f7ddb61256
The current implementation of the compaction loop fails to set the source zspage pointer to NULL in all cases, leading to a potential issue where __zs_compact() could use a stale zspage pointer. This pointer could even point to a previously freed zspage, causing unexpected behavior in the putback_zspage() and migrate_write_unlock() functions after returning from the compaction loop. Address the issue by ensuring that the source zspage pointer is always set to NULL when it should be. Link: https://lkml.kernel.org/r/20230417130850.1784777-1-senozhatsky@chromium.org Fixes: 5a845e9f2d66 ("zsmalloc: rework compaction algorithm") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Yu Zhao <yuzhao@google.com> Tested-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Yosry Ahmed <yosryahmed@google.com> 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 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.