Re: [PATCH bpf-next] bpf/selftests: remove lirc test

[Sean Young <sean@mess.org>]

On Fri, Jun 05, 2026 at 06:39:51AM -0700, Alexei Starovoitov wrote:
> On Fri, Jun 5, 2026 at 12:58 AM Bastien Curutchet (eBPF Foundation)
> <bastien.curutchet@bootlin.com> wrote:
> >
> > test_lirc_mode.sh fails with the following when run from the vmtest VM:
> > root@(none):/root/bpf# ./test_lirc_mode2.sh
> > Failed to read decoded IR: Resource temporarily unavailable
> > FAIL: lirc_mode2
> >
> > As part of the ongoing effort to get rid of any standalone test, this
> > script should either be fixed and converted to test_progs or removed.
> >
> > Remove it.
> 
> cc Sean

I've sent a fix to for the test in a separate email.

This regressed a long time ago; is anyone running these tests? There is
not much point to selftests if they're not run by anyone. I should add
them to linux-media CI, but is anyone in bpf running them?

I am not familiar with test_progs, what's that?

Sean

> > Signed-off-by: Bastien Curutchet (eBPF Foundation) <bastien.curutchet@bootlin.com>
> > ---
> > Hi all,
> >
> > I went back up to v6.13 without finding a working commit. Maybe
> > something's wrong with my setup but comments inside
> > test_lirc_mode2_user.c say that three kernel configurations are needed
> > to have the test working and I ensured they were indeed enabled (with
> > s/BPF_RAWIR_EVENT/BPF_LIRC_MODE2).
> >
> > If someone disagrees with this removal please speak up and I'll
> > investigate this further.
> >
> > Best regards,
> > Bastien
> > ---
> >  tools/testing/selftests/bpf/.gitignore             |   1 -
> >  tools/testing/selftests/bpf/Makefile               |   3 -
> >  .../selftests/bpf/progs/test_lirc_mode2_kern.c     |  26 ---
> >  tools/testing/selftests/bpf/test_lirc_mode2.sh     |  41 -----
> >  tools/testing/selftests/bpf/test_lirc_mode2_user.c | 177 ---------------------
> >  5 files changed, 248 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
> > index 986a6389186ba..b815bf0d88774 100644
> > --- a/tools/testing/selftests/bpf/.gitignore
> > +++ b/tools/testing/selftests/bpf/.gitignore
> > @@ -17,7 +17,6 @@ test_verifier_log
> >  feature
> >  urandom_read
> >  test_sockmap
> > -test_lirc_mode2_user
> >  flow_dissector_load
> >  test_tcpnotify_user
> >  test_libbpf
> > diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> > index bc049620c7745..653c949fc854d 100644
> > --- a/tools/testing/selftests/bpf/Makefile
> > +++ b/tools/testing/selftests/bpf/Makefile
> > @@ -117,7 +117,6 @@ TEST_FILES = xsk_prereqs.sh $(wildcard progs/btf_dump_test_case_*.c)
> >
> >  # Order correspond to 'make run_tests' order
> >  TEST_PROGS := test_kmod.sh \
> > -       test_lirc_mode2.sh \
> >         test_bpftool_build.sh \
> >         test_doc_build.sh \
> >         test_xsk.sh \
> > @@ -135,7 +134,6 @@ TEST_GEN_PROGS_EXTENDED = \
> >         bench \
> >         flow_dissector_load \
> >         test_cpp \
> > -       test_lirc_mode2_user \
> >         veristat \
> >         xdp_features \
> >         xdp_hw_metadata \
> > @@ -325,7 +323,6 @@ $(OUTPUT)/test_sockmap: $(CGROUP_HELPERS) $(TESTING_HELPERS)
> >  $(OUTPUT)/test_tcpnotify_user: $(CGROUP_HELPERS) $(TESTING_HELPERS) $(TRACE_HELPERS)
> >  $(OUTPUT)/test_sock_fields: $(CGROUP_HELPERS) $(TESTING_HELPERS)
> >  $(OUTPUT)/test_tag: $(TESTING_HELPERS)
> > -$(OUTPUT)/test_lirc_mode2_user: $(TESTING_HELPERS)
> >  $(OUTPUT)/flow_dissector_load: $(TESTING_HELPERS)
> >  $(OUTPUT)/test_maps: $(TESTING_HELPERS)
> >  $(OUTPUT)/test_verifier: $(TESTING_HELPERS) $(CAP_HELPERS) $(UNPRIV_HELPERS)
> > diff --git a/tools/testing/selftests/bpf/progs/test_lirc_mode2_kern.c b/tools/testing/selftests/bpf/progs/test_lirc_mode2_kern.c
> > deleted file mode 100644
> > index 7a6620671a833..0000000000000
> > --- a/tools/testing/selftests/bpf/progs/test_lirc_mode2_kern.c
> > +++ /dev/null
> > @@ -1,26 +0,0 @@
> > -// SPDX-License-Identifier: GPL-2.0
> > -// test ir decoder
> > -//
> > -// Copyright (C) 2018 Sean Young <sean@mess.org>
> > -
> > -#include <linux/bpf.h>
> > -#include <linux/lirc.h>
> > -#include <bpf/bpf_helpers.h>
> > -
> > -SEC("lirc_mode2")
> > -int bpf_decoder(unsigned int *sample)
> > -{
> > -       if (LIRC_IS_PULSE(*sample)) {
> > -               unsigned int duration = LIRC_VALUE(*sample);
> > -
> > -               if (duration & 0x10000)
> > -                       bpf_rc_keydown(sample, 0x40, duration & 0xffff, 0);
> > -               if (duration & 0x20000)
> > -                       bpf_rc_pointer_rel(sample, (duration >> 8) & 0xff,
> > -                                          duration & 0xff);
> > -       }
> > -
> > -       return 0;
> > -}
> > -
> > -char _license[] SEC("license") = "GPL";
> > diff --git a/tools/testing/selftests/bpf/test_lirc_mode2.sh b/tools/testing/selftests/bpf/test_lirc_mode2.sh
> > deleted file mode 100755
> > index 5252b91f48a18..0000000000000
> > --- a/tools/testing/selftests/bpf/test_lirc_mode2.sh
> > +++ /dev/null
> > @@ -1,41 +0,0 @@
> > -#!/bin/bash
> > -# SPDX-License-Identifier: GPL-2.0
> > -
> > -# Kselftest framework requirement - SKIP code is 4.
> > -ksft_skip=4
> > -ret=$ksft_skip
> > -
> > -msg="skip all tests:"
> > -if [ $UID != 0 ]; then
> > -       echo $msg please run this as root >&2
> > -       exit $ksft_skip
> > -fi
> > -
> > -GREEN='\033[0;92m'
> > -RED='\033[0;31m'
> > -NC='\033[0m' # No Color
> > -
> > -modprobe rc-loopback
> > -
> > -for i in /sys/class/rc/rc*
> > -do
> > -       if grep -q DRV_NAME=rc-loopback $i/uevent
> > -       then
> > -               LIRCDEV=$(grep DEVNAME= $i/lirc*/uevent | sed sQDEVNAME=Q/dev/Q)
> > -               INPUTDEV=$(grep DEVNAME= $i/input*/event*/uevent | sed sQDEVNAME=Q/dev/Q)
> > -       fi
> > -done
> > -
> > -if [ -n "$LIRCDEV" ];
> > -then
> > -       TYPE=lirc_mode2
> > -       ./test_lirc_mode2_user $LIRCDEV $INPUTDEV
> > -       ret=$?
> > -       if [ $ret -ne 0 ]; then
> > -               echo -e ${RED}"FAIL: $TYPE"${NC}
> > -       else
> > -               echo -e ${GREEN}"PASS: $TYPE"${NC}
> > -       fi
> > -fi
> > -
> > -exit $ret
> > diff --git a/tools/testing/selftests/bpf/test_lirc_mode2_user.c b/tools/testing/selftests/bpf/test_lirc_mode2_user.c
> > deleted file mode 100644
> > index 88e4aeab21b7b..0000000000000
> > --- a/tools/testing/selftests/bpf/test_lirc_mode2_user.c
> > +++ /dev/null
> > @@ -1,177 +0,0 @@
> > -// SPDX-License-Identifier: GPL-2.0
> > -// test ir decoder
> > -//
> > -// Copyright (C) 2018 Sean Young <sean@mess.org>
> > -
> > -// A lirc chardev is a device representing a consumer IR (cir) device which
> > -// can receive infrared signals from remote control and/or transmit IR.
> > -//
> > -// IR is sent as a series of pulses and space somewhat like morse code. The
> > -// BPF program can decode this into scancodes so that rc-core can translate
> > -// this into input key codes using the rc keymap.
> > -//
> > -// This test works by sending IR over rc-loopback, so the IR is processed by
> > -// BPF and then decoded into scancodes. The lirc chardev must be the one
> > -// associated with rc-loopback, see the output of ir-keytable(1).
> > -//
> > -// The following CONFIG options must be enabled for the test to succeed:
> > -// CONFIG_RC_CORE=y
> > -// CONFIG_BPF_RAWIR_EVENT=y
> > -// CONFIG_RC_LOOPBACK=y
> > -
> > -// Steps:
> > -// 1. Open the /dev/lircN device for rc-loopback (given on command line)
> > -// 2. Attach bpf_lirc_mode2 program which decodes some IR.
> > -// 3. Send some IR to the same IR device; since it is loopback, this will
> > -//    end up in the bpf program
> > -// 4. bpf program should decode IR and report keycode
> > -// 5. We can read keycode from same /dev/lirc device
> > -
> > -#include <linux/bpf.h>
> > -#include <linux/input.h>
> > -#include <errno.h>
> > -#include <stdio.h>
> > -#include <stdlib.h>
> > -#include <string.h>
> > -#include <unistd.h>
> > -#include <poll.h>
> > -#include <sys/types.h>
> > -#include <sys/ioctl.h>
> > -#include <sys/stat.h>
> > -#include <fcntl.h>
> > -
> > -#include "bpf_util.h"
> > -#include <bpf/bpf.h>
> > -#include <bpf/libbpf.h>
> > -
> > -#include "testing_helpers.h"
> > -
> > -int main(int argc, char **argv)
> > -{
> > -       struct bpf_object *obj;
> > -       int ret, lircfd, progfd, inputfd;
> > -       int testir1 = 0x1dead;
> > -       int testir2 = 0x20101;
> > -       u32 prog_ids[10], prog_flags[10], prog_cnt;
> > -
> > -       if (argc != 3) {
> > -               printf("Usage: %s /dev/lircN /dev/input/eventM\n", argv[0]);
> > -               return 2;
> > -       }
> > -
> > -       ret = bpf_prog_test_load("test_lirc_mode2_kern.bpf.o",
> > -                                BPF_PROG_TYPE_LIRC_MODE2, &obj, &progfd);
> > -       if (ret) {
> > -               printf("Failed to load bpf program\n");
> > -               return 1;
> > -       }
> > -
> > -       lircfd = open(argv[1], O_RDWR | O_NONBLOCK);
> > -       if (lircfd == -1) {
> > -               printf("failed to open lirc device %s: %m\n", argv[1]);
> > -               return 1;
> > -       }
> > -
> > -       /* Let's try detach it before it was ever attached */
> > -       ret = bpf_prog_detach2(progfd, lircfd, BPF_LIRC_MODE2);
> > -       if (ret != -ENOENT) {
> > -               printf("bpf_prog_detach2 not attached should fail: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       inputfd = open(argv[2], O_RDONLY | O_NONBLOCK);
> > -       if (inputfd == -1) {
> > -               printf("failed to open input device %s: %m\n", argv[1]);
> > -               return 1;
> > -       }
> > -
> > -       prog_cnt = 10;
> > -       ret = bpf_prog_query(lircfd, BPF_LIRC_MODE2, 0, prog_flags, prog_ids,
> > -                            &prog_cnt);
> > -       if (ret) {
> > -               printf("Failed to query bpf programs on lirc device: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       if (prog_cnt != 0) {
> > -               printf("Expected nothing to be attached\n");
> > -               return 1;
> > -       }
> > -
> > -       ret = bpf_prog_attach(progfd, lircfd, BPF_LIRC_MODE2, 0);
> > -       if (ret) {
> > -               printf("Failed to attach bpf to lirc device: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       /* Write raw IR */
> > -       ret = write(lircfd, &testir1, sizeof(testir1));
> > -       if (ret != sizeof(testir1)) {
> > -               printf("Failed to send test IR message: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       struct pollfd pfd = { .fd = inputfd, .events = POLLIN };
> > -       struct input_event event;
> > -
> > -       for (;;) {
> > -               poll(&pfd, 1, 100);
> > -
> > -               /* Read decoded IR */
> > -               ret = read(inputfd, &event, sizeof(event));
> > -               if (ret != sizeof(event)) {
> > -                       printf("Failed to read decoded IR: %m\n");
> > -                       return 1;
> > -               }
> > -
> > -               if (event.type == EV_MSC && event.code == MSC_SCAN &&
> > -                   event.value == 0xdead) {
> > -                       break;
> > -               }
> > -       }
> > -
> > -       /* Write raw IR */
> > -       ret = write(lircfd, &testir2, sizeof(testir2));
> > -       if (ret != sizeof(testir2)) {
> > -               printf("Failed to send test IR message: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       for (;;) {
> > -               poll(&pfd, 1, 100);
> > -
> > -               /* Read decoded IR */
> > -               ret = read(inputfd, &event, sizeof(event));
> > -               if (ret != sizeof(event)) {
> > -                       printf("Failed to read decoded IR: %m\n");
> > -                       return 1;
> > -               }
> > -
> > -               if (event.type == EV_REL && event.code == REL_Y &&
> > -                   event.value == 1 ) {
> > -                       break;
> > -               }
> > -       }
> > -
> > -       prog_cnt = 10;
> > -       ret = bpf_prog_query(lircfd, BPF_LIRC_MODE2, 0, prog_flags, prog_ids,
> > -                            &prog_cnt);
> > -       if (ret) {
> > -               printf("Failed to query bpf programs on lirc device: %m\n");
> > -               return 1;
> > -       }
> > -
> > -       if (prog_cnt != 1) {
> > -               printf("Expected one program to be attached\n");
> > -               return 1;
> > -       }
> > -
> > -       /* Let's try detaching it now it is actually attached */
> > -       ret = bpf_prog_detach2(progfd, lircfd, BPF_LIRC_MODE2);
> > -       if (ret) {
> > -               printf("bpf_prog_detach2: returned %m\n");
> > -               return 1;
> > -       }
> > -
> > -       return 0;
> > -}
> >
> > ---
> > base-commit: 73f574b0cd0ef87a25afdffe1d907b55f7fcc940
> > change-id: 20260604-remove-lirc-test-fc8afa634f3a
> >
> > Best regards,
> > --
> > Bastien Curutchet (eBPF Foundation) <bastien.curutchet@bootlin.com>
> >