x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm

commit b9e705ef7cfaf22db0daab91ad3cd33b0fa32eb9 upstream.

Where an ALTERNATIVE is used in the middle of an inline asm block, this
would otherwise lead to the following instruction being appended directly
to the trailing ".popsection", and a failed compile.

Fixes: 9cebed423c84 ("x86, alternative: Use .pushsection/.popsection")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: ak@linux.intel.com
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180104143710.8961-8-dwmw@amazon.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index 09936e9c8154fe2fd357aadc45f88daf62fae920..d1cf17173b1b0c7886cc0a812b613f9cf9df405a 100644 (file)
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -138,7 +138,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
        ".popsection\n"                                                 \
        ".pushsection .altinstr_replacement, \"ax\"\n"                  \
        ALTINSTR_REPLACEMENT(newinstr, feature, 1)                      \
-       ".popsection"
+       ".popsection\n"
 
 #define ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2)\
        OLDINSTR_2(oldinstr, 1, 2)                                      \
@@ -149,7 +149,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
        ".pushsection .altinstr_replacement, \"ax\"\n"                  \
        ALTINSTR_REPLACEMENT(newinstr1, feature1, 1)                    \
        ALTINSTR_REPLACEMENT(newinstr2, feature2, 2)                    \
-       ".popsection"
+       ".popsection\n"
 
 /*
  * This must be included *after* the definition of ALTERNATIVE due to