From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5AE7C8F58 for ; Fri, 12 Jul 2024 14:19:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720793998; cv=none; b=CMZw5uUzmZizb9ivwL1ZNK0cCXgmSw1NxdOwr00k2Vyqa0zJrfyq0g0R8MDzf8vTRp9TmNxrI1bmPrgYzqBpJNUTLIVF+Ri9mhIBq1FIXQnABrMkhGgxlA+3azZVTQpnNkWbNTe0bIlyAZzSvqpCEeE6MBfUxbf1c+8P2K4AW/w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720793998; c=relaxed/simple; bh=i6hRnEj3EyRcoUHZcX5Xr/RQfO3DDJik760VoHmXiio=; h=Message-ID:Subject:From:To:Cc:In-Reply-To:References:Content-Type: MIME-Version:Date; b=eIowdigfuiw94hGI/0434YeUlvNKvQxoHfkFDyfWqAc0nvDOzVQp9KhDH+AhZNsB+39xum4QuYuaEZGDaBPZBwtvR72h7WZGcjKEYOds361iynVuUFC5CL6doj831EOuHWM30A+UO1IdgyjK+8EJVICPT/qKZUeCXi2hdqEOh2k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ksmJ0qGd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ksmJ0qGd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7BE2C32782; Fri, 12 Jul 2024 14:19:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720793997; bh=i6hRnEj3EyRcoUHZcX5Xr/RQfO3DDJik760VoHmXiio=; h=Subject:From:To:Cc:In-Reply-To:References:Date:From; b=ksmJ0qGdix+KDtDC+llkNmC8zDF30cCNRIzw7F/OyZVikfualrwxPZDUUUZhEnGsy XdLKyjqLThCw0KpaVl7kP5Hy+X1sHQK+TB0ceu/VlUyBW0cFqz4iyF8tJtKABfk9sf EaFZhZkcmOidlRTjOONoWybykZhVijc/3RbtXkxUBI445uAy3BXFE4XQ9Iwin+HDzi xyimeiJIdJa2HPcJzkBgPBAaYbVvKAO/eRcd96TRR7SWR+f6NIotK8XY+0789o7zRF kSNDglRS2089BuBYrAUcWWdCjM867IPwPzuy/Ih9iz+z3M4HL2z2Aa+gYJb/DYADht PdE+5XTds6oIg== Message-ID: <83163d7e8162988e5235cca5d79ef3dba2d54565.camel@kernel.org> Subject: Re: [PATCH bpf-next 2/2] libbpf: handle ENOTSUPP in libbpf_strerror_r From: Geliang Tang To: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa Cc: Geliang Tang , bpf@vger.kernel.org In-Reply-To: <2437275bb988da5c187b4d0223e5c0c9843fdc76.1720778831.git.tanggeliang@kylinos.cn> References: <2437275bb988da5c187b4d0223e5c0c9843fdc76.1720778831.git.tanggeliang@kylinos.cn> Autocrypt: addr=geliang@kernel.org; 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charset="UTF-8" Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Fri, 12 Jul 2024 22:10:13 +0800 User-Agent: Evolution 3.52.0-1build2 Content-Transfer-Encoding: 8bit On Fri, 2024-07-12 at 18:14 +0800, Geliang Tang wrote: > From: Geliang Tang > > The errno 95 (ENOTSUP or EOPNOTSUPP) can be recognized by > strerror_r(), > but 524 (ENOTSUPP) can't: > >  prog 'basic_alloc3': BPF program load failed: Operation not > supported >  prog 'basic_alloc3': failed to load: -95 >  failed to load object 'verifier_arena' >  FAIL:unexpected_load_failure unexpected error: -95 (errno 95) > >  prog 'inner_map': BPF program load failed: unknown error (-524) >  prog 'inner_map': failed to load: -524 >  failed to load object 'bloom_filter_map' >  failed to load BPF skeleton 'bloom_filter_map': -524 >  FAIL:bloom_filter_map__open_and_load unexpected error: -524 > > This patch fixes this by handling ENOTSUPP in libbpf_strerror_r(). > With > this change, the new error string looks like: > >  prog 'inner_map': BPF program load failed: Operation not supported > (-524) > > Signed-off-by: Geliang Tang > --- >  tools/lib/bpf/str_error.c | 11 +++++++---- >  tools/lib/bpf/str_error.h |  4 ++++ >  2 files changed, 11 insertions(+), 4 deletions(-) > > diff --git a/tools/lib/bpf/str_error.c b/tools/lib/bpf/str_error.c > index 5e6a1e27ddf9..10597d5124cd 100644 > --- a/tools/lib/bpf/str_error.c > +++ b/tools/lib/bpf/str_error.c > @@ -23,10 +23,13 @@ char *libbpf_strerror_r(int err, char *dst, int > len) >   if (ret == -1) >   ret = errno; >   if (ret) { > - if (ret == EINVAL) > - /* strerror_r() doesn't recognize this > specific error */ > - snprintf(dst, len, "unknown error (%d)", err > < 0 ? err : -err); > - else > + if (ret == EINVAL) { > + if (err == ENOTSUPP) Shouldn't use "err" directly here, should use "err < 0 ? -err : err" instead. I prefer to add an unsigned variable "no" in v2: unsigned int no = err < 0 ? -err : err; And use "switch-case" for future expansion: switch (no) { case ENOTSUPP: > + snprintf(dst, len, "Operation not > supported (%d)", -err); No need to use "Operation not supported (-524)" here, just "Operation not supported" is better. snprintf(dst, len, "Operation not supported"); > + else > + /* strerror_r() doesn't recognize > this specific error */ > + snprintf(dst, len, "unknown error > (%d)", err < 0 ? err : -err); Then here: snprintf(dst, len, "unknown error (-%u)", no); Changes Requested. Will send a v2 soon. Thanks, -Geliang > + } else >   snprintf(dst, len, "ERROR: > strerror_r(%d)=%d", err, ret); >   } >   return dst; > diff --git a/tools/lib/bpf/str_error.h b/tools/lib/bpf/str_error.h > index 626d7ffb03d6..c41f6ba133cf 100644 > --- a/tools/lib/bpf/str_error.h > +++ b/tools/lib/bpf/str_error.h > @@ -4,6 +4,10 @@ >   >  #define STRERR_BUFSIZE  128 >   > +#ifndef ENOTSUPP > +#define ENOTSUPP 524 > +#endif > + >  char *libbpf_strerror_r(int err, char *dst, int len); >   >  #endif /* __LIBBPF_STR_ERROR_H */