BPF verifier redesigns and lockless page-cache reads lead the kernel lists

Kernel lists on 11 November were dominated by large BPF and memory-management series, plus filesystem and LSM work aimed at long-standing correctness and portability gaps. A camera-driver submission also drew a sharp maintainer rejection over AI-generated patches.

BPF series aims to auto-detect fmodret attach points

A v3 patch set on bpf-next adds an LLVM IR plugin and supporting changes so the kernel can discover functions that accept fmodret BPF attachments instead of relying only on static lists. The work matters because fmodret attachment is currently limited by hand-maintained allow lists, which lag new kernel functions and force developers to update those lists by hand.

Verifier series drops scalar IDs for SCEV-based register tracking

Alexei Starovoitov posted a v2 series of 29 patches that replaces scalar IDs in the BPF verifier with linked-register tracking based on scalar evolution. The change is aimed at how the verifier reasons about related registers, a core path for program acceptance and rejection.

RFC lets filemap and shmem reads skip folio references

An RFC v2, originated by Linus Torvalds and posted from Meta, introduces PG_rcu_free and an RCU grace period so lockless filemap and shmem reads can proceed without taking folio references. The goal is to avoid folio refcount contention on the page-cache read path.

Inode reclaim fix targets stuck metadata-writeback inodes

A patch series on the stable list addresses an inode reclaim bug on ext2, ext4 without a journal, fat, udf, and minix. Under memory pressure, inodes can be left in an unrecoverable I_METADATA_WRITEBACK state and contribute to out-of-memory conditions.

/proc handler series cleans up long-standing bugs

Christian Brauner posted v2 of a 51-patch series, the first of seven parts, fixing bugs in /proc readdir, sysctl locking, pktgen name handling, and vmcore. The defects turned up while moving procfs toward kernfs, so the series is both a bugfix set and groundwork for that conversion.

F2FS gains support for blocks smaller than the page

Google posted a 20-patch series that lets F2FS use a block size smaller than PAGE_SIZE on kernels with 16 KB pages. The main stated use is Android userdata migration onto those larger-page kernels.

Landlock adds metadata read and write rights

A v3 Landlock series adds READ_METADATA and WRITE_METADATA access rights, after refactoring LSM inode hooks to pass a struct path and a file. The new rights give policies a finer split between metadata access and other file operations.

Maintainers reject AI-generated SM8150 camera patches

An eight-patch series adding SM8150 CAMSS support and LG G8x ThinQ camera sensors was rejected by maintainers for duplication and inadequate review. They also warned that future submissions of that kind may be ignored.