23c57d1fa2
Replace can_modify_mm_madv() with a single vma variant, and associated checks in madvise. While we're at it, also invert the order of checks in: if (unlikely(is_ro_anon(vma) && !can_modify_vma(vma)) Checking if we can modify the vma itself (through vm_flags) is certainly cheaper than is_ro_anon() due to arch_vma_access_permitted() looking at e.g pkeys registers (with extra branches) in some architectures. This patch allows for partial madvise success when finding a sealed VMA, which historically has been allowed in Linux. Link: https://lkml.kernel.org/r/20240817-mseal-depessimize-v3-5-d8d2e037df30@gmail.com Signed-off-by: Pedro Falcato <pedro.falcato@gmail.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Kees Cook <kees@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Shuah Khan <shuah@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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.