* [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section @ 2022-12-17 22:35 Changbin Du 2022-12-17 22:35 ` [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section Changbin Du ` (2 more replies) 0 siblings, 3 replies; 18+ messages in thread From: Changbin Du @ 2022-12-17 22:35 UTC (permalink / raw) To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan Cc: Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest, Changbin Du Display error message for missing ".BTF" section and clean up empty vmlinux.h file. v3: - fix typo and make error message consistent. (Andrii Nakryiko) - split out perf change. v2: - remove vmlinux specific error info. - use builtin target .DELETE_ON_ERROR: to delete empty vmlinux.h Changbin Du (2): libbpf: show error info about missing ".BTF" section bpf: makefiles: do not generate empty vmlinux.h tools/bpf/bpftool/Makefile | 3 +++ tools/lib/bpf/btf.c | 1 + tools/testing/selftests/bpf/Makefile | 3 +++ 3 files changed, 7 insertions(+) -- 2.37.2 ^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-17 22:35 [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section Changbin Du @ 2022-12-17 22:35 ` Changbin Du 2022-12-19 3:45 ` Leo Yan 2022-12-17 22:35 ` [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h Changbin Du 2022-12-21 0:20 ` [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section patchwork-bot+netdevbpf 2 siblings, 1 reply; 18+ messages in thread From: Changbin Du @ 2022-12-17 22:35 UTC (permalink / raw) To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan Cc: Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest, Changbin Du Show the real problem instead of just saying "No such file or directory". Now will print below info: libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory Signed-off-by: Changbin Du <changbin.du@gmail.com> --- tools/lib/bpf/btf.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 71e165b09ed5..dd2badf1a54e 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, err = 0; if (!btf_data) { + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); err = -ENOENT; goto done; } -- 2.37.2 ^ permalink raw reply related [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-17 22:35 ` [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section Changbin Du @ 2022-12-19 3:45 ` Leo Yan 2022-12-20 1:31 ` Changbin Du 0 siblings, 1 reply; 18+ messages in thread From: Leo Yan @ 2022-12-19 3:45 UTC (permalink / raw) To: Changbin Du Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest Hi Changbin, On Sun, Dec 18, 2022 at 06:35:08AM +0800, Changbin Du wrote: > Show the real problem instead of just saying "No such file or directory". > > Now will print below info: > libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux Recently I encountered the same issue, it could be caused by: either missing to install tool pahole or missing to enable kernel configuration CONFIG_DEBUG_INFO_BTF. Could we give explict info for reasoning failure? Like: "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". > Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory This log is confusing when we can find vmlinux file but without BTF section. Consider to use a separate patch to detect vmlinux not found case and print out "No such file or directory"? Thanks, Leo > Signed-off-by: Changbin Du <changbin.du@gmail.com> > --- > tools/lib/bpf/btf.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > index 71e165b09ed5..dd2badf1a54e 100644 > --- a/tools/lib/bpf/btf.c > +++ b/tools/lib/bpf/btf.c > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > err = 0; > > if (!btf_data) { > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > err = -ENOENT; > goto done; > } > -- > 2.37.2 > ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-19 3:45 ` Leo Yan @ 2022-12-20 1:31 ` Changbin Du 2022-12-20 11:34 ` Leo Yan 0 siblings, 1 reply; 18+ messages in thread From: Changbin Du @ 2022-12-20 1:31 UTC (permalink / raw) To: Leo Yan Cc: Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Mon, Dec 19, 2022 at 11:45:08AM +0800, Leo Yan wrote: > Hi Changbin, > > On Sun, Dec 18, 2022 at 06:35:08AM +0800, Changbin Du wrote: > > Show the real problem instead of just saying "No such file or directory". > > > > Now will print below info: > > libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux > > Recently I encountered the same issue, it could be caused by: > either missing to install tool pahole or missing to enable kernel > configuration CONFIG_DEBUG_INFO_BTF. > > Could we give explict info for reasoning failure? Like: > > "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, > please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". > This is vmlinux special information and similar tips are removed from patch V2. libbpf is common for all ELFs. > > Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory > > This log is confusing when we can find vmlinux file but without BTF > section. Consider to use a separate patch to detect vmlinux not > found case and print out "No such file or directory"? > I think it's already there. If the file doesn't exist, open will fail. > Thanks, > Leo > > > Signed-off-by: Changbin Du <changbin.du@gmail.com> > > --- > > tools/lib/bpf/btf.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > > index 71e165b09ed5..dd2badf1a54e 100644 > > --- a/tools/lib/bpf/btf.c > > +++ b/tools/lib/bpf/btf.c > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > err = 0; > > > > if (!btf_data) { > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > err = -ENOENT; > > goto done; > > } > > -- > > 2.37.2 > > -- Cheers, Changbin Du ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-20 1:31 ` Changbin Du @ 2022-12-20 11:34 ` Leo Yan 2022-12-21 0:13 ` Andrii Nakryiko 0 siblings, 1 reply; 18+ messages in thread From: Leo Yan @ 2022-12-20 11:34 UTC (permalink / raw) To: Changbin Du Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Tue, Dec 20, 2022 at 09:31:14AM +0800, Changbin Du wrote: [...] > > > Now will print below info: > > > libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux > > > > Recently I encountered the same issue, it could be caused by: > > either missing to install tool pahole or missing to enable kernel > > configuration CONFIG_DEBUG_INFO_BTF. > > > > Could we give explict info for reasoning failure? Like: > > > > "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, > > please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". > > > This is vmlinux special information and similar tips are removed from > patch V2. libbpf is common for all ELFs. Okay, I see. Sorry for noise. > > > Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory > > > > This log is confusing when we can find vmlinux file but without BTF > > section. Consider to use a separate patch to detect vmlinux not > > found case and print out "No such file or directory"? > > > I think it's already there. If the file doesn't exist, open will fail. [...] > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > err = 0; > > > > > > if (!btf_data) { > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > err = -ENOENT; btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF section, therefore, bpftool dumps error string "No such file or directory". It's confused that actually vmlinux is existed. I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any better choice?) to replace -ENOENT at here, this can avoid bpftool to outputs "No such file or directory" in this case. Thanks, Leo ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-20 11:34 ` Leo Yan @ 2022-12-21 0:13 ` Andrii Nakryiko 2022-12-21 3:55 ` Leo Yan 2023-01-03 15:03 ` Quentin Monnet 0 siblings, 2 replies; 18+ messages in thread From: Andrii Nakryiko @ 2022-12-21 0:13 UTC (permalink / raw) To: Leo Yan, Quentin Monnet Cc: Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Tue, Dec 20, 2022 at 3:34 AM Leo Yan <leo.yan@linaro.org> wrote: > > On Tue, Dec 20, 2022 at 09:31:14AM +0800, Changbin Du wrote: > > [...] > > > > > Now will print below info: > > > > libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux > > > > > > Recently I encountered the same issue, it could be caused by: > > > either missing to install tool pahole or missing to enable kernel > > > configuration CONFIG_DEBUG_INFO_BTF. > > > > > > Could we give explict info for reasoning failure? Like: > > > > > > "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, > > > please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". > > > > > This is vmlinux special information and similar tips are removed from > > patch V2. libbpf is common for all ELFs. > > Okay, I see. Sorry for noise. > > > > > Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory > > > > > > This log is confusing when we can find vmlinux file but without BTF > > > section. Consider to use a separate patch to detect vmlinux not > > > found case and print out "No such file or directory"? > > > > > I think it's already there. If the file doesn't exist, open will fail. > > [...] > > > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > > err = 0; > > > > > > > > if (!btf_data) { > > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > > err = -ENOENT; > > btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > section, therefore, bpftool dumps error string "No such file or > directory". It's confused that actually vmlinux is existed. > > I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > better choice?) to replace -ENOENT at here, this can avoid bpftool to > outputs "No such file or directory" in this case. The only really meaningful error code would be -ESRCH, which strerror() will translate to "No such process", which is also completely confusing. In general, I always found these strerror() messages extremely unhelpful and confusing. I wonder if we should make an effort to actually emit symbolic names of errors instead (literally, "-ENOENT" in this case). This is all tooling for engineers, I find -ENOENT or -ESRCH much more meaningful as an error message, compared to "No such file" seemingly human-readable interpretation. Quenting, what do you think about the above proposal for bpftool? We can have some libbpf helper internally and do it in libbpf error messages as well and just reuse the logic in bpftool, perhaps? Anyways, I've applied this patch set to bpf-next. Thanks. > > Thanks, > Leo ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-21 0:13 ` Andrii Nakryiko @ 2022-12-21 3:55 ` Leo Yan 2022-12-22 18:51 ` Andrii Nakryiko 2022-12-30 12:10 ` Changbin Du 2023-01-03 15:03 ` Quentin Monnet 1 sibling, 2 replies; 18+ messages in thread From: Leo Yan @ 2022-12-21 3:55 UTC (permalink / raw) To: Andrii Nakryiko Cc: Quentin Monnet, Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Tue, Dec 20, 2022 at 04:13:13PM -0800, Andrii Nakryiko wrote: [...] > > > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > > > err = 0; > > > > > > > > > > if (!btf_data) { > > > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > > > err = -ENOENT; > > > > btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > > section, therefore, bpftool dumps error string "No such file or > > directory". It's confused that actually vmlinux is existed. > > > > I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > > better choice?) to replace -ENOENT at here, this can avoid bpftool to > > outputs "No such file or directory" in this case. > > The only really meaningful error code would be -ESRCH, which > strerror() will translate to "No such process", which is also > completely confusing. Or maybe -ENODATA (No data available) is a better choice? Thanks, Leo > In general, I always found these strerror() messages extremely > unhelpful and confusing. I wonder if we should make an effort to > actually emit symbolic names of errors instead (literally, "-ENOENT" > in this case). This is all tooling for engineers, I find -ENOENT or > -ESRCH much more meaningful as an error message, compared to "No such > file" seemingly human-readable interpretation. > > Quenting, what do you think about the above proposal for bpftool? We > can have some libbpf helper internally and do it in libbpf error > messages as well and just reuse the logic in bpftool, perhaps? > > Anyways, I've applied this patch set to bpf-next. Thanks. ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-21 3:55 ` Leo Yan @ 2022-12-22 18:51 ` Andrii Nakryiko 2022-12-30 12:10 ` Changbin Du 1 sibling, 0 replies; 18+ messages in thread From: Andrii Nakryiko @ 2022-12-22 18:51 UTC (permalink / raw) To: Leo Yan Cc: Quentin Monnet, Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Tue, Dec 20, 2022 at 7:55 PM Leo Yan <leo.yan@linaro.org> wrote: > > On Tue, Dec 20, 2022 at 04:13:13PM -0800, Andrii Nakryiko wrote: > > [...] > > > > > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > > > > err = 0; > > > > > > > > > > > > if (!btf_data) { > > > > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > > > > err = -ENOENT; > > > > > > btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > > > section, therefore, bpftool dumps error string "No such file or > > > directory". It's confused that actually vmlinux is existed. > > > > > > I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > > > better choice?) to replace -ENOENT at here, this can avoid bpftool to > > > outputs "No such file or directory" in this case. > > > > The only really meaningful error code would be -ESRCH, which > > strerror() will translate to "No such process", which is also > > completely confusing. > > Or maybe -ENODATA (No data available) is a better choice? -ENODATA sounds good to me, yep. > > Thanks, > Leo > > > In general, I always found these strerror() messages extremely > > unhelpful and confusing. I wonder if we should make an effort to > > actually emit symbolic names of errors instead (literally, "-ENOENT" > > in this case). This is all tooling for engineers, I find -ENOENT or > > -ESRCH much more meaningful as an error message, compared to "No such > > file" seemingly human-readable interpretation. > > > > Quenting, what do you think about the above proposal for bpftool? We > > can have some libbpf helper internally and do it in libbpf error > > messages as well and just reuse the logic in bpftool, perhaps? > > > > Anyways, I've applied this patch set to bpf-next. Thanks. ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-21 3:55 ` Leo Yan 2022-12-22 18:51 ` Andrii Nakryiko @ 2022-12-30 12:10 ` Changbin Du 2022-12-30 12:28 ` Leo Yan 1 sibling, 1 reply; 18+ messages in thread From: Changbin Du @ 2022-12-30 12:10 UTC (permalink / raw) To: Leo Yan Cc: Andrii Nakryiko, Quentin Monnet, Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Wed, Dec 21, 2022 at 11:55:24AM +0800, Leo Yan wrote: > On Tue, Dec 20, 2022 at 04:13:13PM -0800, Andrii Nakryiko wrote: > > [...] > > > > > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > > > > err = 0; > > > > > > > > > > > > if (!btf_data) { > > > > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > > > > err = -ENOENT; > > > > > > btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > > > section, therefore, bpftool dumps error string "No such file or > > > directory". It's confused that actually vmlinux is existed. > > > > > > I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > > > better choice?) to replace -ENOENT at here, this can avoid bpftool to > > > outputs "No such file or directory" in this case. > > > > The only really meaningful error code would be -ESRCH, which > > strerror() will translate to "No such process", which is also > > completely confusing. > > Or maybe -ENODATA (No data available) is a better choice? > > Thanks, > Leo > Yan, will you have a patch for this suggestion? [snip] -- Cheers, Changbin Du ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-30 12:10 ` Changbin Du @ 2022-12-30 12:28 ` Leo Yan 0 siblings, 0 replies; 18+ messages in thread From: Leo Yan @ 2022-12-30 12:28 UTC (permalink / raw) To: Changbin Du Cc: Andrii Nakryiko, Quentin Monnet, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Fri, Dec 30, 2022 at 08:10:20PM +0800, Changbin Du wrote: > On Wed, Dec 21, 2022 at 11:55:24AM +0800, Leo Yan wrote: > > On Tue, Dec 20, 2022 at 04:13:13PM -0800, Andrii Nakryiko wrote: > > > > [...] > > > > > > > > > @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > > > > > > > err = 0; > > > > > > > > > > > > > > if (!btf_data) { > > > > > > > + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > > > > > > > err = -ENOENT; > > > > > > > > btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > > > > section, therefore, bpftool dumps error string "No such file or > > > > directory". It's confused that actually vmlinux is existed. > > > > > > > > I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > > > > better choice?) to replace -ENOENT at here, this can avoid bpftool to > > > > outputs "No such file or directory" in this case. > > > > > > The only really meaningful error code would be -ESRCH, which > > > strerror() will translate to "No such process", which is also > > > completely confusing. > > > > Or maybe -ENODATA (No data available) is a better choice? > > > > Thanks, > > Leo > > > Yan, will you have a patch for this suggestion? You are welcome to send a patch, otherwise, I can cook one. Thanks, Leo ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2022-12-21 0:13 ` Andrii Nakryiko 2022-12-21 3:55 ` Leo Yan @ 2023-01-03 15:03 ` Quentin Monnet 2023-01-03 23:46 ` Andrii Nakryiko 1 sibling, 1 reply; 18+ messages in thread From: Quentin Monnet @ 2023-01-03 15:03 UTC (permalink / raw) To: Andrii Nakryiko, Leo Yan Cc: Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest 2022-12-20 16:13 UTC-0800 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com> > On Tue, Dec 20, 2022 at 3:34 AM Leo Yan <leo.yan@linaro.org> wrote: >> >> On Tue, Dec 20, 2022 at 09:31:14AM +0800, Changbin Du wrote: >> >> [...] >> >>>>> Now will print below info: >>>>> libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux >>>> >>>> Recently I encountered the same issue, it could be caused by: >>>> either missing to install tool pahole or missing to enable kernel >>>> configuration CONFIG_DEBUG_INFO_BTF. >>>> >>>> Could we give explict info for reasoning failure? Like: >>>> >>>> "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, >>>> please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". >>>> >>> This is vmlinux special information and similar tips are removed from >>> patch V2. libbpf is common for all ELFs. >> >> Okay, I see. Sorry for noise. >> >>>>> Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory >>>> >>>> This log is confusing when we can find vmlinux file but without BTF >>>> section. Consider to use a separate patch to detect vmlinux not >>>> found case and print out "No such file or directory"? >>>> >>> I think it's already there. If the file doesn't exist, open will fail. >> >> [...] >> >>>>> @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, >>>>> err = 0; >>>>> >>>>> if (!btf_data) { >>>>> + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); >>>>> err = -ENOENT; >> >> btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF >> section, therefore, bpftool dumps error string "No such file or >> directory". It's confused that actually vmlinux is existed. >> >> I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any >> better choice?) to replace -ENOENT at here, this can avoid bpftool to >> outputs "No such file or directory" in this case. > > The only really meaningful error code would be -ESRCH, which > strerror() will translate to "No such process", which is also > completely confusing. > > In general, I always found these strerror() messages extremely > unhelpful and confusing. I wonder if we should make an effort to > actually emit symbolic names of errors instead (literally, "-ENOENT" > in this case). This is all tooling for engineers, I find -ENOENT or > -ESRCH much more meaningful as an error message, compared to "No such > file" seemingly human-readable interpretation. > > Quenting, what do you think about the above proposal for bpftool? We > can have some libbpf helper internally and do it in libbpf error > messages as well and just reuse the logic in bpftool, perhaps? Apologies for the delay. What you're proposing is to replace all messages currently looking like this: $ bpftool prog Error: can't get next program: Operation not permitted by: $ bpftool prog Error: can't get next program: -EPERM Do I understand correctly? I think the strerror() messages are helpful in some occasions (they _are_ more human-friendly to many users), but it's also true that they're not always precise. With bpftool, "Invalid argument" is a classic when the program doesn't load, and may lead to confusion with the args passed to bpftool on the command line. Then there are the other corner cases like the one discussed in this thread. So, why not. If we do change, yeah I'd rather have as much of this handling in libbpf itself, and then adjust bpftool to handle the remaining cases, for consistency. Quentin ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2023-01-03 15:03 ` Quentin Monnet @ 2023-01-03 23:46 ` Andrii Nakryiko 2023-01-05 14:57 ` Quentin Monnet 0 siblings, 1 reply; 18+ messages in thread From: Andrii Nakryiko @ 2023-01-03 23:46 UTC (permalink / raw) To: Quentin Monnet Cc: Leo Yan, Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Tue, Jan 3, 2023 at 7:03 AM Quentin Monnet <quentin@isovalent.com> wrote: > > 2022-12-20 16:13 UTC-0800 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com> > > On Tue, Dec 20, 2022 at 3:34 AM Leo Yan <leo.yan@linaro.org> wrote: > >> > >> On Tue, Dec 20, 2022 at 09:31:14AM +0800, Changbin Du wrote: > >> > >> [...] > >> > >>>>> Now will print below info: > >>>>> libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux > >>>> > >>>> Recently I encountered the same issue, it could be caused by: > >>>> either missing to install tool pahole or missing to enable kernel > >>>> configuration CONFIG_DEBUG_INFO_BTF. > >>>> > >>>> Could we give explict info for reasoning failure? Like: > >>>> > >>>> "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, > >>>> please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". > >>>> > >>> This is vmlinux special information and similar tips are removed from > >>> patch V2. libbpf is common for all ELFs. > >> > >> Okay, I see. Sorry for noise. > >> > >>>>> Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory > >>>> > >>>> This log is confusing when we can find vmlinux file but without BTF > >>>> section. Consider to use a separate patch to detect vmlinux not > >>>> found case and print out "No such file or directory"? > >>>> > >>> I think it's already there. If the file doesn't exist, open will fail. > >> > >> [...] > >> > >>>>> @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, > >>>>> err = 0; > >>>>> > >>>>> if (!btf_data) { > >>>>> + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); > >>>>> err = -ENOENT; > >> > >> btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF > >> section, therefore, bpftool dumps error string "No such file or > >> directory". It's confused that actually vmlinux is existed. > >> > >> I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any > >> better choice?) to replace -ENOENT at here, this can avoid bpftool to > >> outputs "No such file or directory" in this case. > > > > The only really meaningful error code would be -ESRCH, which > > strerror() will translate to "No such process", which is also > > completely confusing. > > > > In general, I always found these strerror() messages extremely > > unhelpful and confusing. I wonder if we should make an effort to > > actually emit symbolic names of errors instead (literally, "-ENOENT" > > in this case). This is all tooling for engineers, I find -ENOENT or > > -ESRCH much more meaningful as an error message, compared to "No such > > file" seemingly human-readable interpretation. > > > > Quenting, what do you think about the above proposal for bpftool? We > > can have some libbpf helper internally and do it in libbpf error > > messages as well and just reuse the logic in bpftool, perhaps? > > Apologies for the delay. > What you're proposing is to replace all messages currently looking like > this: > > $ bpftool prog > Error: can't get next program: Operation not permitted > > by: > > $ bpftool prog > Error: can't get next program: -EPERM > > Do I understand correctly? yep, that's what I had in mind > > I think the strerror() messages are helpful in some occasions (they > _are_ more human-friendly to many users), but it's also true that > they're not always precise. With bpftool, "Invalid argument" is a > classic when the program doesn't load, and may lead to confusion with > the args passed to bpftool on the command line. Then there are the other > corner cases like the one discussed in this thread. So, why not. maybe the right approach would be to have both symbolic error name and its human-readable representation, so for example above Error: can't get next program: [-EPERM] Operation not permitted or something like that? And if error value is unknown, just keep it as integer: "[-5555]" ? > > If we do change, yeah I'd rather have as much of this handling in libbpf > itself, and then adjust bpftool to handle the remaining cases, for > consistency. we can teach libbpf_strerror_r() to do this and if bpftool is going to use it consistently then it would get the benefit automatically > > Quentin ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section 2023-01-03 23:46 ` Andrii Nakryiko @ 2023-01-05 14:57 ` Quentin Monnet 0 siblings, 0 replies; 18+ messages in thread From: Quentin Monnet @ 2023-01-05 14:57 UTC (permalink / raw) To: Andrii Nakryiko Cc: Leo Yan, Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest 2023-01-03 15:46 UTC-0800 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com> > On Tue, Jan 3, 2023 at 7:03 AM Quentin Monnet <quentin@isovalent.com> wrote: >> >> 2022-12-20 16:13 UTC-0800 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com> >>> On Tue, Dec 20, 2022 at 3:34 AM Leo Yan <leo.yan@linaro.org> wrote: >>>> >>>> On Tue, Dec 20, 2022 at 09:31:14AM +0800, Changbin Du wrote: >>>> >>>> [...] >>>> >>>>>>> Now will print below info: >>>>>>> libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux >>>>>> >>>>>> Recently I encountered the same issue, it could be caused by: >>>>>> either missing to install tool pahole or missing to enable kernel >>>>>> configuration CONFIG_DEBUG_INFO_BTF. >>>>>> >>>>>> Could we give explict info for reasoning failure? Like: >>>>>> >>>>>> "libbpf: failed to find '.BTF' ELF section in /home/changbin/work/linux/vmlinux, >>>>>> please install pahole and enable CONFIG_DEBUG_INFO_BTF=y for kernel building". >>>>>> >>>>> This is vmlinux special information and similar tips are removed from >>>>> patch V2. libbpf is common for all ELFs. >>>> >>>> Okay, I see. Sorry for noise. >>>> >>>>>>> Error: failed to load BTF from /home/changbin/work/linux/vmlinux: No such file or directory >>>>>> >>>>>> This log is confusing when we can find vmlinux file but without BTF >>>>>> section. Consider to use a separate patch to detect vmlinux not >>>>>> found case and print out "No such file or directory"? >>>>>> >>>>> I think it's already there. If the file doesn't exist, open will fail. >>>> >>>> [...] >>>> >>>>>>> @@ -990,6 +990,7 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, >>>>>>> err = 0; >>>>>>> >>>>>>> if (!btf_data) { >>>>>>> + pr_warn("failed to find '%s' ELF section in %s\n", BTF_ELF_SEC, path); >>>>>>> err = -ENOENT; >>>> >>>> btf_parse_elf() returns -ENOENT when ELF file doesn't contain BTF >>>> section, therefore, bpftool dumps error string "No such file or >>>> directory". It's confused that actually vmlinux is existed. >>>> >>>> I am wondering if we can use error -LIBBPF_ERRNO__FORMAT (or any >>>> better choice?) to replace -ENOENT at here, this can avoid bpftool to >>>> outputs "No such file or directory" in this case. >>> >>> The only really meaningful error code would be -ESRCH, which >>> strerror() will translate to "No such process", which is also >>> completely confusing. >>> >>> In general, I always found these strerror() messages extremely >>> unhelpful and confusing. I wonder if we should make an effort to >>> actually emit symbolic names of errors instead (literally, "-ENOENT" >>> in this case). This is all tooling for engineers, I find -ENOENT or >>> -ESRCH much more meaningful as an error message, compared to "No such >>> file" seemingly human-readable interpretation. >>> >>> Quenting, what do you think about the above proposal for bpftool? We >>> can have some libbpf helper internally and do it in libbpf error >>> messages as well and just reuse the logic in bpftool, perhaps? >> >> Apologies for the delay. >> What you're proposing is to replace all messages currently looking like >> this: >> >> $ bpftool prog >> Error: can't get next program: Operation not permitted >> >> by: >> >> $ bpftool prog >> Error: can't get next program: -EPERM >> >> Do I understand correctly? > > yep, that's what I had in mind > >> >> I think the strerror() messages are helpful in some occasions (they >> _are_ more human-friendly to many users), but it's also true that >> they're not always precise. With bpftool, "Invalid argument" is a >> classic when the program doesn't load, and may lead to confusion with >> the args passed to bpftool on the command line. Then there are the other >> corner cases like the one discussed in this thread. So, why not. > > maybe the right approach would be to have both symbolic error name and > its human-readable representation, so for example above > > Error: can't get next program: [-EPERM] Operation not permitted > > or something like that? And if error value is unknown, just keep it as > integer: "[-5555]" ? That would be great, we'd have both the error name for savvy users and the (more or less accurate) interpretation for others. >> If we do change, yeah I'd rather have as much of this handling in libbpf >> itself, and then adjust bpftool to handle the remaining cases, for >> consistency. > > we can teach libbpf_strerror_r() to do this and if bpftool is going to > use it consistently then it would get the benefit automatically Sounds good to me. ^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h 2022-12-17 22:35 [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section Changbin Du 2022-12-17 22:35 ` [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section Changbin Du @ 2022-12-17 22:35 ` Changbin Du 2022-12-19 3:59 ` Leo Yan 2022-12-20 15:38 ` Quentin Monnet 2022-12-21 0:20 ` [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section patchwork-bot+netdevbpf 2 siblings, 2 replies; 18+ messages in thread From: Changbin Du @ 2022-12-17 22:35 UTC (permalink / raw) To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan Cc: Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest, Changbin Du Remove the empty vmlinux.h if bpftool failed to dump btf info. The empty vmlinux.h can hide real error when reading output of make. This is done by adding .DELETE_ON_ERROR special target in related makefiles. Signed-off-by: Changbin Du <changbin.du@gmail.com> --- tools/bpf/bpftool/Makefile | 3 +++ tools/testing/selftests/bpf/Makefile | 3 +++ 2 files changed, 6 insertions(+) diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index 787b857d3fb5..313fd1b09189 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -289,3 +289,6 @@ FORCE: .PHONY: all FORCE bootstrap clean install-bin install uninstall .PHONY: doc doc-clean doc-install doc-uninstall .DEFAULT_GOAL := all + +# Delete partially updated (corrupted) files on error +.DELETE_ON_ERROR: diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index c22c43bbee19..205e8c3c346a 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -626,3 +626,6 @@ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ liburandom_read.so) .PHONY: docs docs-clean + +# Delete partially updated (corrupted) files on error +.DELETE_ON_ERROR: -- 2.37.2 ^ permalink raw reply related [flat|nested] 18+ messages in thread
* Re: [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h 2022-12-17 22:35 ` [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h Changbin Du @ 2022-12-19 3:59 ` Leo Yan 2022-12-20 1:26 ` Changbin Du 2022-12-20 15:38 ` Quentin Monnet 1 sibling, 1 reply; 18+ messages in thread From: Leo Yan @ 2022-12-19 3:59 UTC (permalink / raw) To: Changbin Du Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Sun, Dec 18, 2022 at 06:35:09AM +0800, Changbin Du wrote: > Remove the empty vmlinux.h if bpftool failed to dump btf info. > The empty vmlinux.h can hide real error when reading output > of make. > > This is done by adding .DELETE_ON_ERROR special target in related > makefiles. We need to handle the same case for perf building, its makefile linux/tools/perf/Makefile.perf also uses bpftool to generate vmlinux.h, see: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/Makefile.perf#n1067 Please consider to use a separate patch to add the same change in Makefile.perf? Thanks, Leo > Signed-off-by: Changbin Du <changbin.du@gmail.com> > --- > tools/bpf/bpftool/Makefile | 3 +++ > tools/testing/selftests/bpf/Makefile | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile > index 787b857d3fb5..313fd1b09189 100644 > --- a/tools/bpf/bpftool/Makefile > +++ b/tools/bpf/bpftool/Makefile > @@ -289,3 +289,6 @@ FORCE: > .PHONY: all FORCE bootstrap clean install-bin install uninstall > .PHONY: doc doc-clean doc-install doc-uninstall > .DEFAULT_GOAL := all > + > +# Delete partially updated (corrupted) files on error > +.DELETE_ON_ERROR: > diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile > index c22c43bbee19..205e8c3c346a 100644 > --- a/tools/testing/selftests/bpf/Makefile > +++ b/tools/testing/selftests/bpf/Makefile > @@ -626,3 +626,6 @@ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ > liburandom_read.so) > > .PHONY: docs docs-clean > + > +# Delete partially updated (corrupted) files on error > +.DELETE_ON_ERROR: > -- > 2.37.2 > ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h 2022-12-19 3:59 ` Leo Yan @ 2022-12-20 1:26 ` Changbin Du 0 siblings, 0 replies; 18+ messages in thread From: Changbin Du @ 2022-12-20 1:26 UTC (permalink / raw) To: Leo Yan Cc: Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Quentin Monnet, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan, Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest On Mon, Dec 19, 2022 at 11:59:38AM +0800, Leo Yan wrote: > On Sun, Dec 18, 2022 at 06:35:09AM +0800, Changbin Du wrote: > > Remove the empty vmlinux.h if bpftool failed to dump btf info. > > The empty vmlinux.h can hide real error when reading output > > of make. > > > > This is done by adding .DELETE_ON_ERROR special target in related > > makefiles. > > We need to handle the same case for perf building, its makefile > linux/tools/perf/Makefile.perf also uses bpftool to generate > vmlinux.h, see: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/perf/Makefile.perf#n1067 > > Please consider to use a separate patch to add the same change in > Makefile.perf? > It's alreay there. https://lore.kernel.org/lkml/20221217225151.90387-1-changbin.du@gmail.com/T/ > Thanks, > Leo > > > Signed-off-by: Changbin Du <changbin.du@gmail.com> > > --- > > tools/bpf/bpftool/Makefile | 3 +++ > > tools/testing/selftests/bpf/Makefile | 3 +++ > > 2 files changed, 6 insertions(+) > > > > diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile > > index 787b857d3fb5..313fd1b09189 100644 > > --- a/tools/bpf/bpftool/Makefile > > +++ b/tools/bpf/bpftool/Makefile > > @@ -289,3 +289,6 @@ FORCE: > > .PHONY: all FORCE bootstrap clean install-bin install uninstall > > .PHONY: doc doc-clean doc-install doc-uninstall > > .DEFAULT_GOAL := all > > + > > +# Delete partially updated (corrupted) files on error > > +.DELETE_ON_ERROR: > > diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile > > index c22c43bbee19..205e8c3c346a 100644 > > --- a/tools/testing/selftests/bpf/Makefile > > +++ b/tools/testing/selftests/bpf/Makefile > > @@ -626,3 +626,6 @@ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ > > liburandom_read.so) > > > > .PHONY: docs docs-clean > > + > > +# Delete partially updated (corrupted) files on error > > +.DELETE_ON_ERROR: > > -- > > 2.37.2 > > -- Cheers, Changbin Du ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h 2022-12-17 22:35 ` [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h Changbin Du 2022-12-19 3:59 ` Leo Yan @ 2022-12-20 15:38 ` Quentin Monnet 1 sibling, 0 replies; 18+ messages in thread From: Quentin Monnet @ 2022-12-20 15:38 UTC (permalink / raw) To: Changbin Du, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Shuah Khan Cc: Martin KaFai Lau, Song Liu, Yonghong Song, John Fastabend, KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, bpf, linux-kernel, Mark Rutland, Alexander Shishkin, Namhyung Kim, Mykola Lysenko, linux-perf-users, linux-kselftest 2022-12-18 06:35 UTC+0800 ~ Changbin Du <changbin.du@gmail.com> > Remove the empty vmlinux.h if bpftool failed to dump btf info. > The empty vmlinux.h can hide real error when reading output > of make. > > This is done by adding .DELETE_ON_ERROR special target in related > makefiles. > > Signed-off-by: Changbin Du <changbin.du@gmail.com> > --- > tools/bpf/bpftool/Makefile | 3 +++ > tools/testing/selftests/bpf/Makefile | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile > index 787b857d3fb5..313fd1b09189 100644 > --- a/tools/bpf/bpftool/Makefile > +++ b/tools/bpf/bpftool/Makefile > @@ -289,3 +289,6 @@ FORCE: > .PHONY: all FORCE bootstrap clean install-bin install uninstall > .PHONY: doc doc-clean doc-install doc-uninstall > .DEFAULT_GOAL := all > + > +# Delete partially updated (corrupted) files on error > +.DELETE_ON_ERROR: Acked-by: Quentin Monnet <quentin@isovalent.com> Thanks! ^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section 2022-12-17 22:35 [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section Changbin Du 2022-12-17 22:35 ` [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section Changbin Du 2022-12-17 22:35 ` [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h Changbin Du @ 2022-12-21 0:20 ` patchwork-bot+netdevbpf 2 siblings, 0 replies; 18+ messages in thread From: patchwork-bot+netdevbpf @ 2022-12-21 0:20 UTC (permalink / raw) To: Changbin Du Cc: ast, daniel, andrii, quentin, peterz, mingo, acme, shuah, martin.lau, song, yhs, john.fastabend, kpsingh, sdf, haoluo, jolsa, bpf, linux-kernel, mark.rutland, alexander.shishkin, namhyung, mykolal, linux-perf-users, linux-kselftest Hello: This series was applied to bpf/bpf-next.git (master) by Andrii Nakryiko <andrii@kernel.org>: On Sun, 18 Dec 2022 06:35:07 +0800 you wrote: > Display error message for missing ".BTF" section and clean up empty > vmlinux.h file. > > v3: > - fix typo and make error message consistent. (Andrii Nakryiko) > - split out perf change. > v2: > - remove vmlinux specific error info. > - use builtin target .DELETE_ON_ERROR: to delete empty vmlinux.h > > [...] Here is the summary with links: - [v3,1/2] libbpf: show error info about missing ".BTF" section https://git.kernel.org/bpf/bpf-next/c/e6b4e1d759d3 - [v3,2/2] bpf: makefiles: do not generate empty vmlinux.h https://git.kernel.org/bpf/bpf-next/c/e7f0d5cdd023 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html ^ permalink raw reply [flat|nested] 18+ messages in thread
end of thread, other threads:[~2023-01-05 14:58 UTC | newest] Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-12-17 22:35 [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section Changbin Du 2022-12-17 22:35 ` [PATCH v3 1/2] libbpf: show error info about missing ".BTF" section Changbin Du 2022-12-19 3:45 ` Leo Yan 2022-12-20 1:31 ` Changbin Du 2022-12-20 11:34 ` Leo Yan 2022-12-21 0:13 ` Andrii Nakryiko 2022-12-21 3:55 ` Leo Yan 2022-12-22 18:51 ` Andrii Nakryiko 2022-12-30 12:10 ` Changbin Du 2022-12-30 12:28 ` Leo Yan 2023-01-03 15:03 ` Quentin Monnet 2023-01-03 23:46 ` Andrii Nakryiko 2023-01-05 14:57 ` Quentin Monnet 2022-12-17 22:35 ` [PATCH v3 2/2] bpf: makefiles: do not generate empty vmlinux.h Changbin Du 2022-12-19 3:59 ` Leo Yan 2022-12-20 1:26 ` Changbin Du 2022-12-20 15:38 ` Quentin Monnet 2022-12-21 0:20 ` [PATCH v3 0/2] bpftool: improve error handing for missing .BTF section patchwork-bot+netdevbpf
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