QEMU Rust builds, HMP optional, PG replication fixes

QEMU development led the day with Rust build integration, optional HMP, vhost-user isolation work, and ARM model additions. PostgreSQL hackers discussed a logical replication toast bug and a basebackup checksum fix during online enablement.

First Rust batch for QEMU 11.2

Paolo posted a nine-patch series that moves QEMU Rust support onto Meson 1.12 Cargo subprojects. The series removes handwritten build rules in favor of the newer Meson integration. Packagers and contributors tracking QEMU 11.2 language and build changes should follow the series.

Make HMP compile-time optional

A 49-patch series proposes a --disable-hmp configure option so the Human Monitor Protocol can be left out of QEMU builds. The stated goal is a smaller attack surface, with a path toward a later standalone HMP. Operators who ship minimal or locked-down QEMU configurations have a direct interest in the option.

vhost-user isolated memory RFC v2

An RFC v2 series of 13 patches adds an optional memory-isolation mode for vhost-user. Isolation relies on bounce buffers and shadow virtqueues so backends need not map guest memory directly. Backend authors and security-focused virtualization stacks should review the design.

Logical replication row filter and toasted columns

PostgreSQL hackers discussed a bug in which logical replication row filters turn unchanged toasted columns into NULL on the subscriber. The thread covers the failure mode and fix approaches. Sites that combine row filters with large TOAST values face silent data loss until a fix is committed.

Basebackup checksums during online enablement

A patch stops basebackup from verifying checksums on pages written before checksums were enabled. It records checksum state at the last checkpoint so concurrent online enablement no longer produces false failures. Anyone running online checksum enablement alongside base backups benefits from the correction.

Cortex-M85, SSE-310, and mps3-an555 in QEMU

A nine-patch series adds the Cortex-M85 CPU model, the SSE-310 subsystem, and the mps3-an555 board to QEMU ARM targets. The work expands coverage for recent Cortex-M class silicon and a matching board. Embedded and microcontroller emulation users gain newer models to test against.

ARM max-v8 and max-v9 CPU types

A ten-patch series splits QEMU ARM max CPU type into max-v8 and max-v9. The change accommodates Armv9 deprecation rules that a single max type handled poorly. Developers who depend on the max model for feature exploration need to adopt the new type names.

Prior vhost-user isolated memory RFC

An earlier 15-patch RFC proposed the same vhost-user isolation approach with bounce buffers and shadow virtqueues. That thread drew broad discussion across many messages and six participants. It supplies background for the security motivation later refined in the v2 series.