Postgres promotion and corruption fixes, QEMU raspi and ARM work

PostgreSQL hackers addressed a promotion hang and a tuple corruption bug while iterating on logical replication conflict logging. QEMU saw substantial patch series for Raspberry Pi 4 networking, ARM64 MSHV, property schema work, RISC-V SIMD, and Arm confidential guests.

Postgres 19 promotion hang on stuck client writes

A change in commit 67c20979 left Postgres 19 promotions hanging when backends were blocked on client writes behind a ProcSignalBarrier. Hackers on pgsql-hackers discussed the failure mode and a proposed patch to unblock promotion. Operators running standby promotion paths should watch the fix before relying on the new barrier behavior.

Missing tts_tid corrupts ctid after GiST KNN

A patch fixes ExecForceStoreHeapTuple omitting tts_tid, which produced ctid corruption, unexpected table extension, and invalid pages on FOR UPDATE after GiST KNN scans. Discussion on pgsql-hackers treated the issue as a correctness and integrity defect. Anyone using GiST ordered scans with row locking needs the repair to avoid silent page damage.

QEMU raspi4b gains working PCIe and GENET

Version 4 of a patch series adds a functional PCIe root complex and GENET Ethernet to the QEMU raspi4b machine, including MDIO and DMA implementation, migration state, tests, and documentation. Two developers drove the review on qemu-devel. The work moves the model from partial hardware stubs toward usable networked guest testing.

ARM64 support for QEMU MSHV accelerator

A sixth revision of a 14-patch series adds ARM64 guest support to the QEMU MSHV accelerator by refactoring the x86 path and introducing an ARM backend for vCPU, MMIO, and vGIC. Three participants iterated on qemu-devel. The series expands MSHV beyond x86 for developers targeting Microsoft Hypervisor guests on Arm.

QOM and qdev properties linked to QAPI schema

A large seventh series (65 patches) ties QOM and qdev properties to QAPI schema types, adds qapi-type introspection, and deprecates older string-based property handling. Seven people exchanged 83 messages on qemu-devel. The change aims to make device configuration more type-safe and introspectable for tooling and long-term maintenance.

Conflict log history table for logical replication

PostgreSQL hackers continued active review of a proposal to add a conflict log history table for logical replication, with 139 messages from 14 participants. Patches are being iterated to record and expose replication conflicts more durably. The feature would give operators a clearer audit trail when apply conflicts arise in multi-node setups.

QEMU RISC-V P extension emulation

A third patchset adds full emulation for the RISC-V P (packed SIMD) extension to QEMU along with tests. The series landed as a solo submission on qemu-devel. It lets developers exercise packed-SIMD workloads in the emulator before wider hardware availability.

Arm RME realm support in QEMU

RFC version 4 (24 patches) adds Arm Realm Management Extension confidential guest support to QEMU, integrating with KVM guest-memfd and the RMM. Six participants discussed the design on qemu-devel. The work targets confidential computing use cases that need realm isolation under QEMU and KVM.