patches: arm64: Fix linux and linux-next

See the patch for full details. We will revert this when it hits
mainline but we shouldn't hold up CI for very long.

Presubmit: https://travis-ci.com/nathanchance/continuous-integration/builds/114812024

[skip ci]

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Author: nathanchance

patches/llvm-all/linux-next

@@ -0,0 +1 @@
+linux

patches/llvm-all/linux/arm64/0001-arm64-Don-t-unconditionally-add-Wno-psabi-to-KBUILD_.patch

@@ -0,0 +1,69 @@
+From c7f5ef329953a798f1a06f87df3cdd38e31879bc Mon Sep 17 00:00:00 2001
+From: Nathan Chancellor <natechancellor@gmail.com>
+Date: Fri, 7 Jun 2019 09:06:38 -0700
+Subject: [PATCH] arm64: Don't unconditionally add -Wno-psabi to KBUILD_CFLAGS
+
+This is a GCC only option, which warns about ABI changes within GCC, so
+unconditionally adding breaks Clang with tons of:
+
+warning: unknown warning option '-Wno-psabi' [-Wunknown-warning-option]
+
+and link time failures:
+
+ld.lld: error: undefined symbol: __efistub___stack_chk_guard
+>>> referenced by arm-stub.c:73
+(/home/nathan/cbl/linux/drivers/firmware/efi/libstub/arm-stub.c:73)
+>>>               arm-stub.stub.o:(__efistub_install_memreserve_table)
+in archive ./drivers/firmware/efi/libstub/lib.a
+
+I suspect the link time failure comes from some flags not being added
+via cc-option, which will always fail when an unknown flag is
+unconditionally added to KBUILD_CFLAGS because -Werror is added after
+commit c3f0d0bc5b01 ("kbuild, LLVMLinux: Add -Werror to cc-option to
+support clang").
+
+$ echo "int main() { return 0; }" | clang -Wno-psabi -o /dev/null -x c -
+warning: unknown warning option '-Wno-psabi' [-Wunknown-warning-option]
+1 warning generated.
+
+$ echo $?
+0
+
+$ echo "int main() { return 0; }" | clang -Werror -Wno-psabi -o /dev/null -x c -
+error: unknown warning option '-Wno-psabi' [-Werror,-Wunknown-warning-option]
+
+$ echo $?
+1
+
+This side effect is user visible (aside from the inordinate amount of
+-Wunknown-warning-option and build failure), as some warnings that are
+normally disabled like -Waddress-of-packed-member or
+-Wunused-const-variable show up.
+
+Use cc-disable-warning so that it gets disabled for GCC and does nothing
+for Clang.
+
+Fixes: ebcc5928c5d9 ("arm64: Silence gcc warnings about arch ABI drift")
+Link: https://github.com/ClangBuiltLinux/linux/issues/511
+Reported-by: Qian Cai <cai@lca.pw>
+Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
+---
+ arch/arm64/Makefile | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
+index 8fbd583b18e1..e9d2e578cbe6 100644
+--- a/arch/arm64/Makefile
++++ b/arch/arm64/Makefile
+@@ -51,7 +51,7 @@ endif
+ 
+ KBUILD_CFLAGS	+= -mgeneral-regs-only $(lseinstr) $(brokengasinst)
+ KBUILD_CFLAGS	+= -fno-asynchronous-unwind-tables
+-KBUILD_CFLAGS	+= -Wno-psabi
++KBUILD_CFLAGS	+= $(call cc-disable-warning, psabi)
+ KBUILD_AFLAGS	+= $(lseinstr) $(brokengasinst)
+ 
+ KBUILD_CFLAGS	+= $(call cc-option,-mabi=lp64)
+-- 
+2.22.0.rc3
+