Hi I have a question on the protection key in io_uring. Today, when a user thread enters the kernel through syscall, PKRU is preserved, and the kernel will respect the PKEY protection of memory. For example: sys_mprotect_pkey((void *)ptr, size, PROT_READ | PROT_WRITE, pkey); pkey_write_deny(pkey); <-- disable write access to pkey for this thread. ret = read(fd, ptr, 1); <-- this will fail in the kernel. I wonder what is the case for io_uring, since read is now async, will kthread have the user thread's PKUR ? In theory, it is possible, i.e. from io_uring_enter syscall. But I don't know the implementation details of io_uring, hence asking the expert in this list. Thanks! -Jeff
