diff mbox series

vdso: Improve cmd_vdso_check to check all dynamic relocations

Message ID 20220830193701.1702962-1-maskray@google.com (mailing list archive)
State Handled Elsewhere
Headers show
Series vdso: Improve cmd_vdso_check to check all dynamic relocations | expand

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Commit Message

Fangrui Song Aug. 30, 2022, 7:37 p.m. UTC
The actual intention is that no dynamic relocation exists. However, some
GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
relocations. E.g. powerpc64le ld as of 2.38 has the issue with
defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
ignore them.

With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
not called "absolute relocations". (The patch is motivated by the arm64
port missing R_AARCH64_RELATIVE.)

While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
grep 3.7.

Signed-off-by: Fangrui Song <maskray@google.com>
---
 arch/arm/vdso/Makefile            |  3 ---
 arch/arm64/kernel/vdso/Makefile   |  3 ---
 arch/arm64/kernel/vdso32/Makefile |  3 ---
 arch/csky/kernel/vdso/Makefile    |  3 ---
 arch/loongarch/vdso/Makefile      |  3 ---
 arch/mips/vdso/Makefile           |  3 ---
 arch/powerpc/kernel/vdso/Makefile |  1 -
 arch/riscv/kernel/vdso/Makefile   |  3 ---
 arch/s390/kernel/vdso32/Makefile  |  2 --
 arch/s390/kernel/vdso64/Makefile  |  2 --
 arch/x86/entry/vdso/Makefile      |  4 ----
 lib/vdso/Makefile                 | 13 ++++---------
 12 files changed, 4 insertions(+), 39 deletions(-)

Comments

Fangrui Song Sept. 10, 2022, 7:53 a.m. UTC | #1
On 2022-08-30, Fangrui Song wrote:
>The actual intention is that no dynamic relocation exists. However, some
>GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
>determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
>relocations. E.g. powerpc64le ld as of 2.38 has the issue with
>defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
>ignore them.
>
>With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
>bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
>not called "absolute relocations". (The patch is motivated by the arm64
>port missing R_AARCH64_RELATIVE.)
>
>While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
>grep 3.7.
>
>Signed-off-by: Fangrui Song <maskray@google.com>
>---
>[...]
>

Ping.
Fangrui Song Sept. 28, 2022, 5:25 a.m. UTC | #2
On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
>
> On 2022-08-30, Fangrui Song wrote:
> >The actual intention is that no dynamic relocation exists. However, some
> >GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
> >determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
> >relocations. E.g. powerpc64le ld as of 2.38 has the issue with
> >defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
> >ignore them.
> >
> >With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
> >bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
> >not called "absolute relocations". (The patch is motivated by the arm64
> >port missing R_AARCH64_RELATIVE.)
> >
> >While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
> >grep 3.7.
> >
> >Signed-off-by: Fangrui Song <maskray@google.com>
> >---
> >[...]
> >
>
> Ping.

Ping^2 :)
Christophe Leroy Nov. 14, 2022, 12:31 p.m. UTC | #3
Le 28/09/2022 à 07:25, Fangrui Song a écrit :
> On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
>>
>> On 2022-08-30, Fangrui Song wrote:
>>> The actual intention is that no dynamic relocation exists. However, some
>>> GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
>>> determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
>>> relocations. E.g. powerpc64le ld as of 2.38 has the issue with
>>> defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
>>> ignore them.
>>>
>>> With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
>>> bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
>>> not called "absolute relocations". (The patch is motivated by the arm64
>>> port missing R_AARCH64_RELATIVE.)
>>>
>>> While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
>>> grep 3.7.
>>>
>>> Signed-off-by: Fangrui Song <maskray@google.com>
>>> ---
>>> [...]
>>>
>>
>> Ping.
> 
> Ping^2 :)

Can you explain which ARCH_REL_TYPE_ABS can be removed with this change ?
How is the verification done if ARCH_REL_TYPE_ABS is removed ?
Fangrui Song Nov. 15, 2022, 12:46 a.m. UTC | #4
On 2022-11-14, Christophe Leroy wrote:
>
>
>Le 28/09/2022 à 07:25, Fangrui Song a écrit :
>> On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
>>>
>>> On 2022-08-30, Fangrui Song wrote:
>>>> The actual intention is that no dynamic relocation exists. However, some
>>>> GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
>>>> determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
>>>> relocations. E.g. powerpc64le ld as of 2.38 has the issue with
>>>> defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
>>>> ignore them.
>>>>
>>>> With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
>>>> bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
>>>> not called "absolute relocations". (The patch is motivated by the arm64
>>>> port missing R_AARCH64_RELATIVE.)
>>>>
>>>> While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
>>>> grep 3.7.
>>>>
>>>> Signed-off-by: Fangrui Song <maskray@google.com>
>>>> ---
>>>> [...]
>>>>
>>>
>>> Ping.
>>
>> Ping^2 :)
>
>Can you explain which ARCH_REL_TYPE_ABS can be removed with this change ?
>How is the verification done if ARCH_REL_TYPE_ABS is removed ?

All ARCH_REL_TYPE_ABS relocation types can be removed. As explained, the
real intention is to check no dynamic relocation, and this is done by
the new

   cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q "R_\w*_"; \

in this patch.

grep -v _NONE is to work around some GNU ld ports (and likely older releases
of some ports even if their latest versions are fixed) which produce
unneeded R_*_NONE dynamic relocations.
Fangrui Song Dec. 4, 2022, 4:50 a.m. UTC | #5
On Mon, Nov 14, 2022 at 4:46 PM Fangrui Song <maskray@google.com> wrote:
>
> On 2022-11-14, Christophe Leroy wrote:
> >
> >
> >Le 28/09/2022 à 07:25, Fangrui Song a écrit :
> >> On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
> >>>
> >>> On 2022-08-30, Fangrui Song wrote:
> >>>> The actual intention is that no dynamic relocation exists. However, some
> >>>> GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
> >>>> determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
> >>>> relocations. E.g. powerpc64le ld as of 2.38 has the issue with
> >>>> defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
> >>>> ignore them.
> >>>>
> >>>> With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
> >>>> bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
> >>>> not called "absolute relocations". (The patch is motivated by the arm64
> >>>> port missing R_AARCH64_RELATIVE.)
> >>>>
> >>>> While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
> >>>> grep 3.7.
> >>>>
> >>>> Signed-off-by: Fangrui Song <maskray@google.com>
> >>>> ---
> >>>> [...]
> >>>>
> >>>
> >>> Ping.
> >>
> >> Ping^2 :)
> >
> >Can you explain which ARCH_REL_TYPE_ABS can be removed with this change ?
> >How is the verification done if ARCH_REL_TYPE_ABS is removed ?
>
> All ARCH_REL_TYPE_ABS relocation types can be removed. As explained, the
> real intention is to check no dynamic relocation, and this is done by
> the new
>
>    cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q "R_\w*_"; \
>
> in this patch.
>
> grep -v _NONE is to work around some GNU ld ports (and likely older releases
> of some ports even if their latest versions are fixed) which produce
> unneeded R_*_NONE dynamic relocations.

Ping :)
Christophe Leroy Dec. 4, 2022, 4:58 p.m. UTC | #6
Le 04/12/2022 à 05:50, Fangrui Song a écrit :
> On Mon, Nov 14, 2022 at 4:46 PM Fangrui Song <maskray@google.com> wrote:
>>
>> On 2022-11-14, Christophe Leroy wrote:
>>>
>>>
>>> Le 28/09/2022 à 07:25, Fangrui Song a écrit :
>>>> On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
>>>>>
>>>>> On 2022-08-30, Fangrui Song wrote:
>>>>>> The actual intention is that no dynamic relocation exists. However, some
>>>>>> GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
>>>>>> determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
>>>>>> relocations. E.g. powerpc64le ld as of 2.38 has the issue with
>>>>>> defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
>>>>>> ignore them.
>>>>>>
>>>>>> With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
>>>>>> bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
>>>>>> not called "absolute relocations". (The patch is motivated by the arm64
>>>>>> port missing R_AARCH64_RELATIVE.)
>>>>>>
>>>>>> While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
>>>>>> grep 3.7.
>>>>>>
>>>>>> Signed-off-by: Fangrui Song <maskray@google.com>
>>>>>> ---
>>>>>> [...]
>>>>>>
>>>>>
>>>>> Ping.
>>>>
>>>> Ping^2 :)
>>>
>>> Can you explain which ARCH_REL_TYPE_ABS can be removed with this change ?
>>> How is the verification done if ARCH_REL_TYPE_ABS is removed ?
>>
>> All ARCH_REL_TYPE_ABS relocation types can be removed. As explained, the
>> real intention is to check no dynamic relocation, and this is done by
>> the new

Well, there was a typo in my question, I wanted to ask 'why', not 'which'.

>>
>>     cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q "R_\w*_"; \
>>
>> in this patch.
>>
>> grep -v _NONE is to work around some GNU ld ports (and likely older releases
>> of some ports even if their latest versions are fixed) which produce
>> unneeded R_*_NONE dynamic relocations.
> 
> Ping :)

Ok, that seems to work on powerpc.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Fangrui Song Dec. 18, 2022, 6:31 p.m. UTC | #7
On Sun, Dec 4, 2022 at 8:58 AM Christophe Leroy
<christophe.leroy@csgroup.eu> wrote:
>
>
>
> Le 04/12/2022 à 05:50, Fangrui Song a écrit :
> > On Mon, Nov 14, 2022 at 4:46 PM Fangrui Song <maskray@google.com> wrote:
> >>
> >> On 2022-11-14, Christophe Leroy wrote:
> >>>
> >>>
> >>> Le 28/09/2022 à 07:25, Fangrui Song a écrit :
> >>>> On Sat, Sep 10, 2022 at 12:53 AM Fangrui Song <maskray@google.com> wrote:
> >>>>>
> >>>>> On 2022-08-30, Fangrui Song wrote:
> >>>>>> The actual intention is that no dynamic relocation exists. However, some
> >>>>>> GNU ld ports produce unneeded R_*_NONE. (If a port is not care enough to
> >>>>>> determine the exact .rel[a].dyn size, the trailing zeros become R_*_NONE
> >>>>>> relocations. E.g. powerpc64le ld as of 2.38 has the issue with
> >>>>>> defconfig.) R_*_NONE are generally no-op in the dynamic loaders. So just
> >>>>>> ignore them.
> >>>>>>
> >>>>>> With the change, we can remove ARCH_REL_TYPE_ABS. ARCH_REL_TYPE_ABS is a
> >>>>>> bit misnomer as ports may check RELAVETIVE/GLOB_DAT/JUMP_SLOT which are
> >>>>>> not called "absolute relocations". (The patch is motivated by the arm64
> >>>>>> port missing R_AARCH64_RELATIVE.)
> >>>>>>
> >>>>>> While here, replace "egrep" with "grep" as "egrep" is deprecated in GNU
> >>>>>> grep 3.7.
> >>>>>>
> >>>>>> Signed-off-by: Fangrui Song <maskray@google.com>
> >>>>>> ---
> >>>>>> [...]
> >>>>>>
> >>>>>
> >>>>> Ping.
> >>>>
> >>>> Ping^2 :)
> >>>
> >>> Can you explain which ARCH_REL_TYPE_ABS can be removed with this change ?
> >>> How is the verification done if ARCH_REL_TYPE_ABS is removed ?
> >>
> >> All ARCH_REL_TYPE_ABS relocation types can be removed. As explained, the
> >> real intention is to check no dynamic relocation, and this is done by
> >> the new
>
> Well, there was a typo in my question, I wanted to ask 'why', not 'which'.
>
> >>
> >>     cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q "R_\w*_"; \
> >>
> >> in this patch.
> >>
> >> grep -v _NONE is to work around some GNU ld ports (and likely older releases
> >> of some ports even if their latest versions are fixed) which produce
> >> unneeded R_*_NONE dynamic relocations.
> >
> > Ping :)
>
> Ok, that seems to work on powerpc.
>
> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

Thanks. Can a maintainer pick up this commit?
diff mbox series

Patch

diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
index 8ca1c9f262a2..5ebd2e6f7d46 100644
--- a/arch/arm/vdso/Makefile
+++ b/arch/arm/vdso/Makefile
@@ -1,8 +1,5 @@ 
 # SPDX-License-Identifier: GPL-2.0
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_ARM_JUMP_SLOT|R_ARM_GLOB_DAT|R_ARM_ABS32
 include $(srctree)/lib/vdso/Makefile
 
 hostprogs := vdsomunge
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index bafbf78fab77..66dc4f338a86 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -6,9 +6,6 @@ 
 # Heavily based on the vDSO Makefiles for other archs.
 #
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_AARCH64_JUMP_SLOT|R_AARCH64_GLOB_DAT|R_AARCH64_ABS64
 include $(srctree)/lib/vdso/Makefile
 
 obj-vdso := vgettimeofday.o note.o sigreturn.o
diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile
index 36c8f66cad25..48d713d59ef2 100644
--- a/arch/arm64/kernel/vdso32/Makefile
+++ b/arch/arm64/kernel/vdso32/Makefile
@@ -3,9 +3,6 @@ 
 # Makefile for vdso32
 #
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_ARM_JUMP_SLOT|R_ARM_GLOB_DAT|R_ARM_ABS32
 include $(srctree)/lib/vdso/Makefile
 
 # Same as cc-*option, but using CC_COMPAT instead of CC
diff --git a/arch/csky/kernel/vdso/Makefile b/arch/csky/kernel/vdso/Makefile
index 0b6909f10667..86c8c4de1b0f 100644
--- a/arch/csky/kernel/vdso/Makefile
+++ b/arch/csky/kernel/vdso/Makefile
@@ -1,8 +1,5 @@ 
 # SPDX-License-Identifier: GPL-2.0-only
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_CKCORE_ADDR32|R_CKCORE_JUMP_SLOT
 include $(srctree)/lib/vdso/Makefile
 
 # Symbols present in the vdso
diff --git a/arch/loongarch/vdso/Makefile b/arch/loongarch/vdso/Makefile
index d89e2ac75f7b..1b2e0f149f55 100644
--- a/arch/loongarch/vdso/Makefile
+++ b/arch/loongarch/vdso/Makefile
@@ -1,9 +1,6 @@ 
 # SPDX-License-Identifier: GPL-2.0
 # Objects to go into the VDSO.
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_LARCH_32|R_LARCH_64|R_LARCH_MARK_LA|R_LARCH_JUMP_SLOT
 include $(srctree)/lib/vdso/Makefile
 
 obj-vdso-y := elf.o vgetcpu.o vgettimeofday.o sigreturn.o
diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
index f72658b3a53f..cea97abffc03 100644
--- a/arch/mips/vdso/Makefile
+++ b/arch/mips/vdso/Makefile
@@ -4,9 +4,6 @@ 
 # Sanitizer runtimes are unavailable and cannot be linked here.
  KCSAN_SANITIZE			:= n
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT
 include $(srctree)/lib/vdso/Makefile
 
 obj-vdso-y := elf.o vgettimeofday.o sigreturn.o
diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile
index 096b0bf1335f..d3c5be32034d 100644
--- a/arch/powerpc/kernel/vdso/Makefile
+++ b/arch/powerpc/kernel/vdso/Makefile
@@ -2,7 +2,6 @@ 
 
 # List of files in the vdso, has to be asm only for now
 
-ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN|R_PPC_REL24
 include $(srctree)/lib/vdso/Makefile
 
 obj-vdso32 = sigtramp32-32.o gettimeofday-32.o datapage-32.o cacheflush-32.o note-32.o getcpu-32.o
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index f2e065671e4d..77d6bed3a700 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -1,9 +1,6 @@ 
 # SPDX-License-Identifier: GPL-2.0-only
 # Copied from arch/tile/kernel/vdso/Makefile
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_RISCV_32|R_RISCV_64|R_RISCV_JUMP_SLOT
 include $(srctree)/lib/vdso/Makefile
 # Symbols present in the vdso
 vdso-syms  = rt_sigreturn
diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
index 245bddfe9bc0..e795fdbbf484 100644
--- a/arch/s390/kernel/vdso32/Makefile
+++ b/arch/s390/kernel/vdso32/Makefile
@@ -2,8 +2,6 @@ 
 # List of files in the vdso
 
 KCOV_INSTRUMENT := n
-ARCH_REL_TYPE_ABS := R_390_COPY|R_390_GLOB_DAT|R_390_JMP_SLOT|R_390_RELATIVE
-ARCH_REL_TYPE_ABS += R_390_GOT|R_390_PLT
 
 include $(srctree)/lib/vdso/Makefile
 obj-vdso32 = vdso_user_wrapper-32.o note-32.o
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
index 9e2b95a222a9..47dbbfdfad68 100644
--- a/arch/s390/kernel/vdso64/Makefile
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -2,8 +2,6 @@ 
 # List of files in the vdso
 
 KCOV_INSTRUMENT := n
-ARCH_REL_TYPE_ABS := R_390_COPY|R_390_GLOB_DAT|R_390_JMP_SLOT|R_390_RELATIVE
-ARCH_REL_TYPE_ABS += R_390_GOT|R_390_PLT
 
 include $(srctree)/lib/vdso/Makefile
 obj-vdso64 = vdso_user_wrapper.o note.o
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 12f6c4d714cd..a97f3630ca20 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -3,10 +3,6 @@ 
 # Building vDSO images for x86.
 #
 
-# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
-# the inclusion of generic Makefile.
-ARCH_REL_TYPE_ABS := R_X86_64_JUMP_SLOT|R_X86_64_GLOB_DAT|R_X86_64_RELATIVE|
-ARCH_REL_TYPE_ABS += R_386_GLOB_DAT|R_386_JMP_SLOT|R_386_RELATIVE
 include $(srctree)/lib/vdso/Makefile
 
 # Sanitizer runtimes are unavailable and cannot be linked here.
diff --git a/lib/vdso/Makefile b/lib/vdso/Makefile
index c415a685d61b..9f031eafc465 100644
--- a/lib/vdso/Makefile
+++ b/lib/vdso/Makefile
@@ -5,18 +5,13 @@  GENERIC_VDSO_DIR := $(dir $(GENERIC_VDSO_MK_PATH))
 
 c-gettimeofday-$(CONFIG_GENERIC_GETTIMEOFDAY) := $(addprefix $(GENERIC_VDSO_DIR), gettimeofday.c)
 
-# This cmd checks that the vdso library does not contain absolute relocation
+# This cmd checks that the vdso library does not contain dynamic relocations.
 # It has to be called after the linking of the vdso library and requires it
 # as a parameter.
 #
-# $(ARCH_REL_TYPE_ABS) is defined in the arch specific makefile and corresponds
-# to the absolute relocation types printed by "objdump -R" and accepted by the
-# dynamic linker.
-ifndef ARCH_REL_TYPE_ABS
-$(error ARCH_REL_TYPE_ABS is not set)
-endif
-
+# As a workaround for some GNU ld ports which produce unneeded R_*_NONE
+# dynamic relocations, ignore R_*_NONE.
 quiet_cmd_vdso_check = VDSOCHK $@
-      cmd_vdso_check = if $(OBJDUMP) -R $@ | egrep -h "$(ARCH_REL_TYPE_ABS)"; \
+      cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q " R_\w*_"; \
 		       then (echo >&2 "$@: dynamic relocations are not supported"; \
 			     rm -f $@; /bin/false); fi