* Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> [240202 15:37]: > On Fri, 2 Feb 2024 at 11:32, Theo de Raadt <deraadt@xxxxxxxxxxx> wrote: > > > > Unix system calls must be atomic. > > > > They either return an error, and that is a promise they made no changes. > > That's actually not true, and never has been. ... > > In the specific case of mseal(), I suspect there are very few reasons > ever *not* to be atomic, so in this particular context atomicity is > likely always something that should be guaranteed. But I just wanted > to point out that it's most definitely not a black-and-white issue in > the general case. There will be a larger performance cost to checking up front without allowing the partial completion. I don't expect these to be high, but it's something to keep in mind if we are okay with the flexibility and less atomic operation. Thanks, Liam
