[tip:x86/urgent] x86/mm/64: Remove the last VM_BUG_ON() from the TLB code

[tip-bot for Andy Lutomirski]

Commit-ID:  e8b9b0cc8269c85d8167aaee024bfcbb4976c031
Gitweb:     https://git.kernel.org/tip/e8b9b0cc8269c85d8167aaee024bfcbb4976c031
Author:     Andy Lutomirski <luto@xxxxxxxxxx>
AuthorDate: Sat, 14 Oct 2017 09:59:49 -0700
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 18 Oct 2017 15:25:02 +0200

x86/mm/64: Remove the last VM_BUG_ON() from the TLB code

Let's avoid hard-to-diagnose crashes in the future.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
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/f423bbc97864089fbdeb813f1ea126c6eaed844a.1508000261.git.luto@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/mm/tlb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 658bf00..7db23f9 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -147,8 +147,8 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 	this_cpu_write(cpu_tlbstate.is_lazy, false);
 
 	if (real_prev == next) {
-		VM_BUG_ON(this_cpu_read(cpu_tlbstate.ctxs[prev_asid].ctx_id) !=
-			  next->context.ctx_id);
+		VM_WARN_ON(this_cpu_read(cpu_tlbstate.ctxs[prev_asid].ctx_id) !=
+			   next->context.ctx_id);
 
 		/*
 		 * We don't currently support having a real mm loaded without