On Thu, Nov 21, 2024 at 02:00:46AM +0000, Matthew Wilcox wrote: > On Wed, Nov 20, 2024 at 02:10:44PM -0800, Shakeel Butt wrote: > > If 'struct vm_area_struct' is prone to performance issues due to > > cacheline misalignments then we should do something about the > > __randomize_layout tag for it. I imagine we can identify the fields > > which might be performance critical to be on same cacheline or different > > cacheline due to false sharing then we can divide the fields into > > different cacheline groups and fields can be __randomize_layout within > > the group. WDYT? > > Pretty sure the people who think security is more important than > performance are the only ones who randomize structs. I agree that I don't think we need concern ourselves with users of this setting for precisely this reason. I wouldn't want supporting this to cause difficulty for users who do not enable this when those who do aren't really concerned about the perf issues as Matthew says.