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Michael Anthony Knyszek cc604130c8 [release-branch.go1.24] runtime: prevent mutual deadlock between GC stopTheWorld and suspendG
Almost everywhere we stop the world we casGToWaitingForGC to prevent
mutual deadlock with the GC trying to scan our stack. This historically
was only necessary if we weren't stopping the world to change the GC
phase, because what we were worried about was mutual deadlock with mark
workers' use of suspendG. And, they were the only users of suspendG.

In Go 1.22 this changed. The execution tracer began using suspendG, too.
This leads to the possibility of mutual deadlock between the execution
tracer and a goroutine trying to start or end the GC mark phase. The fix
is simple: make the stop-the-world calls for the GC also call
casGToWaitingForGC. This way, suspendG is guaranteed to make progress in
this circumstance, and once it completes, the stop-the-world can
complete as well.

We can take this a step further, though, and move casGToWaitingForGC
into stopTheWorldWithSema, since there's no longer really a place we can
afford to skip this detail.

While we're here, rename casGToWaitingForGC to casGToWaitingForSuspendG,
since the GC is now not the only potential source of mutual deadlock.

For #72740.
Fixes #74294.

Change-Id: I5e3739a463ef3e8173ad33c531e696e46260692f
Reviewed-on: https://go-review.googlesource.com/c/go/+/681501
Reviewed-by: Carlos Amedee <carlos@golang.org>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
(cherry picked from commit c6ac736288)
Reviewed-on: https://go-review.googlesource.com/c/go/+/684078
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2025-06-27 10:09:36 -07:00
.github .github: update language change proposal template 2024-08-08 19:02:29 +00:00
api debug/elf: adjust version API per issue discussion 2024-12-17 13:28:29 -08:00
doc [release-branch.go1.24] doc/godebug: mention GODEBUG=fips140 2025-02-19 13:59:08 -08:00
lib [release-branch.go1.24] lib/fips140: set inprocess.txt to v1.0.0 2025-05-28 10:21:28 -07:00
misc misc/wasm: move wasm runtime files to lib/wasm 2024-08-30 19:15:21 +00:00
src [release-branch.go1.24] runtime: prevent mutual deadlock between GC stopTheWorld and suspendG 2025-06-27 10:09:36 -07:00
test [release-branch.go1.24] cmd/compile/internal/ssa: fix PPC64 merging of (AND (S[RL]Dconst ...) 2025-06-11 20:49:41 -07:00
.gitattributes all: treat all files as binary, but check in .bat with CRLF 2020-06-08 15:31:43 +00:00
.gitignore runtime,internal: move runtime/internal/sys to internal/runtime/sys 2024-07-23 19:05:35 +00:00
codereview.cfg [release-branch.go1.24] update codereview.cfg for release-branch.go1.24 2024-12-06 21:58:36 +00:00
CONTRIBUTING.md doc: normalize proposal-process links 2023-03-29 22:00:27 +00:00
go.env cmd/go: additional doc-inspired tests and bug fixes 2023-06-06 19:18:46 +00:00
LICENSE LICENSE: update per Google Legal 2024-08-09 14:54:31 +00:00
PATENTS LICENSE: separate, change PATENTS text 2010-12-06 16:31:59 -05:00
README.md README: fix CC BY license name 2024-07-22 17:45:27 +00:00
SECURITY.md SECURITY.md: update the Reporting a Vulnerability link 2023-09-22 21:17:24 +00:00
VERSION [release-branch.go1.24] go1.24.4 2025-06-05 11:35:04 -07:00

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