[PATCH v18 0/8] ring-buffer: Making persistent ring buffers robust

[Masami Hiramatsu (Google)]

Hi Steve,

I added a fix related this series as the 1st one. It can be merged
independently.

Thanks,

On Fri, 24 Apr 2026 15:51:59 +0900
"Masami Hiramatsu (Google)" <mhiramat at kernel.org> wrote:

> Hi,
> 
> Here is the 18th version of improvement patches for making persistent
> ring buffers robust to failures.
> The previous version is here:
> 
> https://lore.kernel.org/all/177687458572.932171.10907864814735342737.stgit@mhiramat.tok.corp.google.com/
> 
> This version fixes a newly found bug and some review comments from
> Sashiko[1], also, add 2 cleanups, which includes:
> [1/8] Do not double count the reader_page when verifying persistent
>       ring buffer.
> [2/8] Add Geert's Ack (Thanks!)
> [3/8] Fix to substract BUF_PAGE_HDR_SIZE from meta->subbuf_size
>       to make the limit of commit size.
> [4/8] Reset timestamp of reader_page when the entire cpu_buffer is
>       invalid.
> [5/8] In rb_test_inject_invalid_pages(), changed entry_bytes and
>       idx to unsigned long.
> [7/8] Cleanup persistent ring buffer validation code.
> [8/8] Cleanup buffer_data_page related code.
> 
> [1] https://sashiko.dev/#/patchset/177687458572.932171.10907864814735342737.stgit%40mhiramat.tok.corp.google.com
> 
> Thank you,
> 
> Masami Hiramatsu (Google) (8):
>       ring-buffer: Do not double count the reader_page
>       ring-buffer: Flush and stop persistent ring buffer on panic
>       ring-buffer: Skip invalid sub-buffers when validating persistent ring buffer
>       ring-buffer: Skip invalid sub-buffers when rewinding persistent ring buffer
>       ring-buffer: Add persistent ring buffer invalid-page inject test
>       ring-buffer: Show commit numbers in buffer_meta file
>       ring-buffer: Cleanup persistent ring buffer validation
>       ring-buffer: Cleanup buffer_data_page related code
> 
> 
>  arch/alpha/include/asm/Kbuild        |    1 
>  arch/arc/include/asm/Kbuild          |    1 
>  arch/arm/include/asm/Kbuild          |    1 
>  arch/arm64/include/asm/ring_buffer.h |   10 +
>  arch/csky/include/asm/Kbuild         |    1 
>  arch/hexagon/include/asm/Kbuild      |    1 
>  arch/loongarch/include/asm/Kbuild    |    1 
>  arch/m68k/include/asm/Kbuild         |    1 
>  arch/microblaze/include/asm/Kbuild   |    1 
>  arch/mips/include/asm/Kbuild         |    1 
>  arch/nios2/include/asm/Kbuild        |    1 
>  arch/openrisc/include/asm/Kbuild     |    1 
>  arch/parisc/include/asm/Kbuild       |    1 
>  arch/powerpc/include/asm/Kbuild      |    1 
>  arch/riscv/include/asm/Kbuild        |    1 
>  arch/s390/include/asm/Kbuild         |    1 
>  arch/sh/include/asm/Kbuild           |    1 
>  arch/sparc/include/asm/Kbuild        |    1 
>  arch/um/include/asm/Kbuild           |    1 
>  arch/x86/include/asm/Kbuild          |    1 
>  arch/xtensa/include/asm/Kbuild       |    1 
>  include/asm-generic/ring_buffer.h    |   13 +
>  include/linux/ring_buffer.h          |    1 
>  kernel/trace/Kconfig                 |   34 ++
>  kernel/trace/ring_buffer.c           |  472 +++++++++++++++++++++++-----------
>  kernel/trace/trace.c                 |    4 
>  26 files changed, 395 insertions(+), 159 deletions(-)
>  create mode 100644 arch/arm64/include/asm/ring_buffer.h
>  create mode 100644 include/asm-generic/ring_buffer.h
> 
> 
> base-commit: 6170922f137231b98fc568571befef63e1edff3f
> --
> Masami Hiramatsu (Google) <mhiramat at kernel.org>


-- 
Masami Hiramatsu (Google) <mhiramat at kernel.org>