From: Andi Kleen <ak@linux.intel.com>
Date: Tue, 7 Aug 2018 22:09:36 +0000 (-0700)
Subject: x86/speculation/l1tf: Invert all not present mappings
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a5f284feeb2071f4a381fccf1c8c9b3e05b7a465;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

x86/speculation/l1tf: Invert all not present mappings

commit f22cc87f6c1f771b57c407555cfefd811cdd9507 upstream

For kernel mappings PAGE_PROTNONE is not necessarily set for a non present
mapping, but the inversion logic explicitely checks for !PRESENT and
PROT_NONE.

Remove the PROT_NONE check and make the inversion unconditional for all not
present mappings.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/x86/include/asm/pgtable-invert.h b/arch/x86/include/asm/pgtable-invert.h
index 177564187fc0..44b1203ece12 100644
--- a/arch/x86/include/asm/pgtable-invert.h
+++ b/arch/x86/include/asm/pgtable-invert.h
@@ -6,7 +6,7 @@
 
 static inline bool __pte_needs_invert(u64 val)
 {
-	return (val & (_PAGE_PRESENT|_PAGE_PROTNONE)) == _PAGE_PROTNONE;
+	return !(val & _PAGE_PRESENT);
 }
 
 /* Get a mask to xor with the page table entry to get the correct pfn. */