.506192488@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit c6304556
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit c6304556 x86/fpu: Use EX_TYPE_FAULT_MCE_SAFE for exception fixups.

--------------------------------

The macros used for restoring FPU state from a user space buffer can handle
all exceptions including #MC. They need to return the trap number in the
error case as the code which invokes them needs to distinguish the cause of
the failure. It aborts the operation for anything except #PF.

Use the new EX_TYPE_FAULT_MCE_SAFE exception table fixup type to document
the nature of the fixup.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210908132525.387464538@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.16-rc1
commit 46d28947
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 46d28947 x86/extable: Rework the exception table mechanics.

--------------------------------

The exception table entries contain the instruction address, the fixup
address and the handler address. All addresses are relative. Storing the
handler address has a few downsides:

 1) Most handlers need to be exported

 2) Handlers can be defined everywhere and there is no overview about the
    handler types

 3) MCE needs to check the handler type to decide whether an in kernel #MC
    can be recovered. The functionality of the handler itself is not in any
    way special, but for these checks there need to be separate functions
    which in the worst case have to be exported.

    Some of these 'recoverable' exception fixups are pretty obscure and
    just reuse some other handler to spare code. That obfuscates e.g. the
    #MC safe copy functions. Cleaning that up would require more handlers
    and exports

Rework the exception fixup mechanics by storing a fixup type number instead
of the handler address and invoke the proper handler for each fixup
type. Also teach the extable sort to leave the type field alone.

This makes most handlers static except for special cases like the MCE
MSR fixup and the BPF fixup. This allows to add more types for cleaning up
the obscure places without adding more handler code and exports.

There is a marginal code size reduction for a production config and it
removes _eight_ exported symbols.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lkml.kernel.org/r/20210908132525.211958725@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 95443698
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 95443698 x86/fpu: Remove PKRU handling from switch_fpu_finish().

--------------------------------

PKRU is already updated and the xstate is not longer the proper source
of information.

 [ bp: Use cpu_feature_enabled() ]
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.708180184@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 30a304a1
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 30a304a1 x86/fpu: Mask PKRU from kernel XRSTOR[S] operations.

--------------------------------

As the PKRU state is managed separately restoring it from the xstate
buffer would be counterproductive as it might either restore a stale
value or reinit the PKRU state to 0.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.606745195@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 2ebe81c6
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 2ebe81c6 x86/fpu: Dont restore PKRU in fpregs_restore_userspace().

--------------------------------

switch_to() and flush_thread() write the task's PKRU value eagerly so
the PKRU value of current is always valid in the hardware.

That means there is no point in restoring PKRU on exit to user or when
reactivating the task's FPU registers in the signal frame setup path.

This allows to remove all the xstate buffer updates with PKRU values once
the PKRU state is stored in thread struct while a task is scheduled out.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.303919033@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 65e95210
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 65e95210 x86/fpu: Rename xfeatures_mask_user() to xfeatures_mask_uabi().

--------------------------------

Rename it so it's clear that this is about user ABI features which can
differ from the feature set which the kernel saves and restores because the
kernel handles e.g. PKRU differently. But the user ABI (ptrace, signal
frame) expects it to be there.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.211585137@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 1d9bffab
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 1d9bffab x86/fpu: Move FXSAVE_LEAK quirk into __copy_kernel_to_fpregs().

--------------------------------

copy_kernel_to_fpregs() restores all xfeatures but it is also the place
where the AMD FXSAVE_LEAK bug is handled.

That prevents fpregs_restore_userregs() to limit the restored features,
which is required to untangle PKRU and XSTATE handling and also for the
upcoming supervisor state management.

Move the FXSAVE_LEAK quirk into __copy_kernel_to_fpregs() and deinline that
function which has become rather fat.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.114271278@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 727d0110
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 727d0110 x86/fpu: Rename __fpregs_load_activate() to fpregs_restore_userregs().

--------------------------------

Rename it so that it becomes entirely clear what this function is
about. It's purpose is to restore the FPU registers to the state which was
saved in the task's FPU memory state either at context switch or by an in
kernel FPU user.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.018867925@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit e7ecad17
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit e7ecad17 x86/fpu: Rename fpu__clear_all() to fpu_flush_thread().

--------------------------------

Make it clear what the function is about.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121455.827979263@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit b2681e79
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit b2681e79 x86/fpu: Rename and sanitize fpu__save/copy().

--------------------------------

Both function names are a misnomer.

fpu__save() is actually about synchronizing the hardware register state
into the task's memory state so that either coredump or a math exception
handler can inspect the state at the time where the problem happens.

The function guarantees to preserve the register state, while "save" is a
common terminology for saving the current state so it can be modified and
restored later. This is clearly not the case here.

Rename it to fpu_sync_fpstate().

fpu__copy() is used to clone the current task's FPU state when duplicating
task_struct. While the register state is a copy the rest of the FPU state
is not.

Name it accordingly and remove the really pointless @src argument along
with the warning which comes along with it.

Nothing can ever copy the FPU state of a non-current task. It's clearly
just a consequence of arch_dup_task_struct(), but it makes no sense to
proliferate that further.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121455.196727450@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 1c61fada
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 1c61fada x86/fpu: Rename copy_kernel_to_fpregs() to restore_fpregs_from_fpstate().

--------------------------------

This is not a copy functionality. It restores the register state from the
supplied kernel buffer.

No functional changes.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.716058365@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 08ded2cd
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 08ded2cd x86/fpu: Get rid of the FNSAVE optimization.

--------------------------------

The FNSAVE support requires conditionals in quite some call paths because
FNSAVE reinitializes the FPU hardware. If the save has to preserve the FPU
register state then the caller has to conditionally restore it from memory
when FNSAVE is in use.

This also requires a conditional in context switch because the restore
avoidance optimization cannot work with FNSAVE. As this only affects 20+
years old CPUs there is really no reason to keep this optimization
effective for FNSAVE. It's about time to not optimize for antiques anymore.

Just unconditionally FRSTOR the save content to the registers and clean up
the conditionals all over the place.
Suggested-by: NDave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.617369268@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit ebe7234b
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit ebe7234b x86/fpu: Rename copy_fpregs_to_fpstate() to save_fpregs_to_fpstate().

--------------------------------

A copy is guaranteed to leave the source intact, which is not the case when
FNSAVE is used as that reinitilizes the registers.

Save does not make such guarantees and it matches what this is about,
i.e. to save the state for a later restore.

Rename it to save_fpregs_to_fpstate().
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.508853062@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 6fdc908c
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 6fdc908c x86/fpu: Rename fregs-related copy functions.

--------------------------------

The function names for fnsave/fnrstor operations are horribly named and
a permanent source of confusion.

Rename:
	copy_kernel_to_fregs() to frstor()
	copy_fregs_to_user()   to fnsave_to_user_sigframe()
	copy_user_to_fregs()   to frstor_from_user_sigframe()

so it's clear what these are doing. All these functions are really low
level wrappers around the equally named instructions, so mapping to the
documentation is just natural.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.223594101@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 16dcf438
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 16dcf438 x86/fpu: Rename fxregs-related copy functions.

--------------------------------

The function names for fxsave/fxrstor operations are horribly named and
a permanent source of confusion.

Rename:
	copy_fxregs_to_kernel() to fxsave()
	copy_kernel_to_fxregs() to fxrstor()
	copy_fxregs_to_user() to fxsave_to_user_sigframe()
	copy_user_to_fxregs() to fxrstor_from_user_sigframe()

so it's clear what these are doing. All these functions are really low
level wrappers around the equally named instructions, so mapping to the
documentation is just natural.

While at it, replace the static_cpu_has(X86_FEATURE_FXSR) with
use_fxsr() to be consistent with the rest of the code.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121454.017863494@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 6b862ba1 x86/fpu: Rename copy_user_to_xregs() and copy_xregs_to_user().

--------------------------------

The function names for xsave[s]/xrstor[s] operations are horribly named and
a permanent source of confusion.

Rename:
	copy_xregs_to_user() to xsave_to_user_sigframe()
	copy_user_to_xregs() to xrstor_from_user_sigframe()

so it's entirely clear what this is about. This is also a clear indicator
of the potentially different storage format because this is user ABI and
cannot use compacted format.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.924266705@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit b16313f7
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit b16313f7 x86/fpu: Rename copy_xregs_to_kernel() and copy_kernel_to_xregs().

--------------------------------

The function names for xsave[s]/xrstor[s] operations are horribly named and
a permanent source of confusion.

Rename:
	copy_xregs_to_kernel() to os_xsave()
	copy_kernel_to_xregs() to os_xrstor()

These are truly low level wrappers around the actual instructions
XSAVE[OPT]/XRSTOR and XSAVES/XRSTORS with the twist that the selection
based on the available CPU features happens with an alternative to avoid
conditionals all over the place and to provide the best performance for hot
paths.

The os_ prefix tells that this is the OS selected mechanism.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.830239347@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit dbb60ac7
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit dbb60ac7 x86/fpu: Move fpu__write_begin() to regset.

--------------------------------

The only usecase for fpu__write_begin is the set() callback of regset, so
the function is pointlessly global.

Move it to the regset code and rename it to fpu_force_restore() which is
exactly decribing what the function does.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.328652975@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit 5a32fac8
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 5a32fac8 x86/fpu/regset: Move fpu__read_begin() into regset.

--------------------------------

The function can only be used from the regset get() callbacks safely. So
there is no reason to have it globally exposed.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.234942936@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit afac9e89
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit afac9e89 x86/fpu: Remove fpstate_sanitize_xstate().

--------------------------------

No more users.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.124819167@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit e6852445
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit e6852445 x86/fpu: Move inlines where they belong.

--------------------------------

They are only used in fpstate_init() and there is no point to have them in
a header just to make reading the code harder.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121452.023118522@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>

mainline inclusion
from mainline-v5.14-rc1
commit ce38f038
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit ce38f038 x86/fpu: Get rid of fpu__get_supported_xfeatures_mask().

--------------------------------

This function is really not doing what the comment advertises:

 "Find supported xfeatures based on cpu features and command-line input.
  This must be called after fpu__init_parse_early_param() is called and
  xfeatures_mask is enumerated."

fpu__init_parse_early_param() does not exist anymore and the function just
returns a constant.

Remove it and fix the caller and get rid of further references to
fpu__init_parse_early_param().
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121451.816404717@linutronix.deSigned-off-by: NLin Wang <lin.x.wang@intel.com>