[PATCH reworded] x86/kbuild: enable modversions for symbols exported from asm

From: Adam Borowski <kilobyte@angband.pl>
To: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Nicholas Piggin <npiggin@gmail.com>,
	Peter Wu <peter@lekensteyn.nl>,
	Vince Weaver <vincent.weaver@maine.edu>,
	Michal Marek <mmarek@suse.com>, Al Viro <viro@zeniv.linux.org.uk>,
	Oliver Hartkopp <socketcan@hartkopp.net>,
	linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org,
	linux-arch@vger.kernel.org, regressions@leemhuis.info
Cc: Adam Borowski <kilobyte@angband.pl>
Subject: [PATCH reworded] x86/kbuild: enable modversions for symbols exported from asm
Date: Mon, 21 Nov 2016 15:52:20 +0100	[thread overview]
Message-ID: <20161121145220.10430-1-kilobyte@angband.pl> (raw)
In-Reply-To: <20161121182714.2cd5da75@roar.ozlabs.ibm.com>

Commit 4efca4ed ("kbuild: modversions for EXPORT_SYMBOL() for asm") adds
modversion support for symbols exported from asm files. Architectures
must include C-style declarations for those symbols in asm/asm-prototypes.h
in order for them to be versioned.

Add these declarations for x86, and an architecture-independent file that
can be used for common symbols.

User impact: kernels may fail to load modules at all when
CONFIG_MODVERSIONS=y.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Tested-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Peter Wu <oeter@lekensteyn.nl>
---
 arch/x86/include/asm/asm-prototypes.h | 12 ++++++++++++
 include/asm-generic/asm-prototypes.h  |  7 +++++++
 2 files changed, 19 insertions(+)
 create mode 100644 arch/x86/include/asm/asm-prototypes.h
 create mode 100644 include/asm-generic/asm-prototypes.h

diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h
new file mode 100644
index 0000000..ae87224
--- /dev/null
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -0,0 +1,12 @@
+#include <asm/ftrace.h>
+#include <asm/uaccess.h>
+#include <asm/string.h>
+#include <asm/page.h>
+#include <asm/checksum.h>
+
+#include <asm-generic/asm-prototypes.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/special_insns.h>
+#include <asm/preempt.h>
diff --git a/include/asm-generic/asm-prototypes.h b/include/asm-generic/asm-prototypes.h
new file mode 100644
index 0000000..df13637
--- /dev/null
+++ b/include/asm-generic/asm-prototypes.h
@@ -0,0 +1,7 @@
+#include <linux/bitops.h>
+extern void *__memset(void *, int, __kernel_size_t);
+extern void *__memcpy(void *, const void *, __kernel_size_t);
+extern void *__memmove(void *, const void *, __kernel_size_t);
+extern void *memset(void *, int, __kernel_size_t);
+extern void *memcpy(void *, const void *, __kernel_size_t);
+extern void *memmove(void *, const void *, __kernel_size_t);
-- 
2.10.2

Now with a better description, provided by Nick Piggin (thanks!), and a
remark about user impact.

This version doesn't split the patch between x86 vs generic parts, would you
guys prefer that?
