- Teach buffer pager about bogus pages. They should be silently skipped.
- Do not call into a vnode pager while leaving some pages from the same block as the current run, xbusy. This immediately deadlocks if pager needs to instantiate the buffer.
- Do not double-unbusy on error.
- Ensure that iodone() is called on erorrs from local pagers.
- Wait for all in-flight async io runs to complete before unwiring pages on error.
- expands comments explaining nuances which are hard to see even after re-reading the code
- add specific malloc type so that leaks are more easily seen that e.g. just wired or busy pages leak
- order headers alphabetically
- some style.
PR: 244713 [1, 2]
There are more issues, I limited the scope to interaction with the pagers.
Even there, there are more issues, most serious is explained in XXXKIB comment.
The patch passed stress2 sendfile subset, but I asked Peter for more run time.