On Wed, Apr 10, 2024 at 10:09:32PM -0700, Dixit, Ashutosh wrote: > On Wed, 10 Apr 2024 04:42:46 -0700, Ville Syrjälä wrote: > > > > On Tue, Apr 09, 2024 at 09:28:55PM -0700, Ashutosh Dixit wrote: > > > There are no hwmon selftests so there is no need to enable hwmon for > > > selftests. So enable hwmon only for real driver load. > > > > > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10366 > > > Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx> > > > > Why are we adding duct tape instead of fixing it properly? > > Yeah pretty much what I said here myself: > > https://patchwork.freedesktop.org/patch/588585/?series=132243&rev=1#comment_1071014 > > The issue has been difficult to root-cause. My last effort can be seen here: > > https://patchwork.freedesktop.org/patch/584859/?series=131630&rev=1#comment_1067888 > > Though Badal went further and saw that occasionaly the memory would get > freed first and hwmon would get unregistered as much as 2 seconds later, > which will cause the crash if anyone touched hwmon sysfs in those final 2 > seconds. So not sure what is causing that 2 second delay. Sounds like someone holding a sysfs file/etc. open. Should be trivial to do that by hand and see what happens. > > I am not sure if it is worth root-causing further. I am pretty sure if we > get rid of the devm_ stuff, that will fix the issue too. So if this patch > is not acceptable, we could just go that route (get rid of devm_ in hwmon). > > Thanks. > -- > Ashutosh > > > > --- > > > drivers/gpu/drm/i915/i915_driver.c | 16 ++++++++++++++-- > > > 1 file changed, 14 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c > > > index 9ee902d5b72c..6fa6d2c8109f 100644 > > > --- a/drivers/gpu/drm/i915/i915_driver.c > > > +++ b/drivers/gpu/drm/i915/i915_driver.c > > > @@ -94,6 +94,7 @@ > > > #include "i915_memcpy.h" > > > #include "i915_perf.h" > > > #include "i915_query.h" > > > +#include "i915_selftest.h" > > > #include "i915_suspend.h" > > > #include "i915_switcheroo.h" > > > #include "i915_sysfs.h" > > > @@ -589,6 +590,15 @@ static void i915_driver_hw_remove(struct drm_i915_private *dev_priv) > > > pci_disable_msi(pdev); > > > } > > > > > > +static bool is_selftest(void) > > > +{ > > > +#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) > > > + return i915_selftest.live || i915_selftest.perf || i915_selftest.mock; > > > +#else > > > + return false; > > > +#endif > > > +} > > > + > > > /** > > > * i915_driver_register - register the driver with the rest of the system > > > * @dev_priv: device private > > > @@ -624,7 +634,8 @@ static void i915_driver_register(struct drm_i915_private *dev_priv) > > > > > > intel_pxp_debugfs_register(dev_priv->pxp); > > > > > > - i915_hwmon_register(dev_priv); > > > + if (!is_selftest()) > > > + i915_hwmon_register(dev_priv); > > > > > > intel_display_driver_register(dev_priv); > > > > > > @@ -660,7 +671,8 @@ static void i915_driver_unregister(struct drm_i915_private *dev_priv) > > > for_each_gt(gt, dev_priv, i) > > > intel_gt_driver_unregister(gt); > > > > > > - i915_hwmon_unregister(dev_priv); > > > + if (!is_selftest()) > > > + i915_hwmon_unregister(dev_priv); > > > > > > i915_perf_unregister(dev_priv); > > > i915_pmu_unregister(dev_priv); > > > -- > > > 2.41.0 > > > > -- > > Ville Syrjälä > > Intel -- Ville Syrjälä Intel