[i-g-t] tests/intel/i915_suspend: Fix WARNs of invalid fd

[Gupta, Anshuman]

> -----Original Message-----
> From: Modem, Bhanuprakash <bhanuprakash.modem at intel.com>
> Sent: Wednesday, January 17, 2024 8:52 PM
> To: Kamil Konieczny <kamil.konieczny at linux.intel.com>; igt-
> dev at lists.freedesktop.org; Gupta, Anshuman <anshuman.gupta at intel.com>
> Subject: Re: [i-g-t] tests/intel/i915_suspend: Fix WARNs of invalid fd
> 
> Hi Kamil,
> 
> On 17-01-2024 04:42 pm, Kamil Konieczny wrote:
> > Hi Bhanuprakash,
> > On 2024-01-09 at 18:48:02 +0530, Bhanuprakash Modem wrote:
> >> Call drm_close_driver() only if fd >=0, otherwise it'll will throw WARN:
> >>
> >> (i915_suspend:7563) drmtest-WARNING: Don't attempt to close
> >> standard/invalid file descriptor: -1
> >>
> >> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> >> ---
> >>   tests/intel/i915_suspend.c | 4 +++-
> >>   1 file changed, 3 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/tests/intel/i915_suspend.c b/tests/intel/i915_suspend.c
> >> index c25805584..82cabfa41 100644
> >> --- a/tests/intel/i915_suspend.c
> >> +++ b/tests/intel/i915_suspend.c
> >> @@ -300,7 +300,9 @@ test_suspend_without_i915(int state)
> >>   		igt_pm_get_d3cold_allowed(card.pci_slot_name,
> &d3cold_allowed);
> >>   		igt_pm_set_d3cold_allowed(card.pci_slot_name, 0);
> >>   	}
> >> -	drm_close_driver(fd);
> >
> > imho proper fix would be remove this and
> > fd=__drm_open_driver(DRIVER_INTEL)
> > from this function, as function is named:
> > test_suspend_without_i915
> 
> I don't have much expertise in D states. After reading the comments in the
> subtest "When module is unloaded and s2idle is triggered, PCI core leaves the
> endpoint in D0 and the bridge in D3 state causing PCIE spec violation and
> config space is read as 0xFF. Keep the bridge in D0 before module unload to
> prevent this issue"
This is not a real time use case, either a system boots with i915 driver or not.
Removing i915 module and trigger suspend is not a valid use case but we want to test that
suspend coverage without i915. So we need to disallow d3cold(which will bring the pcie bridge to D0).
igt_pm_set_d3cold_allowed(card.pci_slot_name, 0);
***above is applicable tp  discrete card.
 
Thanks,
Anshuman Gupta  
> 
> IMHO, still this patch is a valid fix. Perhaps, we can drop
> drm_close_driver() and use close().
> 
> + Anshuman to comment
> 
> - Bhanu
> 
> >
> > we are expecting i915 driver to be _unloaded_.
> >
> > Regards,
> > Kamil
> >
> >> +
> >> +	if (fd >= 0)
> >> +		drm_close_driver(fd);
> >>
> >>   	igt_kmsg(KMSG_INFO "Unloading i915\n");
> >>   	igt_assert_eq(igt_i915_driver_unload(),0);
> >> --
> >> 2.40.0
> >>