selftests/landlock: UX improvements #7
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A typical sequence for someone running this test for the first time might be: make kselftest TARGETS="landlock" (sees a bunch of "Permission denied", realizes that sudo is needed) sudo make kselftest TARGETS="landlock" (sees a bunch of "File exists", scratches head) This ensures that the newly created directory is cleaned up by the first attempt (and also gives a slightly more helpful message explaining the cause). See proposal in patch 3 message for a more generic solution - this might not be necessary. Signed-off-by: Tingmao Wang <m@maowtm.org>
Because we drop capabilities (most importantly, CAP_DAC_OVERRIDE), if a user runs the selftests under a Linux source checked out by a non-root user, the test will fail even when ran under sudo, and will print a "Permission denied" error. This creates a confusing situation if they does not realize that the test drops capabilities, and can mislead users to think there's something wrong with the test or landlock. This patch produces output that looks like: # # RUN layout0.ruleset_with_unknown_access ... # # fs_test.c:240:ruleset_with_unknown_access:Expected 0 (0) == mkdir(path, 0700) (-1) # # fs_test.c:244:ruleset_with_unknown_access:Failed to create directory "tmp": Permission denied # # fs_test.c:230:ruleset_with_unknown_access:Hint: fs_tests requires permissions for uid 0 on test directory /home/mao/landlock-selftests/tools/testing/selftests/landlock and files under it (even when running as root). # # fs_test.c:232:ruleset_with_unknown_access: Try chmod a+rwX -R /home/mao/landlock-selftests/tools/testing/selftests/landlock # # ruleset_with_unknown_access: Test terminated by assertion # # FAIL layout0.ruleset_with_unknown_access Signed-off-by: Tingmao Wang <m@maowtm.org>
This ensures that if for whatever reason FIXTURE_SETUP fails, the next test run will handle this gracefully. I don't actually 100% like this approach - maybe we should consider enhancing the test framework to add a FIXTURE_TEARDOWN_ALWAYS, that will run even if FIXTURE_SETUP fails? Signed-off-by: Tingmao Wang <m@maowtm.org>
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When s_start() fails to allocate memory for set_event_iter, it returns NULL before acquiring event_mutex. However, the corresponding s_stop() function always tries to unlock the mutex, causing a lock imbalance warning: WARNING: bad unlock balance detected! 6.17.0-rc7-00175-g2b2e0c04f78c #7 Not tainted ------------------------------------- syz.0.85611/376514 is trying to release lock (event_mutex) at: [<ffffffff8dafc7a4>] traverse.part.0.constprop.0+0x2c4/0x650 fs/seq_file.c:131 but there are no more locks to release! The issue was introduced by commit b355247 ("tracing: Cache ':mod:' events for modules not loaded yet") which added the kzalloc() allocation before the mutex lock, creating a path where s_start() could return without locking the mutex while s_stop() would still try to unlock it. Fix this by unconditionally acquiring the mutex immediately after allocation, regardless of whether the allocation succeeded. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/20250929113238.3722055-1-sashal@kernel.org Fixes: b355247 ("tracing: Cache ":mod:" events for modules not loaded yet") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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When interrupting perf stat in repeat mode with a signal the signal is passed to the child process but the repeat doesn't terminate: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] ^Csleep: Interrupt [ perf stat: executing run #3 ... ] [ perf stat: executing run #4 ... ] [ perf stat: executing run #5 ... ] [ perf stat: executing run #6 ... ] [ perf stat: executing run #7 ... ] [ perf stat: executing run #8 ... ] [ perf stat: executing run #9 ... ] [ perf stat: executing run #10 ... ] Performance counter stats for 'sleep 1' (10 runs): 0.9500 +- 0.0512 seconds time elapsed ( +- 5.39% ) 0.01user 0.02system 0:09.53elapsed 0%CPU (0avgtext+0avgdata 18940maxresident)k 29944inputs+0outputs (0major+2629minor)pagefaults 0swaps ``` Terminate the repeated run and give a reasonable exit value: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] [ perf stat: executing run #3 ... ] ^Csleep: Interrupt Performance counter stats for 'sleep 1' (10 runs): 0.680 +- 0.321 seconds time elapsed ( +- 47.16% ) Command exited with non-zero status 130 0.00user 0.01system 0:02.05elapsed 0%CPU (0avgtext+0avgdata 70688maxresident)k 0inputs+0outputs (0major+5002minor)pagefaults 0swaps ``` Note, this also changes the exit value for non-repeat runs when interrupted by a signal. Reported-by: Ingo Molnar <mingo@kernel.org> Closes: https://lore.kernel.org/lkml/aS5wjmbAM9ka3M2g@gmail.com/ Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Since commit a735831 ("drm/nouveau: vendor in drm_encoder_slave API") nouveau appears to be broken for all dispnv04 GPUs (before NV50). Depending on the kernel version, either having no display output and hanging in kernel for a long time, or even oopsing in the cleanup path like: Hardware name: PowerMac11,2 PPC970MP 0x440101 PowerMac ... nouveau 0000:0a:00.0: drm: 0x14C5: Parsing digital output script table BUG: Unable to handle kernel data access on read at 0x00041520 Faulting instruction address: 0xc0003d0001be0844 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=8 NUMA PowerMac Modules linked in: windfarm_cpufreq_clamp windfarm_smu_sensors windfarm_smu_controls windfarm_pm112 snd_aoa_codec_onyx snd_aoa_fabric_layout snd_aoa windfarm_pid jo apple_mfi_fastcharge rndis_host cdc_ether usbnet mii snd_aoa_i2sbus snd_aoa_soundbus snd_pcm snd_timer snd soundcore rack_meter windfarm_smu_sat windfarm_max6690_s m75_sensor windfarm_core gpu_sched drm_gpuvm drm_exec drm_client_lib drm_ttm_helper ttm drm_display_helper drm_kms_helper drm drm_panel_orientation_quirks syscopyar _sys_fops i2c_algo_bit backlight uio_pdrv_genirq uio uninorth_agp agpgart zram dm_mod dax ipv6 nfsv4 dns_resolver nfs lockd grace sunrpc offb cfbfillrect cfbimgblt ont input_leds sr_mod cdrom sd_mod uas ata_generic hid_apple hid_generic usbhid hid usb_storage pata_macio sata_svw libata firewire_ohci scsi_mod firewire_core ohci ehci_pci ehci_hcd tg3 ohci_hcd libphy usbcore usb_common nls_base led_class CPU: 0 UID: 0 PID: 245 Comm: (udev-worker) Not tainted 6.14.0-09584-g7d06015d936c #7 PREEMPTLAZY Hardware name: PowerMac11,2 PPC970MP 0x440101 PowerMac NIP: c0003d0001be0844 LR: c0003d0001be0830 CTR: 0000000000000000 REGS: c0000000053f70e0 TRAP: 0300 Not tainted (6.14.0-09584-g7d06015d936c) MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI> CR: 24222220 XER: 00000000 DAR: 0000000000041520 DSISR: 40000000 IRQMASK: 0 \x0aGPR00: c0003d0001be0830 c0000000053f7380 c0003d0000911900 c000000007bc6800 \x0aGPR04: 0000000000000000 0000000000000000 c000000007bc6e70 0000000000000001 \x0aGPR08: 01f3040000000000 0000000000041520 0000000000000000 c0003d0000813958 \x0aGPR12: c000000000071a48 c000000000e28000 0000000000000020 0000000000000000 \x0aGPR16: 0000000000000000 0000000000f52630 0000000000000000 0000000000000000 \x0aGPR20: 0000000000000000 0000000000000000 0000000000000001 c0003d0000928528 \x0aGPR24: c0003d0000928598 0000000000000000 c000000007025480 c000000007025480 \x0aGPR28: c0000000010b4000 0000000000000000 c000000007bc1800 c000000007bc6800 NIP [c0003d0001be0844] nv_crtc_destroy+0x44/0xd4 [nouveau] LR [c0003d0001be0830] nv_crtc_destroy+0x30/0xd4 [nouveau] Call Trace: [c0000000053f7380] [c0003d0001be0830] nv_crtc_destroy+0x30/0xd4 [nouveau] (unreliable) [c0000000053f73c0] [c0003d00007f7bf4] drm_mode_config_cleanup+0x27c/0x30c [drm] [c0000000053f7490] [c0003d0001bdea50] nouveau_display_create+0x1cc/0x550 [nouveau] [c0000000053f7500] [c0003d0001bcc29c] nouveau_drm_device_init+0x1c8/0x844 [nouveau] [c0000000053f75e0] [c0003d0001bcc9ec] nouveau_drm_probe+0xd4/0x1e0 [nouveau] [c0000000053f7670] [c000000000557d24] local_pci_probe+0x50/0xa8 [c0000000053f76f0] [c000000000557fa8] pci_device_probe+0x22c/0x240 [c0000000053f7760] [c0000000005fff3c] really_probe+0x188/0x31c [c0000000053f77e0] [c000000000600204] __driver_probe_device+0x134/0x13c [c0000000053f7860] [c0000000006002c0] driver_probe_device+0x3c/0xb4 [c0000000053f78a0] [c000000000600534] __driver_attach+0x118/0x128 [c0000000053f78e0] [c0000000005fe038] bus_for_each_dev+0xa8/0xf4 [c0000000053f7950] [c0000000005ff460] driver_attach+0x2c/0x40 [c0000000053f7970] [c0000000005fea68] bus_add_driver+0x130/0x278 [c0000000053f7a00] [c00000000060117c] driver_register+0x9c/0x1a0 [c0000000053f7a80] [c00000000055623c] __pci_register_driver+0x5c/0x70 [c0000000053f7aa0] [c0003d0001c058a0] nouveau_drm_init+0x254/0x278 [nouveau] [c0000000053f7b10] [c00000000000e9bc] do_one_initcall+0x84/0x268 [c0000000053f7bf0] [c0000000001a0ba0] do_init_module+0x70/0x2d8 [c0000000053f7c70] [c0000000001a42bc] init_module_from_file+0xb4/0x108 [c0000000053f7d50] [c0000000001a4504] sys_finit_module+0x1ac/0x478 [c0000000053f7e10] [c000000000023230] system_call_exception+0x1a4/0x20c [c0000000053f7e50] [c00000000000c554] system_call_common+0xf4/0x258 --- interrupt: c00 at 0xfd5f988 NIP: 000000000fd5f988 LR: 000000000ff9b148 CTR: 0000000000000000 REGS: c0000000053f7e80 TRAP: 0c00 Not tainted (6.14.0-09584-g7d06015d936c) MSR: 100000000000d032 <HV,EE,PR,ME,IR,DR,RI> CR: 28222244 XER: 00000000 IRQMASK: 0 \x0aGPR00: 0000000000000161 00000000ffcdc2d0 00000000405db160 0000000000000020 \x0aGPR04: 000000000ffa2c9c 0000000000000000 000000000000001f 0000000000000045 \x0aGPR08: 0000000011a13770 0000000000000000 0000000000000000 0000000000000000 \x0aGPR12: 0000000000000000 0000000010249d8c 0000000000000020 0000000000000000 \x0aGPR16: 0000000000000000 0000000000f52630 0000000000000000 0000000000000000 \x0aGPR20: 0000000000000000 0000000000000000 0000000000000000 0000000011a11a70 \x0aGPR24: 0000000011a13580 0000000011a11950 0000000011a11a70 0000000000020000 \x0aGPR28: 000000000ffa2c9c 0000000000000000 000000000ffafc40 0000000011a11a70 NIP [000000000fd5f988] 0xfd5f988 LR [000000000ff9b148] 0xff9b148 --- interrupt: c00 Code: f821ffc1 418200ac e93f0000 e9290038 e9291468 eba90000 48026c0d e8410018 e93f06aa 3d290001 392982a4 79291f24 <7fdd482a> 2c3e0000 41820030 7fc3f378 ---[ end trace 0000000000000000 ]--- This is caused by the i2c encoder modules vendored into nouveau/ now depending on the equally vendored nouveau_i2c_encoder_destroy function. Trying to auto-load this modules hangs on nouveau initialization until timeout, and nouveau continues without i2c video encoders. Fix by avoiding nouveau dependency by __always_inlining that helper functions into those i2c video encoder modules. Fixes: a735831 ("drm/nouveau: vendor in drm_encoder_slave API") Signed-off-by: René Rebe <rene@exactco.de> Reviewed-by: Lyude Paul <lyude@redhat.com> [Lyude: fixed commit reference in description] Signed-off-by: Lyude Paul <lyude@redhat.com> Link: https://patch.msgid.link/20251202.164952.2216481867721531616.rene@exactco.de
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