From: Jiri Olsa <jolsa@redhat.com>
To: Song Liu <songliubraving@fb.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
ast@kernel.org, daniel@iogearbox.net, kernel-team@fb.com,
peterz@infradead.org, acme@redhat.com, jolsa@kernel.org,
namhyung@kernel.org
Subject: Re: [PATCH v5 perf,bpf 07/15] perf, bpf: save bpf_prog_info information as headers to perf.data
Date: Mon, 4 Mar 2019 14:52:10 +0100 [thread overview]
Message-ID: <20190304135210.GB19809@krava> (raw)
In-Reply-To: <20190228050643.958685-8-songliubraving@fb.com>
On Wed, Feb 27, 2019 at 09:06:35PM -0800, Song Liu wrote:
SNIP
> +static int process_bpf_prog_info(struct feat_fd *ff,
> + void *data __maybe_unused)
> +{
> + struct bpf_prog_info_linear *info_linear;
> + struct bpf_prog_info_node *info_node;
> + struct perf_env *env = &ff->ph->env;
> + u32 count, i;
> + int err = -1;
> +
> + if (do_read_u32(ff, &count))
> + return -1;
> +
> + down_write(&env->bpf_progs.lock);
> +
> + for (i = 0; i < count; ++i) {
> + u32 info_len, data_len;
> +
> + info_linear = NULL;
> + info_node = NULL;
> + if (do_read_u32(ff, &info_len))
> + goto out;
> + if (do_read_u32(ff, &data_len))
> + goto out;
> +
> + if (info_len > sizeof(struct bpf_prog_info)) {
> + pr_warning("detected invalid bpf_prog_info\n");
> + goto out;
> + }
> +
> + info_linear = malloc(sizeof(struct bpf_prog_info_linear) +
> + data_len);
> + if (!info_linear)
> + goto out;
> + info_linear->info_len = sizeof(struct bpf_prog_info);
> + info_linear->data_len = data_len;
> + if (do_read_u64(ff, (u64 *)(&info_linear->arrays)))
> + goto out;
> + if (__do_read(ff, &info_linear->info, info_len))
> + goto out;
> + if (info_len < sizeof(struct bpf_prog_info))
> + memset(((void *)(&info_linear->info)) + info_len, 0,
> + sizeof(struct bpf_prog_info) - info_len);
> +
> + if (__do_read(ff, info_linear->data, data_len))
> + goto out;
> +
> + /* endian mismatch, drop the info, continue */
> + if (ff->ph->needs_swap) {
> + free(info_linear);
> + continue;
> + }
so in this case we can check for needs_swap in the begining
of the function and bail out without reading all the data
also please display soem error message saying we don't support
ebpf progs data report over the different endianity
jirka
next prev parent reply other threads:[~2019-03-04 13:52 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-28 5:06 [PATCH v5 perf,bpf 00/15] perf annotation of BPF programs Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 01/15] perf, bpf: consider events with attr.bpf_event as side-band events Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 02/15] bpf: libbpf: introduce bpf_program__get_prog_info_linear() Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 03/15] bpf: bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump() Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 04/15] perf, bpf: synthesize bpf events with bpf_program__get_prog_info_linear() Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 05/15] perf: change prototype of perf_event__synthesize_bpf_events() Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 06/15] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 07/15] perf, bpf: save bpf_prog_info information as headers to perf.data Song Liu
2019-03-04 13:52 ` Jiri Olsa [this message]
2019-03-04 19:36 ` Song Liu
2019-03-04 20:23 ` Jiri Olsa
2019-03-04 20:31 ` Song Liu
2019-03-04 13:52 ` Jiri Olsa
2019-03-04 13:52 ` Jiri Olsa
2019-03-04 19:41 ` Song Liu
2019-03-04 20:37 ` Jiri Olsa
2019-03-04 13:52 ` Jiri Olsa
2019-02-28 5:06 ` [PATCH v5 perf,bpf 08/15] perf, bpf: save btf in a rbtree in perf_env Song Liu
2019-03-04 13:52 ` Jiri Olsa
2019-03-04 19:43 ` Song Liu
2019-03-04 20:31 ` Jiri Olsa
2019-03-04 13:53 ` Jiri Olsa
2019-02-28 5:06 ` [PATCH v5 perf,bpf 09/15] perf, bpf: save btf information as headers to perf.data Song Liu
2019-03-04 13:52 ` Jiri Olsa
2019-02-28 5:06 ` [PATCH v5 perf,bpf 10/15] perf-top: add option --no-bpf-event Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 11/15] perf: add -lopcodes to feature-libbfd Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 12/15] perf, bpf: enable annotation of bpf program Song Liu
2019-03-04 13:52 ` Jiri Olsa
2019-03-04 13:53 ` Jiri Olsa
2019-03-04 20:52 ` Song Liu
2019-03-04 13:53 ` Jiri Olsa
2019-03-04 19:45 ` Song Liu
2019-03-04 20:37 ` Jiri Olsa
2019-03-04 20:43 ` Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 13/15] perf, bpf: process PERF_BPF_EVENT_PROG_LOAD for annotation Song Liu
2019-03-04 13:53 ` Jiri Olsa
2019-02-28 5:06 ` [PATCH v5 perf,bpf 14/15] perf: introduce side band thread Song Liu
2019-02-28 5:06 ` [PATCH v5 perf,bpf 15/15] perf, bpf: save bpf_prog_info and btf of short living bpf programs Song Liu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190304135210.GB19809@krava \
--to=jolsa@redhat.com \
--cc=acme@redhat.com \
--cc=ast@kernel.org \
--cc=daniel@iogearbox.net \
--cc=jolsa@kernel.org \
--cc=kernel-team@fb.com \
--cc=linux-kernel@vger.kernel.org \
--cc=namhyung@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=songliubraving@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox