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 D1C4336403F; Wed, 17 Dec 2025 15:27:47 +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=1765985268; cv=none; b=cQ5goYwkxGzCE00kkJRd87rgO4bYHSaREr/yxyrQEyt+Tr84FI9ishVMX+0EFpuqY5wMkuISfiLTlk9ptL2REvxdYVGpw5ECSz5pK0wyuNsT63ovRRQcz/9o0DG06uciLXCpvTc0zikxPQHB9FjhMhH06PiGpHS0c+ynSa0/4RE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765985268; c=relaxed/simple; bh=B8wA+8nfD+gltTXk/Kl0y8cBQSP5PKZ/u7nH/ieM6uU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gQT6O++b1f09z8G5kt9PNvVAl8XZ9SHxL8Jm5hXUvuO8NlFgdWgAzq5+ZqqA5lGxTUAoY4QEitJgtBo6HvUp04YCqZzoXm/S/QHhab2nQy7pjPZ1yncxw2RJImgjFeozUElDwquCSb5DxaAR9RGaTrDjEkSguloYLkuT1fdad3g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CD8tcRaZ; 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="CD8tcRaZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DC0CC4CEF5; Wed, 17 Dec 2025 15:27:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765985267; bh=B8wA+8nfD+gltTXk/Kl0y8cBQSP5PKZ/u7nH/ieM6uU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CD8tcRaZgHlUZF5SfMhTsyE+fiaOmfBD1Bl5dtKpnhaIcJNVcoolgoSFLEc1EMr9O qmeH7Ey5cWSMqqZ5ip8X7PwSQ1efS3pBDL2oTu86GKObMKdBp9ZvmHdGiY93bJdTAB +dXg2FYxbtACH7i0d45GLSnUDqs1dOizZAdYFb0vlxEbQ7Z+ms9vDbRpK+TargW1oQ olLg+z5sy1/fvpMYfLRsUTd4edWCIvbSlGfDJfMwrkeIPVSdNbEislQIlKBb6NHSZ0 co8XY8Zmd3r7V9NamQOGONCCBgblDDvZ6dmVKzlRJ+chwY5UigJQKAzLqPuAFHrkwJ cdeBrkU6cMNgA== Date: Wed, 17 Dec 2025 07:27:45 -0800 From: Namhyung Kim To: Ian Rogers Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Adrian Hunter , James Clark , Stephen Brennan , Haibo Xu , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] perf symbol: Fix ENOENT case for filename__read_build_id Message-ID: References: <20251207022345.909535-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20251207022345.909535-1-irogers@google.com> Hi Ian, On Sat, Dec 06, 2025 at 06:23:45PM -0800, Ian Rogers wrote: > Some callers of filename__read_build_id assume the error value must be > -1, fix by making them handle all < 0 values. > > If is_regular_file fails in filename__read_build_id then it could be > the file is missing (ENOENT) and it would be wrong to return > -EWOULDBLOCK in that case. Fix the logic so -EWOULDBLOCK is only > reported if other errors with stat haven't occurred. > > Fixes: 834ebb5678d7 ("perf tools: Don't read build-ids from non-regular files") > Signed-off-by: Ian Rogers > --- > Note, a shorter version of this patch appeared in a series > cleaning/refactoring the build id reading code: > https://lore.kernel.org/lkml/20251201205509.195451-11-irogers@google.com/ > It is sent without the refactor for the sake of fixing the bug in an > earlier release. Thanks for the fix, I'll apply this to perf-tools for v6.19. Namhyung > --- > tools/perf/builtin-buildid-cache.c | 6 ++++-- > tools/perf/util/libbfd.c | 4 +++- > tools/perf/util/symbol-elf.c | 4 +++- > tools/perf/util/symbol-minimal.c | 4 +++- > 4 files changed, 13 insertions(+), 5 deletions(-) > > diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c > index c98104481c8a..539e779e3268 100644 > --- a/tools/perf/builtin-buildid-cache.c > +++ b/tools/perf/builtin-buildid-cache.c > @@ -276,12 +276,14 @@ static bool dso__missing_buildid_cache(struct dso *dso, int parm __maybe_unused) > { > char filename[PATH_MAX]; > struct build_id bid = { .size = 0, }; > + int err; > > if (!dso__build_id_filename(dso, filename, sizeof(filename), false)) > return true; > > - if (filename__read_build_id(filename, &bid) == -1) { > - if (errno == ENOENT) > + err = filename__read_build_id(filename, &bid); > + if (err < 0) { > + if (err == -ENOENT) > return false; > > pr_warning("Problems with %s file, consider removing it from the cache\n", > diff --git a/tools/perf/util/libbfd.c b/tools/perf/util/libbfd.c > index 0099b415decc..edf0829e9635 100644 > --- a/tools/perf/util/libbfd.c > +++ b/tools/perf/util/libbfd.c > @@ -391,8 +391,10 @@ int libbfd__read_build_id(const char *filename, struct build_id *bid) > > if (!filename) > return -EFAULT; > + > + errno = 0; > if (!is_regular_file(filename)) > - return -EWOULDBLOCK; > + return errno == 0 ? -EWOULDBLOCK : -errno; > > fd = open(filename, O_RDONLY); > if (fd < 0) > diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c > index 957143fbf8a0..d1dcafa4b3b8 100644 > --- a/tools/perf/util/symbol-elf.c > +++ b/tools/perf/util/symbol-elf.c > @@ -902,8 +902,10 @@ int filename__read_build_id(const char *filename, struct build_id *bid) > > if (!filename) > return -EFAULT; > + > + errno = 0; > if (!is_regular_file(filename)) > - return -EWOULDBLOCK; > + return errno == 0 ? -EWOULDBLOCK : -errno; > > err = kmod_path__parse(&m, filename); > if (err) > diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c > index c6b17c14a2e9..8221dc9868f7 100644 > --- a/tools/perf/util/symbol-minimal.c > +++ b/tools/perf/util/symbol-minimal.c > @@ -104,8 +104,10 @@ int filename__read_build_id(const char *filename, struct build_id *bid) > > if (!filename) > return -EFAULT; > + > + errno = 0; > if (!is_regular_file(filename)) > - return -EWOULDBLOCK; > + return errno == 0 ? -EWOULDBLOCK : -errno; > > fd = open(filename, O_RDONLY); > if (fd < 0) > -- > 2.52.0.223.gf5cc29aaa4-goog >