Hi s390 maintainers, the base work to remove address space overrides using set_fs() has landed in linux-next through this tree: https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git/log/?h=base.set_fs and in addition to x86 and powerpc converted there, we have arm, arm64 and RISC-V conversion in progress. That means s390 is the only "tier 1" architecture still missing. Due to the special instructions for accessing the user space address space I don't really feel like doing the conversion myself, but it would be great if we could get s390 done for 5.10 as well. The rought TODO list is: (1) actually stop using set_fs in the zrcypt driver. I could prepare a crude untested patch for that if it helps. (2) implement the __get_user_nofault and __put_user_nofault helpers to safely access kernel memory. These should behave like get_user/put_user under set_fs(KERNEL_DS), but not actually manipulate any task state to do so (3) unselect CONFIG_SET_FS and remove all the code related to overriding the address space(3) unselect CONFIG_SET_FS and remove all the code related to overriding the address space limit
