[PATCH 2/6] uaccess: add untagged_addr definition for other arches

From: Andrey Konovalov <andreyknvl@google.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Mark Rutland <mark.rutland@arm.com>,
	Robin Murphy <robin.murphy@arm.com>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Andrey Konovalov <andreyknvl@google.com>,
	James Morse <james.morse@arm.com>,
	Kees Cook <keescook@chromium.org>,
	Bart Van Assche <bart.vanassche@wdc.com>,
	Kate Stewart <kstewart@linuxfoundation.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Philippe Ombredanne <pombredanne@nexb.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Ingo Molnar <mingo@kernel.org>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
	Dan Williams <dan.j.williams@intel.com>,
	"Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
	Zi Yan <zi.yan@cs.rutgers.edu>,
	linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Dmitry Vyukov <dvyukov@google.com>,
	Kostya Serebryany <kcc@google.com>,
	Evgeniy Stepanov <eugenis@google.com>,
	Lee Smith <Lee.Smith@arm.com>,
	Ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>,
	Jacob Bramley <Jacob.Bramley@arm.com>,
	Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>
Subject: [PATCH 2/6] uaccess: add untagged_addr definition for other arches
Date: Wed, 18 Apr 2018 20:53:11 +0200	[thread overview]
Message-ID: <3001f7c75f1f99b4c7b789cf91da06678df3435e.1524077494.git.andreyknvl@google.com> (raw)
In-Reply-To: <cover.1524077494.git.andreyknvl@google.com>
In-Reply-To: <cover.1524077494.git.andreyknvl@google.com>

To allow arm64 syscalls accept tagged pointers from userspace, we must
untag them when they are passed to the kernel. Since untagging is done in
generic parts of the kernel (like the mm subsystem), the untagged_addr
macro should be defined for all architectures.

Define it as a noop for other architectures besides arm64.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 include/linux/uaccess.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index efe79c1cdd47..c045b4eff95e 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -13,6 +13,10 @@
 
 #include <asm/uaccess.h>
 
+#ifndef untagged_addr
+#define untagged_addr(addr) addr
+#endif
+
 /*
  * Architectures should provide two primitives (raw_copy_{to,from}_user())
  * and get rid of their private instances of copy_{to,from}_user() and
-- 
2.17.0.484.g0c8726318c-goog
