On Wed, May 27, 2020 at 02:54:13PM +0800, Xiaoming Ni wrote: > > On Tue, Mar 19, 2019 at 11:07:22AM +0800, Peter Xu wrote: > > Add a global sysctl knob "vm.unprivileged_userfaultfd" to control > > whether userfaultfd is allowed by unprivileged users. When this is > > set to zero, only privileged users (root user, or users with the > > CAP_SYS_PTRACE capability) will be able to use the userfaultfd > > syscalls. > > Hello Hi, Xiaoming, > I am a bit confused about this patch, can you help to answer it. > > Why the sysctl interface of fs/userfaultfd.c belongs to vm_table instead of > fs_table ? > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cefdca0a86be517bc390fc4541e3674b8e7803b0 Because I think it makes more sense to put the new key into where it suites better, irrelevant to which directory the variable is declared. To me, unprivileged_userfaultfd is definitely more suitable for vm rather than fs, because userfaultfd is really about memory management rather than file system. Thanks, -- Peter Xu
