56ef27e3ab
Now that direct recycling is performed basing on pool->cpuid when set, memory leaks are possible: 1. A pool is destroyed. 2. Alloc cache is emptied (it's done only once). 3. pool->cpuid is still set. 4. napi_pp_put_page() does direct recycling basing on pool->cpuid. 5. Now alloc cache is not empty, but it won't ever be freed. In order to avoid that, rewrite pool->cpuid to -1 when unlinking NAPI to make sure no direct recycling will be possible after emptying the cache. This involves a bit of overhead as pool->cpuid now must be accessed via READ_ONCE() to avoid partial reads. Rename page_pool_unlink_napi() -> page_pool_disable_direct_recycling() to reflect what it actually does and unexport it. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20240215113905.96817-1-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.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 Restructured Text 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.