This reverts commit1acca8bba3. As stated in the Godoc, this function is intended to check for presence of `apparmor_parser`. Changing this regressed the public API of containerd, and directly contradicts the way that this function is consumed inside of containerd itself: *fdfdc9bfc0/pkg/apparmor/apparmor.go (L20)*fdfdc9bfc0/pkg/cri/sbserver/helpers_linux.go (L85)*fdfdc9bfc0/pkg/cri/server/helpers_linux.go (L144)This has lead to a number of painful regressions and attempted fixes in Moby: * https://github.com/moby/moby/issues/44900 * https://github.com/moby/moby/pull/44902 * https://github.com/moby/moby/issues/44970 While reverting this late into the life of 1.6 and at the start of the life of 1.7 is likely painful, I think this is ultimately the best path to take, as containerd is subject to the same failure to start containers with an AppArmor kernel when `apparmor_parser` is missing as Moby. Signed-off-by: Bjorn Neergaard <bneergaard@mirantis.com>