[PATCH 4.4 10/78] x86/mm: Build arch/x86/mm/tlb.c even on !SMP

From: Greg Kroah-Hartman
Date: Fri Dec 22 2017 - 05:52:32 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Andy Lutomirski <luto@xxxxxxxxxx>

commit e1074888c326038340a1ada9129d679e661f2ea6 upstream.

Currently all of the functions that live in tlb.c are inlined on
!SMP builds. One can debate whether this is a good idea (in many
respects the code in tlb.c is better than the inlined UP code).

Regardless, I want to add code that needs to be built on UP and SMP
kernels and relates to tlb flushing, so arrange for tlb.c to be
compiled unconditionally.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
Reviewed-by: Borislav Petkov <bp@xxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/f0d778f0d828fc46e5d1946bca80f0aaf9abf032.1461688545.git.luto@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
arch/x86/mm/Makefile | 3 +--
arch/x86/mm/tlb.c | 4 ++++
2 files changed, 5 insertions(+), 2 deletions(-)

--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,5 +1,5 @@
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
+ pat.o pgtable.o physaddr.o gup.o setup_nx.o tlb.o

# Make sure __phys_addr has no stackprotector
nostackp := $(call cc-option, -fno-stack-protector)
@@ -9,7 +9,6 @@ CFLAGS_setup_nx.o := $(nostackp)
CFLAGS_fault.o := -I$(src)/../include/asm/trace

obj-$(CONFIG_X86_PAT) += pat_rbtree.o
-obj-$(CONFIG_SMP) += tlb.o

obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o

--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -28,6 +28,8 @@
* Implement flush IPI by CALL_FUNCTION_VECTOR, Alex Shi
*/

+#ifdef CONFIG_SMP
+
struct flush_tlb_info {
struct mm_struct *flush_mm;
unsigned long flush_start;
@@ -351,3 +353,5 @@ static int __init create_tlb_single_page
return 0;
}
late_initcall(create_tlb_single_page_flush_ceiling);
+
+#endif /* CONFIG_SMP */