| Message ID | 1655982614-13571-1-git-send-email-alan.maguire@oracle.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf-next] selftests/bpf: support building selftests when CONFIG_NF_CONNTRACK=m | expand |
On Thu, Jun 23, 2022 at 4:10 AM Alan Maguire <alan.maguire@oracle.com> wrote: > > when CONFIG_NF_CONNTRACK=m, vmlinux BTF does not contain > BPF_F_CURRENT_NETNS or bpf_ct_opts; they are both found in nf_conntrack > BTF; for example: > > bpftool btf dump file /sys/kernel/btf/nf_conntrack|grep ct_opts > [114754] STRUCT 'bpf_ct_opts' size=12 vlen=5 > > This causes compilation errors as follows: > > CLNG-BPF [test_maps] xdp_synproxy_kern.o > progs/xdp_synproxy_kern.c:83:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] > struct bpf_ct_opts *opts, > ^ > progs/xdp_synproxy_kern.c:89:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] > struct bpf_ct_opts *opts, > ^ > progs/xdp_synproxy_kern.c:397:15: error: use of undeclared identifier 'BPF_F_CURRENT_NETNS'; did you mean 'BPF_F_CURRENT_CPU'? > .netns_id = BPF_F_CURRENT_NETNS, > ^~~~~~~~~~~~~~~~~~~ > BPF_F_CURRENT_CPU > tools/testing/selftests/bpf/tools/include/vmlinux.h:43115:2: note: 'BPF_F_CURRENT_CPU' declared here > BPF_F_CURRENT_CPU = 4294967295, > > While tools/testing/selftests/bpf/config does specify > CONFIG_NF_CONNTRACK=y, it would be good to use this case to show > how we can generate a module header file via split BTF. > > In the selftests Makefile, we define NF_CONNTRACK BTF via VMLINUX_BTF > (thus gaining the path determination logic it uses). If the nf_conntrack > BTF file exists (which means it is built as a module), we run > "bpftool btf dump" to generate module BTF, and if not we simply copy > vmlinux.h to nf_conntrack.h; this allows us to avoid having to pass > a #define or deal with CONFIG variables in the program. > > With these changes the test builds and passes: > > Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED > > Signed-off-by: Alan Maguire <alan.maguire@oracle.com> > --- Why not just define expected types locally (doesn't have to be a full definition)? Adding extra rule and generating header for each potential module seems like a huge overkill. > tools/testing/selftests/bpf/Makefile | 11 +++++++++++ > tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c | 2 +- > 2 files changed, 12 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile > index cb8e552..a5fa636 100644 > --- a/tools/testing/selftests/bpf/Makefile > +++ b/tools/testing/selftests/bpf/Makefile > @@ -141,6 +141,8 @@ VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) > ifeq ($(VMLINUX_BTF),) > $(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)") > endif > +# If nf_conntrack is a module, need BTF for it also > +NF_CONNTRACK_BTF ?= $(shell dirname $(VMLINUX_BTF))/nf_conntrack > > # Define simple and short `make test_progs`, `make test_sysctl`, etc targets > # to build individual tests. > @@ -280,6 +282,14 @@ else > $(Q)cp "$(VMLINUX_H)" $@ > endif > > +$(INCLUDE_DIR)/nf_conntrack.h: $(INCLUDE_DIR)/vmlinux.h > +ifneq ("$(wildcard $(NF_CONNTRACK_BTF))","") > + $(call msg,GEN,,$@) > + $(BPFTOOL) btf dump file $(NF_CONNTRACK_BTF) format c > $@ > +else > + $(Q)cp $(INCLUDE_DIR)/vmlinux.h $@ > +endif > + > $(RESOLVE_BTFIDS): $(HOST_BPFOBJ) | $(HOST_BUILD_DIR)/resolve_btfids \ > $(TOOLSDIR)/bpf/resolve_btfids/main.c \ > $(TOOLSDIR)/lib/rbtree.c \ > @@ -417,6 +427,7 @@ $(TRUNNER_BPF_OBJS): $(TRUNNER_OUTPUT)/%.o: \ > $(TRUNNER_BPF_PROGS_DIR)/%.c \ > $(TRUNNER_BPF_PROGS_DIR)/*.h \ > $$(INCLUDE_DIR)/vmlinux.h \ > + $$(INCLUDE_DIR)/nf_conntrack.h \ > $(wildcard $(BPFDIR)/bpf_*.h) \ > $(wildcard $(BPFDIR)/*.bpf.h) \ > | $(TRUNNER_OUTPUT) $$(BPFOBJ) > diff --git a/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c b/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c > index 9fd62e9..8c5f46e 100644 > --- a/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c > +++ b/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c > @@ -1,7 +1,7 @@ > // SPDX-License-Identifier: LGPL-2.1 OR BSD-2-Clause > /* Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */ > > -#include "vmlinux.h" > +#include "nf_conntrack.h" > > #include <bpf/bpf_helpers.h> > #include <bpf/bpf_endian.h> > -- > 1.8.3.1 >
On 23/06/2022 18:56, Andrii Nakryiko wrote: > On Thu, Jun 23, 2022 at 4:10 AM Alan Maguire <alan.maguire@oracle.com> wrote: >> >> when CONFIG_NF_CONNTRACK=m, vmlinux BTF does not contain >> BPF_F_CURRENT_NETNS or bpf_ct_opts; they are both found in nf_conntrack >> BTF; for example: >> >> bpftool btf dump file /sys/kernel/btf/nf_conntrack|grep ct_opts >> [114754] STRUCT 'bpf_ct_opts' size=12 vlen=5 >> >> This causes compilation errors as follows: >> >> CLNG-BPF [test_maps] xdp_synproxy_kern.o >> progs/xdp_synproxy_kern.c:83:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] >> struct bpf_ct_opts *opts, >> ^ >> progs/xdp_synproxy_kern.c:89:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] >> struct bpf_ct_opts *opts, >> ^ >> progs/xdp_synproxy_kern.c:397:15: error: use of undeclared identifier 'BPF_F_CURRENT_NETNS'; did you mean 'BPF_F_CURRENT_CPU'? >> .netns_id = BPF_F_CURRENT_NETNS, >> ^~~~~~~~~~~~~~~~~~~ >> BPF_F_CURRENT_CPU >> tools/testing/selftests/bpf/tools/include/vmlinux.h:43115:2: note: 'BPF_F_CURRENT_CPU' declared here >> BPF_F_CURRENT_CPU = 4294967295, >> >> While tools/testing/selftests/bpf/config does specify >> CONFIG_NF_CONNTRACK=y, it would be good to use this case to show >> how we can generate a module header file via split BTF. >> >> In the selftests Makefile, we define NF_CONNTRACK BTF via VMLINUX_BTF >> (thus gaining the path determination logic it uses). If the nf_conntrack >> BTF file exists (which means it is built as a module), we run >> "bpftool btf dump" to generate module BTF, and if not we simply copy >> vmlinux.h to nf_conntrack.h; this allows us to avoid having to pass >> a #define or deal with CONFIG variables in the program. >> >> With these changes the test builds and passes: >> >> Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED >> >> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> >> --- > > Why not just define expected types locally (doesn't have to be a full > definition)? Adding extra rule and generating header for each > potential module seems like a huge overkill. > True. I also forgot that if we use vmlinux in the kernel tree as the source for vmlinux BTF, this approach won't work since it assumes it will find nf_conntrack in the same directory. I'll figure out a simpler approach. Thanks for taking a look! Alan
On Fri, Jun 24, 2022 at 2:46 PM Alan Maguire <alan.maguire@oracle.com> wrote: > > On 23/06/2022 18:56, Andrii Nakryiko wrote: > > On Thu, Jun 23, 2022 at 4:10 AM Alan Maguire <alan.maguire@oracle.com> wrote: > >> > >> when CONFIG_NF_CONNTRACK=m, vmlinux BTF does not contain > >> BPF_F_CURRENT_NETNS or bpf_ct_opts; they are both found in nf_conntrack > >> BTF; for example: > >> > >> bpftool btf dump file /sys/kernel/btf/nf_conntrack|grep ct_opts > >> [114754] STRUCT 'bpf_ct_opts' size=12 vlen=5 > >> > >> This causes compilation errors as follows: > >> > >> CLNG-BPF [test_maps] xdp_synproxy_kern.o > >> progs/xdp_synproxy_kern.c:83:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] > >> struct bpf_ct_opts *opts, > >> ^ > >> progs/xdp_synproxy_kern.c:89:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] > >> struct bpf_ct_opts *opts, > >> ^ > >> progs/xdp_synproxy_kern.c:397:15: error: use of undeclared identifier 'BPF_F_CURRENT_NETNS'; did you mean 'BPF_F_CURRENT_CPU'? > >> .netns_id = BPF_F_CURRENT_NETNS, > >> ^~~~~~~~~~~~~~~~~~~ > >> BPF_F_CURRENT_CPU > >> tools/testing/selftests/bpf/tools/include/vmlinux.h:43115:2: note: 'BPF_F_CURRENT_CPU' declared here > >> BPF_F_CURRENT_CPU = 4294967295, > >> > >> While tools/testing/selftests/bpf/config does specify > >> CONFIG_NF_CONNTRACK=y, it would be good to use this case to show > >> how we can generate a module header file via split BTF. > >> > >> In the selftests Makefile, we define NF_CONNTRACK BTF via VMLINUX_BTF > >> (thus gaining the path determination logic it uses). If the nf_conntrack > >> BTF file exists (which means it is built as a module), we run > >> "bpftool btf dump" to generate module BTF, and if not we simply copy > >> vmlinux.h to nf_conntrack.h; this allows us to avoid having to pass > >> a #define or deal with CONFIG variables in the program. > >> > >> With these changes the test builds and passes: > >> > >> Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED > >> > >> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> > >> --- > > > > Why not just define expected types locally (doesn't have to be a full > > definition)? Adding extra rule and generating header for each > > potential module seems like a huge overkill. > > > > True. I also forgot that if we use vmlinux in the kernel tree as the > source for vmlinux BTF, this approach won't work since it assumes it > will find nf_conntrack in the same directory. I'll figure out a simpler > approach. Thanks for taking a look! Just define local minimal local definitions of relevant types with ___local suffix, e.g.: struct nf_conn___local { long unsigned int status; /* and whatever else we are using */ }; Keep in mind that with CO-RE triple underscore suffix is ignored, which can be used to avoid type conflicts > > Alan
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index cb8e552..a5fa636 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -141,6 +141,8 @@ VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) ifeq ($(VMLINUX_BTF),) $(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)") endif +# If nf_conntrack is a module, need BTF for it also +NF_CONNTRACK_BTF ?= $(shell dirname $(VMLINUX_BTF))/nf_conntrack # Define simple and short `make test_progs`, `make test_sysctl`, etc targets # to build individual tests. @@ -280,6 +282,14 @@ else $(Q)cp "$(VMLINUX_H)" $@ endif +$(INCLUDE_DIR)/nf_conntrack.h: $(INCLUDE_DIR)/vmlinux.h +ifneq ("$(wildcard $(NF_CONNTRACK_BTF))","") + $(call msg,GEN,,$@) + $(BPFTOOL) btf dump file $(NF_CONNTRACK_BTF) format c > $@ +else + $(Q)cp $(INCLUDE_DIR)/vmlinux.h $@ +endif + $(RESOLVE_BTFIDS): $(HOST_BPFOBJ) | $(HOST_BUILD_DIR)/resolve_btfids \ $(TOOLSDIR)/bpf/resolve_btfids/main.c \ $(TOOLSDIR)/lib/rbtree.c \ @@ -417,6 +427,7 @@ $(TRUNNER_BPF_OBJS): $(TRUNNER_OUTPUT)/%.o: \ $(TRUNNER_BPF_PROGS_DIR)/%.c \ $(TRUNNER_BPF_PROGS_DIR)/*.h \ $$(INCLUDE_DIR)/vmlinux.h \ + $$(INCLUDE_DIR)/nf_conntrack.h \ $(wildcard $(BPFDIR)/bpf_*.h) \ $(wildcard $(BPFDIR)/*.bpf.h) \ | $(TRUNNER_OUTPUT) $$(BPFOBJ) diff --git a/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c b/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c index 9fd62e9..8c5f46e 100644 --- a/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c +++ b/tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: LGPL-2.1 OR BSD-2-Clause /* Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */ -#include "vmlinux.h" +#include "nf_conntrack.h" #include <bpf/bpf_helpers.h> #include <bpf/bpf_endian.h>
when CONFIG_NF_CONNTRACK=m, vmlinux BTF does not contain BPF_F_CURRENT_NETNS or bpf_ct_opts; they are both found in nf_conntrack BTF; for example: bpftool btf dump file /sys/kernel/btf/nf_conntrack|grep ct_opts [114754] STRUCT 'bpf_ct_opts' size=12 vlen=5 This causes compilation errors as follows: CLNG-BPF [test_maps] xdp_synproxy_kern.o progs/xdp_synproxy_kern.c:83:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] struct bpf_ct_opts *opts, ^ progs/xdp_synproxy_kern.c:89:14: error: declaration of 'struct bpf_ct_opts' will not be visible outside of this function [-Werror,-Wvisibility] struct bpf_ct_opts *opts, ^ progs/xdp_synproxy_kern.c:397:15: error: use of undeclared identifier 'BPF_F_CURRENT_NETNS'; did you mean 'BPF_F_CURRENT_CPU'? .netns_id = BPF_F_CURRENT_NETNS, ^~~~~~~~~~~~~~~~~~~ BPF_F_CURRENT_CPU tools/testing/selftests/bpf/tools/include/vmlinux.h:43115:2: note: 'BPF_F_CURRENT_CPU' declared here BPF_F_CURRENT_CPU = 4294967295, While tools/testing/selftests/bpf/config does specify CONFIG_NF_CONNTRACK=y, it would be good to use this case to show how we can generate a module header file via split BTF. In the selftests Makefile, we define NF_CONNTRACK BTF via VMLINUX_BTF (thus gaining the path determination logic it uses). If the nf_conntrack BTF file exists (which means it is built as a module), we run "bpftool btf dump" to generate module BTF, and if not we simply copy vmlinux.h to nf_conntrack.h; this allows us to avoid having to pass a #define or deal with CONFIG variables in the program. With these changes the test builds and passes: Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Alan Maguire <alan.maguire@oracle.com> --- tools/testing/selftests/bpf/Makefile | 11 +++++++++++ tools/testing/selftests/bpf/progs/xdp_synproxy_kern.c | 2 +- 2 files changed, 12 insertions(+), 1 deletion(-)