arch/tile: avoid generating .eh_frame information in modules

The tile tool chain uses the .eh_frame information for backtracing.
The vmlinux build drops any .eh_frame sections at link time, but when
present in kernel modules, it causes a module load failure due to the
presence of unsupported pc-relative relocations. When compiling to
use compiler feedback support, the compiler by default omits .eh_frame
information, so we don't see this problem. But when not using feedback,
we need to explicitly suppress the .eh_frame.

Signed-off-by: Chris Metcalf <[e-mail]>
Cc: [e-mail]

arch/tile/Makefile

···
   endif
 endif
 
+# The tile compiler may emit .eh_frame information for backtracing.
+# In kernel modules, this causes load failures due to unsupported relocations.
+KBUILD_CFLAGS   += -fno-asynchronous-unwind-tables
+
 ifneq ($(CONFIG_DEBUG_EXTRA_FLAGS),"")
 KBUILD_CFLAGS   += $(CONFIG_DEBUG_EXTRA_FLAGS)
 endif