PostgreSQL crash fix, backup checks, and QEMU isolation RFCs

PostgreSQL developers fixed a locale-related crash on the 18 stable branch and advanced patches for backup verification, logical replication, and safer formatting buffers. QEMU threads focused on vhost-user memory isolation, RISC-V confidential VMs, and shared guest-memfd backends.

Crash fix for pg_strupper on PostgreSQL 18 stable

A crash in pg_strupper() under the C locale on REL_18_STABLE followed a recent commit. Participants on pgsql-hackers diagnosed the regression and pushed a fix. Operators tracking the PostgreSQL 18 line need the correction to avoid the failure path.

Detection of truncated compressed backups

A patchset addresses pg_verifybackup failing to notice truncated zstd, gzip, and lz4 backups. Review and test discussion refined the changes across twenty messages. Reliable truncation detection matters for anyone verifying compressed base backups.

Logical replication row filters and toasted columns

Row filters in logical replication were reported to turn unchanged toasted columns into NULL on the subscriber. Hackers discussed the bug and a corresponding fix. Deployments that combine row filters with toasted data should watch the outcome.

vhost-user memory isolation RFC

An RFC series of fifteen patches proposes isolating vhost-user memory with bounce buffers and shadow virtqueues so backends need not map guest memory directly. Six participants debated the design on qemu-devel. The work targets stronger separation between guests and device backends.

RISC-V CoVE confidential VM support

An RFC series adds QEMU KVM support for RISC-V CoVE confidential VMs, following patterns used for SEV and TDX. Two authors iterated on the seventeen-patch set. The series expands confidential computing options for RISC-V guests.

Init-shared guest-memfd as hostmem backends

Version four of a twelve-patch series lets QEMU hostmem treat fully shared init-shared guest-memfd as VM backends, with renames that separate private and shared paths. Five reviewers examined the changes. The update clarifies how shared guest memory is wired into KVM VMs.

StringInfo buffers for formatting.c

Tom Lane proposed moving formatting.c to StringInfo output buffers to remove a class of past buffer-related CVEs. The proposal opens that cleanup on pgsql-hackers. Safer buffer handling reduces recurrence of earlier overflow issues.

LibreSSL versus OpenSSL handling in libpq

Hackers debated whether to split LibreSSL into separate libpq TLS source files or keep shared code, weighing maintenance cost against OpenSSL 1.1.1 deprecation. Five participants exchanged views. The decision shapes how libpq will support multiple TLS libraries.