Quoting Ram Moon, AnandX (2021-02-16 12:05:23) > Hi Chris, > > -----Original Message----- > From: dri-devel <dri-devel-boun...@lists.freedesktop.org> On Behalf Of Chris > Wilson > Sent: Monday, February 15, 2021 6:10 PM > To: Auld, Matthew <matthew.a...@intel.com>; Ram Moon, AnandX > <anandx.ram.m...@intel.com>; Surendrakumar Upadhyay, TejaskumarX > <tejaskumarx.surendrakumar.upadh...@intel.com>; Ursulin, Tvrtko > <tvrtko.ursu...@intel.com>; Jani Nikula <jani.nik...@linux.intel.com>; > dri-devel@lists.freedesktop.org; intel-...@lists.freedesktop.org > Subject: Re: [Intel-gfx] [PATCH] drm/i915/gem: Add a check for object size > for corner cases > > Quoting Ram Moon, AnandX (2021-02-15 12:29:17) > > Hi Chris, > > > > -----Original Message----- > > From: dri-devel <dri-devel-boun...@lists.freedesktop.org> On Behalf Of > > Chris Wilson > > Sent: Wednesday, February 10, 2021 4:15 PM > > To: Ram Moon, AnandX <anandx.ram.m...@intel.com>; Jani Nikula > > <jani.nik...@linux.intel.com>; Auld, Matthew <matthew.a...@intel.com>; > > Surendrakumar Upadhyay, TejaskumarX > > <tejaskumarx.surendrakumar.upadh...@intel.com>; Ursulin, Tvrtko > > <tvrtko.ursu...@intel.com>; dri-devel@lists.freedesktop.org; > > intel-...@lists.freedesktop.org > > Cc: Ram Moon, AnandX <anandx.ram.m...@intel.com> > > Subject: Re: [Intel-gfx] [PATCH] drm/i915/gem: Add a check for object > > size for corner cases > > > > Quoting Anand Moon (2021-02-10 07:59:29) > > > Add check for object size to return appropriate error -E2BIG or > > > -EINVAL to avoid WARM_ON and successful return for some testcase. > > > > No. You miss the point of having those warnings. We need to inspect the > > code to remove the last remaining "int pagenum", and then we can remove the > > GEM_WARN_ON((sz) >> PAGE_SHIFT > INT_MAX). These are not emitted for users, > > only for us to motivate us into finally fixing the code. > > -Chris > > > > Yes, I got your point these check are meant to catch up integer overflow. > > > > I have check with the IGT testcase case _gem_create_ and > > _gem_userptr_blits_ which fails pass size *-1ull << 32* left shift > > and *0~* which leads to integer overflow ie _negative_ size passed to > > create i915_gem_create via ioctl this leads to GM_WARN_ON. > > > > Can we drop these testcase so that we don't break the kernel ? > > The kernel rejects the ioctl with the expected errno. We leave a warning > purely for the benefit of CI, only when compiled for debugging and not by > default, so that we have a persistent reminder to do the code review. > What's broken? > -Chris > > All though the testcase return with appropriate error we observe kernel taint > see below.
Which is an intentional taint added for CI so that we get a warning and a visible bug so that we can allocate resources to _fix_ the underlying problems in the code. -Chris _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
