| Message ID | 20210503155748.1961781-13-jason@jlekstrand.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915/gem: ioctl clean-ups (v5) | expand |
On 03/05/2021 16:57, Jason Ekstrand wrote: > There's no sense in allowing userspace to create more engines than it > can possibly access via execbuf. > > Signed-off-by: Jason Ekstrand <jason@jlekstrand.net> > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> FWIW, again for the record, my advice is not to land this one. It makes no sense and it is actively disruptive for no benefit. Regards, Tvrtko > --- > drivers/gpu/drm/i915/gem/i915_gem_context.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c > index be42dc918ef6f..8e254d83d65f2 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c > @@ -1640,11 +1640,11 @@ set_engines(struct i915_gem_context *ctx, > return -EINVAL; > } > > - /* > - * Note that I915_EXEC_RING_MASK limits execbuf to only using the > - * first 64 engines defined here. > - */ > num_engines = (args->size - sizeof(*user)) / sizeof(*user->engines); > + /* RING_MASK has no shift so we can use it directly here */ > + if (num_engines > I915_EXEC_RING_MASK + 1) > + return -EINVAL; > + > set.engines = alloc_engines(num_engines); > if (!set.engines) > return -ENOMEM; >
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c index be42dc918ef6f..8e254d83d65f2 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c @@ -1640,11 +1640,11 @@ set_engines(struct i915_gem_context *ctx, return -EINVAL; } - /* - * Note that I915_EXEC_RING_MASK limits execbuf to only using the - * first 64 engines defined here. - */ num_engines = (args->size - sizeof(*user)) / sizeof(*user->engines); + /* RING_MASK has no shift so we can use it directly here */ + if (num_engines > I915_EXEC_RING_MASK + 1) + return -EINVAL; + set.engines = alloc_engines(num_engines); if (!set.engines) return -ENOMEM;