x/net/internal/quic: `TestUDPSourceUnspecified/udp6/udp/unspec` consistently timing out on several platforms since CL 565255

[bcmills]

Go version

b27d02c

Output of go env in your module/workspace:

N/A

What did you do?

Check https://build.golang.org/?repo=golang.org%2fx%2fnet.

What did you see happen?

https://build.golang.org/log/a865aebbfef6c496482a607fd16a61a0d4ce9a7d:

panic: test timed out after 10m0s
running tests:
	TestUDPSourceUnspecified (9m59s)
	TestUDPSourceUnspecified/udp6/udp/unspec (9m59s)

goroutine 1692 [running]:
testing.(*M).startAlarm.func1()
	/tmp/workdir/go/src/testing/testing.go:2366 +0x385
created by time.goFunc
	/tmp/workdir/go/src/time/sleep.go:177 +0x2d

goroutine 1 [chan receive, 9 minutes]:
testing.(*T).Run(0xc00019e1a0, {0x7fabc4?, 0x7d19625000f9a00?}, 0x82ea60)
	/tmp/workdir/go/src/testing/testing.go:1750 +0x3ab
testing.runTests.func1(0xc00019e1a0)
	/tmp/workdir/go/src/testing/testing.go:2161 +0x37
testing.tRunner(0xc00019e1a0, 0xc0000f9b28)
	/tmp/workdir/go/src/testing/testing.go:1689 +0xfb
testing.runTests(0xc0001b6000, {0xabc0e0, 0x130, 0x130}, {0x9004a?, 0xc0000f9bb8?, 0xac15a0?})
	/tmp/workdir/go/src/testing/testing.go:2159 +0x445
testing.(*M).Run(0xc0001a8000)
	/tmp/workdir/go/src/testing/testing.go:2027 +0x68b
golang.org/x/net/internal/quic.TestMain(0xc000050708?)
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/main_test.go:19 +0x31
main.main()
	_testmain.go:671 +0x195

goroutine 34 [syscall, 10 minutes]:
os/signal.signal_recv()
	/tmp/workdir/go/src/runtime/sigqueue.go:152 +0x29
os/signal.loop()
	/tmp/workdir/go/src/os/signal/signal_unix.go:23 +0x13
created by os/signal.Notify.func1.1 in goroutine 1
	/tmp/workdir/go/src/os/signal/signal.go:151 +0x1f

goroutine 35 [chan receive, 10 minutes]:
golang.org/x/net/internal/quic.init.1.func1()
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/gotraceback_test.go:22 +0x19
created by golang.org/x/net/internal/quic.init.1 in goroutine 1
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/gotraceback_test.go:21 +0x98

goroutine 1673 [IO wait, 9 minutes]:
internal/poll.runtime_pollWait(0x2d52fa920, 0x72)
	/tmp/workdir/go/src/runtime/netpoll.go:345 +0x85
internal/poll.(*pollDesc).wait(0xc000458100?, 0xc0000ec600?, 0x0)
	/tmp/workdir/go/src/internal/poll/fd_poll_runtime.go:84 +0x27
internal/poll.(*pollDesc).waitRead(...)
	/tmp/workdir/go/src/internal/poll/fd_poll_runtime.go:89
internal/poll.(*FD).ReadMsgInet4(0xc000458100, {0xc0000ec600, 0x5c0, 0x5c0}, {0x0, 0x0, 0x0}, 0x0, 0xc000061e28)
	/tmp/workdir/go/src/internal/poll/fd_unix.go:328 +0x323
net.(*netFD).readMsgInet4(0xc000458100, {0xc0000ec600?, 0x2c96a2968?, 0xc0003c42a0?}, {0x0?, 0x3?, 0x4f6180?}, 0xa35510?, 0xa9e4a0?)
	/tmp/workdir/go/src/net/fd_posix.go:84 +0x31
net.(*UDPConn).readMsg(0x60?, {0xc0000ec600?, 0xc000213601?, 0xc0002136e0?}, {0x0?, 0x476000?, 0x7?})
	/tmp/workdir/go/src/net/udpsock_posix.go:101 +0x170
net.(*UDPConn).ReadMsgUDPAddrPort(0xc000744068, {0xc0000ec600?, 0x471525?, 0x1b64dec500213758?}, {0x0?, 0x4f5e73?, 0xc00019ca40?})
	/tmp/workdir/go/src/net/udpsock.go:203 +0x3e
golang.org/x/net/internal/quic.(*netUDPConn).Read(0xc000744070, 0xc000061fb8)
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_other.go:46 +0xc5
golang.org/x/net/internal/quic.runUDPTest.func1.2()
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:154 +0x6d
created by golang.org/x/net/internal/quic.runUDPTest.func1 in goroutine 1672
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:152 +0x3c8

goroutine 1689 [chan receive, 9 minutes]:
testing.(*T).Run(0xc00019e9c0, {0xc0002acec0?, 0xc000238ef8?}, 0xc000012150)
	/tmp/workdir/go/src/testing/testing.go:1750 +0x3ab
golang.org/x/net/internal/quic.runUDPTest(0xc00019e9c0, 0x82f148)
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:123 +0xa5
golang.org/x/net/internal/quic.TestUDPSourceUnspecified(0xc00019e9c0?)
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:20 +0x1a
testing.tRunner(0xc00019e9c0, 0x82ea60)
	/tmp/workdir/go/src/testing/testing.go:1689 +0xfb
created by testing.(*T).Run in goroutine 1
	/tmp/workdir/go/src/testing/testing.go:1742 +0x390

goroutine 1672 [chan receive, 9 minutes]:
golang.org/x/net/internal/quic.TestUDPSourceUnspecified.func1(0xc000282000, {0xc000744060, 0xc000744070, {{{0x0, 0x1}, 0xc00009c0a8}, 0x78dd}, 0xc000360480})
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:28 +0x1ba
golang.org/x/net/internal/quic.runUDPTest.func1(0xc000282000)
	/tmp/workdir/gopath/src/golang.org/x/net/internal/quic/udp_test.go:165 +0x50f
testing.tRunner(0xc000282000, 0xc000012150)
	/tmp/workdir/go/src/testing/testing.go:1689 +0xfb
created by testing.(*T).Run in goroutine 1689
	/tmp/workdir/go/src/testing/testing.go:1742 +0x390
FAIL	golang.org/x/net/internal/quic	600.106s

What did you expect to see?

All tests passing.

(attn @neild @jba)

[bcmills]

This failure mode affects the openbsd, dragonfly, js, and wasip1 ports — which seems extra strange because it's the same failure mode on a couple of BSDs and a completely separate in-process fake network stack. 😅

[gopherbot]

Change https://go.dev/cl/566098 mentions this issue: quic: temporarily disable networking tests failing on various platforms

[gopherbot]

Change https://go.dev/cl/566296 mentions this issue: quic: fix UDP on big-endian Linux, tests on various architectures