From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        John Fastabend <john.fastabend@gmail.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Dave Hansen <dave.hansen@linux.intel.com>
Cc:     Viresh Kumar <viresh.kumar@linaro.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] bpf: Fix undeclared function 'barrier_nospec' warning
Date:   Wed, 22 Feb 2023 13:54:31 +0530
Message-Id: <9c476aa64c9588205817833dbaa622f87c0e0081.1677051600.git.viresh.kumar@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add the missing header for architectures that don't define
the barrier_nospec() macro. The nospec.h header is added after the
inclusion of barrier.h to avoid redefining the macro for architectures
that already define barrier_nospec() in their respective barrier.h
headers.

Fixes: 74e19ef0ff80 ("uaccess: Add speculation barrier to copy_from_user()")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
Linus's master branch fails currently to build for arm64 without this commit.

 kernel/bpf/core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 933869983e2a..92aeb388e422 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -38,6 +38,8 @@
 #include <linux/memcontrol.h>
 
 #include <asm/barrier.h>
+#include <linux/nospec.h>
+
 #include <asm/unaligned.h>
 
 /* Registers */
-- 
2.31.1.272.g89b43f80a514