[PATCH v17 0/5] ring-buffer: Making persistent ring buffers robust

[Masami Hiramatsu (Google)]

Hi,

Sashiko[1] pointed out other problems. Let me review it.
I also found one mistake (not by this series), so I will fix it too.

[1] https://sashiko.dev/#/patchset/177687458572.932171.10907864814735342737.stgit%40mhiramat.tok.corp.google.com

Thanks,

On Thu, 23 Apr 2026 01:16:26 +0900
"Masami Hiramatsu (Google)" <mhiramat at kernel.org> wrote:

> Hi,
> 
> Here is the 17th version of improvement patches for making persistent
> ring buffers robust to failures.
> The previous version is here:
> 
> https://lore.kernel.org/all/177547105523.259641.14385891517704197263.stgit@mhiramat.tok.corp.google.com/
> 
> This version fixes some review comments from Sashiko[1], which
> includes:
> [2/5] Fix to use rb_page_size() of rewound pages for entry_bytes.
> [3/5] - Fix to verify head_page at first before using its timestamp.
>       - Reset timestamp if the page is invalid.
> [4/5] - In rb_test_inject_invalid_pages(), changed entry_bytes and
>        idx to unsigned long
>       - Added NULL checks for cpu_buffer and meta.
>       - In allocate_trace_buffer(), added a NULL check for tr->name
>        before comparing it with strcmp.
> [5/5] Added NULL check for dpage in rbm_show in ring_buffer.c.
> 
> [1] https://sashiko.dev/#/patchset/177552432201.853249.5125045538812833325.stgit%40mhiramat.tok.corp.google.com
> 
> Thank you,
> 
> Masami Hiramatsu (Google) (5):
>       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
> 
> 
>  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           |  275 ++++++++++++++++++++++++++--------
>  kernel/trace/trace.c                 |    4 
>  26 files changed, 290 insertions(+), 67 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>