Fix in-place tablespace crashes: session lock leak and segment SIGSEGV#1628
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yjhjstz merged 3 commits intoapache:mainfrom Mar 18, 2026
Merged
Fix in-place tablespace crashes: session lock leak and segment SIGSEGV#1628yjhjstz merged 3 commits intoapache:mainfrom
yjhjstz merged 3 commits intoapache:mainfrom
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Pull request overview
Fixes Greenplum in-place tablespace edge cases that could crash backends/segments or emit misleading logs, and addresses a utility-mode session lock leak that caused TAP recovery test failures.
Changes:
- Release movedb session-level lock at commit time for utility-mode backends to prevent lock leakage/assertion failure at process exit.
- Prevent QE SIGSEGV by treating a NULL
CreateTableSpaceStmt->locationas empty string for in-place tablespaces. - Suppress expected
readlink()EINVALnoise when dropping in-place tablespaces (wherepg_tblspc/<oid>is a directory, not a symlink).
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| src/backend/commands/tablespace.c | Guard against NULL stmt->location for in-place tablespaces; avoid logging expected readlink(EINVAL) for in-place drop paths. |
| src/backend/access/transam/xact.c | Release movedb session lock on commit in GP_ROLE_UTILITY to prevent session lock leaks in standalone/utility backends. |
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reshke
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Ohhh.. yes, this is clear oversight introduced in recent ported changes.
Somehow this worked in my by-hand hand (I also thought CI was reliable here)
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Linking for cross-reference #1585 |
x4m
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Lets rebase & merge |
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Another rebase after 11c5515 |
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When CREATE TABLESPACE ... LOCATION '' is dispatched from QD to QE, the serialization converts the empty string to NULL. On the segment, pstrdup(stmt->location) crashes with SIGSEGV because stmt->location is NULL. Add a NULL guard to treat NULL the same as empty string, preserving in-place tablespace semantics. Fixes apache#1627
movedb() acquires a session-level AccessExclusiveLock on the database
via MoveDbSessionLockAcquire(). The release in CommitTransaction()
only checked for GP_ROLE_DISPATCH and IS_SINGLENODE(), missing
GP_ROLE_UTILITY. This caused the lock to leak in standalone backends
(e.g. TAP tests), triggering a proc.c assertion failure at exit:
FailedAssertion("SHMQueueEmpty(&(MyProc->myProcLocks[i]))")
Add GP_ROLE_UTILITY to the release condition.
Also fix a spurious "could not read symbolic link" log message when
dropping in-place tablespaces: readlink() on a directory returns
EINVAL, which is expected and can be safely skipped.
Fixes apache#1626
Two fixes:
- Use TestLib::slurp_file instead of PostgreSQL::Test::Utils::slurp_file
in adjust_conf(). PostgresNode.pm only imports TestLib, not
PostgreSQL::Test::Utils, so the latter is undefined and causes
t/101_restore_point_and_startup_pause to fail.
- Replace cp with install -m 644 in enable_archiving() archive_command.
coreutils 8.32 (Rocky 8, Ubuntu 22.04) uses copy_file_range() in cp
which crashes on Docker overlayfs. install does not use
copy_file_range(), avoiding the crash.
Also add ic-recovery test suite to rocky8 and deb CI pipelines.
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Summary
ALTER DATABASE SET TABLESPACEfor utility-mode backends, which caused assertion failure in TAP test033_replay_tsp_drops.plCREATE TABLESPACE ... LOCATION ''Root Cause
Session lock leak (Issue #1626):
movedb()acquires a session-levelAccessExclusiveLockviaMoveDbSessionLockAcquire(). The release inCommitTransaction()only checkedGp_role == GP_ROLE_DISPATCH || IS_SINGLENODE(), missingGP_ROLE_UTILITY. Standalone backends (TAP tests, pg_basebackup recovery) leaked the lock, triggeringproc.c:1067assertion at exit.Segment SIGSEGV (Issue #1627): When
CREATE TABLESPACE ... LOCATION ''is dispatched to segments, serialization converts the empty string to NULL.pstrdup(NULL)crashes the segment process.Fix
Gp_role == GP_ROLE_UTILITYto the session lock release condition inCommitTransaction()stmt->locationinCreateTableSpace()readlink()EINVAL error for in-place tablespace directories (they are directories, not symlinks)Test Plan
src/test/recovery/t/033_replay_tsp_drops.plpasses (previously crashed with assertion failure)CREATE TABLESPACE ... LOCATION ''on MPP cluster does not crash segmentsFixes #1626
Fixes #1627