um: Fix kcov crash during startup

Kcov fails to start when compiled with kcov. Disable KCOV on
arch/uml/kernel/skas.

  $ gdb -q -ex r ./vmlinux
  Program received signal SIGSEGV, Segmentation fault.
  check_kcov_mode (t=<>, needed_mode=<>) at kernel/kcov.c:70
  70		mode = READ_ONCE(t->kcov_mode);

Signed-off-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/arch/um/kernel/skas/Makefile b/arch/um/kernel/skas/Makefile
index 0b76d8869c945da564818570194a50557a142ec3..5bd3edfcfedfda9dbbc6ab86f622142b6533ecb4 100644 (file)
--- a/arch/um/kernel/skas/Makefile
+++ b/arch/um/kernel/skas/Makefile
@@ -12,4 +12,6 @@ obj-y := clone.o mmu.o process.o syscall.o uaccess.o
 CFLAGS_clone.o := $(CFLAGS_NO_HARDENING)
 UNPROFILE_OBJS := clone.o
 
+KCOV_INSTRUMENT := n
+
 include arch/um/scripts/Makefile.rules