Patch "arm64: mm: Use non-global mappings for kernel space" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    arm64: mm: Use non-global mappings for kernel space

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-mm-use-non-global-mappings-for-kernel-space.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Apr  5 21:39:27 CEST 2018
From: Mark Rutland <mark.rutland@arm.com>
Date: Tue,  3 Apr 2018 12:08:57 +0100
Subject: arm64: mm: Use non-global mappings for kernel space
To: stable@vger.kernel.org
Cc: mark.brown@linaro.org, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, will.deacon@arm.com
Message-ID: <20180403110923.43575-2-mark.rutland@arm.com>

From: Will Deacon <will.deacon@arm.com>

commit e046eb0c9bf2 upstream.

In preparation for unmapping the kernel whilst running in userspace,
make the kernel mappings non-global so we can avoid expensive TLB
invalidation on kernel exit to userspace.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Tested-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alex Shi <alex.shi@linaro.org> [v4.9 backport]
Signed-off-by: Mark Rutland <mark.rutland@arm.com> [v4.9 backport]
Tested-by: Will Deacon <will.deacon@arm.com>
Tested-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/kernel-pgtable.h |   12 ++++++++++--
 arch/arm64/include/asm/pgtable-prot.h   |   21 +++++++++++++++------
 2 files changed, 25 insertions(+), 8 deletions(-)

--- a/arch/arm64/include/asm/kernel-pgtable.h
+++ b/arch/arm64/include/asm/kernel-pgtable.h
@@ -71,8 +71,16 @@
 /*
  * Initial memory map attributes.
  */
-#define SWAPPER_PTE_FLAGS	(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
-#define SWAPPER_PMD_FLAGS	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+#define _SWAPPER_PTE_FLAGS	(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
+#define _SWAPPER_PMD_FLAGS	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+#define SWAPPER_PTE_FLAGS	(_SWAPPER_PTE_FLAGS | PTE_NG)
+#define SWAPPER_PMD_FLAGS	(_SWAPPER_PMD_FLAGS | PMD_SECT_NG)
+#else
+#define SWAPPER_PTE_FLAGS	_SWAPPER_PTE_FLAGS
+#define SWAPPER_PMD_FLAGS	_SWAPPER_PMD_FLAGS
+#endif
 
 #if ARM64_SWAPPER_USES_SECTION_MAPS
 #define SWAPPER_MM_MMUFLAGS	(PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS)
--- a/arch/arm64/include/asm/pgtable-prot.h
+++ b/arch/arm64/include/asm/pgtable-prot.h
@@ -34,8 +34,16 @@
 
 #include <asm/pgtable-types.h>
 
-#define PROT_DEFAULT		(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
-#define PROT_SECT_DEFAULT	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+#define _PROT_DEFAULT		(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
+#define _PROT_SECT_DEFAULT	(PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+#define PROT_DEFAULT		(_PROT_DEFAULT | PTE_NG)
+#define PROT_SECT_DEFAULT	(_PROT_SECT_DEFAULT | PMD_SECT_NG)
+#else
+#define PROT_DEFAULT		_PROT_DEFAULT
+#define PROT_SECT_DEFAULT	_PROT_SECT_DEFAULT
+#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
 
 #define PROT_DEVICE_nGnRnE	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
 #define PROT_DEVICE_nGnRE	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE))
@@ -48,6 +56,7 @@
 #define PROT_SECT_NORMAL_EXEC	(PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
 
 #define _PAGE_DEFAULT		(PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
+#define _HYP_PAGE_DEFAULT	(_PAGE_DEFAULT & ~PTE_NG)
 
 #define PAGE_KERNEL		__pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE)
 #define PAGE_KERNEL_RO		__pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_RDONLY)
@@ -55,15 +64,15 @@
 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE)
 #define PAGE_KERNEL_EXEC_CONT	__pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_CONT)
 
-#define PAGE_HYP		__pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_HYP_XN)
-#define PAGE_HYP_EXEC		__pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY)
-#define PAGE_HYP_RO		__pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN)
+#define PAGE_HYP		__pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_HYP_XN)
+#define PAGE_HYP_EXEC		__pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY)
+#define PAGE_HYP_RO		__pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN)
 #define PAGE_HYP_DEVICE		__pgprot(PROT_DEVICE_nGnRE | PTE_HYP)
 
 #define PAGE_S2			__pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_NORMAL) | PTE_S2_RDONLY)
 #define PAGE_S2_DEVICE		__pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_DEVICE_nGnRE) | PTE_S2_RDONLY | PTE_UXN)
 
-#define PAGE_NONE		__pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_PXN | PTE_UXN)
+#define PAGE_NONE		__pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_NG | PTE_PXN | PTE_UXN)
 #define PAGE_SHARED		__pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
 #define PAGE_SHARED_EXEC	__pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_WRITE)
 #define PAGE_COPY		__pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)


Patches currently in stable-queue which might be from mark.rutland@arm.com are

queue-4.9/arm64-mm-add-arm64_kernel_unmapped_at_el0-helper.patch
queue-4.9/arm64-entry-reword-comment-about-post_ttbr_update_workaround.patch
queue-4.9/arm64-kaslr-put-kernel-vectors-address-in-separate-data-page.patch
queue-4.9/arm64-turn-on-kpti-only-on-cpus-that-need-it.patch
queue-4.9/arm64-force-kpti-to-be-disabled-on-cavium-thunderx.patch
queue-4.9/arm64-mm-allocate-asids-in-pairs.patch
queue-4.9/arm64-tls-avoid-unconditional-zeroing-of-tpidrro_el0-for-native-tasks.patch
queue-4.9/arm64-use-ret-instruction-for-exiting-the-trampoline.patch
queue-4.9/arm64-entry-explicitly-pass-exception-level-to-kernel_ventry-macro.patch
queue-4.9/arm64-kpti-make-use-of-ng-dependent-on-arm64_kernel_unmapped_at_el0.patch
queue-4.9/arm64-mm-use-non-global-mappings-for-kernel-space.patch
queue-4.9/arm64-capabilities-handle-duplicate-entries-for-a-capability.patch
queue-4.9/arm64-entry-hook-up-entry-trampoline-to-exception-vectors.patch
queue-4.9/arm64-mm-invalidate-both-kernel-and-user-asids-when-performing-tlbi.patch
queue-4.9/arm64-mm-map-entry-trampoline-into-trampoline-and-kernel-page-tables.patch
queue-4.9/module-extend-rodata-off-boot-cmdline-parameter-to-module-mappings.patch
queue-4.9/arm64-kconfig-reword-unmap_kernel_at_el0-kconfig-entry.patch
queue-4.9/arm64-mm-move-asid-from-ttbr0-to-ttbr1.patch
queue-4.9/arm64-allow-checking-of-a-cpu-local-erratum.patch
queue-4.9/arm64-take-into-account-id_aa64pfr0_el1.csv3.patch
queue-4.9/arm64-kconfig-add-config_unmap_kernel_at_el0.patch
queue-4.9/arm64-idmap-use-awx-flags-for-.idmap.text-.pushsection-directives.patch
queue-4.9/arm64-factor-out-entry-stack-manipulation.patch
queue-4.9/arm64-entry-add-exception-trampoline-page-for-exceptions-from-el0.patch
queue-4.9/arm64-kpti-add-enable-callback-to-remap-swapper-using-ng-mappings.patch
queue-4.9/arm64-entry-add-fake-cpu-feature-for-unmapping-the-kernel-at-el0.patch
queue-4.9/arm64-cputype-add-midr-values-for-cavium-thunderx2-cpus.patch