* Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4
@ 2020-08-16 12:14 Sedat Dilek
2020-08-26 12:11 ` Sedat Dilek
0 siblings, 1 reply; 4+ messages in thread
From: Sedat Dilek @ 2020-08-16 12:14 UTC (permalink / raw)
To: Masahiro Yamada; +Cc: linux-kbuild
Hi Masahiro,
I wondered why my generated linux-image-db Debian packages were so big
when I use GCC toolchain instead of LLVM toolchain.
It turned out I mixed both...
KBUILD_AFLAGS += -Wa,-gdwarf-2
...together with...
DEBUG_CFLAGS += -gdwarf-4
...when CONFIG_DEBUG_INFO_DWARF4=y is set.
So I hacked up something like the following to prevent this:
diff --git a/Makefile b/Makefile
index 24a4c1b97bb0..e7a8e47b0e34 100644
--- a/Makefile
+++ b/Makefile
@@ -815,7 +815,11 @@ DEBUG_CFLAGS += -gsplit-dwarf
else
DEBUG_CFLAGS += -g
endif
+ifdef CONFIG_DEBUG_INFO_AS_DWARF2
KBUILD_AFLAGS += -Wa,-gdwarf-2
+else ifdef CONFIG_DEBUG_INFO_AS_DWARF4
+KBUILD_AFLAGS += -Wa,-gdwarf-4
+endif
endif
ifdef CONFIG_DEBUG_INFO_DWARF4
DEBUG_CFLAGS += -gdwarf-4
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 9ad9210d70a1..9f11fc71462c 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -257,10 +257,23 @@ config DEBUG_INFO_SPLIT
to know about the .dwo files and include them.
Incompatible with older versions of ccache.
+config DEBUG_INFO_AS_DWARF2
+ bool "Use DWARF-2 assembler option with debuginfo"
+ depends on $(cc-option,-Wa$(comma)-gdwarf-2)
+ help
+ Set DWARF-2 assembler option with debuginfo
+
+config DEBUG_INFO_AS_DWARF4
+ bool "Use DWARF-4 assembler option with debuginfo"
+ depends on $(cc-option,-Wa$(comma)-gdwarf-4)
+ help
+ Set DWARF-4 assembler option with debuginfo
+
config DEBUG_INFO_DWARF4
bool "Generate dwarf4 debuginfo"
depends on DEBUG_INFO
depends on $(cc-option,-gdwarf-4)
+ select DEBUG_INFO_AS_DWARF4
help
Generate dwarf4 debug info. This requires recent versions
of gcc and gdb. It makes the debug information larger.
NOTE: This is on top of Linux v5.8 vanilla.
NOTE-2: When building with LLVM toolchain v11.0.0-rc1+ and especially
with LLVM_IAS=1 (and LLVM=1) DWARF version 4 is a good choice.
For details see below links.
Thoughts?
Regards,
- Sedat -
[1] https://github.com/ClangBuiltLinux/linux/issues/1086
[2] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674503335
[3] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674517876
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4
2020-08-16 12:14 Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4 Sedat Dilek
@ 2020-08-26 12:11 ` Sedat Dilek
2020-08-26 14:36 ` Sedat Dilek
0 siblings, 1 reply; 4+ messages in thread
From: Sedat Dilek @ 2020-08-26 12:11 UTC (permalink / raw)
To: Masahiro Yamada; +Cc: linux-kbuild, Sami Tolvanen
On Sun, Aug 16, 2020 at 2:14 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
>
> Hi Masahiro,
>
> I wondered why my generated linux-image-db Debian packages were so big
> when I use GCC toolchain instead of LLVM toolchain.
>
> It turned out I mixed both...
>
> KBUILD_AFLAGS += -Wa,-gdwarf-2
>
> ...together with...
>
> DEBUG_CFLAGS += -gdwarf-4
>
> ...when CONFIG_DEBUG_INFO_DWARF4=y is set.
>
> So I hacked up something like the following to prevent this:
>
> diff --git a/Makefile b/Makefile
> index 24a4c1b97bb0..e7a8e47b0e34 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -815,7 +815,11 @@ DEBUG_CFLAGS += -gsplit-dwarf
> else
> DEBUG_CFLAGS += -g
> endif
> +ifdef CONFIG_DEBUG_INFO_AS_DWARF2
> KBUILD_AFLAGS += -Wa,-gdwarf-2
> +else ifdef CONFIG_DEBUG_INFO_AS_DWARF4
> +KBUILD_AFLAGS += -Wa,-gdwarf-4
> +endif
> endif
> ifdef CONFIG_DEBUG_INFO_DWARF4
> DEBUG_CFLAGS += -gdwarf-4
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 9ad9210d70a1..9f11fc71462c 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -257,10 +257,23 @@ config DEBUG_INFO_SPLIT
> to know about the .dwo files and include them.
> Incompatible with older versions of ccache.
>
> +config DEBUG_INFO_AS_DWARF2
> + bool "Use DWARF-2 assembler option with debuginfo"
> + depends on $(cc-option,-Wa$(comma)-gdwarf-2)
> + help
> + Set DWARF-2 assembler option with debuginfo
> +
> +config DEBUG_INFO_AS_DWARF4
> + bool "Use DWARF-4 assembler option with debuginfo"
> + depends on $(cc-option,-Wa$(comma)-gdwarf-4)
> + help
> + Set DWARF-4 assembler option with debuginfo
> +
> config DEBUG_INFO_DWARF4
> bool "Generate dwarf4 debuginfo"
> depends on DEBUG_INFO
> depends on $(cc-option,-gdwarf-4)
> + select DEBUG_INFO_AS_DWARF4
> help
> Generate dwarf4 debug info. This requires recent versions
> of gcc and gdb. It makes the debug information larger.
>
> NOTE: This is on top of Linux v5.8 vanilla.
>
> NOTE-2: When building with LLVM toolchain v11.0.0-rc1+ and especially
> with LLVM_IAS=1 (and LLVM=1) DWARF version 4 is a good choice.
>
> For details see below links.
>
> Thoughts?
>
> Regards,
> - Sedat -
>
> [1] https://github.com/ClangBuiltLinux/linux/issues/1086
> [2] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674503335
> [3] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674517876
[ CC Sami ]
Hi,
while playing with Clang-CFI I needed this patch to fix these warnings:
$ grep DWARF BROKEN_DWARF2-only-supports-one-section-per-compilation-unit.txt
arch/x86/crypto/twofish-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/twofish-avx-x86_64-asm_64.S:22:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/serpent-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/serpent-avx-x86_64-asm_64.S:21:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/serpent-avx2-asm_64.S:18:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/serpent-avx2-asm_64.S:23:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/serpent-avx2-asm_64.S:28:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/des3_ede-asm_64.S:534:1: warning: DWARF2 only supports
one section per compilation unit
arch/x86/crypto/camellia-aesni-avx-asm_64.S:577:1: warning: DWARF2
only supports one section per compilation unit
arch/x86/crypto/camellia-aesni-avx-asm_64.S:717:1: warning: DWARF2
only supports one section per compilation unit
<instantiation>:2:2: warning: DWARF2 only supports one section per
compilation unit
<instantiation>:8:2: warning: DWARF2 only supports one section per
compilation unit
<instantiation>:13:2: warning: DWARF2 only supports one section per
compilation unit
arch/x86/crypto/camellia-aesni-avx2-asm_64.S:610:1: warning: DWARF2
only supports one section per compilation unit
arch/x86/crypto/camellia-aesni-avx2-asm_64.S:618:1: warning: DWARF2
only supports one section per compilation unit
arch/x86/crypto/camellia-aesni-avx2-asm_64.S:625:1: warning: DWARF2
only supports one section per compilation unit
arch/x86/crypto/camellia-aesni-avx2-asm_64.S:754:1: warning: DWARF2
only supports one section per compilation unit
<instantiation>:2:2: warning: DWARF2 only supports one section per
compilation unit
<instantiation>:8:2: warning: DWARF2 only supports one section per
compilation unit
<instantiation>:13:2: warning: DWARF2 only supports one section per
compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:183:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:187:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:191:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:196:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:200:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast5-avx-x86_64-asm_64.S:204:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast6-avx-x86_64-asm_64.S:213:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast6-avx-x86_64-asm_64.S:232:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast6-avx-x86_64-asm_64.S:237:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/cast6-avx-x86_64-asm_64.S:242:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/aegis128-aesni-asm.S:27:1: warning: DWARF2 only
supports one section per compilation unit
arch/x86/crypto/aegis128-aesni-asm.S:36:1: warning: DWARF2 only
supports one section per compilation unit
Can you please review?
Thanks.
Regards,
- Sedat -
P.S.: With the help of Sami I can now build and boot into Linux-kernel
with Clang-CFI support enabled.
[1] https://github.com/samitolvanen/linux/commits/clang-cfi
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4
2020-08-26 12:11 ` Sedat Dilek
@ 2020-08-26 14:36 ` Sedat Dilek
2020-08-26 16:05 ` Sedat Dilek
0 siblings, 1 reply; 4+ messages in thread
From: Sedat Dilek @ 2020-08-26 14:36 UTC (permalink / raw)
To: Masahiro Yamada; +Cc: linux-kbuild, Sami Tolvanen
On Wed, Aug 26, 2020 at 2:11 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
>
> On Sun, Aug 16, 2020 at 2:14 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
> >
> > Hi Masahiro,
> >
> > I wondered why my generated linux-image-db Debian packages were so big
> > when I use GCC toolchain instead of LLVM toolchain.
> >
> > It turned out I mixed both...
> >
> > KBUILD_AFLAGS += -Wa,-gdwarf-2
> >
> > ...together with...
> >
> > DEBUG_CFLAGS += -gdwarf-4
> >
> > ...when CONFIG_DEBUG_INFO_DWARF4=y is set.
> >
> > So I hacked up something like the following to prevent this:
> >
> > diff --git a/Makefile b/Makefile
> > index 24a4c1b97bb0..e7a8e47b0e34 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -815,7 +815,11 @@ DEBUG_CFLAGS += -gsplit-dwarf
> > else
> > DEBUG_CFLAGS += -g
> > endif
> > +ifdef CONFIG_DEBUG_INFO_AS_DWARF2
> > KBUILD_AFLAGS += -Wa,-gdwarf-2
> > +else ifdef CONFIG_DEBUG_INFO_AS_DWARF4
> > +KBUILD_AFLAGS += -Wa,-gdwarf-4
> > +endif
> > endif
> > ifdef CONFIG_DEBUG_INFO_DWARF4
> > DEBUG_CFLAGS += -gdwarf-4
> > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> > index 9ad9210d70a1..9f11fc71462c 100644
> > --- a/lib/Kconfig.debug
> > +++ b/lib/Kconfig.debug
> > @@ -257,10 +257,23 @@ config DEBUG_INFO_SPLIT
> > to know about the .dwo files and include them.
> > Incompatible with older versions of ccache.
> >
> > +config DEBUG_INFO_AS_DWARF2
> > + bool "Use DWARF-2 assembler option with debuginfo"
> > + depends on $(cc-option,-Wa$(comma)-gdwarf-2)
> > + help
> > + Set DWARF-2 assembler option with debuginfo
> > +
> > +config DEBUG_INFO_AS_DWARF4
> > + bool "Use DWARF-4 assembler option with debuginfo"
> > + depends on $(cc-option,-Wa$(comma)-gdwarf-4)
> > + help
> > + Set DWARF-4 assembler option with debuginfo
> > +
> > config DEBUG_INFO_DWARF4
> > bool "Generate dwarf4 debuginfo"
> > depends on DEBUG_INFO
> > depends on $(cc-option,-gdwarf-4)
> > + select DEBUG_INFO_AS_DWARF4
> > help
> > Generate dwarf4 debug info. This requires recent versions
> > of gcc and gdb. It makes the debug information larger.
> >
> > NOTE: This is on top of Linux v5.8 vanilla.
> >
> > NOTE-2: When building with LLVM toolchain v11.0.0-rc1+ and especially
> > with LLVM_IAS=1 (and LLVM=1) DWARF version 4 is a good choice.
> >
> > For details see below links.
> >
> > Thoughts?
> >
> > Regards,
> > - Sedat -
> >
> > [1] https://github.com/ClangBuiltLinux/linux/issues/1086
> > [2] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674503335
> > [3] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674517876
>
> [ CC Sami ]
>
> Hi,
>
> while playing with Clang-CFI I needed this patch to fix these warnings:
>
> $ grep DWARF BROKEN_DWARF2-only-supports-one-section-per-compilation-unit.txt
> arch/x86/crypto/twofish-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/twofish-avx-x86_64-asm_64.S:22:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/serpent-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/serpent-avx-x86_64-asm_64.S:21:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/serpent-avx2-asm_64.S:18:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/serpent-avx2-asm_64.S:23:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/serpent-avx2-asm_64.S:28:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/des3_ede-asm_64.S:534:1: warning: DWARF2 only supports
> one section per compilation unit
> arch/x86/crypto/camellia-aesni-avx-asm_64.S:577:1: warning: DWARF2
> only supports one section per compilation unit
> arch/x86/crypto/camellia-aesni-avx-asm_64.S:717:1: warning: DWARF2
> only supports one section per compilation unit
> <instantiation>:2:2: warning: DWARF2 only supports one section per
> compilation unit
> <instantiation>:8:2: warning: DWARF2 only supports one section per
> compilation unit
> <instantiation>:13:2: warning: DWARF2 only supports one section per
> compilation unit
> arch/x86/crypto/camellia-aesni-avx2-asm_64.S:610:1: warning: DWARF2
> only supports one section per compilation unit
> arch/x86/crypto/camellia-aesni-avx2-asm_64.S:618:1: warning: DWARF2
> only supports one section per compilation unit
> arch/x86/crypto/camellia-aesni-avx2-asm_64.S:625:1: warning: DWARF2
> only supports one section per compilation unit
> arch/x86/crypto/camellia-aesni-avx2-asm_64.S:754:1: warning: DWARF2
> only supports one section per compilation unit
> <instantiation>:2:2: warning: DWARF2 only supports one section per
> compilation unit
> <instantiation>:8:2: warning: DWARF2 only supports one section per
> compilation unit
> <instantiation>:13:2: warning: DWARF2 only supports one section per
> compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:183:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:187:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:191:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:196:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:200:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast5-avx-x86_64-asm_64.S:204:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast6-avx-x86_64-asm_64.S:213:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast6-avx-x86_64-asm_64.S:232:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast6-avx-x86_64-asm_64.S:237:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/cast6-avx-x86_64-asm_64.S:242:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/aegis128-aesni-asm.S:27:1: warning: DWARF2 only
> supports one section per compilation unit
> arch/x86/crypto/aegis128-aesni-asm.S:36:1: warning: DWARF2 only
> supports one section per compilation unit
>
> Can you please review?
>
> Thanks.
>
> Regards,
> - Sedat -
>
> P.S.: With the help of Sami I can now build and boot into Linux-kernel
> with Clang-CFI support enabled.
>
> [1] https://github.com/samitolvanen/linux/commits/clang-cfi
Some more informations to clarify this is really needed.
I switched over to DWARF version 4 when dealing with Clang-IAS
(integrated assembler).
And saw similar problems.
This was always with...
CONFIG_DEBUG_INFO_DWARF4=y
There are 156 places here on x86 64bit...
[ Clang-CFI ]
$ grep '\-Wa,-gdwarf-4' build-log_5.9.0-rc2-5-amd64-llvm11-cfi.txt | wc -l
156
[ Clang-LTO ]
$ grep '\-Wa,-gdwarf-4' build-log_5.9.0-rc2-6-amd64-clang-lto.txt | wc -l
156
- Sedat -
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4
2020-08-26 14:36 ` Sedat Dilek
@ 2020-08-26 16:05 ` Sedat Dilek
0 siblings, 0 replies; 4+ messages in thread
From: Sedat Dilek @ 2020-08-26 16:05 UTC (permalink / raw)
To: Masahiro Yamada; +Cc: linux-kbuild, Sami Tolvanen
On Wed, Aug 26, 2020 at 4:36 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
>
> On Wed, Aug 26, 2020 at 2:11 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
> >
> > On Sun, Aug 16, 2020 at 2:14 PM Sedat Dilek <sedat.dilek@gmail.com> wrote:
> > >
> > > Hi Masahiro,
> > >
> > > I wondered why my generated linux-image-db Debian packages were so big
> > > when I use GCC toolchain instead of LLVM toolchain.
> > >
> > > It turned out I mixed both...
> > >
> > > KBUILD_AFLAGS += -Wa,-gdwarf-2
> > >
> > > ...together with...
> > >
> > > DEBUG_CFLAGS += -gdwarf-4
> > >
> > > ...when CONFIG_DEBUG_INFO_DWARF4=y is set.
> > >
> > > So I hacked up something like the following to prevent this:
> > >
> > > diff --git a/Makefile b/Makefile
> > > index 24a4c1b97bb0..e7a8e47b0e34 100644
> > > --- a/Makefile
> > > +++ b/Makefile
> > > @@ -815,7 +815,11 @@ DEBUG_CFLAGS += -gsplit-dwarf
> > > else
> > > DEBUG_CFLAGS += -g
> > > endif
> > > +ifdef CONFIG_DEBUG_INFO_AS_DWARF2
> > > KBUILD_AFLAGS += -Wa,-gdwarf-2
> > > +else ifdef CONFIG_DEBUG_INFO_AS_DWARF4
> > > +KBUILD_AFLAGS += -Wa,-gdwarf-4
> > > +endif
> > > endif
> > > ifdef CONFIG_DEBUG_INFO_DWARF4
> > > DEBUG_CFLAGS += -gdwarf-4
> > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> > > index 9ad9210d70a1..9f11fc71462c 100644
> > > --- a/lib/Kconfig.debug
> > > +++ b/lib/Kconfig.debug
> > > @@ -257,10 +257,23 @@ config DEBUG_INFO_SPLIT
> > > to know about the .dwo files and include them.
> > > Incompatible with older versions of ccache.
> > >
> > > +config DEBUG_INFO_AS_DWARF2
> > > + bool "Use DWARF-2 assembler option with debuginfo"
> > > + depends on $(cc-option,-Wa$(comma)-gdwarf-2)
> > > + help
> > > + Set DWARF-2 assembler option with debuginfo
> > > +
> > > +config DEBUG_INFO_AS_DWARF4
> > > + bool "Use DWARF-4 assembler option with debuginfo"
> > > + depends on $(cc-option,-Wa$(comma)-gdwarf-4)
> > > + help
> > > + Set DWARF-4 assembler option with debuginfo
> > > +
> > > config DEBUG_INFO_DWARF4
> > > bool "Generate dwarf4 debuginfo"
> > > depends on DEBUG_INFO
> > > depends on $(cc-option,-gdwarf-4)
> > > + select DEBUG_INFO_AS_DWARF4
> > > help
> > > Generate dwarf4 debug info. This requires recent versions
> > > of gcc and gdb. It makes the debug information larger.
> > >
> > > NOTE: This is on top of Linux v5.8 vanilla.
> > >
> > > NOTE-2: When building with LLVM toolchain v11.0.0-rc1+ and especially
> > > with LLVM_IAS=1 (and LLVM=1) DWARF version 4 is a good choice.
> > >
> > > For details see below links.
> > >
> > > Thoughts?
> > >
> > > Regards,
> > > - Sedat -
> > >
> > > [1] https://github.com/ClangBuiltLinux/linux/issues/1086
> > > [2] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674503335
> > > [3] https://github.com/ClangBuiltLinux/linux/issues/1086#issuecomment-674517876
> >
> > [ CC Sami ]
> >
> > Hi,
> >
> > while playing with Clang-CFI I needed this patch to fix these warnings:
> >
> > $ grep DWARF BROKEN_DWARF2-only-supports-one-section-per-compilation-unit.txt
> > arch/x86/crypto/twofish-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/twofish-avx-x86_64-asm_64.S:22:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/serpent-avx-x86_64-asm_64.S:17:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/serpent-avx-x86_64-asm_64.S:21:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/serpent-avx2-asm_64.S:18:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/serpent-avx2-asm_64.S:23:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/serpent-avx2-asm_64.S:28:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/des3_ede-asm_64.S:534:1: warning: DWARF2 only supports
> > one section per compilation unit
> > arch/x86/crypto/camellia-aesni-avx-asm_64.S:577:1: warning: DWARF2
> > only supports one section per compilation unit
> > arch/x86/crypto/camellia-aesni-avx-asm_64.S:717:1: warning: DWARF2
> > only supports one section per compilation unit
> > <instantiation>:2:2: warning: DWARF2 only supports one section per
> > compilation unit
> > <instantiation>:8:2: warning: DWARF2 only supports one section per
> > compilation unit
> > <instantiation>:13:2: warning: DWARF2 only supports one section per
> > compilation unit
> > arch/x86/crypto/camellia-aesni-avx2-asm_64.S:610:1: warning: DWARF2
> > only supports one section per compilation unit
> > arch/x86/crypto/camellia-aesni-avx2-asm_64.S:618:1: warning: DWARF2
> > only supports one section per compilation unit
> > arch/x86/crypto/camellia-aesni-avx2-asm_64.S:625:1: warning: DWARF2
> > only supports one section per compilation unit
> > arch/x86/crypto/camellia-aesni-avx2-asm_64.S:754:1: warning: DWARF2
> > only supports one section per compilation unit
> > <instantiation>:2:2: warning: DWARF2 only supports one section per
> > compilation unit
> > <instantiation>:8:2: warning: DWARF2 only supports one section per
> > compilation unit
> > <instantiation>:13:2: warning: DWARF2 only supports one section per
> > compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:183:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:187:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:191:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:196:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:200:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast5-avx-x86_64-asm_64.S:204:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast6-avx-x86_64-asm_64.S:213:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast6-avx-x86_64-asm_64.S:232:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast6-avx-x86_64-asm_64.S:237:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/cast6-avx-x86_64-asm_64.S:242:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/aegis128-aesni-asm.S:27:1: warning: DWARF2 only
> > supports one section per compilation unit
> > arch/x86/crypto/aegis128-aesni-asm.S:36:1: warning: DWARF2 only
> > supports one section per compilation unit
> >
> > Can you please review?
> >
> > Thanks.
> >
> > Regards,
> > - Sedat -
> >
> > P.S.: With the help of Sami I can now build and boot into Linux-kernel
> > with Clang-CFI support enabled.
> >
> > [1] https://github.com/samitolvanen/linux/commits/clang-cfi
>
> Some more informations to clarify this is really needed.
>
> I switched over to DWARF version 4 when dealing with Clang-IAS
> (integrated assembler).
> And saw similar problems.
>
> This was always with...
>
> CONFIG_DEBUG_INFO_DWARF4=y
>
> There are 156 places here on x86 64bit...
>
> [ Clang-CFI ]
>
> $ grep '\-Wa,-gdwarf-4' build-log_5.9.0-rc2-5-amd64-llvm11-cfi.txt | wc -l
> 156
>
> [ Clang-LTO ]
>
> $ grep '\-Wa,-gdwarf-4' build-log_5.9.0-rc2-6-amd64-clang-lto.txt | wc -l
> 156
>
Hi Masahiro,
I would send a proper patch with all related information when you
agree with the handling of CONFIG_DEBUG_INFO_AS_DWARF{2,4}.
Just as note:
I tested this also with GNU/ld (BFD) version 2.35 with preliminary
DWARF4 support.
Thanks.
Regards,
- Sedat -
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-08-26 16:05 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-16 12:14 Introduce CONFIG_DEBUG_INFO_AS_DWARF2 and CONFIG_DEBUG_INFO_AS_DWARF4 Sedat Dilek
2020-08-26 12:11 ` Sedat Dilek
2020-08-26 14:36 ` Sedat Dilek
2020-08-26 16:05 ` Sedat Dilek
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