From: Peter Zijlstra <pet...@infradead.org>

commit 96bc9567cbe112e9320250f01b9c060c882e8619 upstream.

Make issuing a TLB invalidate for page-table pages the normal case.

The reason is twofold:

 - too many invalidates is safer than too few,
 - most architectures use the linux page-tables natively
   and would thus require this.

Make it an opt-out, instead of an opt-in.

No change in behavior intended.

Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Cc: <sta...@vger.kernel.org> # 4.19
Signed-off-by: Santosh Sivaraj <sant...@fossix.org>
[santosh: prerequisite for upcoming tlbflush backports]
---
 arch/Kconfig         | 2 +-
 arch/powerpc/Kconfig | 1 +
 arch/sparc/Kconfig   | 1 +
 arch/x86/Kconfig     | 1 -
 mm/memory.c          | 2 +-
 5 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index a336548487e6..061a12b8140e 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -363,7 +363,7 @@ config HAVE_ARCH_JUMP_LABEL
 config HAVE_RCU_TABLE_FREE
        bool
 
-config HAVE_RCU_TABLE_INVALIDATE
+config HAVE_RCU_TABLE_NO_INVALIDATE
        bool
 
 config ARCH_HAVE_NMI_SAFE_CMPXCHG
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 6f475dc5829b..e09cfb109b8c 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -216,6 +216,7 @@ config PPC
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
        select HAVE_RCU_TABLE_FREE              if SMP
+       select HAVE_RCU_TABLE_NO_INVALIDATE     if HAVE_RCU_TABLE_FREE
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_RELIABLE_STACKTRACE         if PPC64 && CPU_LITTLE_ENDIAN
        select HAVE_SYSCALL_TRACEPOINTS
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index e6f2a38d2e61..d90d632868aa 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -64,6 +64,7 @@ config SPARC64
        select HAVE_KRETPROBES
        select HAVE_KPROBES
        select HAVE_RCU_TABLE_FREE if SMP
+       select HAVE_RCU_TABLE_NO_INVALIDATE if HAVE_RCU_TABLE_FREE
        select HAVE_MEMBLOCK_NODE_MAP
        select HAVE_ARCH_TRANSPARENT_HUGEPAGE
        select HAVE_DYNAMIC_FTRACE
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index af35f5caadbe..181d0d522977 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -181,7 +181,6 @@ config X86
        select HAVE_PERF_REGS
        select HAVE_PERF_USER_STACK_DUMP
        select HAVE_RCU_TABLE_FREE              if PARAVIRT
-       select HAVE_RCU_TABLE_INVALIDATE        if HAVE_RCU_TABLE_FREE
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_RELIABLE_STACKTRACE         if X86_64 && 
(UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
        select HAVE_STACKPROTECTOR              if CC_HAS_SANE_STACKPROTECTOR
diff --git a/mm/memory.c b/mm/memory.c
index 1832c5ed6ac0..ba5689610c04 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -327,7 +327,7 @@ bool __tlb_remove_page_size(struct mmu_gather *tlb, struct 
page *page, int page_
  */
 static inline void tlb_table_invalidate(struct mmu_gather *tlb)
 {
-#ifdef CONFIG_HAVE_RCU_TABLE_INVALIDATE
+#ifndef CONFIG_HAVE_RCU_TABLE_NO_INVALIDATE
        /*
         * Invalidate page-table caches used by hardware walkers. Then we still
         * need to RCU-sched wait while freeing the pages because software
-- 
2.24.1

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