[bpf-next,v3,1/2] bpftool: mark orphaned programs during prog show

Commit Message

Stanislav Fomichev Nov. 27, 2023, 6:20 p.m. UTC

Commit ef01f4e25c17 ("bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD
and PERF_BPF_EVENT_PROG_UNLOAD") stopped removing program's id from
idr when the offloaded/bound netdev goes away. I was supposed to
take a look and check in [0], but apparently I did not.

Martin points out it might be useful to keep it that way for
observability sake, but we at least need to mark those programs as
unusable.

Mark those programs as 'orphaned' and keep printing the list when
we encounter ENODEV.

0: unspec  tag 0000000000000000
        xlated 0B  not jited  memlock 4096B  orphaned

[0]: https://lore.kernel.org/all/[e-mail]/

v3:
* use two spaces for "  orphaned" (Quentin)

Cc: [e-mail]
Fixes: ef01f4e25c17 ("bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD and PERF_BPF_EVENT_PROG_UNLOAD")
Signed-off-by: Stanislav Fomichev <[e-mail]>
---
 tools/bpf/bpftool/prog.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

Comments

Quentin Monnet Nov. 27, 2023, 10:42 p.m. UTC | #1

On Mon, 27 Nov 2023 at 18:21, Stanislav Fomichev <[e-mail]> wrote:
>
> Commit ef01f4e25c17 ("bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD
> and PERF_BPF_EVENT_PROG_UNLOAD") stopped removing program's id from
> idr when the offloaded/bound netdev goes away. I was supposed to
> take a look and check in [0], but apparently I did not.
>
> Martin points out it might be useful to keep it that way for
> observability sake, but we at least need to mark those programs as
> unusable.
>
> Mark those programs as 'orphaned' and keep printing the list when
> we encounter ENODEV.
>
> 0: unspec  tag 0000000000000000
>         xlated 0B  not jited  memlock 4096B  orphaned
>
> [0]: https://lore.kernel.org/all/[e-mail]/
>
> v3:
> * use two spaces for "  orphaned" (Quentin)
>
> Cc: [e-mail]
> Fixes: ef01f4e25c17 ("bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD and PERF_BPF_EVENT_PROG_UNLOAD")
> Signed-off-by: Stanislav Fomichev <[e-mail]>

Reviewed-by: Quentin Monnet <[e-mail]>

Thanks!

[e-mail] Nov. 28, 2023, 2:30 a.m. UTC | #2

Hello:

This series was applied to bpf/bpf-next.git (master)
by Martin KaFai Lau <[e-mail]>:

On Mon, 27 Nov 2023 10:20:56 -0800 you wrote:
> Commit ef01f4e25c17 ("bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD
> and PERF_BPF_EVENT_PROG_UNLOAD") stopped removing program's id from
> idr when the offloaded/bound netdev goes away. I was supposed to
> take a look and check in [0], but apparently I did not.
> 
> Martin points out it might be useful to keep it that way for
> observability sake, but we at least need to mark those programs as
> unusable.
> 
> [...]

Here is the summary with links:
  - [bpf-next,v3,1/2] bpftool: mark orphaned programs during prog show
    https://git.kernel.org/bpf/bpf-next/c/876843ce1e48
  - [bpf-next,v3,2/2] selftests/bpf: update test_offload to use new orphaned property
    https://git.kernel.org/bpf/bpf-next/c/cf9791631027

You are awesome, thank you!

Patch

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 7ec4f5671e7a..feb8e305804f 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -442,7 +442,7 @@  static void print_prog_header_json(struct bpf_prog_info *info, int fd)
 		jsonw_uint_field(json_wtr, "recursion_misses", info->recursion_misses);
 }
 
-static void print_prog_json(struct bpf_prog_info *info, int fd)
+static void print_prog_json(struct bpf_prog_info *info, int fd, bool orphaned)
 {
 	char *memlock;
 
@@ -461,6 +461,7 @@  static void print_prog_json(struct bpf_prog_info *info, int fd)
 		jsonw_uint_field(json_wtr, "uid", info->created_by_uid);
 	}
 
+	jsonw_bool_field(json_wtr, "orphaned", orphaned);
 	jsonw_uint_field(json_wtr, "bytes_xlated", info->xlated_prog_len);
 
 	if (info->jited_prog_len) {
@@ -527,7 +528,7 @@  static void print_prog_header_plain(struct bpf_prog_info *info, int fd)
 	printf("\n");
 }
 
-static void print_prog_plain(struct bpf_prog_info *info, int fd)
+static void print_prog_plain(struct bpf_prog_info *info, int fd, bool orphaned)
 {
 	char *memlock;
 
@@ -554,6 +555,9 @@  static void print_prog_plain(struct bpf_prog_info *info, int fd)
 		printf("  memlock %sB", memlock);
 	free(memlock);
 
+	if (orphaned)
+		printf("  orphaned");
+
 	if (info->nr_map_ids)
 		show_prog_maps(fd, info->nr_map_ids);
 
@@ -581,15 +585,15 @@  static int show_prog(int fd)
 	int err;
 
 	err = bpf_prog_get_info_by_fd(fd, &info, &len);
-	if (err) {
+	if (err && err != -ENODEV) {
 		p_err("can't get prog info: %s", strerror(errno));
 		return -1;
 	}
 
 	if (json_output)
-		print_prog_json(&info, fd);
+		print_prog_json(&info, fd, err == -ENODEV);
 	else
-		print_prog_plain(&info, fd);
+		print_prog_plain(&info, fd, err == -ENODEV);
 
 	return 0;
 }