The patch titled
Subject: byteorder: sanity check toolchain vs kernel endianess
has been added to the -mm tree. Its filename is
byteorder-sanity-check-toolchain-vs-kernel-endianess.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/byteorder-sanity-check-toolchain-vs-kernel-endianess.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/byteorder-sanity-check-toolchain-vs-kernel-endianess.patch
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------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: byteorder: sanity check toolchain vs kernel endianess
When removing some dead big endian checks in the RISC-V code Nick
suggested that we should have some generic sanity checks. I don't think
we should have thos inside the RISC-V code, but maybe it might make sense
to have these in the generic byteorder headers. Note that these are UAPI
headers and some compilers might not actually define __BYTE_ORDER__, so we
first check that it actually exists.
Link: http://lkml.kernel.org/r/20190412143538.11780-1-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Suggested-by: Nick Kossifidis <mick@xxxxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/uapi/linux/byteorder/big_endian.h | 4 ++++
include/uapi/linux/byteorder/little_endian.h | 4 ++++
2 files changed, 8 insertions(+)
--- a/include/uapi/linux/byteorder/big_endian.h~byteorder-sanity-check-toolchain-vs-kernel-endianess
+++ a/include/uapi/linux/byteorder/big_endian.h
@@ -2,6 +2,10 @@
#ifndef _UAPI_LINUX_BYTEORDER_BIG_ENDIAN_H
#define _UAPI_LINUX_BYTEORDER_BIG_ENDIAN_H
+#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ != __ORDER_BIG_ENDIAN__
+#error "Unsupported endianess, check your toolchain"
+#endif
+
#ifndef __BIG_ENDIAN
#define __BIG_ENDIAN 4321
#endif
--- a/include/uapi/linux/byteorder/little_endian.h~byteorder-sanity-check-toolchain-vs-kernel-endianess
+++ a/include/uapi/linux/byteorder/little_endian.h
@@ -2,6 +2,10 @@
#ifndef _UAPI_LINUX_BYTEORDER_LITTLE_ENDIAN_H
#define _UAPI_LINUX_BYTEORDER_LITTLE_ENDIAN_H
+#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
+#error "Unsupported endianess, check your toolchain"
+#endif
+
#ifndef __LITTLE_ENDIAN
#define __LITTLE_ENDIAN 1234
#endif
_
Patches currently in -mm which might be from hch@xxxxxx are
initramfs-free-initrd-memory-if-opening-initrdimage-fails.patch
initramfs-cleanup-initrd-freeing.patch
initramfs-factor-out-a-helper-to-populate-the-initrd-image.patch
initramfs-cleanup-populate_rootfs.patch
initramfs-move-the-legacy-keepinitrd-parameter-to-core-code.patch
initramfs-proide-a-generic-free_initrd_mem-implementation.patch
initramfs-poison-freed-initrd-memory.patch
byteorder-sanity-check-toolchain-vs-kernel-endianess.patch
