mirror of
https://github.com/torvalds/linux.git
synced 2026-10-11 12:58:02 +02:00
Linux kernel source tree
bdf253d580
The support for asynchronous hashes in dm-verity has outlived its usefulness. It adds significant code complexity and opportunity for bugs. I don't know of anyone using it in practice. (The original submitter of the code possibly was, but that was 8 years ago.) Data I recently collected for en/decryption shows that using off-CPU crypto "accelerators" is consistently much slower than the CPU (https://lore.kernel.org/r/20250704070322.20692-1-ebiggers@kernel.org/), even on CPUs that lack dedicated cryptographic instructions. Similar results are likely to be seen for hashing. I already removed support for asynchronous hashes from fsverity two years ago, and no one ever complained. Moreover, neither dm-verity, fsverity, nor fscrypt has ever actually used the asynchronous crypto algorithms in a truly asynchronous manner. The lack of interest in such optimizations provides further evidence that it's only the CPU-based crypto that actually matters. Historically, it's also been common for people to forget to enable the optimized SHA-256 code, which could contribute to an off-CPU crypto engine being perceived as more useful than it really is. In 6.16 I fixed that: the optimized SHA-256 code is now enabled by default. Therefore, let's drop the support for asynchronous hashes in dm-verity. Tested with verity-compat-test. Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> |
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .pylintrc | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.