From: Tom Lendacky <thomas.lendacky@amd.com>
Date: Tue, 10 Oct 2017 14:45:04 -0500
Subject: x86/mm: Disable various instrumentations of mm/mem_encrypt.c and
mm/tlb.c
Git-commit: 67bb8e999e0aeac285d22f0e53c856b9df5282c6
Patch-mainline: v4.14-rc5
References: fate#322123
Some routines in mem_encrypt.c are called very early in the boot process,
e.g. sme_enable(). When CONFIG_KCOV=y is defined the resulting code added
to sme_enable() (and others) for KCOV instrumentation results in a kernel
crash. Disable the KCOV instrumentation for mem_encrypt.c by adding
KCOV_INSTRUMENT_mem_encrypt.o := n to arch/x86/mm/Makefile.
In order to avoid other possible early boot issues, model mem_encrypt.c
after head64.c in regards to tools. In addition to disabling KCOV as
stated above and a previous patch that disables branch profiling, also
remove the "-pg" CFLAG if CONFIG_FUNCTION_TRACER is enabled and set
KASAN_SANITIZE to "n", each of which are done on a file basis.
Reported-by: kernel test robot <lkp@01.org>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171010194504.18887.38053.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/mm/Makefile | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,5 +1,12 @@
-# Kernel does not boot with instrumentation of tlb.c.
-KCOV_INSTRUMENT_tlb.o := n
+# Kernel does not boot with instrumentation of tlb.c and mem_encrypt.c
+KCOV_INSTRUMENT_tlb.o := n
+KCOV_INSTRUMENT_mem_encrypt.o := n
+
+KASAN_SANITIZE_mem_encrypt.o := n
+
+ifdef CONFIG_FUNCTION_TRACER
+CFLAGS_REMOVE_mem_encrypt.o = -pg
+endif
obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
pat.o pgtable.o physaddr.o gup.o setup_nx.o tlb.o