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Release lock after encountering bogs row in vac_truncate_clog()

When vac_truncate_clog() encounters bogus datfrozenxid / datminmxid values, itreturns early. Unfortunately, until now, it did not releaseWrapLimitsVacuumLock. If the backend later tries to acquireWrapLimitsVacuumLock, the session / autovacuum worker hangs in anuncancellable way. Similarly, other sessions will hang waiting for thelock. However, if the backend holding the lock exited or errored out for somereason, the lock was released.The bug was introduced as a side effect of566372b.It is interesting that there are no production reports of this problem. Thatis likely due to a mix of bugs leading to bogus values having gotten lesscommon, process exit releasing locks and instances of hangs being hard todebug for "normal" users.Discussion:https://postgr.es/m/20230621221208.vhsqgduwfpzwxnpg@awork3.anarazel.de

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src/backend/commands
- vacuum.c

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`‎src/backend/commands/vacuum.c`

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Original file line number	Diff line number	Diff line change
`@@ -1893,12 +1893,16 @@ vac_truncate_clog(TransactionId frozenXID,`
`1893`	`1893`	`ereport(WARNING,`
`1894`	`1894`	`(errmsg("some databases have not been vacuumed in over 2 billion transactions"),`
`1895`	`1895`	`errdetail("You might have already suffered transaction-wraparound data loss.")));`
	`1896`	`+LWLockRelease(WrapLimitsVacuumLock);`
`1896`	`1897`	`return;`
`1897`	`1898`	`}`
`1898`	`1899`
`1899`	`1900`	`/* chicken out if data is bogus in any other way */`
`1900`	`1901`	`if (bogus)`
	`1902`	`+{`
	`1903`	`+LWLockRelease(WrapLimitsVacuumLock);`
`1901`	`1904`	`return;`
	`1905`	`+}`
`1902`	`1906`
`1903`	`1907`	`/*`
`1904`	`1908`	`* Advance the oldest value for commit timestamps before truncating, so`

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Commit83ecfa9

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`‎src/backend/commands/vacuum.c`

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