| Message ID | 20200923044054.5653-1-steven.t.hampson@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix NULL pointer found by static analysis | expand |
Quoting Steve Hampson (2020-09-23 05:40:54) > A static analysis tool has reveiled a NULL pointer error in > __i915_gem_object_lock. This appears to be correct as many calls > pass a NULL into the ww parameter. > > Signed-off-by: Steve Hampson <steven.t.hampson@intel.com> > --- > drivers/gpu/drm/i915/gem/i915_gem_object.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h > index d46db8d8f38e..9b18ead42991 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h > +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h > @@ -126,7 +126,7 @@ static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj, > if (ret == -EALREADY) > ret = 0; > > - if (ret == -EDEADLK) > + if (ret == -EDEADLK && ww) EDEADLK is predicated by ww already. -Chris
On Wed, 23 Sep 2020, Chris Wilson <chris@chris-wilson.co.uk> wrote: > Quoting Steve Hampson (2020-09-23 05:40:54) >> A static analysis tool has reveiled a NULL pointer error in >> __i915_gem_object_lock. This appears to be correct as many calls >> pass a NULL into the ww parameter. >> >> Signed-off-by: Steve Hampson <steven.t.hampson@intel.com> >> --- >> drivers/gpu/drm/i915/gem/i915_gem_object.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h >> index d46db8d8f38e..9b18ead42991 100644 >> --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h >> +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h >> @@ -126,7 +126,7 @@ static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj, >> if (ret == -EALREADY) >> ret = 0; >> >> - if (ret == -EDEADLK) >> + if (ret == -EDEADLK && ww) > > EDEADLK is predicated by ww already. The hard part is that neither the analyzer nor a human who doesn't know how dma_resv_lock* work can easily deduce that. :( BR, Jani.
Never mind. This is a false positive. -----Original Message----- From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Steve Hampson Sent: Tuesday, September 22, 2020 9:41 PM To: intel-gfx@lists.freedesktop.org Subject: [Intel-gfx] [PATCH] Fix NULL pointer found by static analysis A static analysis tool has reveiled a NULL pointer error in __i915_gem_object_lock. This appears to be correct as many calls pass a NULL into the ww parameter. Signed-off-by: Steve Hampson <steven.t.hampson@intel.com> --- drivers/gpu/drm/i915/gem/i915_gem_object.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h index d46db8d8f38e..9b18ead42991 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -126,7 +126,7 @@ static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj, if (ret == -EALREADY) ret = 0; - if (ret == -EDEADLK) + if (ret == -EDEADLK && ww) ww->contended = obj; return ret; -- 2.21.0
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h index d46db8d8f38e..9b18ead42991 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -126,7 +126,7 @@ static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj, if (ret == -EALREADY) ret = 0; - if (ret == -EDEADLK) + if (ret == -EDEADLK && ww) ww->contended = obj; return ret;
A static analysis tool has reveiled a NULL pointer error in __i915_gem_object_lock. This appears to be correct as many calls pass a NULL into the ww parameter. Signed-off-by: Steve Hampson <steven.t.hampson@intel.com> --- drivers/gpu/drm/i915/gem/i915_gem_object.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)