On Fri 21-05-21 17:46:04, Andreas Gruenbacher wrote: > On Fri, May 21, 2021 at 5:23 PM Jan Kara <jack@xxxxxxx> wrote: > > On Thu 20-05-21 16:07:56, Andreas Gruenbacher wrote: > > > > So you probably need to add a new VM_FAULT_ > > > > return code that will behave like VM_FAULT_SIGBUS except it will not raise > > > > the signal. > > > > > > A new VM_FAULT_* flag might make the code easier to read, but I don't > > > know if we can have one. > > > > Well, this is kernel-internal API and there's still plenty of space in > > vm_fault_reason. > > That's in the context of the page fault. The other issue is how to > propagate that out through iov_iter_fault_in_readable -> > fault_in_pages_readable -> __get_user, for example. I don't think > there's much of a chance to get an additional error code out of > __get_user and __put_user. Yes, at that level we'd get EFAULT as in any other case. Really the only difference of the new VM_FAULT_ error code from a case of "standard" error and VM_FAULT_SIGBUS would be not raising the signal. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
