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* Allow DSM allocation to be interrupted.Thomas Munro2018-09-18
| | | | | | | | | | | | | | | | Chris Travers reported that the startup process can repeatedly try to cancel a backend that is in a posix_fallocate()/EINTR loop and cause it to loop forever. Teach the retry loop to give up if an interrupt is pending. Don't actually check for interrupts in that loop though, because a non-local exit would skip some clean-up code in the caller. Back-patch to 9.4 where DSM was added (and posix_fallocate() was later back-patched). Author: Chris Travers Reviewed-by: Ildar Musin, Murat Kabilov, Oleksii Kliukin Tested-by: Oleksii Kliukin Discussion: https://postgr.es/m/CAN-RpxB-oeZve_J3SM_6%3DHXPmvEG%3DHX%2B9V9pi8g2YR7YW0rBBg%40mail.gmail.com
* Fix failure with initplans used conditionally during EvalPlanQual rechecks.Tom Lane2018-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The EvalPlanQual machinery assumes that any initplans (that is, uncorrelated sub-selects) used during an EPQ recheck would have already been evaluated during the main query; this is implicit in the fact that execPlan pointers are not copied into the EPQ estate's es_param_exec_vals. But it's possible for that assumption to fail, if the initplan is only reached conditionally. For example, a sub-select inside a CASE expression could be reached during a recheck when it had not been previously, if the CASE test depends on a column that was just updated. This bug is old, appearing to date back to my rewrite of EvalPlanQual in commit 9f2ee8f28, but was not detected until Kyle Samson reported a case. To fix, force all not-yet-evaluated initplans used within the EPQ plan subtree to be evaluated at the start of the recheck, before entering the EPQ environment. This could be inefficient, if such an initplan is expensive and goes unused again during the recheck --- but that's piling one layer of improbability atop another. It doesn't seem worth adding more complexity to prevent that, at least not in the back branches. It was convenient to use the new-in-v11 ExecEvalParamExecParams function to implement this, but I didn't like either its name or the specifics of its API, so revise that. Back-patch all the way. Rather than rewrite the patch to avoid depending on bms_next_member() in the oldest branches, I chose to back-patch that function into 9.4 and 9.3. (This isn't the first time back-patches have needed that, and it exhausted my patience.) I also chose to back-patch some test cases added by commits 71404af2a and 342a1ffa2 into 9.4 and 9.3, so that the 9.x versions of eval-plan-qual.spec are all the same. Andrew Gierth diagnosed the problem and contributed the added test cases, though the actual code changes are by me. Discussion: https://postgr.es/m/A033A40A-B234-4324-BE37-272279F7B627@tripadvisor.com
* Attach FPI to the first record after full_page_writes is turned on.Amit Kapila2018-09-13
| | | | | | | | | | | | | | | | XLogInsert fails to attach a required FPI to the first record after full_page_writes is turned on by the last checkpoint. This bug got introduced in 9.5 due to code rearrangement in commits 2c03216d83 and 2076db2aea. Fix it by ensuring that XLogInsertRecord performs a recomputation when the given record is generated with FPW as off but found that the flag has been turned on while actually inserting the record. Reported-by: Kyotaro Horiguchi Author: Kyotaro Horiguchi Reviewed-by: Amit Kapila Backpatch-through: 9.5 where this problem was introduced Discussion: https://postgr.es/m/20180420.151043.74298611.horiguchi.kyotaro@lab.ntt.co.jp
* Repair bug in regexp split performance improvements.Andrew Gierth2018-09-12
| | | | | | | | | | | | | | | | Commit c8ea87e4b introduced a temporary conversion buffer for substrings extracted during regexp splits. Unfortunately the code that sized it was failing to ignore the effects of ignored degenerate regexp matches, so for regexp_split_* calls it could under-size the buffer in such cases. Fix, and add some regression test cases (though those will only catch the bug if run in a multibyte encoding). Backpatch to 9.3 as the faulty code was. Thanks to the PostGIS project, Regina Obe and Paul Ramsey for the report (via IRC) and assistance in analysis. Patch by me.
* Fix past pd_upper write in ginRedoRecompress()Alexander Korotkov2018-09-09
| | | | | | | | | | | | | | | | ginRedoRecompress() replays actions over compressed segments of posting list in-place. However, it might lead to write past pg_upper, because intermediate state during playing the changes can take more space than both original state and final state. This commit fixes that by refuse from in-place modification. Instead page tail is copied once modification is started, and then it's used as the source of original segments. Backpatch to 9.4 where posting list compression was introduced. Reported-by: Sivasubramanian Ramasubramanian Discussion: https://postgr.es/m/1536091151804.6588%40amazon.com Author: Alexander Korotkov based on patch from and ideas by Sivasubramanian Ramasubramanian Review: Sivasubramanian Ramasubramanian Backpatch-through: 9.4
* Save/restore SPI's global variables in SPI_connect() and SPI_finish().Tom Lane2018-09-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes two sources of interference between nominally independent functions when one SPI-using function calls another, perhaps without knowing that it does so. Chapman Flack pointed out that xml.c's query_to_xml_internal() expects SPI_tuptable and SPI_processed to stay valid across datatype output function calls; but it's possible that such a call could involve re-entrant use of SPI. It seems likely that there are similar hazards elsewhere, if not in the core code then in third-party SPI users. Previously SPI_finish() reset SPI's API globals to zeroes/nulls, which would typically make for a crash in such a situation. Restoring them to the values they had at SPI_connect() seems like a considerably more useful behavior, and it still meets the design goal of not leaving any dangling pointers to tuple tables of the function being exited. Also, cause SPI_connect() to reset these variables to zeroes/nulls after saving them. This prevents interference in the opposite direction: it's possible that a SPI-using function that's only ever been tested standalone contains assumptions that these variables start out as zeroes. That was the case as long as you were the outermost SPI user, but not so much for an inner user. Now it's consistent. Report and fix suggestion by Chapman Flack, actual patch by me. Back-patch to all supported branches. Discussion: https://postgr.es/m/9fa25bef-2e4f-1c32-22a4-3ad0723c4a17@anastigmatix.net
* Limit depth of forced recursion for CLOBBER_CACHE_RECURSIVELY.Tom Lane2018-09-07
| | | | | | | | | | | | It's somewhat surprising that we got away with this before. (Actually, since nobody tests this routinely AFAIK, it might've been broken for awhile. But it's definitely broken in the wake of commit f868a8143.) It seems sufficient to limit the forced recursion to a small number of levels. Back-patch to all supported branches, like the preceding patch. Discussion: https://postgr.es/m/12259.1532117714@sss.pgh.pa.us
* Fix longstanding recursion hazard in sinval message processing.Tom Lane2018-09-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | LockRelationOid and sibling routines supposed that, if our session already holds the lock they were asked to acquire, they could skip calling AcceptInvalidationMessages on the grounds that we must have already read any remote sinval messages issued against the relation being locked. This is normally true, but there's a critical special case where it's not: processing inside AcceptInvalidationMessages might attempt to access system relations, resulting in a recursive call to acquire a relation lock. Hence, if the outer call had acquired that same system catalog lock, we'd fall through, despite the possibility that there's an as-yet-unread sinval message for that system catalog. This could, for example, result in failure to access a system catalog or index that had just been processed by VACUUM FULL. This is the explanation for buildfarm failures we've been seeing intermittently for the past three months. The bug is far older than that, but commits a54e1f158 et al added a new recursion case within AcceptInvalidationMessages that is apparently easier to hit than any previous case. To fix this, we must not skip calling AcceptInvalidationMessages until we have *finished* a call to it since acquiring a relation lock, not merely acquired the lock. (There's already adequate logic inside AcceptInvalidationMessages to deal with being called recursively.) Fortunately, we can implement that at trivial cost, by adding a flag to LOCALLOCK hashtable entries that tracks whether we know we have completed such a call. There is an API hazard added by this patch for external callers of LockAcquire: if anything is testing for LOCKACQUIRE_ALREADY_HELD, it might be fooled by the new return code LOCKACQUIRE_ALREADY_CLEAR into thinking the lock wasn't already held. This should be a fail-soft condition, though, unless something very bizarre is being done in response to the test. Also, I added an additional output argument to LockAcquireExtended, assuming that that probably isn't called by any outside code given the very limited usefulness of its additional functionality. Back-patch to all supported branches. Discussion: https://postgr.es/m/12259.1532117714@sss.pgh.pa.us
* Fix initial sync of slot parent directory when restoring statusMichael Paquier2018-09-02
| | | | | | | | | | | | | | | | At the beginning of recovery, information from replication slots is recovered from disk to memory. In order to ensure the durability of the information, the status file as well as its parent directory are synced. It happens that the sync on the parent directory was done directly using the status file path, which is logically incorrect, and the current code has been doing a sync on the same object twice in a row. Reported-by: Konstantin Knizhnik Diagnosed-by: Konstantin Knizhnik Author: Michael Paquier Discussion: https://postgr.es/m/9eb1a6d5-b66f-2640-598d-c5ea46b8f68a@postgrespro.ru Backpatch-through: 9.4-
* Avoid using potentially-under-aligned page buffers.Tom Lane2018-09-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a project policy against using plain "char buf[BLCKSZ]" local or static variables as page buffers; preferred style is to palloc or malloc each buffer to ensure it is MAXALIGN'd. However, that policy's been ignored in an increasing number of places. We've apparently got away with it so far, probably because (a) relatively few people use platforms on which misalignment causes core dumps and/or (b) the variables chance to be sufficiently aligned anyway. But this is not something to rely on. Moreover, even if we don't get a core dump, we might be paying a lot of cycles for misaligned accesses. To fix, invent new union types PGAlignedBlock and PGAlignedXLogBlock that the compiler must allocate with sufficient alignment, and use those in place of plain char arrays. I used these types even for variables where there's no risk of a misaligned access, since ensuring proper alignment should make kernel data transfers faster. I also changed some places where we had been palloc'ing short-lived buffers, for coding style uniformity and to save palloc/pfree overhead. Since this seems to be a live portability hazard (despite the lack of field reports), back-patch to all supported versions. Patch by me; thanks to Michael Paquier for review. Discussion: https://postgr.es/m/1535618100.1286.3.camel@credativ.de
* Ignore server-side delays when enforcing wal_sender_timeout.Noah Misch2018-08-31
| | | | | | | | | | | Healthy clients of servers having poor I/O performance, such as buildfarm members hamster and tern, saw unexpected timeouts. That disagreed with documentation. This fix adds one gettimeofday() call whenever ProcessRepliesIfAny() finds no client reply messages. Back-patch to 9.4; the bug's symptom is rare and mild, and the code all moved between 9.3 and 9.4. Discussion: https://postgr.es/m/20180826034600.GA1105084@rfd.leadboat.com
* Ensure correct minimum consistent point on standbysMichael Paquier2018-08-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Startup process has improved its calculation of incorrect minimum consistent point in 8d68ee6, which ensures that all WAL available gets replayed when doing crash recovery, and has introduced an incorrect calculation of the minimum recovery point for non-startup processes, which can cause incorrect page references on a standby when for example the background writer flushed a couple of pages on-disk but was not updating the control file to let a subsequent crash recovery replay to where it should have. The only case where this has been reported to be a problem is when a standby needs to calculate the latest removed xid when replaying a btree deletion record, so one would need connections on a standby that happen just after recovery has thought it reached a consistent point. Using a background worker which is started after the consistent point is reached would be the easiest way to get into problems if it connects to a database. Having clients which attempt to connect periodically could also be a problem, but the odds of seeing this problem are much lower. The fix used is pretty simple, as the idea is to give access to the minimum recovery point written in the control file to non-startup processes so as they use a reference, while the startup process still initializes its own references of the minimum consistent point so as the original problem with incorrect page references happening post-promotion with a crash do not show up. Reported-by: Alexander Kukushkin Diagnosed-by: Alexander Kukushkin Author: Michael Paquier Reviewed-by: Kyotaro Horiguchi, Alexander Kukushkin Discussion: https://postgr.es/m/153492341830.1368.3936905691758473953@wrigleys.postgresql.org Backpatch-through: 9.3
* Stop bgworkers during fast shutdown with postmaster in startup phaseMichael Paquier2018-08-29
| | | | | | | | | | | | | | When a postmaster gets into its phase PM_STARTUP, it would start background workers using BgWorkerStart_PostmasterStart mode immediately, which would cause problems for a fast shutdown as the postmaster forgets to send SIGTERM to already-started background workers. With smart and immediate shutdowns, this correctly happened, and fast shutdown is the only mode missing the shot. Author: Alexander Kukushkin Reviewed-by: Michael Paquier Discussion: https://postgr.es/m/CAFh8B=mvnD8+DZUfzpi50DoaDfZRDfd7S=gwj5vU9GYn8UvHkA@mail.gmail.com Backpatch-through: 9.5
* Avoid quadratic slowdown in regexp match/split functions.Andrew Gierth2018-08-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | regexp_matches, regexp_split_to_table and regexp_split_to_array all work by compiling a list of match positions as character offsets (NOT byte positions) in the source string. Formerly, they then used text_substr to extract the matched text; but in a multi-byte encoding, that counts the characters in the string, and the characters needed to reach the starting byte position, on every call. Accordingly, the performance degraded as the product of the input string length and the number of match positions, such that splitting a string of a few hundred kbytes could take many minutes. Repair by keeping the wide-character copy of the input string available (only in the case where encoding_max_length is not 1) after performing the match operation, and extracting substrings from that instead. This reduces the complexity to being linear in the number of result bytes, discounting the actual regexp match itself (which is not affected by this patch). In passing, remove cleanup using retail pfree() which was obsoleted by commit ff428cded (Feb 2008) which made cleanup of SRF multi-call contexts automatic. Also increase (to ~134 million) the maximum number of matches and provide an error message when it is reached. Backpatch all the way because this has been wrong forever. Analysis and patch by me; review by Kaiting Chen. Discussion: https://postgr.es/m/87pnyn55qh.fsf@news-spur.riddles.org.uk see also https://postgr.es/m/87lg996g4r.fsf@news-spur.riddles.org.uk
* Make syslogger more robust against failures in opening CSV log files.Tom Lane2018-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The previous coding figured it'd be good enough to postpone opening the first CSV log file until we got a message we needed to write there. This is unsafe, though, because if the open fails we end up in infinite recursion trying to report the failure. Instead make the CSV log file management code look as nearly as possible like the longstanding logic for the stderr log file. In particular, open it immediately at postmaster startup (if enabled), or when we get a SIGHUP in which we find that log_destination has been changed to enable CSV logging. It seems OK to fail if a postmaster-start-time open attempt fails, as we've long done for the stderr log file. But we can't die if we fail to open a CSV log file during SIGHUP, so we're still left with a problem. In that case, write any output meant for the CSV log file to the stderr log file. (This will also cover race-condition cases in which backends send CSV log data before or after we have the CSV log file open.) This patch also fixes an ancient oversight that, if CSV logging was turned off during a SIGHUP, we never actually closed the last CSV log file. In passing, remember to reset whereToSendOutput = DestNone during syslogger start, since (unlike all other postmaster children) it's forked before the postmaster has done that. This made for a platform-dependent difference in error reporting behavior between the syslogger and other children: except on Windows, it'd report problems to the original postmaster stderr as well as the normal error log file(s). It's barely possible that that was intentional at some point; but it doesn't seem likely to be desirable in production, and the platform dependency definitely isn't desirable. Per report from Alexander Kukushkin. It's been like this for a long time, so back-patch to all supported branches. Discussion: https://postgr.es/m/CAFh8B==iLUD_gqC-dAENS0V+kVrCeGiKujtKqSQ7++S-caaChw@mail.gmail.com
* Fix lexing of standard multi-character operators in edge cases.Andrew Gierth2018-08-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits c6b3c939b (which fixed the precedence of >=, <=, <> operators) and 865f14a2d (which added support for the standard => notation for named arguments) created a class of lexer tokens which look like multi-character operators but which have their own token IDs distinct from Op. However, longest-match rules meant that following any of these tokens with another operator character, as in (1<>-1), would cause them to be incorrectly returned as Op. The error here isn't immediately obvious, because the parser would usually still find the correct operator via the Op token, but there were more subtle problems: 1. If immediately followed by a comment or +-, >= <= <> would be given the old precedence of Op rather than the correct new precedence; 2. If followed by a comment, != would be returned as Op rather than as NOT_EQUAL, causing it not to be found at all; 3. If followed by a comment or +-, the => token for named arguments would be lexed as Op, causing the argument to be mis-parsed as a simple expression, usually causing an error. Fix by explicitly checking for the operators in the {operator} code block in addition to all the existing special cases there. Backpatch to 9.5 where the problem was introduced. Analysis and patch by me; review by Tom Lane. Discussion: https://postgr.es/m/87va851ppl.fsf@news-spur.riddles.org.uk
* Reduce an unnecessary O(N^3) loop in lexer.Andrew Gierth2018-08-23
| | | | | | | | | | | | The lexer's handling of operators contained an O(N^3) hazard when dealing with long strings of + or - characters; it seems hard to prevent this case from being O(N^2), but the additional N multiplier was not needed. Backpatch all the way since this has been there since 7.x, and it presents at least a mild hazard in that trying to do Bind, PREPARE or EXPLAIN on a hostile query could take excessive time (without honouring cancels or timeouts) even if the query was never executed.
* Fix set of NLS translation issuesMichael Paquier2018-08-21
| | | | | | | | | | | | | | | | While monitoring the code, a couple of issues related to string translation has showed up: - Some routines for auto-updatable views return an error string, which sometimes missed the shot. A comment regarding string translation is added for each routine to help with future features. - GSSAPI authentication missed two translations. - vacuumdb handles non-translated strings. Reported-by: Kyotaro Horiguchi Author: Kyotaro Horiguchi Reviewed-by: Michael Paquier, Tom Lane Discussion: https://postgr.es/m/20180810.152131.31921918.horiguchi.kyotaro@lab.ntt.co.jp Backpatch-through: 9.3
* Set scan direction appropriately for SubPlans (bug #15336)Andrew Gierth2018-08-17
| | | | | | | | | | | | | | | | | | | | When executing a SubPlan in an expression, the EState's direction field was left alone, resulting in an attempt to execute the subplan backwards if it was encountered during a backwards scan of a cursor. Also, though much less likely, it was possible to reach the execution of an InitPlan while in backwards-scan state. Repair by saving/restoring estate->es_direction and forcing forward scan mode in the relevant places. Backpatch all the way, since this has been broken since 8.3 (prior to commit c7ff7663e, SubPlans had their own EStates rather than sharing the parent plan's, so there was no confusion over scan direction). Per bug #15336 reported by Vladimir Baranoff; analysis and patch by me, review by Tom Lane. Discussion: https://postgr.es/m/153449812167.1304.1741624125628126322@wrigleys.postgresql.org
* Close the file descriptor in ApplyLogicalMappingFileTomas Vondra2018-08-16
| | | | | | | | | | | | | | The function was forgetting to close the file descriptor, resulting in failures like this: ERROR: 53000: exceeded maxAllocatedDescs (492) while trying to open file "pg_logical/mappings/map-4000-4eb-1_60DE1E08-5376b5-537c6b" LOCATION: OpenTransientFile, fd.c:2161 Simply close the file at the end, and backpatch to 9.4 (where logical decoding was introduced). While at it, fix a nearby typo. Discussion: https://www.postgresql.org/message-id/flat/738a590a-2ce5-9394-2bef-7b1caad89b37%402ndquadrant.com
* Clean up assorted misuses of snprintf()'s result value.Tom Lane2018-08-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a small number of places that were testing the result of snprintf() but doing so incorrectly. The right test for buffer overrun, per C99, is "result >= bufsize" not "result > bufsize". Some places were also checking for failure with "result == -1", but the standard only says that a negative value is delivered on failure. (Note that this only makes these places correct if snprintf() delivers C99-compliant results. But at least now these places are consistent with all the other places where we assume that.) Also, make psql_start_test() and isolation_start_test() check for buffer overrun while constructing their shell commands. There seems like a higher risk of overrun, with more severe consequences, here than there is for the individual file paths that are made elsewhere in the same functions, so this seemed like a worthwhile change. Also fix guc.c's do_serialize() to initialize errno = 0 before calling vsnprintf. In principle, this should be unnecessary because vsnprintf should have set errno if it returns a failure indication ... but the other two places this coding pattern is cribbed from don't assume that, so let's be consistent. These errors are all very old, so back-patch as appropriate. I think that only the shell command overrun cases are even theoretically reachable in practice, but there's not much point in erroneous error checks. Discussion: https://postgr.es/m/17245.1534289329@sss.pgh.pa.us
* Don't run atexit callbacks in quickdie signal handlers.Heikki Linnakangas2018-08-08
| | | | | | | | | | | | | | | | | exit() is not async-signal safe. Even if the libc implementation is, 3rd party libraries might have installed unsafe atexit() callbacks. After receiving SIGQUIT, we really just want to exit as quickly as possible, so we don't really want to run the atexit() callbacks anyway. The original report by Jimmy Yih was a self-deadlock in startup_die(). However, this patch doesn't address that scenario; the signal handling while waiting for the startup packet is more complicated. But at least this alleviates similar problems in the SIGQUIT handlers, like that reported by Asim R P later in the same thread. Backpatch to 9.3 (all supported versions). Discussion: https://www.postgresql.org/message-id/CAOMx_OAuRUHiAuCg2YgicZLzPVv5d9_H4KrL_OFsFP%3DVPekigA%40mail.gmail.com
* Don't record FDW user mappings as members of extensions.Tom Lane2018-08-07
| | | | | | | | | | | | | | | | | CreateUserMapping has a recordDependencyOnCurrentExtension call that's been there since extensions were introduced (very possibly my fault). However, there's no support anywhere else for user mappings as members of extensions, nor are they listed as a possible member object type in the documentation. Nor does it really seem like a good idea for user mappings to belong to extensions when roles don't. Hence, remove the bogus call. (As we saw in bug #15310, the lack of any pg_dump support for this case ensures that any such membership record would silently disappear during pg_upgrade. So there's probably no need for us to do anything else about cleaning up after this mistake.) Discussion: https://postgr.es/m/27952.1533667213@sss.pgh.pa.us
* Fix incorrect initialization of BackendActivityBuffer.Tom Lane2018-08-07
| | | | | | | | | | | | | Since commit c8e8b5a6e, this has been zeroed out using the wrong length. In practice the length would always be too small, leading to not zeroing the whole buffer rather than clobbering additional memory; and that's pretty harmless, both because shmem would likely start out as zeroes and because we'd reinitialize any given entry before use. Still, it's bogus, so fix it. Reported by Petru-Florin Mihancea (bug #15312) Discussion: https://postgr.es/m/153363913073.1303.6518849192351268091@wrigleys.postgresql.org
* Translation updatesPeter Eisentraut2018-08-06
| | | | | Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash: 901dbb2f9c08846927a0f103adf87e234bc47844
* Fix INSERT ON CONFLICT UPDATE through a view that isn't just SELECT *.Tom Lane2018-08-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When expanding an updatable view that is an INSERT's target, the rewriter failed to rewrite Vars in the ON CONFLICT UPDATE clause. This accidentally worked if the view was just "SELECT * FROM ...", as the transformation would be a no-op in that case. With more complicated view targetlists, this omission would often lead to "attribute ... has the wrong type" errors or even crashes, as reported by Mario De Frutos Dieguez. Fix by adding code to rewriteTargetView to fix up the data structure correctly. The easiest way to update the exclRelTlist list is to rebuild it from scratch looking at the new target relation, so factor the code for that out of transformOnConflictClause to make it sharable. In passing, avoid duplicate permissions checks against the EXCLUDED pseudo-relation, and prevent useless view expansion of that relation's dummy RTE. The latter is only known to happen (after this patch) in cases where the query would fail later due to not having any INSTEAD OF triggers for the view. But by exactly that token, it would create an unintended and very poorly tested state of the query data structure, so it seems like a good idea to prevent it from happening at all. This has been broken since ON CONFLICT was introduced, so back-patch to 9.5. Dean Rasheed, based on an earlier patch by Amit Langote; comment-kibitzing and back-patching by me Discussion: https://postgr.es/m/CAFYwGJ0xfzy8jaK80hVN2eUWr6huce0RU8AgU04MGD00igqkTg@mail.gmail.com
* Reset properly errno before calling write()Michael Paquier2018-08-05
| | | | | | | | | | | | 6cb3372 enforces errno to ENOSPC when less bytes than what is expected have been written when it is unset, though it forgot to properly reset errno before doing a system call to write(), causing errno to potentially come from a previous system call. Reported-by: Tom Lane Author: Michael Paquier Reviewed-by: Tom Lane Discussion: https://postgr.es/m/31797.1533326676@sss.pgh.pa.us
* Add table relcache invalidation to index builds.Peter Geoghegan2018-08-03
| | | | | | | | | | | | | | | | | | | | | | | | It's necessary to make sure that owning tables have a relcache invalidation prior to advancing the command counter to make newly-entered catalog tuples for the index visible. inval.c must be able to maintain the consistency of the local caches in the event of transaction abort. There is usually only a problem when CREATE INDEX transactions abort, since there is a generic invalidation once we reach index_update_stats(). This bug is of long standing. Problems were made much more likely by the addition of parallel CREATE INDEX (commit 9da0cc35284), but it is strongly suspected that similar problems can be triggered without involving plan_create_index_workers(). (plan_create_index_workers() triggers a relcache build or rebuild, which previously only happened in rare edge cases.) Author: Peter Geoghegan Reported-By: Luca Ferrari Diagnosed-By: Andres Freund Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAKoxK+5fVodiCtMsXKV_1YAKXbzwSfp7DgDqUmcUAzeAhf=HEQ@mail.gmail.com Backpatch: 9.3-
* Further fixes for quoted-list GUC values in pg_dump and ruleutils.c.Tom Lane2018-07-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 742869946 et al turn out to be a couple bricks shy of a load. We were dumping the stored values of GUC_LIST_QUOTE variables as they appear in proconfig or setconfig catalog columns. However, although that quoting rule looks a lot like SQL-identifier double quotes, there are two critical differences: empty strings ("") are legal, and depending on which variable you're considering, values longer than NAMEDATALEN might be valid too. So the current technique fails altogether on empty-string list entries (as reported by Steven Winfield in bug #15248) and it also risks truncating file pathnames during dump/reload of GUC values that are lists of pathnames. To fix, split the stored value without any downcasing or truncation, and then emit each element as a SQL string literal. This is a tad annoying, because we now have three copies of the comma-separated-string splitting logic in varlena.c as well as a fourth one in dumputils.c. (Not to mention the randomly-different-from-those splitting logic in libpq...) I looked at unifying these, but it would be rather a mess unless we're willing to tweak the API definitions of SplitIdentifierString, SplitDirectoriesString, or both. That might be worth doing in future; but it seems pretty unsafe for a back-patched bug fix, so for now accept the duplication. Back-patch to all supported branches, as the previous fix was. Discussion: https://postgr.es/m/7585.1529435872@sss.pgh.pa.us
* Document security implications of qualified names.Noah Misch2018-07-28
| | | | | | | | | | | Commit 5770172cb0c9df9e6ce27c507b449557e5b45124 documented secure schema usage, and that advice suffices for using unqualified names securely. Document, in typeconv-func primarily, the additional issues that arise with qualified names. Back-patch to 9.3 (all supported versions). Reviewed by Jonathan S. Katz. Discussion: https://postgr.es/m/20180721012446.GA1840594@rfd.leadboat.com
* Fix handling of empty uncompressed posting list pages in GINAlexander Korotkov2018-07-19
| | | | | | | | | | | | | | PostgreSQL 9.4 introduces posting list compression in GIN. This feature supports online upgrade, so that after pg_upgrade uncompressed posting lists are compressed on-the-fly. Underlying code appears to always expect at least one item on uncompressed posting list page. But there could be completely empty pages, because VACUUM never deletes leftmost and rightmost pages from posting trees. This commit fixes that. Reported-by: Sivasubramanian Ramasubramanian Discussion: https://postgr.es/m/1531867212836.63354%40amazon.com Author: Sivasubramanian Ramasubramanian, Alexander Korotkov Backpatch-through: 9.4
* Fix print of Path nodes when using OPTIMIZER_DEBUGMichael Paquier2018-07-19
| | | | | | | | | | | GatherMergePath (introduced in 10) and CustomPath (introduced in 9.5) have gone missing. The order of the Path nodes was inconsistent with what is listed in nodes.h, so make the order consistent at the same time to ease future checks and additions. Author: Sawada Masahiko Reviewed-by: Michael Paquier Discussion: https://postgr.es/m/CAD21AoBQMLoc=ohH-oocuAPsELrmk8_EsRJjOyR8FQLZkbE0wA@mail.gmail.com
* Fix misc typos, mostly in comments.Heikki Linnakangas2018-07-18
| | | | | | | | A collection of typos I happened to spot while reading code, as well as grepping for common mistakes. Backpatch to all supported versions, as applicable, to avoid conflicts when backporting other commits in the future.
* Fix inadequate buffer locking in FSM and VM page re-initialization.Tom Lane2018-07-13
| | | | | | | | | | | | | | | | | | | When reading an existing FSM or VM page that was found to be corrupt by the buffer manager, the code applied PageInit() to reinitialize the page, but did so without any locking. There is thus a hazard that two backends might concurrently do PageInit, which in itself would still be OK, but the slower one might then zero over subsequent data changes applied by the faster one. Even that is unlikely to be fatal; but it's not desirable, so add locking to prevent it. This does not add any locking overhead in the normal code path where the page is OK. It's not immediately obvious that that's safe, but I believe it is, for reasons explained in the added comments. Problem noted by R P Asim. It's been like this for a long time, so back-patch to all supported branches. Discussion: https://postgr.es/m/CANXE4Te4G0TGq6cr0-TvwP0H4BNiK_-hB5gHe8mF+nz0mcYfMQ@mail.gmail.com
* Make logical WAL sender report streaming state appropriatelyMichael Paquier2018-07-12
| | | | | | | | | | | | | | | | | | | | WAL senders sending logically-decoded data fail to properly report in "streaming" state when starting up, hence as long as one extra record is not replayed, such WAL senders would remain in a "catchup" state, which is inconsistent with the physical cousin. This can be easily reproduced by for example using pg_recvlogical and restarting the upstream server. The TAP tests have been slightly modified to detect the failure and strengthened so as future tests also make sure that a node is in streaming state when waiting for its catchup. Backpatch down to 9.4 where this code has been introduced. Reported-by: Sawada Masahiko Author: Simon Riggs, Sawada Masahiko Reviewed-by: Petr Jelinek, Michael Paquier, Vaishnavi Prabakaran Discussion: https://postgr.es/m/CAD21AoB2ZbCCqOx=bgKMcLrAvs1V0ZMqzs7wBTuDySezTGtMZA@mail.gmail.com
* Avoid emitting a bogus WAL record when recycling an all-zero btree page.Tom Lane2018-07-09
| | | | | | | | | | | | | | | | | | | | Commit fafa374f2 caused _bt_getbuf() to possibly emit a WAL record for a page that it was about to recycle. However, it failed to distinguish all-zero pages from dead pages, which is important because only the latter have valid btpo.xact values, or indeed any special space at all. Recycling an all-zero page with XLogStandbyInfoActive() enabled therefore led to an Assert failure, or to emission of a WAL record containing a bogus cutoff XID, which might lead to unnecessary query cancellations on hot standby servers. Per reports from Antonin Houska and 自己. Amit Kapila was first to propose this fix, and Robert Haas, myself, and Kyotaro Horiguchi reviewed it at various times. This is an old bug, so back-patch to all supported branches. Discussion: https://postgr.es/m/2628.1474272158@localhost Discussion: https://postgr.es/m/48875502.f4a0.1635f0c27b0.Coremail.zoulx1982@163.com
* Prevent accidental linking of system-supplied copies of libpq.so etc.Tom Lane2018-07-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | Back-patch commit dddfc4cb2, which broke LDFLAGS and related Makefile variables into two parts, one for within-build-tree library references and one for external libraries, to ensure that the order of -L flags has all of the former before all of the latter. This turns out to fix a problem recently noted on buildfarm member peripatus, that we attempted to incorporate code from libpgport.a into a shared library. That will fail on platforms that are sticky about putting non-PIC code into shared libraries. (It's quite surprising we hadn't seen such failures before, since the code in question has been like that for a long time.) I think that peripatus' problem could have been fixed with just a subset of this patch; but since the previous issue of accidentally linking to the wrong copy of a Postgres shlib seems likely to bite people in the field, let's just back-patch the whole change. Now that commit dddfc4cb2 has survived some beta testing, I'm less afraid to back-patch it than I was at the time. This also fixes undesired inclusion of "-DFRONTEND" in pg_config's CPPFLAGS output (in 9.6 and up) and undesired inclusion of "-L../../src/common" in its LDFLAGS output (in all supported branches). Back-patch to v10 and older branches; this is already in v11. Discussion: https://postgr.es/m/20180704234304.bq2dxispefl65odz@ler-imac.local
* Rework order of end-of-recovery actions to delay timeline history writeMichael Paquier2018-07-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A critical failure in some of the end-of-recovery actions before the end-of-recovery record is written can cause PostgreSQL to react inconsistently with the rest of the cluster in the event of a crash before the final record is written. Two such failures are for example an error while processing a two-phase state files or when operating on recovery.conf. With this commit, the failures are still considered FATAL, but the write of the timeline history file is delayed as much as possible so as the window between the moment the file is written and the end-of-recovery record is generated gets minimized. This way, in the event of a crash or a failure, the new timeline decided at promotion will not seem taken by other nodes in the cluster. It is not really possible to reduce to zero this window, hence one could still see failures if a crash happens between the history file write and the end-of-recovery record, so any future code should be careful when adding new end-of-recovery actions. The original report from Magnus Hagander mentioned a renamed recovery.conf as original end-of-recovery failure which caused a timeline to be seen as taken but the subsequent processing on the now-missing recovery.conf cause the startup process to issue stop on FATAL, which at follow-up startup made the system inconsistent because of on-disk changes which already happened. Processing of two-phase state files still needs some work as corrupted entries are simply ignored now. This is left as a future item and this commit fixes the original complain. Reported-by: Magnus Hagander Author: Heikki Linnakangas Reviewed-by: Alexander Korotkov, Michael Paquier, David Steele Discussion: https://postgr.es/m/CABUevEz09XY2EevA2dLjPCY-C5UO4Hq=XxmXLmF6ipNFecbShQ@mail.gmail.com
* logical decoding: beware of an unset specinsert changeAlvaro Herrera2018-07-05
| | | | | | Coverity complains that there is no protection in the code (at least in non-assertion-enabled builds) against speculative insertion failing to follow the expected protocol. Add an elog(ERROR) for the case.
* Prevent references to invalid relation pages after fresh promotionMichael Paquier2018-07-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a standby crashes after promotion before having completed its first post-recovery checkpoint, then the minimal recovery point which marks the LSN position where the cluster is able to reach consistency may be set to a position older than the first end-of-recovery checkpoint while all the WAL available should be replayed. This leads to the instance thinking that it contains inconsistent pages, causing a PANIC and a hard instance crash even if all the WAL available has not been replayed for certain sets of records replayed. When in crash recovery, minRecoveryPoint is expected to always be set to InvalidXLogRecPtr, which forces the recovery to replay all the WAL available, so this commit makes sure that the local copy of minRecoveryPoint from the control file is initialized properly and stays as it is while crash recovery is performed. Once switching to archive recovery or if crash recovery finishes, then the local copy minRecoveryPoint can be safely updated. Pavan Deolasee has reported and diagnosed the failure in the first place, and the base fix idea to rely on the local copy of minRecoveryPoint comes from Kyotaro Horiguchi, which has been expanded into a full-fledged patch by me. The test included in this commit has been written by Álvaro Herrera and Pavan Deolasee, which I have modified to make it faster and more reliable with sleep phases. Backpatch down to all supported versions where the bug appears, aka 9.3 which is where the end-of-recovery checkpoint is not run by the startup process anymore. The test gets easily supported down to 10, still it has been tested on all branches. Reported-by: Pavan Deolasee Diagnosed-by: Pavan Deolasee Reviewed-by: Pavan Deolasee, Kyotaro Horiguchi Author: Michael Paquier, Kyotaro Horiguchi, Pavan Deolasee, Álvaro Herrera Discussion: https://postgr.es/m/CABOikdPOewjNL=05K5CbNMxnNtXnQjhTx2F--4p4ruorCjukbA@mail.gmail.com
* Check for interrupts inside the nbtree page deletion code.Andres Freund2018-07-04
| | | | | | | | | | | | | | | | | | | | When deleting pages the nbtree code has to walk through siblings of a tree node. When those sibling links are corrupted that can lead to endless loops - which are currently not interruptible. This is especially problematic if autovacuum is repeatedly blocked on such indexes, as it can be hard to get out of that situation without resorting to single user mode. Thus add interrupt checks to appropriate places in such loops. Unfortunately in one of the cases it's it's not easy to do so. Between 9.3 and 9.4 the page deletion (and page split) code changed significantly. Before it was significantly less robust against interruptions. Therefore don't backpatch to 9.3. Author: Andres Freund Discussion: https://postgr.es/m/20180627191629.wkunw2qbibnvlz53@alap3.anarazel.de Backpatch: 9.4-
* Improve the performance of relation deletes during recovery.Fujii Masao2018-07-05
| | | | | | | | | | | | | | | | | | | | | | When multiple relations are deleted at the same transaction, the files of those relations are deleted by one call to smgrdounlinkall(), which leads to scan whole shared_buffers only one time. OTOH, previously, during recovery, smgrdounlink() (not smgrdounlinkall()) was called for each file to delete, which led to scan shared_buffers multiple times. Obviously this could cause to increase the WAL replay time very much especially when shared_buffers was huge. To alleviate this situation, this commit changes the recovery so that it also calls smgrdounlinkall() only one time to delete multiple relation files. This is just fix for oversight of commit 279628a0a7, not new feature. So, per discussion on pgsql-hackers, we concluded to backpatch this to all supported versions. Author: Fujii Masao Reviewed-by: Michael Paquier, Andres Freund, Thomas Munro, Kyotaro Horiguchi, Takayuki Tsunakawa Discussion: https://postgr.es/m/CAHGQGwHVQkdfDqtvGVkty+19cQakAydXn1etGND3X0PHbZ3+6w@mail.gmail.com
* Fix "base" snapshot handling in logical decodingAlvaro Herrera2018-06-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Two closely related bugs are fixed. First, xmin of logical slots was advanced too early. During xl_running_xacts processing, xmin of the slot was set to the oldest running xid in the record, but that's wrong: actually, snapshots which will be used for not-yet-replayed transactions might consider older txns as running too, so we need to keep xmin back for them. The problem wasn't noticed earlier because DDL which allows to delete tuple (set xmax) while some another not-yet-committed transaction looks at it is pretty rare, if not unique: e.g. all forms of ALTER TABLE which change schema acquire ACCESS EXCLUSIVE lock conflicting with any inserts. The included test case (test_decoding's oldest_xmin) uses ALTER of a composite type, which doesn't have such interlocking. To deal with this, we must be able to quickly retrieve oldest xmin (oldest running xid among all assigned snapshots) from ReorderBuffer. To fix, add another list of ReorderBufferTXNs to the reorderbuffer, where transactions are sorted by base-snapshot-LSN. This is slightly different from the existing (sorted by first-LSN) list, because a transaction can have an earlier LSN but a later Xmin, if its first record does not obtain an xmin (eg. xl_xact_assignment). Note this new list doesn't fully replace the existing txn list: we still need that one to prevent WAL recycling. The second issue concerns SnapBuilder snapshots and subtransactions. SnapBuildDistributeNewCatalogSnapshot never assigned a snapshot to a transaction that is known to be a subtxn, which is good in the common case that the top-level transaction already has one (no point in doing so), but a bug otherwise. To fix, arrange to transfer the snapshot from the subtxn to its top-level txn as soon as the kinship gets known. test_decoding's snapshot_transfer verifies this. Also, fix a minor memory leak: refcount of toplevel's old base snapshot was not decremented when the snapshot is transferred from child. Liberally sprinkle code comments, and rewrite a few existing ones. This part is my (Álvaro's) contribution to this commit, as I had to write all those comments in order to understand the existing code and Arseny's patch. Reported-by: Arseny Sher <a.sher@postgrespro.ru> Diagnosed-by: Arseny Sher <a.sher@postgrespro.ru> Co-authored-by: Arseny Sher <a.sher@postgrespro.ru> Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Antonin Houska <ah@cybertec.at> Discussion: https://postgr.es/m/87lgdyz1wj.fsf@ars-thinkpad
* Move RecoveryLockList into a hash table.Thomas Munro2018-06-26
| | | | | | | | | | | | | | | | | | Standbys frequently need to release all locks held by a given xid. Instead of searching one big list linearly, let's create one list per xid and put them in a hash table, so we can find what we need in O(1) time. Earlier analysis and a prototype were done by David Rowley, though this isn't his patch. Back-patch all the way. Author: Thomas Munro Diagnosed-by: David Rowley, Andres Freund Reviewed-by: Andres Freund, Tom Lane, Robert Haas Discussion: https://postgr.es/m/CAEepm%3D1mL0KiQ2KJ4yuPpLGX94a4Ns_W6TL4EGRouxWibu56pA%40mail.gmail.com Discussion: https://postgr.es/m/CAKJS1f9vJ841HY%3DwonnLVbfkTWGYWdPN72VMxnArcGCjF3SywA%40mail.gmail.com
* Address set of issues with errno handlingMichael Paquier2018-06-25
| | | | | | | | | | | | | | | | | | | | System calls mixed up in error code paths are causing two issues which several code paths have not correctly handled: 1) For write() calls, sometimes the system may return less bytes than what has been written without errno being set. Some paths were careful enough to consider that case, and assumed that errno should be set to ENOSPC, other calls missed that. 2) errno generated by a system call is overwritten by other system calls which may succeed once an error code path is taken, causing what is reported to the user to be incorrect. This patch uses the brute-force approach of correcting all those code paths. Some refactoring could happen in the future, but this is let as future work, which is not targeted for back-branches anyway. Author: Michael Paquier Reviewed-by: Ashutosh Sharma Discussion: https://postgr.es/m/20180622061535.GD5215@paquier.xyz
* Prevent hard failures of standbys caused by recycled WAL segmentsMichael Paquier2018-06-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a standby's WAL receiver stops reading WAL from a WAL stream, it writes data to the current WAL segment without having priorily zero'ed the page currently written to, which can cause the WAL reader to read junk data from a past recycled segment and then it would try to get a record from it. While sanity checks in place provide most of the protection needed, in some rare circumstances, with chances increasing when a record header crosses a page boundary, then the startup process could fail violently on an allocation failure, as follows: FATAL: invalid memory alloc request size XXX This is confusing for the user and also unhelpful as this requires in the worst case a manual restart of the instance, impacting potentially the availability of the cluster, and this also makes WAL data look like it is in a corrupted state. The chances of seeing failures are higher if the connection between the standby and its root node is unstable, causing WAL pages to be written in the middle. A couple of approaches have been discussed, like zero-ing new WAL pages within the WAL receiver itself but this has the disadvantage of impacting performance of any existing instances as this breaks the sequential writes done by the WAL receiver. This commit deals with the problem with a more simple approach, which has no performance impact without reducing the detection of the problem: if a record is found with a length higher than 1GB for backends, then do not try any allocation and report a soft failure which will force the standby to retry reading WAL. It could be possible that the allocation call passes and that an unnecessary amount of memory is allocated, however follow-up checks on records would just fail, making this allocation short-lived anyway. This patch owes a great deal to Tsunakawa Takayuki for reporting the failure first, and then discussing a couple of potential approaches to the problem. Backpatch down to 9.5, which is where palloc_extended has been introduced. Reported-by: Tsunakawa Takayuki Reviewed-by: Tsunakawa Takayuki Author: Michael Paquier Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8B57AD@G01JPEXMBYT05
* Fail BRIN control functions during recovery explicitlyAlvaro Herrera2018-06-14
| | | | | | | | | | | They already fail anyway, but prior to this patch they raise an ugly error message about a lock that cannot be acquired. This just improves the message. Author: Masahiko Sawada Reported-by: Masahiko Sawada Discussion: https://postgr.es/m/CAD21AoBZau4g4_NUf3BKNd=CdYK+xaPdtJCzvOC1TxGdTiJx_Q@mail.gmail.com Reviewed-by: Kuntal Ghosh, Alexander Korotkov, Simon Riggs, Michaël Paquier, Álvaro Herrera
* Fix bugs in vacuum of shared rels, by keeping their relcache entries current.Andres Freund2018-06-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When vacuum processes a relation it uses the corresponding relcache entry's relfrozenxid / relminmxid as a cutoff for when to remove tuples etc. Unfortunately for nailed relations (i.e. critical system catalogs) bugs could frequently lead to the corresponding relcache entry being stale. This set of bugs could cause actual data corruption as vacuum would potentially not remove the correct row versions, potentially reviving them at a later point. After 699bf7d05c some corruptions in this vein were prevented, but the additional error checks could also trigger spuriously. Examples of such errors are: ERROR: found xmin ... from before relfrozenxid ... and ERROR: found multixact ... from before relminmxid ... To be caused by this bug the errors have to occur on system catalog tables. The two bugs are: 1) Invalidations for nailed relations were ignored, based on the theory that the relcache entry for such tables doesn't change. Which is largely true, except for fields like relfrozenxid etc. This means that changes to relations vacuumed in other sessions weren't picked up by already existing sessions. Luckily autovacuum doesn't have particularly longrunning sessions. 2) For shared *and* nailed relations, the shared relcache init file was never invalidated while running. That means that for such tables (e.g. pg_authid, pg_database) it's not just already existing sessions that are affected, but even new connections are as well. That explains why the reports usually were about pg_authid et. al. To fix 1), revalidate the rd_rel portion of a relcache entry when invalid. This implies a bit of extra complexity to deal with bootstrapping, but it's not too bad. The fix for 2) is simpler, simply always remove both the shared and local init files. Author: Andres Freund Reviewed-By: Alvaro Herrera Discussion: https://postgr.es/m/20180525203736.crkbg36muzxrjj5e@alap3.anarazel.de https://postgr.es/m/CAMa1XUhKSJd98JW4o9StWPrfS=11bPgG+_GDMxe25TvUY4Sugg@mail.gmail.com https://postgr.es/m/CAKMFJucqbuoDRfxPDX39WhA3vJyxweRg_zDVXzncr6+5wOguWA@mail.gmail.com https://postgr.es/m/CAGewt-ujGpMLQ09gXcUFMZaZsGJC98VXHEFbF-tpPB0fB13K+A@mail.gmail.com Backpatch: 9.3-
* Fix function code in error reportAlvaro Herrera2018-06-06
| | | | | | | | | | | | | This bug causes a lseek() failure to be reported as a "could not open" failure in the error message, muddling bug reports. I introduced this copy-and-pasteo in commit 78e122010422. Noticed while reviewing code for bug report #15221, from lily liang. In version 10 the affected function is only used by multixact.c and commit_ts, and only in corner-case circumstances, neither of which are involved in the reported bug (a pg_subtrans failure.) Author: Álvaro Herrera
* Properly schema-qualify additional object types in getObjectDescription().Tom Lane2018-05-24
| | | | | | | | | | | | | | | | | Collations, conversions, extended statistics objects (in >= v10), and all four types of text search objects have schema-qualified names. getObjectDescription() ignored that and would emit just the base name of the object, potentially producing wrong or at least highly misleading output. Fix it to add the schema name whenever the object is not "visible" in the current search path, as is the rule for other schema-qualifiable object types. Although in common situations the output won't change, this seems to me (tgl) to be a bug worthy of back-patching, hence do so. Kyotaro Horiguchi, per a complaint from me Discussion: https://postgr.es/m/20180522.182020.114074746.horiguchi.kyotaro@lab.ntt.co.jp
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