[$] XFS, stable kernels, and -rc releases

Ever since the stable-update process was created, there have been questionsabout which patches are suitable for inclusion in those updates; usually,these discussions are driven by people who think that the criteria shouldbe more restrictive. A regression in the XFS filesystem that found its wayinto the 5.9.9stable update briefly rekindled this discussion. In one sense, there waslittle new ground covered in this iteration, but there was an interestingpoint raised about the relationship between stable updates and the mainlinekernel -rc releases.