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From: Kristina Martsenko <kristina.martsenko@arm.com>
Date: Fri, 9 Jun 2017 16:35:53 +0100
Subject: arm64: mm: don't print out page table entries on EL0 faults
Git-commit: bf396c09c2447a787d02af34cf167e953f85fa42
Patch-mainline: v4.13-rc1
References: fate#326419

When we take a fault from EL0 that can't be handled, we print out the
page table entries associated with the faulting address. This allows
userspace to print out any current page table entries, including kernel
(TTBR1) entries. Exposing kernel mappings like this could pose a
security risk, so don't print out page table information on EL0 faults.
(But still print it out for EL1 faults.) This also follows the same
behaviour as x86, printing out page table entries on kernel mode faults
but not user mode faults.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---
 arch/arm64/mm/fault.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 9d27b1720c52..b5a1605398b7 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -264,7 +264,6 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
 		pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n",
 			tsk->comm, task_pid_nr(tsk), inf->name, sig,
 			addr, esr);
-		show_pte(addr);
 		__show_regs(regs);
 	}
 
-- 
2.19.1