On Thu, 2022-02-03 at 14:42 -0800, Dave Hansen wrote: > This is a good start for the selftest. But, it would be really nice > to > see a few additional smoke tests in here that are independent of the > library support. Sure. I had actually included this just because the "adding a syscall" docs said to make sure to include a test for the syscall. There are some other tests that were being planned as a follow up. > > For instance, it would be nice to have tests that: > > 1. Write to the shadow stack with normal instructions (and recover > from > the inevitable SEGV). Make sure the siginfo looks like we expect. > 2. Corrupt the regular stack, or maybe just use a retpoline > do induce a shadow stack exception. Ditto on checking the siginfo > 3. Do enough CALLs that will likely trigger a fault and an on-demand > shadow stack page allocation. > > That will test the *basics* and should be pretty simple to write. Most of this already exists in the private tests. I'll combine it into a single selftest. Having wrss now nicely made it a bit easier because those writes are treated as shadow stack accesses, so we can do these operations directly without too much calling acrobatics. Thanks, Rick
