1587513 - TSan: data race involving Rust std::sync::mutex::Mutex

Status: RESOLVED FIXED

(Firefox Build System :: General, defect, P3)

Description

[Christian Holler (:decoder)]

Attachment: tsan-log-035f52aed442-std_sync_mutex.txt

See attachment for more information. Not sure what to make out of this one and where to put it. This seems to involve Rust mutexes. Right now I believe we don't pass the TSan flag into Rust code yet, but I don't know if this could be the reason for a report like this.

Comment 1

[Christian Holler (:decoder)]

I can confirm now that this race goes away when instrumenting the Rust code with TSan. So the fix here is to use RUSTFLAGS="-Zsanitizer=thread" for the TSan builds, which will require a Rust Nightly build that includes either of the following two PRs

• https://github.com/rust-lang/rust/pull/65241

or

• https://github.com/rust-lang/rust/pull/65497

to fix the duplicate sanitizer runtime issue.

Comment 2

[Aria Beingessner [:Gankra]]

Both of the linked PRs landed a long time ago and have ridden the trains to stable -- can we resolve this and remove the Mutex supression now?

Comment 3

[Christian Holler (:decoder)]

(In reply to Alexis Beingessner [:Gankra] from comment #2)

Both of the linked PRs landed a long time ago and have ridden the trains to stable -- can we resolve this and remove the Mutex supression now?

Remove it and do a try run. If that is green, we should be good.

Comment 4

[Mitchell Hentges [:mhentges] 🦀]

I'll gladly do the try run to verify that this can be closed :)
What "mutex suppression" is that that needs to be removed to test this? (Is this supposed to be related to another bug?)

Comment 5

[Aria Beingessner [:Gankra]]

Oh! They were removed in Bug 1671691.