* resolve_btfids breaks kernel cross-compilation
@ 2020-09-16 19:47 Seth Forshee
2020-09-17 8:04 ` Jiri Olsa
0 siblings, 1 reply; 8+ messages in thread
From: Seth Forshee @ 2020-09-16 19:47 UTC (permalink / raw)
To: Jiri Olsa; +Cc: Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel
The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF
is enabled breaks some cross builds. For example, when building a 64-bit
powerpc kernel on amd64 I get:
Auto-detecting system features:
... libelf: [ [32mon[m ]
... zlib: [ [32mon[m ]
... bpf: [ [31mOFF[m ]
BPF API too old
make[6]: *** [Makefile:295: bpfdep] Error 1
The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output:
In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11,
from /usr/include/asm-generic/int-ll64.h:12,
from /usr/include/asm-generic/types.h:7,
from /usr/include/x86_64-linux-gnu/asm/types.h:1,
from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10,
from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11,
from test-bpf.c:3:
/home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h
14 | #error Inconsistent word size. Check asm/bitsperlong.h
| ^~~~~
This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets
__BITS_PER_LONG based on the predefinied compiler macro __powerpc64__,
which is not defined by the host compiler. What can we do to get cross
builds working again?
Thanks,
Seth
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: resolve_btfids breaks kernel cross-compilation 2020-09-16 19:47 resolve_btfids breaks kernel cross-compilation Seth Forshee @ 2020-09-17 8:04 ` Jiri Olsa 2020-09-17 8:38 ` Jiri Olsa 0 siblings, 1 reply; 8+ messages in thread From: Jiri Olsa @ 2020-09-17 8:04 UTC (permalink / raw) To: Seth Forshee Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > is enabled breaks some cross builds. For example, when building a 64-bit > powerpc kernel on amd64 I get: > > Auto-detecting system features: > ... libelf: [ [32mon[m ] > ... zlib: [ [32mon[m ] > ... bpf: [ [31mOFF[m ] > > BPF API too old > make[6]: *** [Makefile:295: bpfdep] Error 1 > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > from /usr/include/asm-generic/int-ll64.h:12, > from /usr/include/asm-generic/types.h:7, > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > from test-bpf.c:3: > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > | ^~~~~ > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > which is not defined by the host compiler. What can we do to get cross > builds working again? could you please share the command line and setup? thanks, jirka ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-17 8:04 ` Jiri Olsa @ 2020-09-17 8:38 ` Jiri Olsa 2020-09-17 9:14 ` Jiri Olsa 0 siblings, 1 reply; 8+ messages in thread From: Jiri Olsa @ 2020-09-17 8:38 UTC (permalink / raw) To: Seth Forshee Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > is enabled breaks some cross builds. For example, when building a 64-bit > > powerpc kernel on amd64 I get: > > > > Auto-detecting system features: > > ... libelf: [ [32mon[m ] > > ... zlib: [ [32mon[m ] > > ... bpf: [ [31mOFF[m ] > > > > BPF API too old > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > from /usr/include/asm-generic/int-ll64.h:12, > > from /usr/include/asm-generic/types.h:7, > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > from test-bpf.c:3: > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > | ^~~~~ > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > which is not defined by the host compiler. What can we do to get cross > > builds working again? > > could you please share the command line and setup? I just reproduced.. checking on fix jirka ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-17 8:38 ` Jiri Olsa @ 2020-09-17 9:14 ` Jiri Olsa 2020-09-17 9:54 ` Jiri Olsa 2020-09-17 12:54 ` Seth Forshee 0 siblings, 2 replies; 8+ messages in thread From: Jiri Olsa @ 2020-09-17 9:14 UTC (permalink / raw) To: Seth Forshee Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Thu, Sep 17, 2020 at 10:38:12AM +0200, Jiri Olsa wrote: > On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > > is enabled breaks some cross builds. For example, when building a 64-bit > > > powerpc kernel on amd64 I get: > > > > > > Auto-detecting system features: > > > ... libelf: [ [32mon[m ] > > > ... zlib: [ [32mon[m ] > > > ... bpf: [ [31mOFF[m ] > > > > > > BPF API too old > > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > > from /usr/include/asm-generic/int-ll64.h:12, > > > from /usr/include/asm-generic/types.h:7, > > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > > from test-bpf.c:3: > > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > > | ^~~~~ > > > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > > which is not defined by the host compiler. What can we do to get cross > > > builds working again? > > > > could you please share the command line and setup? > > I just reproduced.. checking on fix I still need to check on few things, but patch below should help we might have a problem for cross builds with different endianity than the host because libbpf does not support reading BTF data with different endianity, and we get: BTFIDS vmlinux libbpf: non-native ELF endianness is not supported jirka --- diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile index a88cd4426398..d3c818b8d8d3 100644 --- a/tools/bpf/resolve_btfids/Makefile +++ b/tools/bpf/resolve_btfids/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only include ../../scripts/Makefile.include +include ../../scripts/Makefile.arch ifeq ($(srctree),) srctree := $(patsubst %/,%,$(dir $(CURDIR))) @@ -29,6 +30,7 @@ endif AR = $(HOSTAR) CC = $(HOSTCC) LD = $(HOSTLD) +ARCH = $(HOSTARCH) OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-17 9:14 ` Jiri Olsa @ 2020-09-17 9:54 ` Jiri Olsa 2020-09-17 12:54 ` Seth Forshee 1 sibling, 0 replies; 8+ messages in thread From: Jiri Olsa @ 2020-09-17 9:54 UTC (permalink / raw) To: Seth Forshee Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Thu, Sep 17, 2020 at 11:14:08AM +0200, Jiri Olsa wrote: > On Thu, Sep 17, 2020 at 10:38:12AM +0200, Jiri Olsa wrote: > > On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > > > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > > > is enabled breaks some cross builds. For example, when building a 64-bit > > > > powerpc kernel on amd64 I get: > > > > > > > > Auto-detecting system features: > > > > ... libelf: [ [32mon[m ] > > > > ... zlib: [ [32mon[m ] > > > > ... bpf: [ [31mOFF[m ] > > > > > > > > BPF API too old > > > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > > > from /usr/include/asm-generic/int-ll64.h:12, > > > > from /usr/include/asm-generic/types.h:7, > > > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > > > from test-bpf.c:3: > > > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > > > | ^~~~~ > > > > > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > > > which is not defined by the host compiler. What can we do to get cross > > > > builds working again? > > > > > > could you please share the command line and setup? > > > > I just reproduced.. checking on fix > > I still need to check on few things, but patch below should help > > we might have a problem for cross builds with different endianity > than the host because libbpf does not support reading BTF data > with different endianity, and we get: > > BTFIDS vmlinux > libbpf: non-native ELF endianness is not supported > > jirka > > > --- > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile > index a88cd4426398..d3c818b8d8d3 100644 > --- a/tools/bpf/resolve_btfids/Makefile > +++ b/tools/bpf/resolve_btfids/Makefile > @@ -1,5 +1,6 @@ > # SPDX-License-Identifier: GPL-2.0-only > include ../../scripts/Makefile.include > +include ../../scripts/Makefile.arch > > ifeq ($(srctree),) > srctree := $(patsubst %/,%,$(dir $(CURDIR))) > @@ -29,6 +30,7 @@ endif > AR = $(HOSTAR) > CC = $(HOSTCC) > LD = $(HOSTLD) > +ARCH = $(HOSTARCH) > > OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ > and I realized we can have CONFIG_DEBUG_INFO_BTF without CONFIG_BPF, so we need also fix below for such cases jirka --- diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index e6e2d9e5ff48..8a990933a690 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -343,7 +343,10 @@ vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o} # fill in BTF IDs if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then info BTFIDS vmlinux -${RESOLVE_BTFIDS} vmlinux +if [ -z "${CONFIG_BPF}" ]; then + no_fail=--no-fail +fi +${RESOLVE_BTFIDS} $no_fail vmlinux fi if [ -n "${CONFIG_BUILDTIME_TABLE_SORT}" ]; then ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-17 9:14 ` Jiri Olsa 2020-09-17 9:54 ` Jiri Olsa @ 2020-09-17 12:54 ` Seth Forshee 2020-09-18 10:05 ` Jiri Olsa 1 sibling, 1 reply; 8+ messages in thread From: Seth Forshee @ 2020-09-17 12:54 UTC (permalink / raw) To: Jiri Olsa Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Thu, Sep 17, 2020 at 11:14:06AM +0200, Jiri Olsa wrote: > On Thu, Sep 17, 2020 at 10:38:12AM +0200, Jiri Olsa wrote: > > On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > > > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > > > is enabled breaks some cross builds. For example, when building a 64-bit > > > > powerpc kernel on amd64 I get: > > > > > > > > Auto-detecting system features: > > > > ... libelf: [ [32mon[m ] > > > > ... zlib: [ [32mon[m ] > > > > ... bpf: [ [31mOFF[m ] > > > > > > > > BPF API too old > > > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > > > from /usr/include/asm-generic/int-ll64.h:12, > > > > from /usr/include/asm-generic/types.h:7, > > > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > > > from test-bpf.c:3: > > > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > > > | ^~~~~ > > > > > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > > > which is not defined by the host compiler. What can we do to get cross > > > > builds working again? > > > > > > could you please share the command line and setup? > > > > I just reproduced.. checking on fix > > I still need to check on few things, but patch below should help It does help with the word size problem, thanks. > we might have a problem for cross builds with different endianity > than the host because libbpf does not support reading BTF data > with different endianity, and we get: > > BTFIDS vmlinux > libbpf: non-native ELF endianness is not supported Yes, I see this now when cross building for s390. Thanks, Seth > > jirka > > > --- > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile > index a88cd4426398..d3c818b8d8d3 100644 > --- a/tools/bpf/resolve_btfids/Makefile > +++ b/tools/bpf/resolve_btfids/Makefile > @@ -1,5 +1,6 @@ > # SPDX-License-Identifier: GPL-2.0-only > include ../../scripts/Makefile.include > +include ../../scripts/Makefile.arch > > ifeq ($(srctree),) > srctree := $(patsubst %/,%,$(dir $(CURDIR))) > @@ -29,6 +30,7 @@ endif > AR = $(HOSTAR) > CC = $(HOSTCC) > LD = $(HOSTLD) > +ARCH = $(HOSTARCH) > > OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-17 12:54 ` Seth Forshee @ 2020-09-18 10:05 ` Jiri Olsa 2020-09-18 18:50 ` Andrii Nakryiko 0 siblings, 1 reply; 8+ messages in thread From: Jiri Olsa @ 2020-09-18 10:05 UTC (permalink / raw) To: Seth Forshee, Andrii Nakryiko Cc: Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, netdev, bpf, linux-kernel On Thu, Sep 17, 2020 at 07:54:50AM -0500, Seth Forshee wrote: > On Thu, Sep 17, 2020 at 11:14:06AM +0200, Jiri Olsa wrote: > > On Thu, Sep 17, 2020 at 10:38:12AM +0200, Jiri Olsa wrote: > > > On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > > > > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > > > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > > > > is enabled breaks some cross builds. For example, when building a 64-bit > > > > > powerpc kernel on amd64 I get: > > > > > > > > > > Auto-detecting system features: > > > > > ... libelf: [ [32mon[m ] > > > > > ... zlib: [ [32mon[m ] > > > > > ... bpf: [ [31mOFF[m ] > > > > > > > > > > BPF API too old > > > > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > > > > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > > > > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > > > > from /usr/include/asm-generic/int-ll64.h:12, > > > > > from /usr/include/asm-generic/types.h:7, > > > > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > > > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > > > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > > > > from test-bpf.c:3: > > > > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > > > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > > > > | ^~~~~ > > > > > > > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > > > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > > > > which is not defined by the host compiler. What can we do to get cross > > > > > builds working again? > > > > > > > > could you please share the command line and setup? > > > > > > I just reproduced.. checking on fix > > > > I still need to check on few things, but patch below should help > > It does help with the word size problem, thanks. > > > we might have a problem for cross builds with different endianity > > than the host because libbpf does not support reading BTF data > > with different endianity, and we get: > > > > BTFIDS vmlinux > > libbpf: non-native ELF endianness is not supported > > Yes, I see this now when cross building for s390. Andrii, I read you might be already working on this? https://lore.kernel.org/bpf/CAEf4Bza9tZ-Jj0dj9Ne0fmxa95t=9XxxJR+Ce=6hDmw_d8uVFA@mail.gmail.com/ thanks, jirka > > Thanks, > Seth > > > > > jirka > > > > > > --- > > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile > > index a88cd4426398..d3c818b8d8d3 100644 > > --- a/tools/bpf/resolve_btfids/Makefile > > +++ b/tools/bpf/resolve_btfids/Makefile > > @@ -1,5 +1,6 @@ > > # SPDX-License-Identifier: GPL-2.0-only > > include ../../scripts/Makefile.include > > +include ../../scripts/Makefile.arch > > > > ifeq ($(srctree),) > > srctree := $(patsubst %/,%,$(dir $(CURDIR))) > > @@ -29,6 +30,7 @@ endif > > AR = $(HOSTAR) > > CC = $(HOSTCC) > > LD = $(HOSTLD) > > +ARCH = $(HOSTARCH) > > > > OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ > > > > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: resolve_btfids breaks kernel cross-compilation 2020-09-18 10:05 ` Jiri Olsa @ 2020-09-18 18:50 ` Andrii Nakryiko 0 siblings, 0 replies; 8+ messages in thread From: Andrii Nakryiko @ 2020-09-18 18:50 UTC (permalink / raw) To: Jiri Olsa Cc: Seth Forshee, Andrii Nakryiko, Jiri Olsa, Alexei Starovoitov, Daniel Borkmann, Networking, bpf, open list On Fri, Sep 18, 2020 at 3:07 AM Jiri Olsa <jolsa@redhat.com> wrote: > > On Thu, Sep 17, 2020 at 07:54:50AM -0500, Seth Forshee wrote: > > On Thu, Sep 17, 2020 at 11:14:06AM +0200, Jiri Olsa wrote: > > > On Thu, Sep 17, 2020 at 10:38:12AM +0200, Jiri Olsa wrote: > > > > On Thu, Sep 17, 2020 at 10:04:55AM +0200, Jiri Olsa wrote: > > > > > On Wed, Sep 16, 2020 at 02:47:33PM -0500, Seth Forshee wrote: > > > > > > The requirement to build resolve_btfids whenever CONFIG_DEBUG_INFO_BTF > > > > > > is enabled breaks some cross builds. For example, when building a 64-bit > > > > > > powerpc kernel on amd64 I get: > > > > > > > > > > > > Auto-detecting system features: > > > > > > ... libelf: [ [32mon[m ] > > > > > > ... zlib: [ [32mon[m ] > > > > > > ... bpf: [ [31mOFF[m ] > > > > > > > > > > > > BPF API too old > > > > > > make[6]: *** [Makefile:295: bpfdep] Error 1 > > > > > > > > > > > > The contents of tools/bpf/resolve_btfids/feature/test-bpf.make.output: > > > > > > > > > > > > In file included from /home/sforshee/src/u-k/unstable/tools/arch/powerpc/include/uapi/asm/bitsperlong.h:11, > > > > > > from /usr/include/asm-generic/int-ll64.h:12, > > > > > > from /usr/include/asm-generic/types.h:7, > > > > > > from /usr/include/x86_64-linux-gnu/asm/types.h:1, > > > > > > from /home/sforshee/src/u-k/unstable/tools/include/linux/types.h:10, > > > > > > from /home/sforshee/src/u-k/unstable/tools/include/uapi/linux/bpf.h:11, > > > > > > from test-bpf.c:3: > > > > > > /home/sforshee/src/u-k/unstable/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h > > > > > > 14 | #error Inconsistent word size. Check asm/bitsperlong.h > > > > > > | ^~~~~ > > > > > > > > > > > > This is because tools/arch/powerpc/include/uapi/asm/bitsperlong.h sets > > > > > > __BITS_PER_LONG based on the predefinied compiler macro __powerpc64__, > > > > > > which is not defined by the host compiler. What can we do to get cross > > > > > > builds working again? > > > > > > > > > > could you please share the command line and setup? > > > > > > > > I just reproduced.. checking on fix > > > > > > I still need to check on few things, but patch below should help > > > > It does help with the word size problem, thanks. > > > > > we might have a problem for cross builds with different endianity > > > than the host because libbpf does not support reading BTF data > > > with different endianity, and we get: > > > > > > BTFIDS vmlinux > > > libbpf: non-native ELF endianness is not supported > > > > Yes, I see this now when cross building for s390. > > Andrii, > I read you might be already working on this? > https://lore.kernel.org/bpf/CAEf4Bza9tZ-Jj0dj9Ne0fmxa95t=9XxxJR+Ce=6hDmw_d8uVFA@mail.gmail.com/ > Yes, it's one of the limitations I'm solving, stay tuned. > thanks, > jirka > > > > > Thanks, > > Seth > > > > > > > > jirka > > > > > > > > > --- > > > diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile > > > index a88cd4426398..d3c818b8d8d3 100644 > > > --- a/tools/bpf/resolve_btfids/Makefile > > > +++ b/tools/bpf/resolve_btfids/Makefile > > > @@ -1,5 +1,6 @@ > > > # SPDX-License-Identifier: GPL-2.0-only > > > include ../../scripts/Makefile.include > > > +include ../../scripts/Makefile.arch > > > > > > ifeq ($(srctree),) > > > srctree := $(patsubst %/,%,$(dir $(CURDIR))) > > > @@ -29,6 +30,7 @@ endif > > > AR = $(HOSTAR) > > > CC = $(HOSTCC) > > > LD = $(HOSTLD) > > > +ARCH = $(HOSTARCH) > > > > > > OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ > > > > > > > > > ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2020-09-18 18:50 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2020-09-16 19:47 resolve_btfids breaks kernel cross-compilation Seth Forshee 2020-09-17 8:04 ` Jiri Olsa 2020-09-17 8:38 ` Jiri Olsa 2020-09-17 9:14 ` Jiri Olsa 2020-09-17 9:54 ` Jiri Olsa 2020-09-17 12:54 ` Seth Forshee 2020-09-18 10:05 ` Jiri Olsa 2020-09-18 18:50 ` Andrii Nakryiko
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).