[Backport v3.4-branch] posix: eventfd: fix waking up poll() #59639
Conversation
Fix a regression introduced by commit e6eb0a7 ("posix: eventfd: revise locking, signaling, and allocation"), which was a complete rewrite stating that: The `wait_q` and `k_poll_signal` entries were removed from `struct eventfd` as they were unnecessary. In fact, `k_poll_signal` (both `read_sig` and `write_sig`) were used to wake-up blocking `poll()` invocation in another thread. This is no longer the case now, i.e. `poll(..., POLLIN)` does not return after calling `eventfd_write()` on the observed (polled) FD. Fix this regression by bringing back `read_sig` and `write_sig` to very similar state as it was before. Fixes: e6eb0a7 ("posix: eventfd: revise locking, signaling, and allocation") Signed-off-by: Marcin Niestroj <[email protected]> (cherry picked from commit 44d61bd)
Make sure that `poll(..., POLLIN)` executed from another thread returns when `eventfd_write()` is called. Test also the same with `poll(..., POLLOUT)` and `eventfd_read()` on eventfd with counter equal to `UINT64_MAX - 1`. Signed-off-by: Marcin Niestroj <[email protected]> (cherry picked from commit 2bc980f)
zephyrbot
added
Backport
|
@cfriedt can you check out the CI failures if you get a chance? |
|
@jgl-meta - the TLS issue can likely be fixed by a separate MbedTLS backport The aarch64 crashes are yet another backport, not sure which one will fix those, cc @carlocaione |
|
Any updates on this? It's a critical fix for a project I'm currently working on. |
Since the argument is a 32-bit unsigned int, all possible values satisfy the condition that intval < UINT64_MAX - 1. Remove the redundant conditional. Signed-off-by: Christopher Friedt <[email protected]>
@RicArch97 - this might still depend on the backport of #61455 (#61614) |
|
This pull request has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this pull request will automatically be closed in 14 days. Note, that you can always re-open a closed pull request at any time. |
|
@cfriedt Please look into this. |
I am already, thanks for the reminders. |
|
This pull request has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this pull request will automatically be closed in 14 days. Note, that you can always re-open a closed pull request at any time. |
Backport 2bc980f~2..2bc980f from #59505.
Fixes: #59577