I really like that as it’s self-documenting and anyone debugging it can see what is actually being used at a glance. > On Sep 20, 2020, at 09:15, Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Fri, Sep 18, 2020 at 02:45:25PM +0200, Christoph Hellwig wrote: >> Add a flag to force processing a syscall as a compat syscall. This is >> required so that in_compat_syscall() works for I/O submitted by io_uring >> helper threads on behalf of compat syscalls. > > Al doesn't like this much, but my suggestion is to introduce two new > opcodes -- IORING_OP_READV32 and IORING_OP_WRITEV32. The compat code > can translate IORING_OP_READV to IORING_OP_READV32 and then the core > code can know what that user pointer is pointing to.