From: Mark Rutland <mark.rutland@arm.com>
Date: Wed, 16 Oct 2019 12:03:04 +0100
Subject: arm64: mm: fix inverted PAR_EL1.F check
Git-commit: 3813733595c0c7c0674d106309b04e871d54dc1c
Patch-mainline: v5.4-rc4
References: jsc#13705,jsc#13695
When detecting a spurious EL1 translation fault, we have the CPU retry
the translation using an AT S1E1R instruction, and inspect PAR_EL1 to
determine if the fault was spurious.
When PAR_EL1.F == 0, the AT instruction successfully translated the
address without a fault, which implies the original fault was spurious.
However, in this case we return false and treat the original fault as if
it was not spurious.
Invert the return value so that we treat such a case as spurious.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 42f91093b043 ("arm64: mm: Ignore spurious translation faults taken from the kernel")
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
arch/arm64/mm/fault.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 855f2a7954e6..9fc6db0bcbad 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -268,8 +268,12 @@ static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
par = read_sysreg(par_el1);
local_irq_restore(flags);
+ /*
+ * If we now have a valid translation, treat the translation fault as
+ * spurious.
+ */
if (!(par & SYS_PAR_EL1_F))
- return false;
+ return true;
/*
* If we got a different type of fault from the AT instruction,
--
2.26.2