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Date:   Wed, 7 Oct 2020 19:03:05 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     linux-tip-commits@vger.kernel.org, Tony Luck <tony.luck@intel.com>,
        Michael Ellerman <mpe@ellerman.id.au>, stable@vger.kernel.org,
        x86 <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [tip: ras/core] x86, powerpc: Rename memcpy_mcsafe() to
 copy_mc_to_{user, kernel}()
Message-ID: <20201007170305.GK5607@zn.tnic>
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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.

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