Subject: [PATCH 24/25] arm64:ilp32: add vdso-ilp32 and use for signal return

From: [email-masked] (Zhangjian (Bamvor))
Date: Tue, 3 May 2016 20:41:25 +0800

Hi, all

On 2016/5/3 19:07, Zhangjian (Bamvor) wrote:
>
>
> On 2016/5/3 17:05, Arnd Bergmann wrote:
>> On Tuesday 03 May 2016 10:00:45 Catalin Marinas wrote:
>>> On Fri, Apr 29, 2016 at 07:30:19PM +0200, Arnd Bergmann wrote:
>>>> On Friday 29 April 2016 17:01:55 Catalin Marinas wrote:
>>>>> On Wed, Apr 06, 2016 at 01:08:46AM +0300, Yury Norov wrote:
>>>>>> ILP32 VDSO exports next symbols:
>>>>>>   __kernel_rt_sigreturn;
>>>>>>   __kernel_gettimeofday;
>>>>>>   __kernel_clock_gettime;
>>>>>>   __kernel_clock_getres;
>>>>>
>>>>> [...]
>>>>>
>>>>>> +$(obj)/gettimeofday-ilp32.o: $(src)/../vdso/gettimeofday.S
>>>>>> + $(call if_changed_dep,vdso-ilp32as)
>>>>>
>>>>> Are struct timeval and timespec the same between ILP32 and LP64? For
>>>>> example, __kernel_gettimeofday() assumes TVAL_TV_SEC offset defined in
>>>>> asm-offsets.c based on the LP64 timeval.
>>>>
>>>> No, ilp32 uses the generic 32-bit data structures, which have a 32-bit
>>>> time_t. I guess that means it can work for little-endian but not
>>>> big-endian, right?
>>>
>>> I don't think it works for little-endian either. The LP64 struct timeval
>>> is 16 bytes while the ILP32 one is 8 bytes. The VDSO gettimeofday is
>>> storing 16 bytes (stp x10, x11, [x0, #TVAL_TV_SEC])
>>
>> You are right. Yury asked pointed out the same thing on IRC as well.
>> Using the 64-bit gettimeofday() will put the right number in the
>> .tv_sec member on little-endian, but will write zeroes to tv_nsec
>> and corrupt the memory following it.
>>
>> Yury also tried it out and noticed that for a (so far) unknown reason,
>> the vdso gets never used by his glibc build, so it has not triggered
>> any test case failures.
> We found this issue too. And it is because the version is different from
> the glibc wanted. We define 2.6.39 for lp64 but 2.6 for ilp32 in vdso
> in kernel:
> +VERSION
> +{
> +    LINUX_2.6 {
> +    global:
> +        __kernel_rt_sigreturn;
> +        __kernel_gettimeofday;
> +        __kernel_clock_gettime;
> +        __kernel_clock_getres;
> +    local: *;
> +    };
> +}
> If I change 2.6 to 2.6.39, the ilp32 application will call vdso instead
> of syscall. But the result is wrong as Catalin mentioned before.
>
> Should we set this version to 4.6 or higher version? We will need to update
> the version in "sysdeps/unix/sysv/linux/aarch64/init-first.c" too:
> static inline void
> _libc_vdso_platform_setup (void)
> {
>    PREPARE_VERSION (linux2639, "LINUX_2.6.39", 123718537);
>
>    void *p = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2639);
>    PTR_MANGLE (p);
>    VDSO_SYMBOL(gettimeofday) = p;
>
>    p = _dl_vdso_vsym ("__kernel_clock_gettime", &linux2639);
>    PTR_MANGLE (p);
>    VDSO_SYMBOL(clock_gettime) = p;
>
>    p = _dl_vdso_vsym ("__kernel_clock_getres", &linux2639);
>    PTR_MANGLE (p);
>    VDSO_SYMBOL(clock_getres) = p;
> }

After apply this patch with my small testcase, the vsyscall of gettimeofday in
ilp32 works in both big endian and small endian. In this patch, I use the
different register and offset for ilp32 and lp64. Actually, the
COMPAT_TVAL_TV_SEC is same as TVAL_TV_SEC(so as to COMPAT_TSPEC_TV_SEC and
TSPEC_TV_SEC). I add it to keep the logic clear. I also change the version
of vdso to 4.6. It should change to 2.6.39 if glibc is not update.

diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 574081f..c8e32eb 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -101,6 +101,11 @@ int main(void)
    DEFINE(TSPEC_TV_SEC,		offsetof(struct timespec, tv_sec));
    DEFINE(TSPEC_TV_NSEC,		offsetof(struct timespec, tv_nsec));
    BLANK();
+  DEFINE(COMPAT_TVAL_TV_SEC,	offsetof(struct compat_timeval, tv_sec));
+  DEFINE(COMPAT_TVAL_TV_USEC,	offsetof(struct compat_timeval, tv_usec));
+  DEFINE(COMPAT_TSPEC_TV_SEC,	offsetof(struct compat_timespec, tv_sec));
+  DEFINE(COMPAT_TSPEC_TV_NSEC,	offsetof(struct compat_timespec, tv_nsec));
+  BLANK();
    DEFINE(TZ_MINWEST,		offsetof(struct timezone, tz_minuteswest));
    DEFINE(TZ_DSTTIME,		offsetof(struct timezone, tz_dsttime));
    BLANK();
diff --git a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
index ddc63fd..d182a8d 100644
--- a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
+++ b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
@@ -79,7 +79,7 @@ PHDRS
   */
  VERSION
  {
-	LINUX_2.6 {
+	LINUX_4.6 {
  	global:
  		__kernel_rt_sigreturn;
  		__kernel_gettimeofday;
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
index efa79e8..4551f55 100644
--- a/arch/arm64/kernel/vdso/gettimeofday.S
+++ b/arch/arm64/kernel/vdso/gettimeofday.S
@@ -25,6 +25,14 @@
  #define NSEC_PER_SEC_LO16	0xca00
  #define NSEC_PER_SEC_HI16	0x3b9a

+#ifdef __LP64__
+#define PTR_REG(n)      x##n
+#define OFFSET(n)	n
+#else
+#define PTR_REG(n)      w##n
+#define OFFSET(n)	COMPAT_##n
+#endif
+
  vdso_data	.req	x6
  use_syscall	.req	w7
  seqcnt		.req	w8
@@ -68,7 +76,7 @@ ENTRY(__kernel_gettimeofday)
  	mov	x13, #1000
  	lsl	x13, x13, x12
  	udiv	x11, x11, x13
-	stp	x10, x11, [x0, #TVAL_TV_SEC]
+	stp	PTR_REG(10), PTR_REG(11), [x0, #OFFSET(TVAL_TV_SEC)]
  2:
  	/* If tz is NULL, return 0. */
  	cbz	x1, 3f
@@ -159,7 +167,7 @@ ENTRY(__kernel_clock_gettime)

  6:	/* Store to the user timespec. */
  	lsr	x11, x11, x12
-	stp	x10, x11, [x1, #TSPEC_TV_SEC]
+	stp	PTR_REG(10), PTR_REG(11), [x1, #OFFSET(TSPEC_TV_SEC)]
  	mov	x0, xzr
  	ret
  7:
-- 
1.8.4.5

I am not sure if I should merge above patch into original one. If I
merge it with another patch I send in 13, April, The overall patch is
as follows. I could resend the following patch to this thread if
needed:

 From b0a74395cbf18643f3f5b410be425df85d8d68d1 Mon Sep 17 00:00:00 2001
From: Philipp Tomsich <[email-masked]>
Date: Wed, 6 Apr 2016 01:08:46 +0300
Subject: [PATCH] arm64:ilp32: add vdso-ilp32 and use for signal return

ILP32 VDSO exports next symbols:
  __kernel_rt_sigreturn;
  __kernel_gettimeofday;
  __kernel_clock_gettime;
  __kernel_clock_getres;

What shared object to use, kernel selects depending on result of
is_ilp32_compat_task() in arch/arm64/kernel/vdso.c, so it substitutes
correct pages and spec.

Adjusted to move the move data page before code pages in sync with
commit 601255ae3c98fdeeee3a8bb4696425e4f868b4f1

Care must be taken when we update time to user space for ilp32.
Because the size of time struct(timeval, timespec) is different from
lp64.

Signed-off-by: Philipp Tomsich <[email-masked]>
Signed-off-by: Christoph Muellner <[email-masked]>
Signed-off-by: Yury Norov <[email-masked]>
Signed-off-by: Bamvor Jian Zhang <[email-masked]>
---
  arch/arm64/include/asm/vdso.h                 |  6 ++
  arch/arm64/kernel/Makefile                    |  7 ++
  arch/arm64/kernel/asm-offsets.c               |  5 ++
  arch/arm64/kernel/signal.c                    |  2 +
  arch/arm64/kernel/vdso-ilp32/.gitignore       |  2 +
  arch/arm64/kernel/vdso-ilp32/Makefile         | 72 ++++++++++++++++++++
  arch/arm64/kernel/vdso-ilp32/vdso-ilp32.S     | 33 ++++++++++
  arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S | 95 +++++++++++++++++++++++++++
  arch/arm64/kernel/vdso.c                      | 61 ++++++++++++++---
  arch/arm64/kernel/vdso/gettimeofday.S         | 12 +++-
  10 files changed, 283 insertions(+), 12 deletions(-)
  create mode 100644 arch/arm64/kernel/vdso-ilp32/.gitignore
  create mode 100644 arch/arm64/kernel/vdso-ilp32/Makefile
  create mode 100644 arch/arm64/kernel/vdso-ilp32/vdso-ilp32.S
  create mode 100644 arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S

diff --git a/arch/arm64/include/asm/vdso.h b/arch/arm64/include/asm/vdso.h
index 839ce00..649a9a4 100644
--- a/arch/arm64/include/asm/vdso.h
+++ b/arch/arm64/include/asm/vdso.h
@@ -29,6 +29,12 @@

  #include <generated/vdso-offsets.h>

+#ifdef CONFIG_ARM64_ILP32
+#include <generated/vdso-ilp32-offsets.h>
+#else
+#define vdso_offset_sigtramp_ilp32
+#endif
+
  #define VDSO_SYMBOL(base, name)						   \
  ({									   \
  	(void *)(vdso_offset_##name - VDSO_LBASE + (unsigned long)(base)); \
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 09e4373..0f27a10 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -50,6 +50,7 @@ arm64-obj-$(CONFIG_PARAVIRT)		+= paravirt.o
  arm64-obj-$(CONFIG_RANDOMIZE_BASE)	+= kaslr.o

  obj-y					+= $(arm64-obj-y) vdso/
+obj-$(CONFIG_ARM64_ILP32)		+= vdso-ilp32/
  obj-m					+= $(arm64-obj-m)
  head-y					:= head.o
  extra-y					+= $(head-y) vmlinux.lds
@@ -57,3 +58,9 @@ extra-y					+= $(head-y) vmlinux.lds
  # vDSO - this must be built first to generate the symbol offsets
  $(call objectify,$(arm64-obj-y)): $(obj)/vdso/vdso-offsets.h
  $(obj)/vdso/vdso-offsets.h: $(obj)/vdso
+
+# vDSO - this must be built first to generate the symbol offsets
+ifeq ($(CONFIG_ARM64_ILP32),y)
+$(call objectify,$(arm64-obj-y)): $(obj)/vdso-ilp32/vdso-ilp32-offsets.h
+$(obj)/vdso-ilp32/vdso-ilp32-offsets.h: $(obj)/vdso-ilp32
+endif
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index e229525..e5db887 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -101,6 +101,11 @@ int main(void)
    DEFINE(TSPEC_TV_SEC,		offsetof(struct timespec, tv_sec));
    DEFINE(TSPEC_TV_NSEC,		offsetof(struct timespec, tv_nsec));
    BLANK();
+  DEFINE(COMPAT_TVAL_TV_SEC,	offsetof(struct compat_timeval, tv_sec));
+  DEFINE(COMPAT_TVAL_TV_USEC,	offsetof(struct compat_timeval, tv_usec));
+  DEFINE(COMPAT_TSPEC_TV_SEC,	offsetof(struct compat_timespec, tv_sec));
+  DEFINE(COMPAT_TSPEC_TV_NSEC,	offsetof(struct compat_timespec, tv_nsec));
+  BLANK();
    DEFINE(TZ_MINWEST,		offsetof(struct timezone, tz_minuteswest));
    DEFINE(TZ_DSTTIME,		offsetof(struct timezone, tz_dsttime));
    BLANK();
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 45bcd96..933cdcf 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -264,6 +264,8 @@ void setup_return(struct pt_regs *regs, struct k_sigaction *ka,

  	if (ka->sa.sa_flags & SA_RESTORER)
  		sigtramp = ka->sa.sa_restorer;
+	else if (is_ilp32_compat_task())
+		sigtramp = VDSO_SYMBOL(current->mm->context.vdso, sigtramp_ilp32);
  	else
  		sigtramp = VDSO_SYMBOL(current->mm->context.vdso, sigtramp);

diff --git a/arch/arm64/kernel/vdso-ilp32/.gitignore b/arch/arm64/kernel/vdso-ilp32/.gitignore
new file mode 100644
index 0000000..61806c3
--- /dev/null
+++ b/arch/arm64/kernel/vdso-ilp32/.gitignore
@@ -0,0 +1,2 @@
+vdso-ilp32.lds
+vdso-ilp32-offsets.h
diff --git a/arch/arm64/kernel/vdso-ilp32/Makefile b/arch/arm64/kernel/vdso-ilp32/Makefile
new file mode 100644
index 0000000..c8f5472
--- /dev/null
+++ b/arch/arm64/kernel/vdso-ilp32/Makefile
@@ -0,0 +1,72 @@
+#
+# Building a vDSO image for AArch64.
+#
+# Author: Will Deacon <[email-masked]>
+# Heavily based on the vDSO Makefiles for other archs.
+#
+
+obj-ilp32-vdso := gettimeofday-ilp32.o note-ilp32.o sigreturn-ilp32.o
+
+# Build rules
+targets := $(obj-ilp32-vdso) vdso-ilp32.so vdso-ilp32.so.dbg
+obj-ilp32-vdso := $(addprefix $(obj)/, $(obj-ilp32-vdso))
+
+ccflags-y := -shared -fno-common -fno-builtin
+ccflags-y += -nostdlib -Wl,-soname=linux-ilp32-vdso.so.1 \
+		$(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
+
+obj-y += vdso-ilp32.o
+extra-y += vdso-ilp32.lds vdso-ilp32-offsets.h
+CPPFLAGS_vdso-ilp32.lds += -P -C -U$(ARCH) -mabi=ilp32
+
+# Force dependency (incbin is bad)
+$(obj)/vdso-ilp32.o : $(obj)/vdso-ilp32.so
+
+# Link rule for the .so file, .lds has to be first
+$(obj)/vdso-ilp32.so.dbg: $(src)/vdso-ilp32.lds $(obj-ilp32-vdso)
+	$(call if_changed,vdso-ilp32ld)
+
+# Strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+# Generate VDSO offsets using helper script
+gen-vdsosym := $(srctree)/$(src)/../vdso/gen_vdso_offsets.sh
+quiet_cmd_vdsosym = VDSOSYM $@
+define cmd_vdsosym
+	$(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ && \
+	cp $@ include/generated/
+endef
+
+$(obj)/vdso-ilp32-offsets.h: $(obj)/vdso-ilp32.so.dbg FORCE
+	$(call if_changed,vdsosym)
+
+# Assembly rules for the .S files
+#$(obj-ilp32-vdso): %.o: $(src)/../vdso/$(subst -ilp32,,%.S)
+#	$(call if_changed_dep,vdso-ilp32as)
+
+$(obj)/gettimeofday-ilp32.o: $(src)/../vdso/gettimeofday.S
+	$(call if_changed_dep,vdso-ilp32as)
+
+$(obj)/note-ilp32.o: $(src)/../vdso/note.S
+	$(call if_changed_dep,vdso-ilp32as)
+
+$(obj)/sigreturn-ilp32.o: $(src)/../vdso/sigreturn.S
+	$(call if_changed_dep,vdso-ilp32as)
+
+# Actual build commands
+quiet_cmd_vdso-ilp32ld = VDSOILP32L $@
+      cmd_vdso-ilp32ld = $(CC) $(c_flags) -mabi=ilp32  -Wl,-n -Wl,-T $^ -o $@
+quiet_cmd_vdso-ilp32as = VDSOILP32A $@
+      cmd_vdso-ilp32as = $(CC) $(a_flags) -mabi=ilp32 -c -o $@ $<
+
+# Install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso-ilp32.so: $(obj)/vdso-ilp32.so.dbg
+	@mkdir -p $(MODLIB)/vdso
+	$(call cmd,vdso_install)
+
+vdso_install: vdso-ilp32.so
diff --git a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.S b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.S
new file mode 100644
index 0000000..46ac072
--- /dev/null
+++ b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.S
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2012 ARM Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Will Deacon <[email-masked]>
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/const.h>
+#include <asm/page.h>
+
+	__PAGE_ALIGNED_DATA
+
+	.globl vdso_ilp32_start, vdso_ilp32_end
+	.balign PAGE_SIZE
+vdso_ilp32_start:
+	.incbin "arch/arm64/kernel/vdso-ilp32/vdso-ilp32.so"
+	.balign PAGE_SIZE
+vdso_ilp32_end:
+
+	.previous
diff --git a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
new file mode 100644
index 0000000..d182a8d
--- /dev/null
+++ b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
@@ -0,0 +1,95 @@
+/*
+ * GNU linker script for the VDSO library.
+ *
+ * Copyright (C) 2012 ARM Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Will Deacon <[email-masked]>
+ * Heavily based on the vDSO linker scripts for other archs.
+ */
+
+#include <linux/const.h>
+#include <asm/page.h>

+#include <asm/vdso.h>
+
+SECTIONS
+{
+	PROVIDE(_vdso_data = . - PAGE_SIZE);
+	. = VDSO_LBASE + SIZEOF_HEADERS;
+
+	.hash		: { *(.hash) }			:text
+	.gnu.hash	: { *(.gnu.hash) }
+	.dynsym		: { *(.dynsym) }
+	.dynstr		: { *(.dynstr) }
+	.gnu.version	: { *(.gnu.version) }
+	.gnu.version_d	: { *(.gnu.version_d) }
+	.gnu.version_r	: { *(.gnu.version_r) }
+
+	.note		: { *(.note.*) }		:text	:note
+
+	. = ALIGN(16);
+
+	.text		: { *(.text*) }			:text	=0xd503201f
+	PROVIDE (__etext = .);
+	PROVIDE (_etext = .);
+	PROVIDE (etext = .);
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
+	.rodata		: { *(.rodata*) }		:text
+
+	_end = .;
+	PROVIDE(end = .);
+
+	/DISCARD/	: {
+		*(.note.GNU-stack)
+		*(.data .data.* .gnu.linkonce.d.* .sdata*)
+		*(.bss .sbss .dynbss .dynsbss)
+	}
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+	text		PT_LOAD		FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+	dynamic		PT_DYNAMIC	FLAGS(4);		/* PF_R */
+	note		PT_NOTE		FLAGS(4);		/* PF_R */
+	eh_frame_hdr	PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+	LINUX_4.6 {
+	global:
+		__kernel_rt_sigreturn;
+		__kernel_gettimeofday;
+		__kernel_clock_gettime;
+		__kernel_clock_getres;
+	local: *;
+	};
+}
+
+/*
+ * Make the sigreturn code visible to the kernel.
+ */
+VDSO_sigtramp_ilp32		= __kernel_rt_sigreturn;
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 26352a6..521a8e4 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -40,6 +40,12 @@ extern char vdso_start, vdso_end;
  static unsigned long vdso_pages;
  static struct page **vdso_pagelist;

+#ifdef CONFIG_ARM64_ILP32
+extern char vdso_ilp32_start, vdso_ilp32_end;
+static unsigned long vdso_ilp32_pages;
+static struct page **vdso_ilp32_pagelist;
+#endif
+
  /*
   * The vDSO data page.
   */
@@ -109,24 +115,29 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
  }
  #endif /* CONFIG_AARCH32_EL0 */

-static struct vm_special_mapping vdso_spec[2];
-
-static int __init vdso_init(void)
+static int __init vdso_init_common(char *vdso_start, char *vdso_end,
+					  unsigned long *vdso_pagesp,
+					  struct page ***vdso_pagelistp,
+					  struct vm_special_mapping* vdso_spec)
  {
  	int i;
+	unsigned long vdso_pages;
+	struct page **vdso_pagelist;

-	if (memcmp(&vdso_start, "\177ELF", 4)) {
+	if (memcmp(vdso_start, "\177ELF", 4)) {
  		pr_err("vDSO is not a valid ELF object!\n");
  		return -EINVAL;
  	}

-	vdso_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT;
+	vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
+	*vdso_pagesp = vdso_pages;
  	pr_info("vdso: %ld pages (%ld code @ %p, %ld data @ %p)\n",
-		vdso_pages + 1, vdso_pages, &vdso_start, 1L, vdso_data);
+		vdso_pages + 1, vdso_pages, vdso_start, 1L, vdso_data);

  	/* Allocate the vDSO pagelist, plus a page for the data. */
  	vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *),
  				GFP_KERNEL);
+	*vdso_pagelistp = vdso_pagelist;
  	if (vdso_pagelist == NULL)
  		return -ENOMEM;

@@ -135,7 +146,7 @@ static int __init vdso_init(void)

  	/* Grab the vDSO code pages. */
  	for (i = 0; i < vdso_pages; i++)
-		vdso_pagelist[i + 1] = virt_to_page(&vdso_start + i * PAGE_SIZE);
+		vdso_pagelist[i + 1] = virt_to_page(vdso_start + i * PAGE_SIZE);

  	/* Populate the special mapping structures */
  	vdso_spec[0] = (struct vm_special_mapping) {
@@ -150,16 +161,46 @@ static int __init vdso_init(void)

  	return 0;
  }
+
+static struct vm_special_mapping vdso_spec[2];
+
+static int __init vdso_init(void)
+{
+	return vdso_init_common(&vdso_start, &vdso_end,
+				&vdso_pages, &vdso_pagelist,
+				vdso_spec);
+}
  arch_initcall(vdso_init);

+#ifdef CONFIG_ARM64_ILP32
+static struct vm_special_mapping vdso_ilp32_spec[2];
+
+static int __init vdso_ilp32_init(void)
+{
+	return vdso_init_common(&vdso_ilp32_start, &vdso_ilp32_end,
+				&vdso_ilp32_pages, &vdso_ilp32_pagelist,
+				vdso_ilp32_spec);
+}
+arch_initcall(vdso_ilp32_init);
+#endif
+
  int arch_setup_additional_pages(struct linux_binprm *bprm,
  				int uses_interp)
  {
  	struct mm_struct *mm = current->mm;
  	unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
  	void *ret;
+	unsigned long pages = vdso_pages;
+	struct vm_special_mapping *spec = vdso_spec;
+
+#ifdef CONFIG_ARM64_ILP32
+	if (is_ilp32_compat_task()) {
+	        pages = vdso_ilp32_pages;
+	        spec = vdso_ilp32_spec;
+	}
+#endif

-	vdso_text_len = vdso_pages << PAGE_SHIFT;
+	vdso_text_len = pages << PAGE_SHIFT;
  	/* Be sure to map the data page */
  	vdso_mapping_len = vdso_text_len + PAGE_SIZE;

@@ -171,7 +212,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
  	}
  	ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE,
  				       VM_READ|VM_MAYREAD,
-				       &vdso_spec[0]);
+				       &spec[0]);
  	if (IS_ERR(ret))
  		goto up_fail;

@@ -180,7 +221,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
  	ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
  				       VM_READ|VM_EXEC|
  				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
-				       &vdso_spec[1]);
+				       &spec[1]);
  	if (IS_ERR(ret))
  		goto up_fail;

diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
index efa79e8..4551f55 100644
--- a/arch/arm64/kernel/vdso/gettimeofday.S
+++ b/arch/arm64/kernel/vdso/gettimeofday.S
@@ -25,6 +25,14 @@
  #define NSEC_PER_SEC_LO16	0xca00
  #define NSEC_PER_SEC_HI16	0x3b9a

+#ifdef __LP64__
+#define PTR_REG(n)      x##n
+#define OFFSET(n)	n
+#else
+#define PTR_REG(n)      w##n
+#define OFFSET(n)	COMPAT_##n
+#endif
+
  vdso_data	.req	x6
  use_syscall	.req	w7
  seqcnt		.req	w8
@@ -68,7 +76,7 @@ ENTRY(__kernel_gettimeofday)
  	mov	x13, #1000
  	lsl	x13, x13, x12
  	udiv	x11, x11, x13
-	stp	x10, x11, [x0, #TVAL_TV_SEC]
+	stp	PTR_REG(10), PTR_REG(11), [x0, #OFFSET(TVAL_TV_SEC)]
  2:
  	/* If tz is NULL, return 0. */
  	cbz	x1, 3f
@@ -159,7 +167,7 @@ ENTRY(__kernel_clock_gettime)

  6:	/* Store to the user timespec. */
  	lsr	x11, x11, x12
-	stp	x10, x11, [x1, #TSPEC_TV_SEC]
+	stp	PTR_REG(10), PTR_REG(11), [x1, #OFFSET(TSPEC_TV_SEC)]
  	mov	x0, xzr
  	ret
  7:
-- 
1.8.4.5

Regads

Bamvor
> Regards
> Bamvor
>>     Arnd