[PATCH v5 0/6] implement KASLR for powerpc/fsl_booke/64

This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

    KERNELBASE

          64K                     |--> kernel <--|
           |                      |              |
        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
        |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
        |                         |                        1G
        |----->   offset    <-----|

                              kernstart_virt_addr

I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.

Thank you all.

v4->v5:
  Fix "-Werror=maybe-uninitialized" compile error.
  Fix typo "similar as" -> "similar to".
v3->v4:
  Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load and
    __kaslr_offset by symbol instead of magic offsets.
  Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
  Change kaslr-booke32 to kaslr-booke in index.rst
  Switch some instructions to 64-bit.
v2->v3:
  Fix build error when KASLR is disabled.
v1->v2:
  Add __kaslr_offset for the secondary cpu boot up.

Jason Yan (6):
  powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
    kaslr_early_init()
  powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
  powerpc/fsl_booke/64: implement KASLR for fsl_booke64
  powerpc/fsl_booke/64: do not clear the BSS for the second pass
  powerpc/fsl_booke/64: clear the original kernel if randomized
  powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
    and add 64bit part

 Documentation/powerpc/index.rst               |  2 +-
 .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++-
 arch/powerpc/Kconfig                          |  2 +-
 arch/powerpc/kernel/exceptions-64e.S          | 23 +++++
 arch/powerpc/kernel/head_64.S                 | 13 +++
 arch/powerpc/kernel/setup_64.c                |  3 +
 arch/powerpc/mm/mmu_decl.h                    | 23 +++--
 arch/powerpc/mm/nohash/kaslr_booke.c          | 91 +++++++++++++------
 8 files changed, 147 insertions(+), 45 deletions(-)
 rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

-- 
2.17.2

Like the 32bit code, we introduce reloc_kernel_entry() helper to prepare
for the KASLR 64bit version. And move the C declaration of this function
out of CONFIG_PPC32 and use long instead of int for the parameter 'addr'.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
Reviewed-by: Christophe Leroy <redacted>
---
 arch/powerpc/kernel/exceptions-64e.S | 13 +++++++++++++
 arch/powerpc/mm/mmu_decl.h           |  3 ++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index e4076e3c072d..1b9b174bee86 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S

@@ -1679,3 +1679,16 @@ _GLOBAL(setup_ehv_ivors)
 _GLOBAL(setup_lrat_ivor)
 	SET_IVOR(42, 0x340) /* LRAT Error */
 	blr
+
+/*
+ * Return to the start of the relocated kernel and run again
+ * r3 - virtual address of fdt
+ * r4 - entry of the kernel
+ */
+_GLOBAL(reloc_kernel_entry)
+	mfmsr	r7
+	rlwinm	r7, r7, 0, ~(MSR_IS | MSR_DS)
+
+	mtspr	SPRN_SRR0,r4
+	mtspr	SPRN_SRR1,r7
+	rfi

diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 7097e07a209a..605129b5ccdf 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h

@@ -140,9 +140,10 @@ extern void adjust_total_lowmem(void);
 extern int switch_to_as1(void);
 extern void restore_to_as0(int esel, int offset, void *dt_ptr, int bootcpu);
 void create_kaslr_tlb_entry(int entry, unsigned long virt, phys_addr_t phys);
-void reloc_kernel_entry(void *fdt, int addr);
 extern int is_second_reloc;
 #endif
+
+void reloc_kernel_entry(void *fdt, long addr);
 extern void loadcam_entry(unsigned int index);
 extern void loadcam_multi(int first_idx, int num, int tmp_idx);
 

-- 
2.17.2

Some code refactor in kaslr_legal_offset() and kaslr_early_init(). No
functional change. This is a preparation for KASLR fsl_booke64.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
 arch/powerpc/mm/nohash/kaslr_booke.c | 34 +++++++++++++++-------------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 4a75f2d9bf0e..6ebff31fefcc 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c

@@ -25,6 +25,7 @@ struct regions {
 	unsigned long pa_start;
 	unsigned long pa_end;
 	unsigned long kernel_size;
+	unsigned long linear_sz;
 	unsigned long dtb_start;
 	unsigned long dtb_end;
 	unsigned long initrd_start;

@@ -260,11 +261,23 @@ static __init void get_cell_sizes(const void *fdt, int node, int *addr_cells,
 		*size_cells = fdt32_to_cpu(*prop);
 }
 
-static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long index,
-					       unsigned long offset)
+static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long random)
 {
 	unsigned long koffset = 0;
 	unsigned long start;
+	unsigned long index;
+	unsigned long offset;
+
+	/*
+	 * Decide which 64M we want to start
+	 * Only use the low 8 bits of the random seed
+	 */
+	index = random & 0xFF;
+	index %= regions.linear_sz / SZ_64M;
+
+	/* Decide offset inside 64M */
+	offset = random % (SZ_64M - regions.kernel_size);
+	offset = round_down(offset, SZ_16K);
 
 	while ((long)index >= 0) {
 		offset = memstart_addr + index * SZ_64M + offset;

@@ -289,10 +302,9 @@ static inline __init bool kaslr_disabled(void)
 static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size,
 						  unsigned long kernel_sz)
 {
-	unsigned long offset, random;
+	unsigned long random;
 	unsigned long ram, linear_sz;
 	u64 seed;
-	unsigned long index;
 
 	kaslr_get_cmdline(dt_ptr);
 	if (kaslr_disabled())

@@ -333,22 +345,12 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size
 	regions.dtb_start = __pa(dt_ptr);
 	regions.dtb_end = __pa(dt_ptr) + fdt_totalsize(dt_ptr);
 	regions.kernel_size = kernel_sz;
+	regions.linear_sz = linear_sz;
 
 	get_initrd_range(dt_ptr);
 	get_crash_kernel(dt_ptr, ram);
 
-	/*
-	 * Decide which 64M we want to start
-	 * Only use the low 8 bits of the random seed
-	 */
-	index = random & 0xFF;
-	index %= linear_sz / SZ_64M;
-
-	/* Decide offset inside 64M */
-	offset = random % (SZ_64M - kernel_sz);
-	offset = round_down(offset, SZ_16K);
-
-	return kaslr_legal_offset(dt_ptr, index, offset);
+	return kaslr_legal_offset(dt_ptr, random);
 }
 
 /*

-- 
2.17.2

Now we support both 32 and 64 bit KASLR for fsl booke. Add document for
64 bit part and rename kaslr-booke32.rst to kaslr-booke.rst.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
 Documentation/powerpc/index.rst               |  2 +-
 .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++++++++++++---
 2 files changed, 32 insertions(+), 5 deletions(-)
 rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

diff --git a/Documentation/powerpc/index.rst b/Documentation/powerpc/index.rst
index 0d45f0fc8e57..3bad36943b22 100644
--- a/Documentation/powerpc/index.rst
+++ b/Documentation/powerpc/index.rst

@@ -20,7 +20,7 @@ powerpc
     hvcs
     imc
     isa-versions
-    kaslr-booke32
+    kaslr-booke
     mpc52xx
     papr_hcalls
     pci_iov_resource_on_powernv

diff --git a/Documentation/powerpc/kaslr-booke32.rst b/Documentation/powerpc/kaslr-booke.rst
similarity index 59%
rename from Documentation/powerpc/kaslr-booke32.rst
rename to Documentation/powerpc/kaslr-booke.rst
index 8b259fdfdf03..27a862963242 100644
--- a/Documentation/powerpc/kaslr-booke32.rst
+++ b/Documentation/powerpc/kaslr-booke.rst

@@ -1,15 +1,18 @@
 .. SPDX-License-Identifier: GPL-2.0
 
-===========================
-KASLR for Freescale BookE32
-===========================
+=========================
+KASLR for Freescale BookE
+=========================
 
 The word KASLR stands for Kernel Address Space Layout Randomization.
 
 This document tries to explain the implementation of the KASLR for
-Freescale BookE32. KASLR is a security feature that deters exploit
+Freescale BookE. KASLR is a security feature that deters exploit
 attempts relying on knowledge of the location of kernel internals.
 
+KASLR for Freescale BookE32
+-------------------------
+
 Since CONFIG_RELOCATABLE has already supported, what we need to do is
 map or copy kernel to a proper place and relocate. Freescale Book-E
 parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1

@@ -38,5 +41,29 @@ bit of the entropy to decide the index of the 64M zone. Then we chose a
 
                               kernstart_virt_addr
 
+
+KASLR for Freescale BookE64
+---------------------------
+
+The implementation for Freescale BookE64 is similar to BookE32. One
+difference is that Freescale BookE64 set up a TLB mapping of 1G during
+booting. Another difference is that ppc64 needs the kernel to be
+64K-aligned. So we can randomize the kernel in this 1G mapping and make
+it 64K-aligned. This can save some code to creat another TLB map at early
+boot. The disadvantage is that we only have about 1G/64K = 16384 slots to
+put the kernel in::
+
+    KERNELBASE
+
+          64K                     |--> kernel <--|
+           |                      |              |
+        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
+        |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
+        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
+        |                         |                        1G
+        |----->   offset    <-----|
+
+                              kernstart_virt_addr
+
 To enable KASLR, set CONFIG_RANDOMIZE_BASE = y. If KASLR is enable and you
 want to disable it at runtime, add "nokaslr" to the kernel cmdline.

-- 
2.17.2

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

To support secondary cpu boot up, a variable __kaslr_offset was added in
first_256B section. This can help secondary cpu get the kaslr offset
before the 1:1 mapping has been setup.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
 arch/powerpc/Kconfig                 |  2 +-
 arch/powerpc/kernel/exceptions-64e.S | 10 ++++
 arch/powerpc/kernel/head_64.S        |  6 +++
 arch/powerpc/kernel/setup_64.c       |  3 ++
 arch/powerpc/mm/mmu_decl.h           | 20 ++++----
 arch/powerpc/mm/nohash/kaslr_booke.c | 75 +++++++++++++++++++---------
 6 files changed, 83 insertions(+), 33 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 497b7d0b2d7e..0c76601fdd59 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig

@@ -564,7 +564,7 @@ config RELOCATABLE
 
 config RANDOMIZE_BASE
 	bool "Randomize the address of the kernel image"
-	depends on (FSL_BOOKE && FLATMEM && PPC32)
+	depends on (PPC_FSL_BOOK3E && FLATMEM)
 	depends on RELOCATABLE
 	help
 	  Randomizes the virtual address at which the kernel image is

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 1b9b174bee86..260cf1f1e71c 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S

@@ -1378,6 +1378,7 @@ skpinv:	addi	r6,r6,1				/* Increment */
 1:	mflr	r6
 	addi	r6,r6,(2f - 1b)
 	tovirt(r6,r6)
+	add	r6,r6,r19
 	lis	r7,MSR_KERNEL@h
 	ori	r7,r7,MSR_KERNEL@l
 	mtspr	SPRN_SRR0,r6

@@ -1400,6 +1401,7 @@ skpinv:	addi	r6,r6,1				/* Increment */
 
 	/* We translate LR and return */
 	tovirt(r8,r8)
+	add	r8,r8,r19
 	mtlr	r8
 	blr
 

@@ -1528,6 +1530,7 @@ a2_tlbinit_code_end:
  */
 _GLOBAL(start_initialization_book3e)
 	mflr	r28
+	li	r19, 0
 
 	/* First, we need to setup some initial TLBs to map the kernel
 	 * text, data and bss at PAGE_OFFSET. We don't have a real mode

@@ -1570,6 +1573,12 @@ _GLOBAL(book3e_secondary_core_init)
 	cmplwi	r4,0
 	bne	2f
 
+	li	r19, 0
+#ifdef CONFIG_RANDOMIZE_BASE
+	LOAD_REG_ADDR_PIC(r19, __kaslr_offset)
+	ld	r19,0(r19)
+	rlwinm  r19,r19,0,0,5
+#endif
 	/* Setup TLB for this core */
 	bl	initial_tlb_book3e
 

@@ -1602,6 +1611,7 @@ _GLOBAL(book3e_secondary_core_init)
 	lis	r3,PAGE_OFFSET@highest
 	sldi	r3,r3,32
 	or	r28,r28,r3
+	add	r28,r28,r19
 1:	mtlr	r28
 	blr
 

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index ad79fddb974d..454129a3c259 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S

@@ -104,6 +104,12 @@ __secondary_hold_acknowledge:
 	.8byte	0x0
 
 #ifdef CONFIG_RELOCATABLE
+#ifdef CONFIG_RANDOMIZE_BASE
+	.globl	__kaslr_offset
+__kaslr_offset:
+	.8byte	0x0
+#endif
+
 	/* This flag is set to 1 by a loader if the kernel should run
 	 * at the loaded address instead of the linked address.  This
 	 * is used by kexec-tools to keep the the kdump kernel in the

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index e05e6dd67ae6..836e202dfd5b 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c

@@ -67,6 +67,7 @@
 #include <asm/kup.h>
 #include <asm/early_ioremap.h>
 
+#include <mm/mmu_decl.h>
 #include "setup.h"
 
 int spinning_secondaries;

@@ -300,6 +301,8 @@ void __init early_setup(unsigned long dt_ptr)
 	/* Enable early debugging if any specified (see udbg.h) */
 	udbg_early_init();
 
+	kaslr_early_init(__va(dt_ptr), 0);
+
 	udbg_printf(" -> %s(), dt_ptr: 0x%lx\n", __func__, dt_ptr);
 
 	/*

diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 605129b5ccdf..6efbd7fd88a4 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h

@@ -139,22 +139,16 @@ extern unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
 extern void adjust_total_lowmem(void);
 extern int switch_to_as1(void);
 extern void restore_to_as0(int esel, int offset, void *dt_ptr, int bootcpu);
+#endif
 void create_kaslr_tlb_entry(int entry, unsigned long virt, phys_addr_t phys);
 extern int is_second_reloc;
-#endif
+extern unsigned long __kaslr_offset;
+extern unsigned int __run_at_load;
 
 void reloc_kernel_entry(void *fdt, long addr);
 extern void loadcam_entry(unsigned int index);
 extern void loadcam_multi(int first_idx, int num, int tmp_idx);
 
-#ifdef CONFIG_RANDOMIZE_BASE
-void kaslr_early_init(void *dt_ptr, phys_addr_t size);
-void kaslr_late_init(void);
-#else
-static inline void kaslr_early_init(void *dt_ptr, phys_addr_t size) {}
-static inline void kaslr_late_init(void) {}
-#endif
-
 struct tlbcam {
 	u32	MAS0;
 	u32	MAS1;

@@ -164,6 +158,14 @@ struct tlbcam {
 };
 #endif
 
+#ifdef CONFIG_RANDOMIZE_BASE
+void kaslr_early_init(void *dt_ptr, phys_addr_t size);
+void kaslr_late_init(void);
+#else
+static inline void kaslr_early_init(void *dt_ptr, phys_addr_t size) {}
+static inline void kaslr_late_init(void) {}
+#endif
+
 #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_FSL_BOOKE) || defined(CONFIG_PPC_8xx)
 /* 6xx have BATS */
 /* FSL_BOOKE have TLBCAM */

diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 6ebff31fefcc..24ad34641869 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c

@@ -228,10 +228,11 @@ static __init unsigned long get_usable_address(const void *fdt,
 					       unsigned long start,
 					       unsigned long offset)
 {
+	unsigned long unit = IS_ENABLED(CONFIG_PPC32) ? SZ_16K : SZ_64K;
 	unsigned long pa;
 	unsigned long pa_end;
 
-	for (pa = offset; (long)pa > (long)start; pa -= SZ_16K) {
+	for (pa = offset; (long)pa > (long)start; pa -= unit) {
 		pa_end = pa + regions.kernel_size;
 		if (overlaps_region(fdt, pa, pa_end))
 			continue;

@@ -268,24 +269,34 @@ static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long rando
 	unsigned long index;
 	unsigned long offset;
 
-	/*
-	 * Decide which 64M we want to start
-	 * Only use the low 8 bits of the random seed
-	 */
-	index = random & 0xFF;
-	index %= regions.linear_sz / SZ_64M;
-
-	/* Decide offset inside 64M */
-	offset = random % (SZ_64M - regions.kernel_size);
-	offset = round_down(offset, SZ_16K);
+	if (IS_ENABLED(CONFIG_PPC32)) {
+		/*
+		 * Decide which 64M we want to start
+		 * Only use the low 8 bits of the random seed
+		 */
+		index = random & 0xFF;
+		index %= regions.linear_sz / SZ_64M;
+
+		/* Decide offset inside 64M */
+		offset = random % (SZ_64M - regions.kernel_size);
+		offset = round_down(offset, SZ_16K);
+
+		while ((long)index >= 0) {
+			offset = memstart_addr + index * SZ_64M + offset;
+			start = memstart_addr + index * SZ_64M;
+			koffset = get_usable_address(dt_ptr, start, offset);
+			if (koffset)
+				break;
+			index--;
+		}
+	} else {
+		/* Decide kernel offset inside 1G */
+		offset = random % (regions.linear_sz - regions.kernel_size);
+		offset = round_down(offset, SZ_64K);
 
-	while ((long)index >= 0) {
-		offset = memstart_addr + index * SZ_64M + offset;
-		start = memstart_addr + index * SZ_64M;
+		start = memstart_addr;
+		offset = memstart_addr + offset;
 		koffset = get_usable_address(dt_ptr, start, offset);
-		if (koffset)
-			break;
-		index--;
 	}
 
 	if (koffset != 0)

@@ -325,6 +336,7 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size
 	else
 		pr_warn("KASLR: No safe seed for randomizing the kernel base.\n");
 
+#ifdef CONFIG_PPC32
 	ram = min_t(phys_addr_t, __max_low_memory, size);
 	ram = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, true);
 	linear_sz = min_t(unsigned long, ram, SZ_512M);

@@ -332,6 +344,10 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size
 	/* If the linear size is smaller than 64M, do not randmize */
 	if (linear_sz < SZ_64M)
 		return 0;
+#else
+	ram = size;
+	linear_sz = min_t(unsigned long, size, SZ_1G);
+#endif
 
 	/* check for a reserved-memory node and record its cell sizes */
 	regions.reserved_mem = fdt_path_offset(dt_ptr, "/reserved-memory");

@@ -365,6 +381,14 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size)
 	unsigned long offset;
 	unsigned long kernel_sz;
 
+	if (IS_ENABLED(CONFIG_PPC64)) {
+		if (__run_at_load == 1)
+			return;
+
+		/* Get the first memblock size */
+		early_get_first_memblock_info(dt_ptr, &size);
+	}
+
 	kernel_sz = (unsigned long)_end - (unsigned long)_stext;
 
 	offset = kaslr_choose_location(dt_ptr, size, kernel_sz);

@@ -374,14 +398,19 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size)
 	kernstart_virt_addr += offset;
 	kernstart_addr += offset;
 
-	is_second_reloc = 1;
+	if (IS_ENABLED(CONFIG_PPC32)) {
+		is_second_reloc = 1;
 
-	if (offset >= SZ_64M) {
-		tlb_virt = round_down(kernstart_virt_addr, SZ_64M);
-		tlb_phys = round_down(kernstart_addr, SZ_64M);
+		if (offset >= SZ_64M) {
+			tlb_virt = round_down(kernstart_virt_addr, SZ_64M);
+			tlb_phys = round_down(kernstart_addr, SZ_64M);
 
-		/* Create kernel map to relocate in */
-		create_kaslr_tlb_entry(1, tlb_virt, tlb_phys);
+			/* Create kernel map to relocate in */
+			create_kaslr_tlb_entry(1, tlb_virt, tlb_phys);
+		}
+	} else {
+		__kaslr_offset = kernstart_virt_addr - KERNELBASE;
+		__run_at_load = 1;
 	}
 
 	/* Copy the kernel to it's new location and run */

-- 
2.17.2

The BSS section has already cleared out in the first pass. No need to
clear it again. This can save some time when booting with KASLR
enabled.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
 arch/powerpc/kernel/head_64.S | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 454129a3c259..9354c292b709 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S

@@ -913,6 +913,13 @@ start_here_multiplatform:
 	bl      relative_toc
 	tovirt(r2,r2)
 
+	/* Do not clear the BSS for the second pass if randomized */
+	LOAD_REG_ADDR(r3, kernstart_virt_addr)
+	ld	r3,0(r3)
+	LOAD_REG_IMMEDIATE(r4, KERNELBASE)
+	cmpd	r3,r4
+	bne	4f
+
 	/* Clear out the BSS. It may have been done in prom_init,
 	 * already but that's irrelevant since prom_init will soon
 	 * be detached from the kernel completely. Besides, we need

-- 
2.17.2

The original kernel still exists in the memory, clear it now.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
 arch/powerpc/mm/nohash/kaslr_booke.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 24ad34641869..6c46f24cc53d 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c

@@ -382,8 +382,10 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size)
 	unsigned long kernel_sz;
 
 	if (IS_ENABLED(CONFIG_PPC64)) {
-		if (__run_at_load == 1)
+		if (__run_at_load == 1) {
+			kaslr_late_init();
 			return;
+		}
 
 		/* Get the first memblock size */
 		early_get_first_memblock_info(dt_ptr, &size);

-- 
2.17.2

ping...

在 2020/3/30 10:20, Jason Yan 写道:

This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

     KERNELBASE

           64K                     |--> kernel <--|
            |                      |              |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |                         |                        1G
         |----->   offset    <-----|

                               kernstart_virt_addr

I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.

Thank you all.

v4->v5:
   Fix "-Werror=maybe-uninitialized" compile error.
   Fix typo "similar as" -> "similar to".
v3->v4:
   Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load and
     __kaslr_offset by symbol instead of magic offsets.
   Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
   Change kaslr-booke32 to kaslr-booke in index.rst
   Switch some instructions to 64-bit.
v2->v3:
   Fix build error when KASLR is disabled.
v1->v2:
   Add __kaslr_offset for the secondary cpu boot up.

Jason Yan (6):
   powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
     kaslr_early_init()
   powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
   powerpc/fsl_booke/64: implement KASLR for fsl_booke64
   powerpc/fsl_booke/64: do not clear the BSS for the second pass
   powerpc/fsl_booke/64: clear the original kernel if randomized
   powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
     and add 64bit part

  Documentation/powerpc/index.rst               |  2 +-
  .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++-
  arch/powerpc/Kconfig                          |  2 +-
  arch/powerpc/kernel/exceptions-64e.S          | 23 +++++
  arch/powerpc/kernel/head_64.S                 | 13 +++
  arch/powerpc/kernel/setup_64.c                |  3 +
  arch/powerpc/mm/mmu_decl.h                    | 23 +++--
  arch/powerpc/mm/nohash/kaslr_booke.c          | 91 +++++++++++++------
  8 files changed, 147 insertions(+), 45 deletions(-)
  rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

On Mon, 2020-03-30 at 10:20 +0800, Jason Yan wrote:

This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:

https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

    KERNELBASE

          64K                     |--> kernel <--|
           |                      |              |
        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
        |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
        +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
        |                         |                        1G
        |----->   offset    <-----|

                              kernstart_virt_addr

I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.

Thank you all.

v4->v5:
  Fix "-Werror=maybe-uninitialized" compile error.
  Fix typo "similar as" -> "similar to".
v3->v4:
  Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load
and
    __kaslr_offset by symbol instead of magic offsets.
  Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
  Change kaslr-booke32 to kaslr-booke in index.rst
  Switch some instructions to 64-bit.
v2->v3:
  Fix build error when KASLR is disabled.
v1->v2:
  Add __kaslr_offset for the secondary cpu boot up.

Jason Yan (6):
  powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
    kaslr_early_init()
  powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
  powerpc/fsl_booke/64: implement KASLR for fsl_booke64
  powerpc/fsl_booke/64: do not clear the BSS for the second pass
  powerpc/fsl_booke/64: clear the original kernel if randomized
  powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
    and add 64bit part

 Documentation/powerpc/index.rst               |  2 +-
 .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++-
 arch/powerpc/Kconfig                          |  2 +-
 arch/powerpc/kernel/exceptions-64e.S          | 23 +++++
 arch/powerpc/kernel/head_64.S                 | 13 +++
 arch/powerpc/kernel/setup_64.c                |  3 +
 arch/powerpc/mm/mmu_decl.h                    | 23 +++--
 arch/powerpc/mm/nohash/kaslr_booke.c          | 91 +++++++++++++------
 8 files changed, 147 insertions(+), 45 deletions(-)
 rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

Acked-by: Scott Wood <oss@buserror.net>

-Scott

Hi Michael,

What's the status of this series?

Thanks,
Jason

在 2020/3/30 10:20, Jason Yan 写道:

This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

     KERNELBASE

           64K                     |--> kernel <--|
            |                      |              |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |                         |                        1G
         |----->   offset    <-----|

                               kernstart_virt_addr

I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.

Thank you all.

v4->v5:
   Fix "-Werror=maybe-uninitialized" compile error.
   Fix typo "similar as" -> "similar to".
v3->v4:
   Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load and
     __kaslr_offset by symbol instead of magic offsets.
   Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
   Change kaslr-booke32 to kaslr-booke in index.rst
   Switch some instructions to 64-bit.
v2->v3:
   Fix build error when KASLR is disabled.
v1->v2:
   Add __kaslr_offset for the secondary cpu boot up.

Jason Yan (6):
   powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
     kaslr_early_init()
   powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
   powerpc/fsl_booke/64: implement KASLR for fsl_booke64
   powerpc/fsl_booke/64: do not clear the BSS for the second pass
   powerpc/fsl_booke/64: clear the original kernel if randomized
   powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
     and add 64bit part

  Documentation/powerpc/index.rst               |  2 +-
  .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++-
  arch/powerpc/Kconfig                          |  2 +-
  arch/powerpc/kernel/exceptions-64e.S          | 23 +++++
  arch/powerpc/kernel/head_64.S                 | 13 +++
  arch/powerpc/kernel/setup_64.c                |  3 +
  arch/powerpc/mm/mmu_decl.h                    | 23 +++--
  arch/powerpc/mm/nohash/kaslr_booke.c          | 91 +++++++++++++------
  8 files changed, 147 insertions(+), 45 deletions(-)
  rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

Hi Jason,

Apologies for the delay in testing.

I'm seeing this problem when I try to boot on a t4240rdb:

random: get_random_u64 called from .start_kernel+0x734/0x964 with crng_init=0                               [8/973]
clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 0xa9210e89c, max_idle_ns: 440795203878 ns
clocksource: timebase mult[15d17460] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
e6500 family performance monitor hardware support registered
rcu: Hierarchical SRCU implementation.
smp: Bringing up secondary CPUs ...
Processor 2 is stuck.
Processor 3 is stuck.
Processor 4 is stuck.
Processor 5 is stuck.
Processor 6 is stuck.
Processor 7 is stuck.
Processor 8 is stuck.
Processor 9 is stuck.
Processor 10 is stuck.
Processor 11 is stuck.
Processor 12 is stuck.
Processor 13 is stuck.
Processor 14 is stuck.
...
Processor 22 is stuck.                                                                                             
Processor 23 is stuck.                                                            
smp: Brought up 1 node, 2 CPUs                                                                              
Using standard scheduler topology                                                                                  
devtmpfs: initialized                                                                                              
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns                    
futex hash table entries: 8192 (order: 7, 524288 bytes, linear)                                             
NET: Registered protocol family 16                                                                        
audit: initializing netlink subsys (disabled)                                                       
audit: type=2000 audit(108.032:1): state=initialized audit_enabled=0 res=1                                         
Machine: fsl,T4240RDB                                                        
SoC family: QorIQ T4240                                                                   
SoC ID: svr:0x82480020, Revision: 2.0
... boot continues ...


If I boot with nokaslr, all the CPUs come up with no issue.

This is on top of powerpc/merge at
8299da600ad05b8aa0f15ec0f5f03bd40e37d6f0. If you'd like me to test any
debug patches I can do that.

I've attached my .config.

Regards,
Daniel

Hi Daniel,

Thanks for the test. Can you send me the full log which may contain the 
system info such as the following:

-----------------------------------------------------
phys_mem_size     = 0x200000000
dcache_bsize      = 0x20
icache_bsize      = 0x20
cpu_features      = 0x00000003008003b6
   possible        = 0x00000003009003b6
   always          = 0x00000003008003b4
cpu_user_features = 0xdc008000 0x08000000
mmu_features      = 0x000a0010
firmware_features = 0x0000000000000000
physical_start    = 0x20000000
-----------------------------------------------------
barrier-nospec: using isync; sync as speculation barrier
Zone ranges:
   DMA      [mem 0x0000000000000000-0x000000007fffffff]
   Normal   [mem 0x0000000080000000-0x00000001ffffffff]
Movable zone start for each node
Early memory node ranges
   node   0: [mem 0x0000000000000000-0x00000001ffffffff]
Initmem setup node 0 [mem 0x0000000000000000-0x00000001ffffffff]
MMU: Allocated 2112 bytes of context maps for 255 contexts
percpu: Embedded 32 pages/cpu s91736 r0 d39336 u131072
Built 1 zonelists, mobility grouping on.  Total pages: 2064384
Kernel command line: console=ttyS0 root=/dev/ram0
printk: log_buf_len individual max cpu contribution: 16384 bytes
printk: log_buf_len total cpu_extra contributions: 376832 bytes
printk: log_buf_len min size: 131072 bytes
printk: log_buf_len: 524288 bytes
printk: early log buf free: 127460(97%)
Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes, linear)
Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes, linear)
mem auto-init: stack:off, heap alloc:off, heap free:off
Memory: 8135632K/8388608K available (10572K kernel code, 2000K rwdata, 
3396K rodata, 4124K init, 358K bss, 252976K reserved, 0K cma-reserved)
rcu: Hierarchical RCU implementation.
rcu:    RCU event tracing is enabled.
rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
NR_IRQS: 512, nr_irqs: 512, preallocated irqs: 16
mpic: Setting up MPIC " OpenPIC  " version 1.2 at fe0040000, max 24 CPUs
mpic: ISU size: 256, shift: 8, mask: ff
mpic: Initializing for 256 sources
random: get_random_u64 called from .start_kernel+0x724/0x954 with 
crng_init=0
clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 
0x5c4093a7d1, max_idle_ns: 440795210635 ns
clocksource: timebase mult[2800000] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
e6500 family performance monitor hardware support registered
rcu: Hierarchical SRCU implementation.
smp: Bringing up secondary CPUs ...
smp: Brought up 1 node, 24 CPUs



在 2020/4/25 1:17, Daniel Axtens 写道:

Hi Jason,

Apologies for the delay in testing.

I'm seeing this problem when I try to boot on a t4240rdb:

random: get_random_u64 called from .start_kernel+0x734/0x964 with crng_init=0                               [8/973]
clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 0xa9210e89c, max_idle_ns: 440795203878 ns
clocksource: timebase mult[15d17460] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
e6500 family performance monitor hardware support registered
rcu: Hierarchical SRCU implementation.
smp: Bringing up secondary CPUs ...
Processor 2 is stuck.
Processor 3 is stuck.
Processor 4 is stuck.
Processor 5 is stuck.
Processor 6 is stuck.
Processor 7 is stuck.
Processor 8 is stuck.
Processor 9 is stuck.
Processor 10 is stuck.
Processor 11 is stuck.
Processor 12 is stuck.
Processor 13 is stuck.
Processor 14 is stuck.
...
Processor 22 is stuck.
Processor 23 is stuck.
smp: Brought up 1 node, 2 CPUs
Using standard scheduler topology
devtmpfs: initialized
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
futex hash table entries: 8192 (order: 7, 524288 bytes, linear)
NET: Registered protocol family 16
audit: initializing netlink subsys (disabled)
audit: type=2000 audit(108.032:1): state=initialized audit_enabled=0 res=1
Machine: fsl,T4240RDB
SoC family: QorIQ T4240
SoC ID: svr:0x82480020, Revision: 2.0
... boot continues ...


If I boot with nokaslr, all the CPUs come up with no issue.

This is on top of powerpc/merge at
8299da600ad05b8aa0f15ec0f5f03bd40e37d6f0. If you'd like me to test any
debug patches I can do that.

I've attached my .config.

Regards,
Daniel

quoted

This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*

The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.

     KERNELBASE

           64K                     |--> kernel <--|
            |                      |              |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |  |  |  |....|  |  |  |  |  |  |  |  |  |....|  |  |
         +--+--+--+    +--+--+--+--+--+--+--+--+--+    +--+--+
         |                         |                        1G
         |----->   offset    <-----|

                               kernstart_virt_addr

I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.

Thank you all.

v4->v5:
   Fix "-Werror=maybe-uninitialized" compile error.
   Fix typo "similar as" -> "similar to".
v3->v4:
   Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load and
     __kaslr_offset by symbol instead of magic offsets.
   Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
   Change kaslr-booke32 to kaslr-booke in index.rst
   Switch some instructions to 64-bit.
v2->v3:
   Fix build error when KASLR is disabled.
v1->v2:
   Add __kaslr_offset for the secondary cpu boot up.

Jason Yan (6):
   powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
     kaslr_early_init()
   powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
   powerpc/fsl_booke/64: implement KASLR for fsl_booke64
   powerpc/fsl_booke/64: do not clear the BSS for the second pass
   powerpc/fsl_booke/64: clear the original kernel if randomized
   powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
     and add 64bit part

  Documentation/powerpc/index.rst               |  2 +-
  .../{kaslr-booke32.rst => kaslr-booke.rst}    | 35 ++++++-
  arch/powerpc/Kconfig                          |  2 +-
  arch/powerpc/kernel/exceptions-64e.S          | 23 +++++
  arch/powerpc/kernel/head_64.S                 | 13 +++
  arch/powerpc/kernel/setup_64.c                |  3 +
  arch/powerpc/mm/mmu_decl.h                    | 23 +++--
  arch/powerpc/mm/nohash/kaslr_booke.c          | 91 +++++++++++++------
  8 files changed, 147 insertions(+), 45 deletions(-)
  rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)

-- 
2.17.2

Hi Jason,

Thanks for the test. Can you send me the full log which may contain the 
system info such as the following:

It's attached.

Regards,
Daniel