client return "PD returned no region" without additional information

[lcwangchao]

When execute SHOW PLACEMENT it returns an error with some log:

 [sql=\"show table geopartition.tx regions\"] [txn_mode=PESSIMISTIC] [timestamp=0] [err=\"PD returned no region\\ngithub.com/tikv/client-go/v2/internal/locate.(*RegionCache).scanRegions\\n\\t/go/pkg/mod/github.com/tikv/client-go/v2@v2.0.8-0.20230621031026-864a5fc0c482/internal/locate/region_cache.go:1722\\ngithub.com/tikv/client-go/v2/internal/locate.(*RegionCache).BatchLoadRegionsWithKeyRange\\n\\t/go/pkg/mod/github.com/tikv/client-go/v2@v2.0.8-0.20230621031026-864a5fc0c482/internal/locate/region_cache.go:1298\\ngithub.com/tikv/client-go/v2/internal/locate.(*RegionCache).LoadRegionsInKeyRange\\n\\t/go/pkg/mod/github.com/tikv/client-go/v2@v2.0.8-0.20230621031026-864a5fc0c482/internal/locate/region_cache.go:1277\\ngithub.com/pingcap/tidb/executor.getPhysicalTableRegions\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/split.go:642\\ngithub.com/pingcap/tidb/executor.getTableRegions\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/show.go:2115\\ngithub.com/pingcap/tidb/executor.(*ShowExec).fetchShowTableRegions\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/show.go:2043\\ngithub.com/pingcap/tidb/executor.(*ShowExec).fetchAll\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/show.go:265\\ngithub.com/pingcap/tidb/executor.(*ShowExec).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/show.go:128\\ngithub.com/pingcap/tidb/executor.Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/executor.go:342\\ngithub.com/pingcap/tidb/executor.(*ExecStmt).next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/adapter.go:1218\\ngithub.com/pingcap/tidb/executor.(*recordSet).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/adapter.go:151\\ngithub.com/pingcap/tidb/server.(*tidbResultSet).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/driver_tidb.go:429\\ngithub.com/pingcap/tidb/server.(*clientConn).writeChunks\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2335\\ngithub.com/pingcap/tidb/server.(*clientConn).writeResultSet\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2278\\ngithub.com/pingcap/tidb/server.(*clientConn).handleStmt\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2151\\ngithub.com/pingcap/tidb/server.(*clientConn).handleQuery\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1912\\ngithub.com/pingcap/tidb/server.(*clientConn).dispatch\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1399\\ngithub.com/pingcap/tidb/server.(*clientConn).Run\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1178\\ngithub.com/pingcap/tidb/server.(*Server).onConn\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/server.go:663\\nruntime.goexit\\n\\t/usr/local/go/src/runtime/asm_amd64.s:1598\\ngithub.com/pingcap/errors.AddStack\\n\\t/go/pkg/mod/github.com/pingcap/errors@v0.11.5-0.20221009092201-b66cddb77c32/errors.go:174\\ngithub.com/pingcap/errors.Trace\\n\\t/go/pkg/mod/github.com/pingcap/errors@v0.11.5-0.20221009092201-b66cddb77c32/juju_adaptor.go:15\\ngithub.com/pingcap/tidb/executor.(*ShowExec).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/show.go:130\\ngithub.com/pingcap/tidb/executor.Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/executor.go:342\\ngithub.com/pingcap/tidb/executor.(*ExecStmt).next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/adapter.go:1218\\ngithub.com/pingcap/tidb/executor.(*recordSet).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/executor/adapter.go:151\\ngithub.com/pingcap/tidb/server.(*tidbResultSet).Next\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/driver_tidb.go:429\\ngithub.com/pingcap/tidb/server.(*clientConn).writeChunks\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2335\\ngithub.com/pingcap/tidb/server.(*clientConn).writeResultSet\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2278\\ngithub.com/pingcap/tidb/server.(*clientConn).handleStmt\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:2151\\ngithub.com/pingcap/tidb/server.(*clientConn).handleQuery\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1912\\ngithub.com/pingcap/tidb/server.(*clientConn).dispatch\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1399\\ngithub.com/pingcap/tidb/server.(*clientConn).Run\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/conn.go:1178\\ngithub.com/pingcap/tidb/server.(*Server).onConn\\n\\t/home/jenkins/agent/workspace/build-common/go/src/github.com/pingcap/tidb/server/server.go:663\\nruntime.goexit\\n\\t/usr/local/go/src/runtime/asm_amd64.s:1598\"]"}

However, it cannot be reproduced. I think we should add more information when "PD returned no region" happens to help us to find the real reason in log