On Wed, Feb 10, 2021 at 11:04:19AM -0500, Mathieu Desnoyers wrote: > Hi, > > While reconciling the lttng-modules writeback instrumentation with its counterpart > within the upstream Linux kernel, I notice that the following commit introduced in > 5.6 is present in stable branches 5.4 and 5.5, but is missing from LTS stable branches > for 4.4, 4.9, 4.14, 4.19: > > commit 68f23b89067fdf187763e75a56087550624fdbee > ("memcg: fix a crash in wb_workfn when a device disappears") > > Considering that this fix was CC'd to the stable mailing list, is there any > reason why it has not been integrated into those LTS branches ? Yes, it doesn't apply at all. If you think this is needed, I will gladly take backported and tested patches. But why do you think this is needed in older kernels? Have you hit this in real-life? thanks, greg k-h