On Thursday, 9 February 2023 20:32:31 CET Janusz Krzysztofik wrote:
> If any of *-without-i915 subtests fails or skips for any reason, it may
> leave the i915 module unloaded while keeping our device list populated
> with initially collected data. In a follow up igt_fixture section we then
> try to reopen the device. If the test has been executed with a device
> filter specified, an attempt to open the device finds a matching entry
> that belongs to the no longer existing device in that initially collected
> device list, fails to stat() it, concludes that's because of the device
> having been already open, and returns an error.
>
> Fix this potentially confusing test result by freeing the potentially
> outdated device list before continuing with drm_open_driver().
Freeing device list occurred not safe if device scan was not performed before.
I can see 3 potential solutions:
1) force device rescan instead of free before calling drm_open_driver(),
2) teach igt_device_free() to return immediately if the device list has not
been allocated,
3) provide a has_device_list() helper for to be used if not sure before
calling igt_device_free().
Any preferences?
Thanks,
Janusz
>
> While being at it, add a comment that explains why we call
> igt_device_scan() from __igt_device_card_match() but don't force device
> rescan, and emit a debug message if we fail in _is_already_opened() on
> unsuccessful device stat().
>
> Subtest basic-s3-without-i915: FAIL (9.572s)
> (i915_suspend:9050) drmtest-WARNING: card maching filter 0 is already opened
> (i915_suspend:9050) drmtest-CRITICAL: Test abort in function drm_open_driver, file ../lib/drmtest.c:639:
> (i915_suspend:9050) drmtest-CRITICAL: abort condition: fd < 0
> (i915_suspend:9050) drmtest-CRITICAL: Last errno: 2, No such file or directory
> (i915_suspend:9050) drmtest-CRITICAL: No known gpu found for chipset flags 0x1 (intel)
> Test i915_suspend failed.
> **** DEBUG ****
> (i915_suspend:9050) drmtest-DEBUG: Looking for devices to open using filter 0: pci:vendor=intel,device=dg2
> (i915_suspend:9050) drmtest-DEBUG: Filter matched /dev/dri/card0 | /dev/dri/renderD128
> (i915_suspend:9050) drmtest-WARNING: card maching filter 0 is already opened
> (i915_suspend:9050) drmtest-CRITICAL: Test abort in function drm_open_driver, file ../lib/drmtest.c:639:
> (i915_suspend:9050) drmtest-CRITICAL: abort condition: fd < 0
> (i915_suspend:9050) drmtest-CRITICAL: Last errno: 2, No such file or directory
> (i915_suspend:9050) drmtest-CRITICAL: No known gpu found for chipset flags 0x1 (intel)
> (i915_suspend:9050) igt_core-INFO: Stack trace:
> (i915_suspend:9050) igt_core-INFO: #0 ../lib/igt_core.c:2066 __igt_abort()
> (i915_suspend:9050) igt_core-INFO: #1 ../lib/drmtest.c:573 drm_open_driver()
> (i915_suspend:9050) igt_core-INFO: #2 ../tests/i915/i915_suspend.c:258 __igt_unique____real_main245()
> (i915_suspend:9050) igt_core-INFO: #3 ../tests/i915/i915_suspend.c:245 main()
> (i915_suspend:9050) igt_core-INFO: #4 ../sysdeps/nptl/libc_start_call_main.h:58 __libc_start_call_main()
> (i915_suspend:9050) igt_core-INFO: #5 ../csu/libc-start.c:128 __libc_start_main@@GLIBC_2.34()
> (i915_suspend:9050) igt_core-INFO: #6 [_start+0x2a]
> **** END ****
>
> Fixes: f7aff600ab16 ("tests/i915/i915_suspend: Disable d3cold_allowed for basic-s2idle-without-i915")
> Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@xxxxxxxxxxxxxxx>
> Cc: Riana Tauro <riana.tauro@xxxxxxxxx>
> ---
> lib/drmtest.c | 2 +-
> lib/igt_device_scan.c | 4 ++++
> tests/i915/i915_suspend.c | 10 +++++++++-
> 3 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/lib/drmtest.c b/lib/drmtest.c
> index 16e80bdfcf..8e2d1ac50b 100644
> --- a/lib/drmtest.c
> +++ b/lib/drmtest.c
> @@ -260,7 +260,7 @@ static bool _is_already_opened(const char *path, int as_idx)
> * we cannot even stat the device, so it's of no use - let's claim it's
> * already opened
> */
> - if (stat(path, &new) != 0)
> + if (igt_debug_on(stat(path, &new) != 0))
> return true;
>
> for (int i = 0; i < as_idx; ++i) {
> diff --git a/lib/igt_device_scan.c b/lib/igt_device_scan.c
> index 8b767eed20..ae69ed09f1 100644
> --- a/lib/igt_device_scan.c
> +++ b/lib/igt_device_scan.c
> @@ -1918,6 +1918,10 @@ static bool __igt_device_card_match(const char *filter,
> return false;
> memset(card, 0, sizeof(*card));
>
> + /*
> + * Scan devices in case the user hasn't yet,
> + * but leave a decision on forced rescan on the user side.
> + */
> igt_devices_scan(false);
>
> if (igt_device_filter_apply(filter) == false)
> diff --git a/tests/i915/i915_suspend.c b/tests/i915/i915_suspend.c
> index 815f1c8a2c..c68110476e 100644
> --- a/tests/i915/i915_suspend.c
> +++ b/tests/i915/i915_suspend.c
> @@ -253,8 +253,16 @@ igt_main
> igt_subtest("basic-s3-without-i915")
> test_suspend_without_i915(SUSPEND_STATE_S3);
>
> - igt_fixture
> + igt_fixture {
> + /*
> + * Since above tests may fail leaving the i915 module unloaded,
> + * force refresh of device list before opening an i915 device
> + * by cleaning up the current device list, otherwise we can fail
> + * if we have been called with a device filter specified.
> + */
> + igt_devices_free();
> fd = drm_open_driver(DRIVER_INTEL);
> + }
>
> igt_subtest("fence-restore-tiled2untiled") {
> gem_require_mappable_ggtt(fd);
>
