kernel: use upstream patches for musl

This replaces the current patches used to make the kernel headers
compatible with musl with the version which was accepted upstream. This
is included in upstream kernel 4.15.
This was compile tested with iproute2 build on all supported kernel
versions with musl and one one with glibc.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 102 insertions, 0 deletions

diff --git a/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch b/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch
new file mode 100644
index 0000000000..67895995b2
--- /dev/null
+++ b/target/linux/generic/pending-3.18/270-uapi-libc-compat-add-fallback-for-unsupported-libcs.patch
@@ -0,0 +1,102 @@
+From c6bdd0d302119819de72439972d0462c26ef9eda Mon Sep 17 00:00:00 2001
+From: Felix Janda <felix.janda@posteo.de>
+Date: Sun, 12 Nov 2017 13:30:17 -0500
+Subject: uapi libc compat: add fallback for unsupported libcs
+
+libc-compat.h aims to prevent symbol collisions between uapi and libc
+headers for each supported libc. This requires continuous coordination
+between them.
+
+The goal of this commit is to improve the situation for libcs (such as
+musl) which are not yet supported and/or do not wish to be explicitly
+supported, while not affecting supported libcs. More precisely, with
+this commit, unsupported libcs can request the suppression of any
+specific uapi definition by defining the correspondings _UAPI_DEF_*
+macro as 0. This can fix symbol collisions for them, as long as the
+libc headers are included before the uapi headers. Inclusion in the
+other order is outside the scope of this commit.
+
+All infrastructure in order to enable this fallback for unsupported
+libcs is already in place, except that libc-compat.h unconditionally
+defines all _UAPI_DEF_* macros to 1 for all unsupported libcs so that
+any previous definitions are ignored. In order to fix this, this commit
+merely makes these definitions conditional.
+
+This commit together with the musl libc commit
+
+http://git.musl-libc.org/cgit/musl/commit/?id=04983f2272382af92eb8f8838964ff944fbb8258
+
+fixes for example the following compiler errors when <linux/in6.h> is
+included after musl's <netinet/in.h>:
+
+./linux/in6.h:32:8: error: redefinition of 'struct in6_addr'
+./linux/in6.h:49:8: error: redefinition of 'struct sockaddr_in6'
+./linux/in6.h:59:8: error: redefinition of 'struct ipv6_mreq'
+
+The comments referencing glibc are still correct, but this file is not
+only used for glibc any more.
+
+Signed-off-by: Felix Janda <felix.janda@posteo.de>
+Reviewed-by: Hauke Mehrtens <hauke@hauke-m.de>
+---
+ include/uapi/linux/libc-compat.h | 55 +++++++++++++++++++++++++++++++++++++++-
+ 1 file changed, 54 insertions(+), 1 deletion(-)
+
+--- a/include/uapi/linux/libc-compat.h
++++ b/include/uapi/linux/libc-compat.h
+@@ -110,27 +110,54 @@
+ 
+ /* If we did not see any headers from any supported C libraries,
+  * or we are being included in the kernel, then define everything
+- * that we need. */
++ * that we need. Check for previous __UAPI_* definitions to give
++ * unsupported C libraries a way to opt out of any kernel definition. */
+ #else /* !defined(__GLIBC__) */
+ 
+ /* Definitions for in.h */
++#ifndef __UAPI_DEF_IN_ADDR
+ #define __UAPI_DEF_IN_ADDR		1
++#endif
++#ifndef __UAPI_DEF_IN_IPPROTO
+ #define __UAPI_DEF_IN_IPPROTO		1
++#endif
++#ifndef __UAPI_DEF_IN_PKTINFO
+ #define __UAPI_DEF_IN_PKTINFO		1
++#endif
++#ifndef __UAPI_DEF_IP_MREQ
+ #define __UAPI_DEF_IP_MREQ		1
++#endif
++#ifndef __UAPI_DEF_SOCKADDR_IN
+ #define __UAPI_DEF_SOCKADDR_IN		1
++#endif
++#ifndef __UAPI_DEF_IN_CLASS
+ #define __UAPI_DEF_IN_CLASS		1
++#endif
+ 
+ /* Definitions for in6.h */
++#ifndef __UAPI_DEF_IN6_ADDR
+ #define __UAPI_DEF_IN6_ADDR		1
++#endif
++#ifndef __UAPI_DEF_IN6_ADDR_ALT
+ #define __UAPI_DEF_IN6_ADDR_ALT		1
++#endif
++#ifndef __UAPI_DEF_SOCKADDR_IN6
+ #define __UAPI_DEF_SOCKADDR_IN6		1
++#endif
++#ifndef __UAPI_DEF_IPV6_MREQ
+ #define __UAPI_DEF_IPV6_MREQ		1
++#endif
++#ifndef __UAPI_DEF_IPPROTO_V6
+ #define __UAPI_DEF_IPPROTO_V6		1
++#endif
++#ifndef __UAPI_DEF_IPV6_OPTIONS
+ #define __UAPI_DEF_IPV6_OPTIONS		1
++#endif
+ 
+ /* Definitions for xattr.h */
++#ifndef __UAPI_DEF_XATTR
+ #define __UAPI_DEF_XATTR		1
++#endif
+ 
+ #endif /* __GLIBC__ */
+