diff mbox series

[tip:,ras/core] x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()

Message ID 160197822988.7002.13716982099938468868.tip-bot2@tip-bot2
State New
Headers show
Series [tip:,ras/core] x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}() | expand

Commit Message

thermal-bot for Julien Panis Oct. 6, 2020, 9:57 a.m. UTC
The following commit has been merged into the ras/core branch of tip:

Commit-ID:     ec6347bb43395cb92126788a1a5b25302543f815
Gitweb:        https://git.kernel.org/tip/ec6347bb43395cb92126788a1a5b25302543f815
Author:        Dan Williams <dan.j.williams@intel.com>
AuthorDate:    Mon, 05 Oct 2020 20:40:16 -07:00
Committer:     Borislav Petkov <bp@suse.de>
CommitterDate: Tue, 06 Oct 2020 11:18:04 +02:00

x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()

In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.

Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:

  On Fri, May 1, 2020 at 11:28 AM Linus Torvalds <torvalds@linux-foundation.org> wrote:
  >
  > On Thu, Apr 30, 2020 at 6:21 PM Dan Williams <dan.j.williams@intel.com> wrote:
  > >
  > > However now I see that copy_user_generic() works for the wrong reason.
  > > It works because the exception on the source address due to poison
  > > looks no different than a write fault on the user address to the
  > > caller, it's still just a short copy. So it makes copy_to_user() work
  > > for the wrong reason relative to the name.
  >
  > Right.
  >
  > And it won't work that way on other architectures. On x86, we have a
  > generic function that can take faults on either side, and we use it
  > for both cases (and for the "in_user" case too), but that's an
  > artifact of the architecture oddity.
  >
  > In fact, it's probably wrong even on x86 - because it can hide bugs -
  > but writing those things is painful enough that everybody prefers
  > having just one function.

Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().

Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.

One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.

 [ bp: Massage a bit. ]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com
---
 arch/powerpc/Kconfig                                         |   2 +-
 arch/powerpc/include/asm/string.h                            |   2 +-
 arch/powerpc/include/asm/uaccess.h                           |  40 +-
 arch/powerpc/lib/Makefile                                    |   2 +-
 arch/powerpc/lib/copy_mc_64.S                                | 242 +++++++-
 arch/powerpc/lib/memcpy_mcsafe_64.S                          | 242 +-------
 arch/x86/Kconfig                                             |   2 +-
 arch/x86/Kconfig.debug                                       |   2 +-
 arch/x86/include/asm/copy_mc_test.h                          |  75 ++-
 arch/x86/include/asm/mce.h                                   |   9 +-
 arch/x86/include/asm/mcsafe_test.h                           |  75 +--
 arch/x86/include/asm/string_64.h                             |  32 +-
 arch/x86/include/asm/uaccess.h                               |   9 +-
 arch/x86/include/asm/uaccess_64.h                            |  20 +-
 arch/x86/kernel/cpu/mce/core.c                               |   8 +-
 arch/x86/kernel/quirks.c                                     |  10 +-
 arch/x86/lib/Makefile                                        |   1 +-
 arch/x86/lib/copy_mc.c                                       |  82 ++-
 arch/x86/lib/copy_mc_64.S                                    | 127 ++++-
 arch/x86/lib/memcpy_64.S                                     | 115 +---
 arch/x86/lib/usercopy_64.c                                   |  21 +-
 drivers/md/dm-writecache.c                                   |  15 +-
 drivers/nvdimm/claim.c                                       |   2 +-
 drivers/nvdimm/pmem.c                                        |   6 +-
 include/linux/string.h                                       |   9 +-
 include/linux/uaccess.h                                      |  13 +-
 include/linux/uio.h                                          |  10 +-
 lib/Kconfig                                                  |   7 +-
 lib/iov_iter.c                                               |  48 +-
 tools/arch/x86/include/asm/mcsafe_test.h                     |  13 +-
 tools/arch/x86/lib/memcpy_64.S                               | 115 +---
 tools/objtool/check.c                                        |   4 +-
 tools/perf/bench/Build                                       |   1 +-
 tools/perf/bench/mem-memcpy-x86-64-lib.c                     |  24 +-
 tools/testing/nvdimm/test/nfit.c                             |  49 +-
 tools/testing/selftests/powerpc/copyloops/.gitignore         |   2 +-
 tools/testing/selftests/powerpc/copyloops/Makefile           |   6 +-
 tools/testing/selftests/powerpc/copyloops/copy_mc_64.S       |   1 +-
 tools/testing/selftests/powerpc/copyloops/memcpy_mcsafe_64.S |   1 +-
 39 files changed, 673 insertions(+), 771 deletions(-)
 create mode 100644 arch/powerpc/lib/copy_mc_64.S
 delete mode 100644 arch/powerpc/lib/memcpy_mcsafe_64.S
 create mode 100644 arch/x86/include/asm/copy_mc_test.h
 delete mode 100644 arch/x86/include/asm/mcsafe_test.h
 create mode 100644 arch/x86/lib/copy_mc.c
 create mode 100644 arch/x86/lib/copy_mc_64.S
 delete mode 100644 tools/arch/x86/include/asm/mcsafe_test.h
 delete mode 100644 tools/perf/bench/mem-memcpy-x86-64-lib.c
 create mode 120000 tools/testing/selftests/powerpc/copyloops/copy_mc_64.S
 delete mode 120000 tools/testing/selftests/powerpc/copyloops/memcpy_mcsafe_64.S

Comments

Borislav Petkov Oct. 7, 2020, 11:14 a.m. UTC | #1
On Tue, Oct 06, 2020 at 09:57:09AM -0000, tip-bot2 for Dan Williams wrote:
> +	/* Copy successful. Return zero */
> +.L_done_memcpy_trap:
> +	xorl %eax, %eax
> +.L_done:
> +	ret
> +SYM_FUNC_END(copy_mc_fragile)
> +EXPORT_SYMBOL_GPL(copy_mc_fragile)

That export together with CONFIG_MODVERSIONS causes

WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version generation failed, symbol will not be versioned.

here.

I don't see why tho...
Borislav Petkov Oct. 7, 2020, 4:45 p.m. UTC | #2
On Wed, Oct 07, 2020 at 01:14:47PM +0200, Borislav Petkov wrote:
> On Tue, Oct 06, 2020 at 09:57:09AM -0000, tip-bot2 for Dan Williams wrote:
> > +	/* Copy successful. Return zero */
> > +.L_done_memcpy_trap:
> > +	xorl %eax, %eax
> > +.L_done:
> > +	ret
> > +SYM_FUNC_END(copy_mc_fragile)
> > +EXPORT_SYMBOL_GPL(copy_mc_fragile)
> 
> That export together with CONFIG_MODVERSIONS causes
> 
> WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version generation failed, symbol will not be versioned.
> 
> here.
> 
> I don't see why tho...

It doesn't look like it is toolchain-specific and in both cases,
copy_mc_fragile's checksum is 0.

SUSE Leap 15.1:

Name           : binutils                                        
Version        : 2.32-lp151.3.6.1

$ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers
0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL
0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL

debian testing:

Package: binutils
Version: 2.35-2

$ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers 
0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL
0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL
Borislav Petkov Oct. 7, 2020, 5:03 p.m. UTC | #3
On Wed, Oct 07, 2020 at 06:45:36PM +0200, Borislav Petkov wrote:
> It doesn't look like it is toolchain-specific and in both cases,

> copy_mc_fragile's checksum is 0.

> 

> SUSE Leap 15.1:

> 

> Name           : binutils                                        

> Version        : 2.32-lp151.3.6.1

> 

> $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers

> 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL

> 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL

> 

> debian testing:

> 

> Package: binutils

> Version: 2.35-2

> 

> $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers 

> 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL

> 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL


Ok, I think I have it:

---
From: Borislav Petkov <bp@suse.de>

Date: Wed, 7 Oct 2020 18:55:35 +0200
Subject: [PATCH] x86/mce: Allow for copy_mc_fragile symbol checksum to be generated

Add asm/mce.h to asm/asm-prototypes.h so that that asm symbol's checksum
can be generated in order to support CONFIG_MODVERSIONS with it and fix:

  WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version \
	  generation failed, symbol will not be versioned.

For reference see:

  4efca4ed05cb ("kbuild: modversions for EXPORT_SYMBOL() for asm")
  334bb7738764 ("x86/kbuild: enable modversions for symbols exported from asm")

Fixes: ec6347bb4339 ("x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()")
Signed-off-by: Borislav Petkov <bp@suse.de>

---
 arch/x86/include/asm/asm-prototypes.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h
index 5a42f9206138..51e2bf27cc9b 100644
--- a/arch/x86/include/asm/asm-prototypes.h
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -5,6 +5,7 @@
 #include <asm/string.h>
 #include <asm/page.h>
 #include <asm/checksum.h>
+#include <asm/mce.h>
 
 #include <asm-generic/asm-prototypes.h>
 
-- 
2.21.0

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette
Dan Williams Oct. 7, 2020, 5:51 p.m. UTC | #4
[ add kbuild robot so they can add this check to their reports ]

On Wed, Oct 7, 2020 at 9:47 AM Borislav Petkov <bp@alien8.de> wrote:
>

> On Wed, Oct 07, 2020 at 01:14:47PM +0200, Borislav Petkov wrote:

> > On Tue, Oct 06, 2020 at 09:57:09AM -0000, tip-bot2 for Dan Williams wrote:

> > > +   /* Copy successful. Return zero */

> > > +.L_done_memcpy_trap:

> > > +   xorl %eax, %eax

> > > +.L_done:

> > > +   ret

> > > +SYM_FUNC_END(copy_mc_fragile)

> > > +EXPORT_SYMBOL_GPL(copy_mc_fragile)

> >

> > That export together with CONFIG_MODVERSIONS causes

> >

> > WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version generation failed, symbol will not be versioned.

> >

> > here.

> >

> > I don't see why tho...

>

> It doesn't look like it is toolchain-specific and in both cases,

> copy_mc_fragile's checksum is 0.

>

> SUSE Leap 15.1:

>

> Name           : binutils

> Version        : 2.32-lp151.3.6.1

>

> $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers

> 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL

> 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL

>

> debian testing:

>

> Package: binutils

> Version: 2.35-2

>

> $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers

> 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL

> 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL


Yes, I'm seeing this too on Fedora, I'll take a look.
Dan Williams Oct. 7, 2020, 6:53 p.m. UTC | #5
On Wed, Oct 7, 2020 at 11:47 AM Borislav Petkov <bp@alien8.de> wrote:
>
> On Wed, Oct 07, 2020 at 06:45:36PM +0200, Borislav Petkov wrote:
> > It doesn't look like it is toolchain-specific and in both cases,
> > copy_mc_fragile's checksum is 0.
> >
> > SUSE Leap 15.1:
> >
> > Name           : binutils
> > Version        : 2.32-lp151.3.6.1
> >
> > $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers
> > 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL
> > 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL
> >
> > debian testing:
> >
> > Package: binutils
> > Version: 2.35-2
> >
> > $ grep -E "(copy_mc_fragile|copy_user_generic_unrolled)" Module.symvers
> > 0x00000000      copy_mc_fragile vmlinux EXPORT_SYMBOL_GPL
> > 0xecdcabd2      copy_user_generic_unrolled      vmlinux EXPORT_SYMBOL
>
> Ok, I think I have it:
>
> ---
> From: Borislav Petkov <bp@suse.de>
> Date: Wed, 7 Oct 2020 18:55:35 +0200
> Subject: [PATCH] x86/mce: Allow for copy_mc_fragile symbol checksum to be generated
>
> Add asm/mce.h to asm/asm-prototypes.h so that that asm symbol's checksum
> can be generated in order to support CONFIG_MODVERSIONS with it and fix:
>
>   WARNING: modpost: EXPORT symbol "copy_mc_fragile" [vmlinux] version \
>           generation failed, symbol will not be versioned.
>
> For reference see:
>
>   4efca4ed05cb ("kbuild: modversions for EXPORT_SYMBOL() for asm")
>   334bb7738764 ("x86/kbuild: enable modversions for symbols exported from asm")

Oh nice! I just sent a patch [1] to fix this up as well, but mine goes
after minimizing when it is exported, I think perhaps both are needed.

http://lore.kernel.org/r/160209507277.2768223.9933672492157583642.stgit@dwillia2-desk3.amr.corp.intel.com
Borislav Petkov Oct. 7, 2020, 7:25 p.m. UTC | #6
On Wed, Oct 07, 2020 at 11:53:15AM -0700, Dan Williams wrote:
> Oh nice! I just sent a patch [1] to fix this up as well,

Yeah, for some reason it took you a while to see it - wondering if your
mail servers are slow again.

> but mine goes
> after minimizing when it is exported, I think perhaps both are needed.
> 
> http://lore.kernel.org/r/160209507277.2768223.9933672492157583642.stgit@dwillia2-desk3.amr.corp.intel.com

Looks like it. 

Why not rip out COPY_MC_TEST altogether though? Or you wanna do that
after the merge window?

It would be good to not have that export in 5.10 final if it is not
really needed.

Thx.
Dan Williams Oct. 8, 2020, 4:59 p.m. UTC | #7
On Wed, Oct 7, 2020 at 12:54 PM Borislav Petkov <bp@alien8.de> wrote:
>

> On Wed, Oct 07, 2020 at 11:53:15AM -0700, Dan Williams wrote:

> > Oh nice! I just sent a patch [1] to fix this up as well,

>

> Yeah, for some reason it took you a while to see it - wondering if your

> mail servers are slow again.

>

> > but mine goes

> > after minimizing when it is exported, I think perhaps both are needed.

> >

> > http://lore.kernel.org/r/160209507277.2768223.9933672492157583642.stgit@dwillia2-desk3.amr.corp.intel.com

>

> Looks like it.

>

> Why not rip out COPY_MC_TEST altogether though? Or you wanna do that

> after the merge window?

>

> It would be good to not have that export in 5.10 final if it is not

> really needed.


I'll draft a patch to rip it out. If you have a chance to grab it
before the merge window, great, if not I can funnel it through
nvdimm.git since the bulk of it will be touching
tools/testing/nvdimm/.
Borislav Petkov Oct. 8, 2020, 5:08 p.m. UTC | #8
On Thu, Oct 08, 2020 at 09:59:26AM -0700, Dan Williams wrote:
> I'll draft a patch to rip it out. If you have a chance to grab it
> before the merge window, great, if not I can funnel it through
> nvdimm.git since the bulk of it will be touching
> tools/testing/nvdimm/.

Yeah, this is not urgent stuff to queue it now so I'd prefer it if
you funneled it after the merge window. It is enough that it lands in
5.10-final, I'd say, so that the export doesn't see an official release.

Thx.
diff mbox series

Patch

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1f48bbf..76473ed 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -136,7 +136,7 @@  config PPC
 	select ARCH_HAS_STRICT_KERNEL_RWX	if (PPC32 && !HIBERNATION)
 	select ARCH_HAS_TICK_BROADCAST		if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_HAS_UACCESS_FLUSHCACHE
-	select ARCH_HAS_UACCESS_MCSAFE		if PPC64
+	select ARCH_HAS_COPY_MC			if PPC64
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select ARCH_KEEP_MEMBLOCK
diff --git a/arch/powerpc/include/asm/string.h b/arch/powerpc/include/asm/string.h
index 283552c..2aa0e31 100644
--- a/arch/powerpc/include/asm/string.h
+++ b/arch/powerpc/include/asm/string.h
@@ -53,9 +53,7 @@  void *__memmove(void *to, const void *from, __kernel_size_t n);
 #ifndef CONFIG_KASAN
 #define __HAVE_ARCH_MEMSET32
 #define __HAVE_ARCH_MEMSET64
-#define __HAVE_ARCH_MEMCPY_MCSAFE
 
-extern int memcpy_mcsafe(void *dst, const void *src, __kernel_size_t sz);
 extern void *__memset16(uint16_t *, uint16_t v, __kernel_size_t);
 extern void *__memset32(uint32_t *, uint32_t v, __kernel_size_t);
 extern void *__memset64(uint64_t *, uint64_t v, __kernel_size_t);
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 0069990..20a3537 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -435,6 +435,32 @@  do {								\
 extern unsigned long __copy_tofrom_user(void __user *to,
 		const void __user *from, unsigned long size);
 
+#ifdef CONFIG_ARCH_HAS_COPY_MC
+unsigned long __must_check
+copy_mc_generic(void *to, const void *from, unsigned long size);
+
+static inline unsigned long __must_check
+copy_mc_to_kernel(void *to, const void *from, unsigned long size)
+{
+	return copy_mc_generic(to, from, size);
+}
+#define copy_mc_to_kernel copy_mc_to_kernel
+
+static inline unsigned long __must_check
+copy_mc_to_user(void __user *to, const void *from, unsigned long n)
+{
+	if (likely(check_copy_size(from, n, true))) {
+		if (access_ok(to, n)) {
+			allow_write_to_user(to, n);
+			n = copy_mc_generic((void *)to, from, n);
+			prevent_write_to_user(to, n);
+		}
+	}
+
+	return n;
+}
+#endif
+
 #ifdef __powerpc64__
 static inline unsigned long
 raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
@@ -523,20 +549,6 @@  raw_copy_to_user(void __user *to, const void *from, unsigned long n)
 	return ret;
 }
 
-static __always_inline unsigned long __must_check
-copy_to_user_mcsafe(void __user *to, const void *from, unsigned long n)
-{
-	if (likely(check_copy_size(from, n, true))) {
-		if (access_ok(to, n)) {
-			allow_write_to_user(to, n);
-			n = memcpy_mcsafe((void *)to, from, n);
-			prevent_write_to_user(to, n);
-		}
-	}
-
-	return n;
-}
-
 unsigned long __arch_clear_user(void __user *addr, unsigned long size);
 
 static inline unsigned long clear_user(void __user *addr, unsigned long size)
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index d66a645..69a91b5 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -39,7 +39,7 @@  obj-$(CONFIG_PPC_BOOK3S_64) += copyuser_power7.o copypage_power7.o \
 			       memcpy_power7.o
 
 obj64-y	+= copypage_64.o copyuser_64.o mem_64.o hweight_64.o \
-	   memcpy_64.o memcpy_mcsafe_64.o
+	   memcpy_64.o copy_mc_64.o
 
 ifndef CONFIG_PPC_QUEUED_SPINLOCKS
 obj64-$(CONFIG_SMP)	+= locks.o
diff --git a/arch/powerpc/lib/copy_mc_64.S b/arch/powerpc/lib/copy_mc_64.S
new file mode 100644
index 0000000..88d46c4
--- /dev/null
+++ b/arch/powerpc/lib/copy_mc_64.S
@@ -0,0 +1,242 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) IBM Corporation, 2011
+ * Derived from copyuser_power7.s by Anton Blanchard <anton@au.ibm.com>
+ * Author - Balbir Singh <bsingharora@gmail.com>
+ */
+#include <asm/ppc_asm.h>
+#include <asm/errno.h>
+#include <asm/export.h>
+
+	.macro err1
+100:
+	EX_TABLE(100b,.Ldo_err1)
+	.endm
+
+	.macro err2
+200:
+	EX_TABLE(200b,.Ldo_err2)
+	.endm
+
+	.macro err3
+300:	EX_TABLE(300b,.Ldone)
+	.endm
+
+.Ldo_err2:
+	ld	r22,STK_REG(R22)(r1)
+	ld	r21,STK_REG(R21)(r1)
+	ld	r20,STK_REG(R20)(r1)
+	ld	r19,STK_REG(R19)(r1)
+	ld	r18,STK_REG(R18)(r1)
+	ld	r17,STK_REG(R17)(r1)
+	ld	r16,STK_REG(R16)(r1)
+	ld	r15,STK_REG(R15)(r1)
+	ld	r14,STK_REG(R14)(r1)
+	addi	r1,r1,STACKFRAMESIZE
+.Ldo_err1:
+	/* Do a byte by byte copy to get the exact remaining size */
+	mtctr	r7
+46:
+err3;	lbz	r0,0(r4)
+	addi	r4,r4,1
+err3;	stb	r0,0(r3)
+	addi	r3,r3,1
+	bdnz	46b
+	li	r3,0
+	blr
+
+.Ldone:
+	mfctr	r3
+	blr
+
+
+_GLOBAL(copy_mc_generic)
+	mr	r7,r5
+	cmpldi	r5,16
+	blt	.Lshort_copy
+
+.Lcopy:
+	/* Get the source 8B aligned */
+	neg	r6,r4
+	mtocrf	0x01,r6
+	clrldi	r6,r6,(64-3)
+
+	bf	cr7*4+3,1f
+err1;	lbz	r0,0(r4)
+	addi	r4,r4,1
+err1;	stb	r0,0(r3)
+	addi	r3,r3,1
+	subi	r7,r7,1
+
+1:	bf	cr7*4+2,2f
+err1;	lhz	r0,0(r4)
+	addi	r4,r4,2
+err1;	sth	r0,0(r3)
+	addi	r3,r3,2
+	subi	r7,r7,2
+
+2:	bf	cr7*4+1,3f
+err1;	lwz	r0,0(r4)
+	addi	r4,r4,4
+err1;	stw	r0,0(r3)
+	addi	r3,r3,4
+	subi	r7,r7,4
+
+3:	sub	r5,r5,r6
+	cmpldi	r5,128
+
+	mflr	r0
+	stdu	r1,-STACKFRAMESIZE(r1)
+	std	r14,STK_REG(R14)(r1)
+	std	r15,STK_REG(R15)(r1)
+	std	r16,STK_REG(R16)(r1)
+	std	r17,STK_REG(R17)(r1)
+	std	r18,STK_REG(R18)(r1)
+	std	r19,STK_REG(R19)(r1)
+	std	r20,STK_REG(R20)(r1)
+	std	r21,STK_REG(R21)(r1)
+	std	r22,STK_REG(R22)(r1)
+	std	r0,STACKFRAMESIZE+16(r1)
+
+	blt	5f
+	srdi	r6,r5,7
+	mtctr	r6
+
+	/* Now do cacheline (128B) sized loads and stores. */
+	.align	5
+4:
+err2;	ld	r0,0(r4)
+err2;	ld	r6,8(r4)
+err2;	ld	r8,16(r4)
+err2;	ld	r9,24(r4)
+err2;	ld	r10,32(r4)
+err2;	ld	r11,40(r4)
+err2;	ld	r12,48(r4)
+err2;	ld	r14,56(r4)
+err2;	ld	r15,64(r4)
+err2;	ld	r16,72(r4)
+err2;	ld	r17,80(r4)
+err2;	ld	r18,88(r4)
+err2;	ld	r19,96(r4)
+err2;	ld	r20,104(r4)
+err2;	ld	r21,112(r4)
+err2;	ld	r22,120(r4)
+	addi	r4,r4,128
+err2;	std	r0,0(r3)
+err2;	std	r6,8(r3)
+err2;	std	r8,16(r3)
+err2;	std	r9,24(r3)
+err2;	std	r10,32(r3)
+err2;	std	r11,40(r3)
+err2;	std	r12,48(r3)
+err2;	std	r14,56(r3)
+err2;	std	r15,64(r3)
+err2;	std	r16,72(r3)
+err2;	std	r17,80(r3)
+err2;	std	r18,88(r3)
+err2;	std	r19,96(r3)
+err2;	std	r20,104(r3)
+err2;	std	r21,112(r3)
+err2;	std	r22,120(r3)
+	addi	r3,r3,128
+	subi	r7,r7,128
+	bdnz	4b
+
+	clrldi	r5,r5,(64-7)
+
+	/* Up to 127B to go */
+5:	srdi	r6,r5,4
+	mtocrf	0x01,r6
+
+6:	bf	cr7*4+1,7f
+err2;	ld	r0,0(r4)
+err2;	ld	r6,8(r4)
+err2;	ld	r8,16(r4)
+err2;	ld	r9,24(r4)
+err2;	ld	r10,32(r4)
+err2;	ld	r11,40(r4)
+err2;	ld	r12,48(r4)
+err2;	ld	r14,56(r4)
+	addi	r4,r4,64
+err2;	std	r0,0(r3)
+err2;	std	r6,8(r3)
+err2;	std	r8,16(r3)
+err2;	std	r9,24(r3)
+err2;	std	r10,32(r3)
+err2;	std	r11,40(r3)
+err2;	std	r12,48(r3)
+err2;	std	r14,56(r3)
+	addi	r3,r3,64
+	subi	r7,r7,64
+
+7:	ld	r14,STK_REG(R14)(r1)
+	ld	r15,STK_REG(R15)(r1)
+	ld	r16,STK_REG(R16)(r1)
+	ld	r17,STK_REG(R17)(r1)
+	ld	r18,STK_REG(R18)(r1)
+	ld	r19,STK_REG(R19)(r1)
+	ld	r20,STK_REG(R20)(r1)
+	ld	r21,STK_REG(R21)(r1)
+	ld	r22,STK_REG(R22)(r1)
+	addi	r1,r1,STACKFRAMESIZE
+
+	/* Up to 63B to go */
+	bf	cr7*4+2,8f
+err1;	ld	r0,0(r4)
+err1;	ld	r6,8(r4)
+err1;	ld	r8,16(r4)
+err1;	ld	r9,24(r4)
+	addi	r4,r4,32
+err1;	std	r0,0(r3)
+err1;	std	r6,8(r3)
+err1;	std	r8,16(r3)
+err1;	std	r9,24(r3)
+	addi	r3,r3,32
+	subi	r7,r7,32
+
+	/* Up to 31B to go */
+8:	bf	cr7*4+3,9f
+err1;	ld	r0,0(r4)
+err1;	ld	r6,8(r4)
+	addi	r4,r4,16
+err1;	std	r0,0(r3)
+err1;	std	r6,8(r3)
+	addi	r3,r3,16
+	subi	r7,r7,16
+
+9:	clrldi	r5,r5,(64-4)
+
+	/* Up to 15B to go */
+.Lshort_copy:
+	mtocrf	0x01,r5
+	bf	cr7*4+0,12f
+err1;	lwz	r0,0(r4)	/* Less chance of a reject with word ops */
+err1;	lwz	r6,4(r4)
+	addi	r4,r4,8
+err1;	stw	r0,0(r3)
+err1;	stw	r6,4(r3)
+	addi	r3,r3,8
+	subi	r7,r7,8
+
+12:	bf	cr7*4+1,13f
+err1;	lwz	r0,0(r4)
+	addi	r4,r4,4
+err1;	stw	r0,0(r3)
+	addi	r3,r3,4
+	subi	r7,r7,4
+
+13:	bf	cr7*4+2,14f
+err1;	lhz	r0,0(r4)
+	addi	r4,r4,2
+err1;	sth	r0,0(r3)
+	addi	r3,r3,2
+	subi	r7,r7,2
+
+14:	bf	cr7*4+3,15f
+err1;	lbz	r0,0(r4)
+err1;	stb	r0,0(r3)
+
+15:	li	r3,0
+	blr
+
+EXPORT_SYMBOL_GPL(copy_mc_generic);
diff --git a/arch/powerpc/lib/memcpy_mcsafe_64.S b/arch/powerpc/lib/memcpy_mcsafe_64.S
deleted file mode 100644
index cb882d9..0000000
--- a/arch/powerpc/lib/memcpy_mcsafe_64.S
+++ /dev/null
@@ -1,242 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) IBM Corporation, 2011
- * Derived from copyuser_power7.s by Anton Blanchard <anton@au.ibm.com>
- * Author - Balbir Singh <bsingharora@gmail.com>
- */
-#include <asm/ppc_asm.h>
-#include <asm/errno.h>
-#include <asm/export.h>
-
-	.macro err1
-100:
-	EX_TABLE(100b,.Ldo_err1)
-	.endm
-
-	.macro err2
-200:
-	EX_TABLE(200b,.Ldo_err2)
-	.endm
-
-	.macro err3
-300:	EX_TABLE(300b,.Ldone)
-	.endm
-
-.Ldo_err2:
-	ld	r22,STK_REG(R22)(r1)
-	ld	r21,STK_REG(R21)(r1)
-	ld	r20,STK_REG(R20)(r1)
-	ld	r19,STK_REG(R19)(r1)
-	ld	r18,STK_REG(R18)(r1)
-	ld	r17,STK_REG(R17)(r1)
-	ld	r16,STK_REG(R16)(r1)
-	ld	r15,STK_REG(R15)(r1)
-	ld	r14,STK_REG(R14)(r1)
-	addi	r1,r1,STACKFRAMESIZE
-.Ldo_err1:
-	/* Do a byte by byte copy to get the exact remaining size */
-	mtctr	r7
-46:
-err3;	lbz	r0,0(r4)
-	addi	r4,r4,1
-err3;	stb	r0,0(r3)
-	addi	r3,r3,1
-	bdnz	46b
-	li	r3,0
-	blr
-
-.Ldone:
-	mfctr	r3
-	blr
-
-
-_GLOBAL(memcpy_mcsafe)
-	mr	r7,r5
-	cmpldi	r5,16
-	blt	.Lshort_copy
-
-.Lcopy:
-	/* Get the source 8B aligned */
-	neg	r6,r4
-	mtocrf	0x01,r6
-	clrldi	r6,r6,(64-3)
-
-	bf	cr7*4+3,1f
-err1;	lbz	r0,0(r4)
-	addi	r4,r4,1
-err1;	stb	r0,0(r3)
-	addi	r3,r3,1
-	subi	r7,r7,1
-
-1:	bf	cr7*4+2,2f
-err1;	lhz	r0,0(r4)
-	addi	r4,r4,2
-err1;	sth	r0,0(r3)
-	addi	r3,r3,2
-	subi	r7,r7,2
-
-2:	bf	cr7*4+1,3f
-err1;	lwz	r0,0(r4)
-	addi	r4,r4,4
-err1;	stw	r0,0(r3)
-	addi	r3,r3,4
-	subi	r7,r7,4
-
-3:	sub	r5,r5,r6
-	cmpldi	r5,128
-
-	mflr	r0
-	stdu	r1,-STACKFRAMESIZE(r1)
-	std	r14,STK_REG(R14)(r1)
-	std	r15,STK_REG(R15)(r1)
-	std	r16,STK_REG(R16)(r1)
-	std	r17,STK_REG(R17)(r1)
-	std	r18,STK_REG(R18)(r1)
-	std	r19,STK_REG(R19)(r1)
-	std	r20,STK_REG(R20)(r1)
-	std	r21,STK_REG(R21)(r1)
-	std	r22,STK_REG(R22)(r1)
-	std	r0,STACKFRAMESIZE+16(r1)
-
-	blt	5f
-	srdi	r6,r5,7
-	mtctr	r6
-
-	/* Now do cacheline (128B) sized loads and stores. */
-	.align	5
-4:
-err2;	ld	r0,0(r4)
-err2;	ld	r6,8(r4)
-err2;	ld	r8,16(r4)
-err2;	ld	r9,24(r4)
-err2;	ld	r10,32(r4)
-err2;	ld	r11,40(r4)
-err2;	ld	r12,48(r4)
-err2;	ld	r14,56(r4)
-err2;	ld	r15,64(r4)
-err2;	ld	r16,72(r4)
-err2;	ld	r17,80(r4)
-err2;	ld	r18,88(r4)
-err2;	ld	r19,96(r4)
-err2;	ld	r20,104(r4)
-err2;	ld	r21,112(r4)
-err2;	ld	r22,120(r4)
-	addi	r4,r4,128
-err2;	std	r0,0(r3)
-err2;	std	r6,8(r3)
-err2;	std	r8,16(r3)
-err2;	std	r9,24(r3)
-err2;	std	r10,32(r3)
-err2;	std	r11,40(r3)
-err2;	std	r12,48(r3)
-err2;	std	r14,56(r3)
-err2;	std	r15,64(r3)
-err2;	std	r16,72(r3)
-err2;	std	r17,80(r3)
-err2;	std	r18,88(r3)
-err2;	std	r19,96(r3)
-err2;	std	r20,104(r3)
-err2;	std	r21,112(r3)
-err2;	std	r22,120(r3)
-	addi	r3,r3,128
-	subi	r7,r7,128
-	bdnz	4b
-
-	clrldi	r5,r5,(64-7)
-
-	/* Up to 127B to go */
-5:	srdi	r6,r5,4
-	mtocrf	0x01,r6
-
-6:	bf	cr7*4+1,7f
-err2;	ld	r0,0(r4)
-err2;	ld	r6,8(r4)
-err2;	ld	r8,16(r4)
-err2;	ld	r9,24(r4)
-err2;	ld	r10,32(r4)
-err2;	ld	r11,40(r4)
-err2;	ld	r12,48(r4)
-err2;	ld	r14,56(r4)
-	addi	r4,r4,64
-err2;	std	r0,0(r3)
-err2;	std	r6,8(r3)
-err2;	std	r8,16(r3)
-err2;	std	r9,24(r3)
-err2;	std	r10,32(r3)
-err2;	std	r11,40(r3)
-err2;	std	r12,48(r3)
-err2;	std	r14,56(r3)
-	addi	r3,r3,64
-	subi	r7,r7,64
-
-7:	ld	r14,STK_REG(R14)(r1)
-	ld	r15,STK_REG(R15)(r1)
-	ld	r16,STK_REG(R16)(r1)
-	ld	r17,STK_REG(R17)(r1)
-	ld	r18,STK_REG(R18)(r1)
-	ld	r19,STK_REG(R19)(r1)
-	ld	r20,STK_REG(R20)(r1)
-	ld	r21,STK_REG(R21)(r1)
-	ld	r22,STK_REG(R22)(r1)
-	addi	r1,r1,STACKFRAMESIZE
-
-	/* Up to 63B to go */
-	bf	cr7*4+2,8f
-err1;	ld	r0,0(r4)
-err1;	ld	r6,8(r4)
-err1;	ld	r8,16(r4)
-err1;	ld	r9,24(r4)
-	addi	r4,r4,32
-err1;	std	r0,0(r3)
-err1;	std	r6,8(r3)
-err1;	std	r8,16(r3)
-err1;	std	r9,24(r3)
-	addi	r3,r3,32
-	subi	r7,r7,32
-
-	/* Up to 31B to go */
-8:	bf	cr7*4+3,9f
-err1;	ld	r0,0(r4)
-err1;	ld	r6,8(r4)
-	addi	r4,r4,16
-err1;	std	r0,0(r3)
-err1;	std	r6,8(r3)
-	addi	r3,r3,16
-	subi	r7,r7,16
-
-9:	clrldi	r5,r5,(64-4)
-
-	/* Up to 15B to go */
-.Lshort_copy:
-	mtocrf	0x01,r5
-	bf	cr7*4+0,12f
-err1;	lwz	r0,0(r4)	/* Less chance of a reject with word ops */
-err1;	lwz	r6,4(r4)
-	addi	r4,r4,8
-err1;	stw	r0,0(r3)
-err1;	stw	r6,4(r3)
-	addi	r3,r3,8
-	subi	r7,r7,8
-
-12:	bf	cr7*4+1,13f
-err1;	lwz	r0,0(r4)
-	addi	r4,r4,4
-err1;	stw	r0,0(r3)
-	addi	r3,r3,4
-	subi	r7,r7,4
-
-13:	bf	cr7*4+2,14f
-err1;	lhz	r0,0(r4)
-	addi	r4,r4,2
-err1;	sth	r0,0(r3)
-	addi	r3,r3,2
-	subi	r7,r7,2
-
-14:	bf	cr7*4+3,15f
-err1;	lbz	r0,0(r4)
-err1;	stb	r0,0(r3)
-
-15:	li	r3,0
-	blr
-
-EXPORT_SYMBOL_GPL(memcpy_mcsafe);
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7101ac6..e876b3a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -75,7 +75,7 @@  config X86
 	select ARCH_HAS_PTE_DEVMAP		if X86_64
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
-	select ARCH_HAS_UACCESS_MCSAFE		if X86_64 && X86_MCE
+	select ARCH_HAS_COPY_MC			if X86_64
 	select ARCH_HAS_SET_MEMORY
 	select ARCH_HAS_SET_DIRECT_MAP
 	select ARCH_HAS_STRICT_KERNEL_RWX
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index ee1d3c5..27b5e2b 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -62,7 +62,7 @@  config EARLY_PRINTK_USB_XDBC
 	  You should normally say N here, unless you want to debug early
 	  crashes or need a very simple printk logging facility.
 
-config MCSAFE_TEST
+config COPY_MC_TEST
 	def_bool n
 
 config EFI_PGT_DUMP
diff --git a/arch/x86/include/asm/copy_mc_test.h b/arch/x86/include/asm/copy_mc_test.h
new file mode 100644
index 0000000..e4991ba
--- /dev/null
+++ b/arch/x86/include/asm/copy_mc_test.h
@@ -0,0 +1,75 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _COPY_MC_TEST_H_
+#define _COPY_MC_TEST_H_
+
+#ifndef __ASSEMBLY__
+#ifdef CONFIG_COPY_MC_TEST
+extern unsigned long copy_mc_test_src;
+extern unsigned long copy_mc_test_dst;
+
+static inline void copy_mc_inject_src(void *addr)
+{
+	if (addr)
+		copy_mc_test_src = (unsigned long) addr;
+	else
+		copy_mc_test_src = ~0UL;
+}
+
+static inline void copy_mc_inject_dst(void *addr)
+{
+	if (addr)
+		copy_mc_test_dst = (unsigned long) addr;
+	else
+		copy_mc_test_dst = ~0UL;
+}
+#else /* CONFIG_COPY_MC_TEST */
+static inline void copy_mc_inject_src(void *addr)
+{
+}
+
+static inline void copy_mc_inject_dst(void *addr)
+{
+}
+#endif /* CONFIG_COPY_MC_TEST */
+
+#else /* __ASSEMBLY__ */
+#include <asm/export.h>
+
+#ifdef CONFIG_COPY_MC_TEST
+.macro COPY_MC_TEST_CTL
+	.pushsection .data
+	.align 8
+	.globl copy_mc_test_src
+	copy_mc_test_src:
+		.quad 0
+	EXPORT_SYMBOL_GPL(copy_mc_test_src)
+	.globl copy_mc_test_dst
+	copy_mc_test_dst:
+		.quad 0
+	EXPORT_SYMBOL_GPL(copy_mc_test_dst)
+	.popsection
+.endm
+
+.macro COPY_MC_TEST_SRC reg count target
+	leaq \count(\reg), %r9
+	cmp copy_mc_test_src, %r9
+	ja \target
+.endm
+
+.macro COPY_MC_TEST_DST reg count target
+	leaq \count(\reg), %r9
+	cmp copy_mc_test_dst, %r9
+	ja \target
+.endm
+#else
+.macro COPY_MC_TEST_CTL
+.endm
+
+.macro COPY_MC_TEST_SRC reg count target
+.endm
+
+.macro COPY_MC_TEST_DST reg count target
+.endm
+#endif /* CONFIG_COPY_MC_TEST */
+#endif /* __ASSEMBLY__ */
+#endif /* _COPY_MC_TEST_H_ */
diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 109af5c..ba2062d 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -174,6 +174,15 @@  extern void mce_unregister_decode_chain(struct notifier_block *nb);
 
 extern int mce_p5_enabled;
 
+#ifdef CONFIG_ARCH_HAS_COPY_MC
+extern void enable_copy_mc_fragile(void);
+unsigned long __must_check copy_mc_fragile(void *dst, const void *src, unsigned cnt);
+#else
+static inline void enable_copy_mc_fragile(void)
+{
+}
+#endif
+
 #ifdef CONFIG_X86_MCE
 int mcheck_init(void);
 void mcheck_cpu_init(struct cpuinfo_x86 *c);
diff --git a/arch/x86/include/asm/mcsafe_test.h b/arch/x86/include/asm/mcsafe_test.h
deleted file mode 100644
index eb59804..0000000
--- a/arch/x86/include/asm/mcsafe_test.h
+++ /dev/null
@@ -1,75 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _MCSAFE_TEST_H_
-#define _MCSAFE_TEST_H_
-
-#ifndef __ASSEMBLY__
-#ifdef CONFIG_MCSAFE_TEST
-extern unsigned long mcsafe_test_src;
-extern unsigned long mcsafe_test_dst;
-
-static inline void mcsafe_inject_src(void *addr)
-{
-	if (addr)
-		mcsafe_test_src = (unsigned long) addr;
-	else
-		mcsafe_test_src = ~0UL;
-}
-
-static inline void mcsafe_inject_dst(void *addr)
-{
-	if (addr)
-		mcsafe_test_dst = (unsigned long) addr;
-	else
-		mcsafe_test_dst = ~0UL;
-}
-#else /* CONFIG_MCSAFE_TEST */
-static inline void mcsafe_inject_src(void *addr)
-{
-}
-
-static inline void mcsafe_inject_dst(void *addr)
-{
-}
-#endif /* CONFIG_MCSAFE_TEST */
-
-#else /* __ASSEMBLY__ */
-#include <asm/export.h>
-
-#ifdef CONFIG_MCSAFE_TEST
-.macro MCSAFE_TEST_CTL
-	.pushsection .data
-	.align 8
-	.globl mcsafe_test_src
-	mcsafe_test_src:
-		.quad 0
-	EXPORT_SYMBOL_GPL(mcsafe_test_src)
-	.globl mcsafe_test_dst
-	mcsafe_test_dst:
-		.quad 0
-	EXPORT_SYMBOL_GPL(mcsafe_test_dst)
-	.popsection
-.endm
-
-.macro MCSAFE_TEST_SRC reg count target
-	leaq \count(\reg), %r9
-	cmp mcsafe_test_src, %r9
-	ja \target
-.endm
-
-.macro MCSAFE_TEST_DST reg count target
-	leaq \count(\reg), %r9
-	cmp mcsafe_test_dst, %r9
-	ja \target
-.endm
-#else
-.macro MCSAFE_TEST_CTL
-.endm
-
-.macro MCSAFE_TEST_SRC reg count target
-.endm
-
-.macro MCSAFE_TEST_DST reg count target
-.endm
-#endif /* CONFIG_MCSAFE_TEST */
-#endif /* __ASSEMBLY__ */
-#endif /* _MCSAFE_TEST_H_ */
diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h
index 75314c3..6e45082 100644
--- a/arch/x86/include/asm/string_64.h
+++ b/arch/x86/include/asm/string_64.h
@@ -82,38 +82,6 @@  int strcmp(const char *cs, const char *ct);
 
 #endif
 
-#define __HAVE_ARCH_MEMCPY_MCSAFE 1
-__must_check unsigned long __memcpy_mcsafe(void *dst, const void *src,
-		size_t cnt);
-DECLARE_STATIC_KEY_FALSE(mcsafe_key);
-
-/**
- * memcpy_mcsafe - copy memory with indication if a machine check happened
- *
- * @dst:	destination address
- * @src:	source address
- * @cnt:	number of bytes to copy
- *
- * Low level memory copy function that catches machine checks
- * We only call into the "safe" function on systems that can
- * actually do machine check recovery. Everyone else can just
- * use memcpy().
- *
- * Return 0 for success, or number of bytes not copied if there was an
- * exception.
- */
-static __always_inline __must_check unsigned long
-memcpy_mcsafe(void *dst, const void *src, size_t cnt)
-{
-#ifdef CONFIG_X86_MCE
-	if (static_branch_unlikely(&mcsafe_key))
-		return __memcpy_mcsafe(dst, src, cnt);
-	else
-#endif
-		memcpy(dst, src, cnt);
-	return 0;
-}
-
 #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
 #define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
 void __memcpy_flushcache(void *dst, const void *src, size_t cnt);
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index ecefaff..eff7fb8 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -455,6 +455,15 @@  extern __must_check long strnlen_user(const char __user *str, long n);
 unsigned long __must_check clear_user(void __user *mem, unsigned long len);
 unsigned long __must_check __clear_user(void __user *mem, unsigned long len);
 
+#ifdef CONFIG_ARCH_HAS_COPY_MC
+unsigned long __must_check
+copy_mc_to_kernel(void *to, const void *from, unsigned len);
+#define copy_mc_to_kernel copy_mc_to_kernel
+
+unsigned long __must_check
+copy_mc_to_user(void *to, const void *from, unsigned len);
+#endif
+
 /*
  * movsl can be slow when source and dest are not both 8-byte aligned
  */
diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h
index bc10e3d..e7265a5 100644
--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -47,22 +47,6 @@  copy_user_generic(void *to, const void *from, unsigned len)
 }
 
 static __always_inline __must_check unsigned long
-copy_to_user_mcsafe(void *to, const void *from, unsigned len)
-{
-	unsigned long ret;
-
-	__uaccess_begin();
-	/*
-	 * Note, __memcpy_mcsafe() is explicitly used since it can
-	 * handle exceptions / faults.  memcpy_mcsafe() may fall back to
-	 * memcpy() which lacks this handling.
-	 */
-	ret = __memcpy_mcsafe(to, from, len);
-	__uaccess_end();
-	return ret;
-}
-
-static __always_inline __must_check unsigned long
 raw_copy_from_user(void *dst, const void __user *src, unsigned long size)
 {
 	return copy_user_generic(dst, (__force void *)src, size);
@@ -102,8 +86,4 @@  __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size)
 	kasan_check_write(dst, size);
 	return __copy_user_flushcache(dst, src, size);
 }
-
-unsigned long
-mcsafe_handle_tail(char *to, char *from, unsigned len);
-
 #endif /* _ASM_X86_UACCESS_64_H */
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 11b6697..b5b70f4 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -40,7 +40,6 @@ 
 #include <linux/debugfs.h>
 #include <linux/irq_work.h>
 #include <linux/export.h>
-#include <linux/jump_label.h>
 #include <linux/set_memory.h>
 #include <linux/sync_core.h>
 #include <linux/task_work.h>
@@ -2124,7 +2123,7 @@  void mce_disable_bank(int bank)
 	and older.
  * mce=nobootlog Don't log MCEs from before booting.
  * mce=bios_cmci_threshold Don't program the CMCI threshold
- * mce=recovery force enable memcpy_mcsafe()
+ * mce=recovery force enable copy_mc_fragile()
  */
 static int __init mcheck_enable(char *str)
 {
@@ -2732,13 +2731,10 @@  static void __init mcheck_debugfs_init(void)
 static void __init mcheck_debugfs_init(void) { }
 #endif
 
-DEFINE_STATIC_KEY_FALSE(mcsafe_key);
-EXPORT_SYMBOL_GPL(mcsafe_key);
-
 static int __init mcheck_late_init(void)
 {
 	if (mca_cfg.recovery)
-		static_branch_inc(&mcsafe_key);
+		enable_copy_mc_fragile();
 
 	mcheck_debugfs_init();
 
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c
index 1b10717..6d0df6a 100644
--- a/arch/x86/kernel/quirks.c
+++ b/arch/x86/kernel/quirks.c
@@ -8,6 +8,7 @@ 
 
 #include <asm/hpet.h>
 #include <asm/setup.h>
+#include <asm/mce.h>
 
 #if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_SMP) && defined(CONFIG_PCI)
 
@@ -624,10 +625,6 @@  static void amd_disable_seq_and_redirect_scrub(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3,
 			amd_disable_seq_and_redirect_scrub);
 
-#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE)
-#include <linux/jump_label.h>
-#include <asm/string_64.h>
-
 /* Ivy Bridge, Haswell, Broadwell */
 static void quirk_intel_brickland_xeon_ras_cap(struct pci_dev *pdev)
 {
@@ -636,7 +633,7 @@  static void quirk_intel_brickland_xeon_ras_cap(struct pci_dev *pdev)
 	pci_read_config_dword(pdev, 0x84, &capid0);
 
 	if (capid0 & 0x10)
-		static_branch_inc(&mcsafe_key);
+		enable_copy_mc_fragile();
 }
 
 /* Skylake */
@@ -653,7 +650,7 @@  static void quirk_intel_purley_xeon_ras_cap(struct pci_dev *pdev)
 	 * enabled, so memory machine check recovery is also enabled.
 	 */
 	if ((capid0 & 0xc0) == 0xc0 || (capid5 & 0x1e0))
-		static_branch_inc(&mcsafe_key);
+		enable_copy_mc_fragile();
 
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x0ec3, quirk_intel_brickland_xeon_ras_cap);
@@ -661,7 +658,6 @@  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, quirk_intel_brickland_xeon_
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, quirk_intel_brickland_xeon_ras_cap);
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2083, quirk_intel_purley_xeon_ras_cap);
 #endif
-#endif
 
 bool x86_apple_machine;
 EXPORT_SYMBOL(x86_apple_machine);
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index d46fff1..f7d23c9 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -44,6 +44,7 @@  obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o
 lib-y := delay.o misc.o cmdline.o cpu.o
 lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o
 lib-y += memcpy_$(BITS).o
+lib-$(CONFIG_ARCH_HAS_COPY_MC) += copy_mc.o copy_mc_64.o
 lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o insn-eval.o
 lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
 lib-$(CONFIG_FUNCTION_ERROR_INJECTION)	+= error-inject.o
diff --git a/arch/x86/lib/copy_mc.c b/arch/x86/lib/copy_mc.c
new file mode 100644
index 0000000..2633635
--- /dev/null
+++ b/arch/x86/lib/copy_mc.c
@@ -0,0 +1,82 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016-2020 Intel Corporation. All rights reserved. */
+
+#include <linux/jump_label.h>
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <asm/mce.h>
+
+#ifdef CONFIG_X86_MCE
+/*
+ * See COPY_MC_TEST for self-test of the copy_mc_fragile()
+ * implementation.
+ */
+static DEFINE_STATIC_KEY_FALSE(copy_mc_fragile_key);
+
+void enable_copy_mc_fragile(void)
+{
+	static_branch_inc(&copy_mc_fragile_key);
+}
+#define copy_mc_fragile_enabled (static_branch_unlikely(&copy_mc_fragile_key))
+
+/*
+ * Similar to copy_user_handle_tail, probe for the write fault point, or
+ * source exception point.
+ */
+__visible notrace unsigned long
+copy_mc_fragile_handle_tail(char *to, char *from, unsigned len)
+{
+	for (; len; --len, to++, from++)
+		if (copy_mc_fragile(to, from, 1))
+			break;
+	return len;
+}
+#else
+/*
+ * No point in doing careful copying, or consulting a static key when
+ * there is no #MC handler in the CONFIG_X86_MCE=n case.
+ */
+void enable_copy_mc_fragile(void)
+{
+}
+#define copy_mc_fragile_enabled (0)
+#endif
+
+/**
+ * copy_mc_to_kernel - memory copy that handles source exceptions
+ *
+ * @dst:	destination address
+ * @src:	source address
+ * @len:	number of bytes to copy
+ *
+ * Call into the 'fragile' version on systems that have trouble
+ * actually do machine check recovery. Everyone else can just
+ * use memcpy().
+ *
+ * Return 0 for success, or number of bytes not copied if there was an
+ * exception.
+ */
+unsigned long __must_check copy_mc_to_kernel(void *dst, const void *src, unsigned len)
+{
+	if (copy_mc_fragile_enabled)
+		return copy_mc_fragile(dst, src, len);
+	memcpy(dst, src, len);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(copy_mc_to_kernel);
+
+unsigned long __must_check copy_mc_to_user(void *dst, const void *src, unsigned len)
+{
+	unsigned long ret;
+
+	if (!copy_mc_fragile_enabled)
+		return copy_user_generic(dst, src, len);
+
+	__uaccess_begin();
+	ret = copy_mc_fragile(dst, src, len);
+	__uaccess_end();
+	return ret;
+}
diff --git a/arch/x86/lib/copy_mc_64.S b/arch/x86/lib/copy_mc_64.S
new file mode 100644
index 0000000..c3b613c
--- /dev/null
+++ b/arch/x86/lib/copy_mc_64.S
@@ -0,0 +1,127 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright(c) 2016-2020 Intel Corporation. All rights reserved. */
+
+#include <linux/linkage.h>
+#include <asm/copy_mc_test.h>
+#include <asm/export.h>
+#include <asm/asm.h>
+
+#ifndef CONFIG_UML
+
+#ifdef CONFIG_X86_MCE
+COPY_MC_TEST_CTL
+
+/*
+ * copy_mc_fragile - copy memory with indication if an exception / fault happened
+ *
+ * The 'fragile' version is opted into by platform quirks and takes
+ * pains to avoid unrecoverable corner cases like 'fast-string'
+ * instruction sequences, and consuming poison across a cacheline
+ * boundary. The non-fragile version is equivalent to memcpy()
+ * regardless of CPU machine-check-recovery capability.
+ */
+SYM_FUNC_START(copy_mc_fragile)
+	cmpl $8, %edx
+	/* Less than 8 bytes? Go to byte copy loop */
+	jb .L_no_whole_words
+
+	/* Check for bad alignment of source */
+	testl $7, %esi
+	/* Already aligned */
+	jz .L_8byte_aligned
+
+	/* Copy one byte at a time until source is 8-byte aligned */
+	movl %esi, %ecx
+	andl $7, %ecx
+	subl $8, %ecx
+	negl %ecx
+	subl %ecx, %edx
+.L_read_leading_bytes:
+	movb (%rsi), %al
+	COPY_MC_TEST_SRC %rsi 1 .E_leading_bytes
+	COPY_MC_TEST_DST %rdi 1 .E_leading_bytes
+.L_write_leading_bytes:
+	movb %al, (%rdi)
+	incq %rsi
+	incq %rdi
+	decl %ecx
+	jnz .L_read_leading_bytes
+
+.L_8byte_aligned:
+	movl %edx, %ecx
+	andl $7, %edx
+	shrl $3, %ecx
+	jz .L_no_whole_words
+
+.L_read_words:
+	movq (%rsi), %r8
+	COPY_MC_TEST_SRC %rsi 8 .E_read_words
+	COPY_MC_TEST_DST %rdi 8 .E_write_words
+.L_write_words:
+	movq %r8, (%rdi)
+	addq $8, %rsi
+	addq $8, %rdi
+	decl %ecx
+	jnz .L_read_words
+
+	/* Any trailing bytes? */
+.L_no_whole_words:
+	andl %edx, %edx
+	jz .L_done_memcpy_trap
+
+	/* Copy trailing bytes */
+	movl %edx, %ecx
+.L_read_trailing_bytes:
+	movb (%rsi), %al
+	COPY_MC_TEST_SRC %rsi 1 .E_trailing_bytes
+	COPY_MC_TEST_DST %rdi 1 .E_trailing_bytes
+.L_write_trailing_bytes:
+	movb %al, (%rdi)
+	incq %rsi
+	incq %rdi
+	decl %ecx
+	jnz .L_read_trailing_bytes
+
+	/* Copy successful. Return zero */
+.L_done_memcpy_trap:
+	xorl %eax, %eax
+.L_done:
+	ret
+SYM_FUNC_END(copy_mc_fragile)
+EXPORT_SYMBOL_GPL(copy_mc_fragile)
+
+	.section .fixup, "ax"
+	/*
+	 * Return number of bytes not copied for any failure. Note that
+	 * there is no "tail" handling since the source buffer is 8-byte
+	 * aligned and poison is cacheline aligned.
+	 */
+.E_read_words:
+	shll	$3, %ecx
+.E_leading_bytes:
+	addl	%edx, %ecx
+.E_trailing_bytes:
+	mov	%ecx, %eax
+	jmp	.L_done
+
+	/*
+	 * For write fault handling, given the destination is unaligned,
+	 * we handle faults on multi-byte writes with a byte-by-byte
+	 * copy up to the write-protected page.
+	 */
+.E_write_words:
+	shll	$3, %ecx
+	addl	%edx, %ecx
+	movl	%ecx, %edx
+	jmp copy_mc_fragile_handle_tail
+
+	.previous
+
+	_ASM_EXTABLE_FAULT(.L_read_leading_bytes, .E_leading_bytes)
+	_ASM_EXTABLE_FAULT(.L_read_words, .E_read_words)
+	_ASM_EXTABLE_FAULT(.L_read_trailing_bytes, .E_trailing_bytes)
+	_ASM_EXTABLE(.L_write_leading_bytes, .E_leading_bytes)
+	_ASM_EXTABLE(.L_write_words, .E_write_words)
+	_ASM_EXTABLE(.L_write_trailing_bytes, .E_trailing_bytes)
+#endif /* CONFIG_X86_MCE */
+#endif /* !CONFIG_UML */
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S
index bbcc05b..037faac 100644
--- a/arch/x86/lib/memcpy_64.S
+++ b/arch/x86/lib/memcpy_64.S
@@ -4,7 +4,6 @@ 
 #include <linux/linkage.h>
 #include <asm/errno.h>
 #include <asm/cpufeatures.h>
-#include <asm/mcsafe_test.h>
 #include <asm/alternative-asm.h>
 #include <asm/export.h>
 
@@ -187,117 +186,3 @@  SYM_FUNC_START_LOCAL(memcpy_orig)
 SYM_FUNC_END(memcpy_orig)
 
 .popsection
-
-#ifndef CONFIG_UML
-
-MCSAFE_TEST_CTL
-
-/*
- * __memcpy_mcsafe - memory copy with machine check exception handling
- * Note that we only catch machine checks when reading the source addresses.
- * Writes to target are posted and don't generate machine checks.
- */
-SYM_FUNC_START(__memcpy_mcsafe)
-	cmpl $8, %edx
-	/* Less than 8 bytes? Go to byte copy loop */
-	jb .L_no_whole_words
-
-	/* Check for bad alignment of source */
-	testl $7, %esi
-	/* Already aligned */
-	jz .L_8byte_aligned
-
-	/* Copy one byte at a time until source is 8-byte aligned */
-	movl %esi, %ecx
-	andl $7, %ecx
-	subl $8, %ecx
-	negl %ecx
-	subl %ecx, %edx
-.L_read_leading_bytes:
-	movb (%rsi), %al
-	MCSAFE_TEST_SRC %rsi 1 .E_leading_bytes
-	MCSAFE_TEST_DST %rdi 1 .E_leading_bytes
-.L_write_leading_bytes:
-	movb %al, (%rdi)
-	incq %rsi
-	incq %rdi
-	decl %ecx
-	jnz .L_read_leading_bytes
-
-.L_8byte_aligned:
-	movl %edx, %ecx
-	andl $7, %edx
-	shrl $3, %ecx
-	jz .L_no_whole_words
-
-.L_read_words:
-	movq (%rsi), %r8
-	MCSAFE_TEST_SRC %rsi 8 .E_read_words
-	MCSAFE_TEST_DST %rdi 8 .E_write_words
-.L_write_words:
-	movq %r8, (%rdi)
-	addq $8, %rsi
-	addq $8, %rdi
-	decl %ecx
-	jnz .L_read_words
-
-	/* Any trailing bytes? */
-.L_no_whole_words:
-	andl %edx, %edx
-	jz .L_done_memcpy_trap
-
-	/* Copy trailing bytes */
-	movl %edx, %ecx
-.L_read_trailing_bytes:
-	movb (%rsi), %al
-	MCSAFE_TEST_SRC %rsi 1 .E_trailing_bytes
-	MCSAFE_TEST_DST %rdi 1 .E_trailing_bytes
-.L_write_trailing_bytes:
-	movb %al, (%rdi)
-	incq %rsi
-	incq %rdi
-	decl %ecx
-	jnz .L_read_trailing_bytes
-
-	/* Copy successful. Return zero */
-.L_done_memcpy_trap:
-	xorl %eax, %eax
-.L_done:
-	ret
-SYM_FUNC_END(__memcpy_mcsafe)
-EXPORT_SYMBOL_GPL(__memcpy_mcsafe)
-
-	.section .fixup, "ax"
-	/*
-	 * Return number of bytes not copied for any failure. Note that
-	 * there is no "tail" handling since the source buffer is 8-byte
-	 * aligned and poison is cacheline aligned.
-	 */
-.E_read_words:
-	shll	$3, %ecx
-.E_leading_bytes:
-	addl	%edx, %ecx
-.E_trailing_bytes:
-	mov	%ecx, %eax
-	jmp	.L_done
-
-	/*
-	 * For write fault handling, given the destination is unaligned,
-	 * we handle faults on multi-byte writes with a byte-by-byte
-	 * copy up to the write-protected page.
-	 */
-.E_write_words:
-	shll	$3, %ecx
-	addl	%edx, %ecx
-	movl	%ecx, %edx
-	jmp mcsafe_handle_tail
-
-	.previous
-
-	_ASM_EXTABLE_FAULT(.L_read_leading_bytes, .E_leading_bytes)
-	_ASM_EXTABLE_FAULT(.L_read_words, .E_read_words)
-	_ASM_EXTABLE_FAULT(.L_read_trailing_bytes, .E_trailing_bytes)
-	_ASM_EXTABLE(.L_write_leading_bytes, .E_leading_bytes)
-	_ASM_EXTABLE(.L_write_words, .E_write_words)
-	_ASM_EXTABLE(.L_write_trailing_bytes, .E_trailing_bytes)
-#endif
diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c
index b0dfac3..5f1d4a9 100644
--- a/arch/x86/lib/usercopy_64.c
+++ b/arch/x86/lib/usercopy_64.c
@@ -56,27 +56,6 @@  unsigned long clear_user(void __user *to, unsigned long n)
 }
 EXPORT_SYMBOL(clear_user);
 
-/*
- * Similar to copy_user_handle_tail, probe for the write fault point,
- * but reuse __memcpy_mcsafe in case a new read error is encountered.
- * clac() is handled in _copy_to_iter_mcsafe().
- */
-__visible notrace unsigned long
-mcsafe_handle_tail(char *to, char *from, unsigned len)
-{
-	for (; len; --len, to++, from++) {
-		/*
-		 * Call the assembly routine back directly since
-		 * memcpy_mcsafe() may silently fallback to memcpy.
-		 */
-		unsigned long rem = __memcpy_mcsafe(to, from, 1);
-
-		if (rem)
-			break;
-	}
-	return len;
-}
-
 #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
 /**
  * clean_cache_range - write back a cache range with CLWB
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 86dbe0c..9fc18fa 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -49,7 +49,7 @@  do {								\
 #define pmem_assign(dest, src)	((dest) = (src))
 #endif
 
-#if defined(__HAVE_ARCH_MEMCPY_MCSAFE) && defined(DM_WRITECACHE_HAS_PMEM)
+#if IS_ENABLED(CONFIG_ARCH_HAS_COPY_MC) && defined(DM_WRITECACHE_HAS_PMEM)
 #define DM_WRITECACHE_HANDLE_HARDWARE_ERRORS
 #endif
 
@@ -984,7 +984,8 @@  static void writecache_resume(struct dm_target *ti)
 	}
 	wc->freelist_size = 0;
 
-	r = memcpy_mcsafe(&sb_seq_count, &sb(wc)->seq_count, sizeof(uint64_t));
+	r = copy_mc_to_kernel(&sb_seq_count, &sb(wc)->seq_count,
+			      sizeof(uint64_t));
 	if (r) {
 		writecache_error(wc, r, "hardware memory error when reading superblock: %d", r);
 		sb_seq_count = cpu_to_le64(0);
@@ -1000,7 +1001,8 @@  static void writecache_resume(struct dm_target *ti)
 			e->seq_count = -1;
 			continue;
 		}
-		r = memcpy_mcsafe(&wme, memory_entry(wc, e), sizeof(struct wc_memory_entry));
+		r = copy_mc_to_kernel(&wme, memory_entry(wc, e),
+				      sizeof(struct wc_memory_entry));
 		if (r) {
 			writecache_error(wc, r, "hardware memory error when reading metadata entry %lu: %d",
 					 (unsigned long)b, r);
@@ -1198,7 +1200,7 @@  static void bio_copy_block(struct dm_writecache *wc, struct bio *bio, void *data
 
 		if (rw == READ) {
 			int r;
-			r = memcpy_mcsafe(buf, data, size);
+			r = copy_mc_to_kernel(buf, data, size);
 			flush_dcache_page(bio_page(bio));
 			if (unlikely(r)) {
 				writecache_error(wc, r, "hardware memory error when reading data: %d", r);
@@ -2341,7 +2343,7 @@  invalid_optional:
 		}
 	}
 
-	r = memcpy_mcsafe(&s, sb(wc), sizeof(struct wc_memory_superblock));
+	r = copy_mc_to_kernel(&s, sb(wc), sizeof(struct wc_memory_superblock));
 	if (r) {
 		ti->error = "Hardware memory error when reading superblock";
 		goto bad;
@@ -2352,7 +2354,8 @@  invalid_optional:
 			ti->error = "Unable to initialize device";
 			goto bad;
 		}
-		r = memcpy_mcsafe(&s, sb(wc), sizeof(struct wc_memory_superblock));
+		r = copy_mc_to_kernel(&s, sb(wc),
+				      sizeof(struct wc_memory_superblock));
 		if (r) {
 			ti->error = "Hardware memory error when reading superblock";
 			goto bad;
diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c
index 45964ac..22d865b 100644
--- a/drivers/nvdimm/claim.c
+++ b/drivers/nvdimm/claim.c
@@ -268,7 +268,7 @@  static int nsio_rw_bytes(struct nd_namespace_common *ndns,
 	if (rw == READ) {
 		if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align)))
 			return -EIO;
-		if (memcpy_mcsafe(buf, nsio->addr + offset, size) != 0)
+		if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0)
 			return -EIO;
 		return 0;
 	}
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index fab29b5..5c6939e 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -125,7 +125,7 @@  static blk_status_t read_pmem(struct page *page, unsigned int off,
 	while (len) {
 		mem = kmap_atomic(page);
 		chunk = min_t(unsigned int, len, PAGE_SIZE - off);
-		rem = memcpy_mcsafe(mem + off, pmem_addr, chunk);
+		rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
 		kunmap_atomic(mem);
 		if (rem)
 			return BLK_STS_IOERR;
@@ -304,7 +304,7 @@  static long pmem_dax_direct_access(struct dax_device *dax_dev,
 
 /*
  * Use the 'no check' versions of copy_from_iter_flushcache() and
- * copy_to_iter_mcsafe() to bypass HARDENED_USERCOPY overhead. Bounds
+ * copy_mc_to_iter() to bypass HARDENED_USERCOPY overhead. Bounds
  * checking, both file offset and device offset, is handled by
  * dax_iomap_actor()
  */
@@ -317,7 +317,7 @@  static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 		void *addr, size_t bytes, struct iov_iter *i)
 {
-	return _copy_to_iter_mcsafe(addr, bytes, i);
+	return _copy_mc_to_iter(addr, bytes, i);
 }
 
 static const struct dax_operations pmem_dax_ops = {
diff --git a/include/linux/string.h b/include/linux/string.h
index 9b7a063..b1f3894 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -161,20 +161,13 @@  extern int bcmp(const void *,const void *,__kernel_size_t);
 #ifndef __HAVE_ARCH_MEMCHR
 extern void * memchr(const void *,int,__kernel_size_t);
 #endif
-#ifndef __HAVE_ARCH_MEMCPY_MCSAFE
-static inline __must_check unsigned long memcpy_mcsafe(void *dst,
-		const void *src, size_t cnt)
-{
-	memcpy(dst, src, cnt);
-	return 0;
-}
-#endif
 #ifndef __HAVE_ARCH_MEMCPY_FLUSHCACHE
 static inline void memcpy_flushcache(void *dst, const void *src, size_t cnt)
 {
 	memcpy(dst, src, cnt);
 }
 #endif
+
 void *memchr_inv(const void *s, int c, size_t n);
 char *strreplace(char *s, char old, char new);
 
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 94b2854..1ae36bc 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -179,6 +179,19 @@  copy_in_user(void __user *to, const void __user *from, unsigned long n)
 }
 #endif
 
+#ifndef copy_mc_to_kernel
+/*
+ * Without arch opt-in this generic copy_mc_to_kernel() will not handle
+ * #MC (or arch equivalent) during source read.
+ */
+static inline unsigned long __must_check
+copy_mc_to_kernel(void *dst, const void *src, size_t cnt)
+{
+	memcpy(dst, src, cnt);
+	return 0;
+}
+#endif
+
 static __always_inline void pagefault_disabled_inc(void)
 {
 	current->pagefault_disabled++;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 3835a8a..f14410c 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -185,10 +185,10 @@  size_t _copy_from_iter_flushcache(void *addr, size_t bytes, struct iov_iter *i);
 #define _copy_from_iter_flushcache _copy_from_iter_nocache
 #endif
 
-#ifdef CONFIG_ARCH_HAS_UACCESS_MCSAFE
-size_t _copy_to_iter_mcsafe(const void *addr, size_t bytes, struct iov_iter *i);
+#ifdef CONFIG_ARCH_HAS_COPY_MC
+size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i);
 #else
-#define _copy_to_iter_mcsafe _copy_to_iter
+#define _copy_mc_to_iter _copy_to_iter
 #endif
 
 static __always_inline __must_check
@@ -201,12 +201,12 @@  size_t copy_from_iter_flushcache(void *addr, size_t bytes, struct iov_iter *i)
 }
 
 static __always_inline __must_check
-size_t copy_to_iter_mcsafe(void *addr, size_t bytes, struct iov_iter *i)
+size_t copy_mc_to_iter(void *addr, size_t bytes, struct iov_iter *i)
 {
 	if (unlikely(!check_copy_size(addr, bytes, true)))
 		return 0;
 	else
-		return _copy_to_iter_mcsafe(addr, bytes, i);
+		return _copy_mc_to_iter(addr, bytes, i);
 }
 
 size_t iov_iter_zero(size_t bytes, struct iov_iter *);
diff --git a/lib/Kconfig b/lib/Kconfig
index b4b98a0..b46a9fd 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -635,7 +635,12 @@  config UACCESS_MEMCPY
 config ARCH_HAS_UACCESS_FLUSHCACHE
 	bool
 
-config ARCH_HAS_UACCESS_MCSAFE
+# arch has a concept of a recoverable synchronous exception due to a
+# memory-read error like x86 machine-check or ARM data-abort, and
+# implements copy_mc_to_{user,kernel} to abort and report
+# 'bytes-transferred' if that exception fires when accessing the source
+# buffer.
+config ARCH_HAS_COPY_MC
 	bool
 
 # Temporary. Goes away when all archs are cleaned up
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 5e40786..d13304a 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -637,30 +637,30 @@  size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
 }
 EXPORT_SYMBOL(_copy_to_iter);
 
-#ifdef CONFIG_ARCH_HAS_UACCESS_MCSAFE
-static int copyout_mcsafe(void __user *to, const void *from, size_t n)
+#ifdef CONFIG_ARCH_HAS_COPY_MC
+static int copyout_mc(void __user *to, const void *from, size_t n)
 {
 	if (access_ok(to, n)) {
 		instrument_copy_to_user(to, from, n);
-		n = copy_to_user_mcsafe((__force void *) to, from, n);
+		n = copy_mc_to_user((__force void *) to, from, n);
 	}
 	return n;
 }
 
-static unsigned long memcpy_mcsafe_to_page(struct page *page, size_t offset,
+static unsigned long copy_mc_to_page(struct page *page, size_t offset,
 		const char *from, size_t len)
 {
 	unsigned long ret;
 	char *to;
 
 	to = kmap_atomic(page);
-	ret = memcpy_mcsafe(to + offset, from, len);
+	ret = copy_mc_to_kernel(to + offset, from, len);
 	kunmap_atomic(to);
 
 	return ret;
 }
 
-static size_t copy_pipe_to_iter_mcsafe(const void *addr, size_t bytes,
+static size_t copy_mc_pipe_to_iter(const void *addr, size_t bytes,
 				struct iov_iter *i)
 {
 	struct pipe_inode_info *pipe = i->pipe;
@@ -678,7 +678,7 @@  static size_t copy_pipe_to_iter_mcsafe(const void *addr, size_t bytes,
 		size_t chunk = min_t(size_t, n, PAGE_SIZE - off);
 		unsigned long rem;
 
-		rem = memcpy_mcsafe_to_page(pipe->bufs[i_head & p_mask].page,
+		rem = copy_mc_to_page(pipe->bufs[i_head & p_mask].page,
 					    off, addr, chunk);
 		i->head = i_head;
 		i->iov_offset = off + chunk - rem;
@@ -695,18 +695,17 @@  static size_t copy_pipe_to_iter_mcsafe(const void *addr, size_t bytes,
 }
 
 /**
- * _copy_to_iter_mcsafe - copy to user with source-read error exception handling
+ * _copy_mc_to_iter - copy to iter with source memory error exception handling
  * @addr: source kernel address
  * @bytes: total transfer length
  * @iter: destination iterator
  *
- * The pmem driver arranges for filesystem-dax to use this facility via
- * dax_copy_to_iter() for protecting read/write to persistent memory.
- * Unless / until an architecture can guarantee identical performance
- * between _copy_to_iter_mcsafe() and _copy_to_iter() it would be a
- * performance regression to switch more users to the mcsafe version.
+ * The pmem driver deploys this for the dax operation
+ * (dax_copy_to_iter()) for dax reads (bypass page-cache and the
+ * block-layer). Upon #MC read(2) aborts and returns EIO or the bytes
+ * successfully copied.
  *
- * Otherwise, the main differences between this and typical _copy_to_iter().
+ * The main differences between this and typical _copy_to_iter().
  *
  * * Typical tail/residue handling after a fault retries the copy
  *   byte-by-byte until the fault happens again. Re-triggering machine
@@ -717,23 +716,22 @@  static size_t copy_pipe_to_iter_mcsafe(const void *addr, size_t bytes,
  * * ITER_KVEC, ITER_PIPE, and ITER_BVEC can return short copies.
  *   Compare to copy_to_iter() where only ITER_IOVEC attempts might return
  *   a short copy.
- *
- * See MCSAFE_TEST for self-test.
  */
-size_t _copy_to_iter_mcsafe(const void *addr, size_t bytes, struct iov_iter *i)
+size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
 {
 	const char *from = addr;
 	unsigned long rem, curr_addr, s_addr = (unsigned long) addr;
 
 	if (unlikely(iov_iter_is_pipe(i)))
-		return copy_pipe_to_iter_mcsafe(addr, bytes, i);
+		return copy_mc_pipe_to_iter(addr, bytes, i);
 	if (iter_is_iovec(i))
 		might_fault();
 	iterate_and_advance(i, bytes, v,
-		copyout_mcsafe(v.iov_base, (from += v.iov_len) - v.iov_len, v.iov_len),
+		copyout_mc(v.iov_base, (from += v.iov_len) - v.iov_len,
+			   v.iov_len),
 		({
-		rem = memcpy_mcsafe_to_page(v.bv_page, v.bv_offset,
-                               (from += v.bv_len) - v.bv_len, v.bv_len);
+		rem = copy_mc_to_page(v.bv_page, v.bv_offset,
+				      (from += v.bv_len) - v.bv_len, v.bv_len);
 		if (rem) {
 			curr_addr = (unsigned long) from;
 			bytes = curr_addr - s_addr - rem;
@@ -741,8 +739,8 @@  size_t _copy_to_iter_mcsafe(const void *addr, size_t bytes, struct iov_iter *i)
 		}
 		}),
 		({
-		rem = memcpy_mcsafe(v.iov_base, (from += v.iov_len) - v.iov_len,
-				v.iov_len);
+		rem = copy_mc_to_kernel(v.iov_base, (from += v.iov_len)
+					- v.iov_len, v.iov_len);
 		if (rem) {
 			curr_addr = (unsigned long) from;
 			bytes = curr_addr - s_addr - rem;
@@ -753,8 +751,8 @@  size_t _copy_to_iter_mcsafe(const void *addr, size_t bytes, struct iov_iter *i)
 
 	return bytes;
 }
-EXPORT_SYMBOL_GPL(_copy_to_iter_mcsafe);
-#endif /* CONFIG_ARCH_HAS_UACCESS_MCSAFE */
+EXPORT_SYMBOL_GPL(_copy_mc_to_iter);
+#endif /* CONFIG_ARCH_HAS_COPY_MC */
 
 size_t _copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
 {
diff --git a/tools/arch/x86/include/asm/mcsafe_test.h b/tools/arch/x86/include/asm/mcsafe_test.h
deleted file mode 100644
index 2ccd588..0000000
--- a/tools/arch/x86/include/asm/mcsafe_test.h
+++ /dev/null
@@ -1,13 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _MCSAFE_TEST_H_
-#define _MCSAFE_TEST_H_
-
-.macro MCSAFE_TEST_CTL
-.endm
-
-.macro MCSAFE_TEST_SRC reg count target
-.endm
-
-.macro MCSAFE_TEST_DST reg count target
-.endm
-#endif /* _MCSAFE_TEST_H_ */
diff --git a/tools/arch/x86/lib/memcpy_64.S b/tools/arch/x86/lib/memcpy_64.S
index 45f8e1b..0b5b8ae 100644
--- a/tools/arch/x86/lib/memcpy_64.S
+++ b/tools/arch/x86/lib/memcpy_64.S
@@ -4,7 +4,6 @@ 
 #include <linux/linkage.h>
 #include <asm/errno.h>
 #include <asm/cpufeatures.h>
-#include <asm/mcsafe_test.h>
 #include <asm/alternative-asm.h>
 #include <asm/export.h>
 
@@ -187,117 +186,3 @@  SYM_FUNC_START(memcpy_orig)
 SYM_FUNC_END(memcpy_orig)
 
 .popsection
-
-#ifndef CONFIG_UML
-
-MCSAFE_TEST_CTL
-
-/*
- * __memcpy_mcsafe - memory copy with machine check exception handling
- * Note that we only catch machine checks when reading the source addresses.
- * Writes to target are posted and don't generate machine checks.
- */
-SYM_FUNC_START(__memcpy_mcsafe)
-	cmpl $8, %edx
-	/* Less than 8 bytes? Go to byte copy loop */
-	jb .L_no_whole_words
-
-	/* Check for bad alignment of source */
-	testl $7, %esi
-	/* Already aligned */
-	jz .L_8byte_aligned
-
-	/* Copy one byte at a time until source is 8-byte aligned */
-	movl %esi, %ecx
-	andl $7, %ecx
-	subl $8, %ecx
-	negl %ecx
-	subl %ecx, %edx
-.L_read_leading_bytes:
-	movb (%rsi), %al
-	MCSAFE_TEST_SRC %rsi 1 .E_leading_bytes
-	MCSAFE_TEST_DST %rdi 1 .E_leading_bytes
-.L_write_leading_bytes:
-	movb %al, (%rdi)
-	incq %rsi
-	incq %rdi
-	decl %ecx
-	jnz .L_read_leading_bytes
-
-.L_8byte_aligned:
-	movl %edx, %ecx
-	andl $7, %edx
-	shrl $3, %ecx
-	jz .L_no_whole_words
-
-.L_read_words:
-	movq (%rsi), %r8
-	MCSAFE_TEST_SRC %rsi 8 .E_read_words
-	MCSAFE_TEST_DST %rdi 8 .E_write_words
-.L_write_words:
-	movq %r8, (%rdi)
-	addq $8, %rsi
-	addq $8, %rdi
-	decl %ecx
-	jnz .L_read_words
-
-	/* Any trailing bytes? */
-.L_no_whole_words:
-	andl %edx, %edx
-	jz .L_done_memcpy_trap
-
-	/* Copy trailing bytes */
-	movl %edx, %ecx
-.L_read_trailing_bytes:
-	movb (%rsi), %al
-	MCSAFE_TEST_SRC %rsi 1 .E_trailing_bytes
-	MCSAFE_TEST_DST %rdi 1 .E_trailing_bytes
-.L_write_trailing_bytes:
-	movb %al, (%rdi)
-	incq %rsi
-	incq %rdi
-	decl %ecx
-	jnz .L_read_trailing_bytes
-
-	/* Copy successful. Return zero */
-.L_done_memcpy_trap:
-	xorl %eax, %eax
-.L_done:
-	ret
-SYM_FUNC_END(__memcpy_mcsafe)
-EXPORT_SYMBOL_GPL(__memcpy_mcsafe)
-
-	.section .fixup, "ax"
-	/*
-	 * Return number of bytes not copied for any failure. Note that
-	 * there is no "tail" handling since the source buffer is 8-byte
-	 * aligned and poison is cacheline aligned.
-	 */
-.E_read_words:
-	shll	$3, %ecx
-.E_leading_bytes:
-	addl	%edx, %ecx
-.E_trailing_bytes:
-	mov	%ecx, %eax
-	jmp	.L_done
-
-	/*
-	 * For write fault handling, given the destination is unaligned,
-	 * we handle faults on multi-byte writes with a byte-by-byte
-	 * copy up to the write-protected page.
-	 */
-.E_write_words:
-	shll	$3, %ecx
-	addl	%edx, %ecx
-	movl	%ecx, %edx
-	jmp mcsafe_handle_tail
-
-	.previous
-
-	_ASM_EXTABLE_FAULT(.L_read_leading_bytes, .E_leading_bytes)
-	_ASM_EXTABLE_FAULT(.L_read_words, .E_read_words)
-	_ASM_EXTABLE_FAULT(.L_read_trailing_bytes, .E_trailing_bytes)
-	_ASM_EXTABLE(.L_write_leading_bytes, .E_leading_bytes)
-	_ASM_EXTABLE(.L_write_words, .E_write_words)
-	_ASM_EXTABLE(.L_write_trailing_bytes, .E_trailing_bytes)
-#endif
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e034a8f..893f021 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -548,8 +548,8 @@  static const char *uaccess_safe_builtin[] = {
 	"__ubsan_handle_shift_out_of_bounds",
 	/* misc */
 	"csum_partial_copy_generic",
-	"__memcpy_mcsafe",
-	"mcsafe_handle_tail",
+	"copy_mc_fragile",
+	"copy_mc_fragile_handle_tail",
 	"ftrace_likely_update", /* CONFIG_TRACE_BRANCH_PROFILING */
 	NULL
 };
diff --git a/tools/perf/bench/Build b/tools/perf/bench/Build
index dd68a40..878db6a 100644
--- a/tools/perf/bench/Build
+++ b/tools/perf/bench/Build
@@ -13,7 +13,6 @@  perf-y += synthesize.o
 perf-y += kallsyms-parse.o
 perf-y += find-bit-bench.o
 
-perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-lib.o
 perf-$(CONFIG_X86_64) += mem-memcpy-x86-64-asm.o
 perf-$(CONFIG_X86_64) += mem-memset-x86-64-asm.o
 
diff --git a/tools/perf/bench/mem-memcpy-x86-64-lib.c b/tools/perf/bench/mem-memcpy-x86-64-lib.c
deleted file mode 100644
index 4130734..0000000
--- a/tools/perf/bench/mem-memcpy-x86-64-lib.c
+++ /dev/null
@@ -1,24 +0,0 @@ 
-/*
- * From code in arch/x86/lib/usercopy_64.c, copied to keep tools/ copy
- * of the kernel's arch/x86/lib/memcpy_64.s used in 'perf bench mem memcpy'
- * happy.
- */
-#include <linux/types.h>
-
-unsigned long __memcpy_mcsafe(void *dst, const void *src, size_t cnt);
-unsigned long mcsafe_handle_tail(char *to, char *from, unsigned len);
-
-unsigned long mcsafe_handle_tail(char *to, char *from, unsigned len)
-{
-	for (; len; --len, to++, from++) {
-		/*
-		 * Call the assembly routine back directly since
-		 * memcpy_mcsafe() may silently fallback to memcpy.
-		 */
-		unsigned long rem = __memcpy_mcsafe(to, from, 1);
-
-		if (rem)
-			break;
-	}
-	return len;
-}
diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index a1a5dc6..2ac0fff 100644
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -23,7 +23,8 @@ 
 #include "nfit_test.h"
 #include "../watermark.h"
 
-#include <asm/mcsafe_test.h>
+#include <asm/copy_mc_test.h>
+#include <asm/mce.h>
 
 /*
  * Generate an NFIT table to describe the following topology:
@@ -3283,7 +3284,7 @@  static struct platform_driver nfit_test_driver = {
 	.id_table = nfit_test_id,
 };
 
-static char mcsafe_buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
+static char copy_mc_buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
 
 enum INJECT {
 	INJECT_NONE,
@@ -3291,7 +3292,7 @@  enum INJECT {
 	INJECT_DST,
 };
 
-static void mcsafe_test_init(char *dst, char *src, size_t size)
+static void copy_mc_test_init(char *dst, char *src, size_t size)
 {
 	size_t i;
 
@@ -3300,7 +3301,7 @@  static void mcsafe_test_init(char *dst, char *src, size_t size)
 		src[i] = (char) i;
 }
 
-static bool mcsafe_test_validate(unsigned char *dst, unsigned char *src,
+static bool copy_mc_test_validate(unsigned char *dst, unsigned char *src,
 		size_t size, unsigned long rem)
 {
 	size_t i;
@@ -3321,12 +3322,12 @@  static bool mcsafe_test_validate(unsigned char *dst, unsigned char *src,
 	return true;
 }
 
-void mcsafe_test(void)
+void copy_mc_test(void)
 {
 	char *inject_desc[] = { "none", "source", "destination" };
 	enum INJECT inj;
 
-	if (IS_ENABLED(CONFIG_MCSAFE_TEST)) {
+	if (IS_ENABLED(CONFIG_COPY_MC_TEST)) {
 		pr_info("%s: run...\n", __func__);
 	} else {
 		pr_info("%s: disabled, skip.\n", __func__);
@@ -3344,31 +3345,31 @@  void mcsafe_test(void)
 
 			switch (inj) {
 			case INJECT_NONE:
-				mcsafe_inject_src(NULL);
-				mcsafe_inject_dst(NULL);
-				dst = &mcsafe_buf[2048];
-				src = &mcsafe_buf[1024 - i];
+				copy_mc_inject_src(NULL);
+				copy_mc_inject_dst(NULL);
+				dst = &copy_mc_buf[2048];
+				src = &copy_mc_buf[1024 - i];
 				expect = 0;
 				break;
 			case INJECT_SRC:
-				mcsafe_inject_src(&mcsafe_buf[1024]);
-				mcsafe_inject_dst(NULL);
-				dst = &mcsafe_buf[2048];
-				src = &mcsafe_buf[1024 - i];
+				copy_mc_inject_src(&copy_mc_buf[1024]);
+				copy_mc_inject_dst(NULL);
+				dst = &copy_mc_buf[2048];
+				src = &copy_mc_buf[1024 - i];
 				expect = 512 - i;
 				break;
 			case INJECT_DST:
-				mcsafe_inject_src(NULL);
-				mcsafe_inject_dst(&mcsafe_buf[2048]);
-				dst = &mcsafe_buf[2048 - i];
-				src = &mcsafe_buf[1024];
+				copy_mc_inject_src(NULL);
+				copy_mc_inject_dst(&copy_mc_buf[2048]);
+				dst = &copy_mc_buf[2048 - i];
+				src = &copy_mc_buf[1024];
 				expect = 512 - i;
 				break;
 			}
 
-			mcsafe_test_init(dst, src, 512);
-			rem = __memcpy_mcsafe(dst, src, 512);
-			valid = mcsafe_test_validate(dst, src, 512, expect);
+			copy_mc_test_init(dst, src, 512);
+			rem = copy_mc_fragile(dst, src, 512);
+			valid = copy_mc_test_validate(dst, src, 512, expect);
 			if (rem == expect && valid)
 				continue;
 			pr_info("%s: copy(%#lx, %#lx, %d) off: %d rem: %ld %s expect: %ld\n",
@@ -3380,8 +3381,8 @@  void mcsafe_test(void)
 		}
 	}
 
-	mcsafe_inject_src(NULL);
-	mcsafe_inject_dst(NULL);
+	copy_mc_inject_src(NULL);
+	copy_mc_inject_dst(NULL);
 }
 
 static __init int nfit_test_init(void)
@@ -3392,7 +3393,7 @@  static __init int nfit_test_init(void)
 	libnvdimm_test();
 	acpi_nfit_test();
 	device_dax_test();
-	mcsafe_test();
+	copy_mc_test();
 	dax_pmem_test();
 	dax_pmem_core_test();
 #ifdef CONFIG_DEV_DAX_PMEM_COMPAT
diff --git a/tools/testing/selftests/powerpc/copyloops/.gitignore b/tools/testing/selftests/powerpc/copyloops/.gitignore
index ddaf140..994b11a 100644
--- a/tools/testing/selftests/powerpc/copyloops/.gitignore
+++ b/tools/testing/selftests/powerpc/copyloops/.gitignore
@@ -12,4 +12,4 @@  memcpy_p7_t1
 copyuser_64_exc_t0
 copyuser_64_exc_t1
 copyuser_64_exc_t2
-memcpy_mcsafe_64
+copy_mc_64
diff --git a/tools/testing/selftests/powerpc/copyloops/Makefile b/tools/testing/selftests/powerpc/copyloops/Makefile
index 0917983..3095b1f 100644
--- a/tools/testing/selftests/powerpc/copyloops/Makefile
+++ b/tools/testing/selftests/powerpc/copyloops/Makefile
@@ -12,7 +12,7 @@  ASFLAGS = $(CFLAGS) -Wa,-mpower4
 TEST_GEN_PROGS := copyuser_64_t0 copyuser_64_t1 copyuser_64_t2 \
 		copyuser_p7_t0 copyuser_p7_t1 \
 		memcpy_64_t0 memcpy_64_t1 memcpy_64_t2 \
-		memcpy_p7_t0 memcpy_p7_t1 memcpy_mcsafe_64 \
+		memcpy_p7_t0 memcpy_p7_t1 copy_mc_64 \
 		copyuser_64_exc_t0 copyuser_64_exc_t1 copyuser_64_exc_t2
 
 EXTRA_SOURCES := validate.c ../harness.c stubs.S
@@ -45,9 +45,9 @@  $(OUTPUT)/memcpy_p7_t%:	memcpy_power7.S $(EXTRA_SOURCES)
 		-D SELFTEST_CASE=$(subst memcpy_p7_t,,$(notdir $@)) \
 		-o $@ $^
 
-$(OUTPUT)/memcpy_mcsafe_64: memcpy_mcsafe_64.S $(EXTRA_SOURCES)
+$(OUTPUT)/copy_mc_64: copy_mc_64.S $(EXTRA_SOURCES)
 	$(CC) $(CPPFLAGS) $(CFLAGS) \
-		-D COPY_LOOP=test_memcpy_mcsafe \
+		-D COPY_LOOP=test_copy_mc_generic \
 		-o $@ $^
 
 $(OUTPUT)/copyuser_64_exc_t%: copyuser_64.S exc_validate.c ../harness.c \
diff --git a/tools/testing/selftests/powerpc/copyloops/copy_mc_64.S b/tools/testing/selftests/powerpc/copyloops/copy_mc_64.S
new file mode 120000
index 0000000..dcbe06d
--- /dev/null
+++ b/tools/testing/selftests/powerpc/copyloops/copy_mc_64.S
@@ -0,0 +1 @@ 
+../../../../../arch/powerpc/lib/copy_mc_64.S
\ No newline at end of file
diff --git a/tools/testing/selftests/powerpc/copyloops/memcpy_mcsafe_64.S b/tools/testing/selftests/powerpc/copyloops/memcpy_mcsafe_64.S
deleted file mode 120000
index f0feef3..0000000
--- a/tools/testing/selftests/powerpc/copyloops/memcpy_mcsafe_64.S
+++ /dev/null
@@ -1 +0,0 @@ 
-../../../../../arch/powerpc/lib/memcpy_mcsafe_64.S
\ No newline at end of file