Linux kernel source tree
0f3b1c40c6
The vmcoredd_update_size() call and its effects (size/offset changes) are currently completely unsynchronized, and will cause trouble when performed concurrently, or when done while someone is already reading the vmcore. Let's protect all vmcore modifications by the vmcore_mutex, disallow vmcore modifications while the vmcore is open, and warn on vmcore modifications after the vmcore was already opened once: modifications while the vmcore is open are unsafe, and modifications after the vmcore was opened indicates trouble. Properly synchronize against concurrent opening of the vmcore. No need to grab the mutex during mmap()/read(): after we opened the vmcore, modifications are impossible. It's worth noting that modifications after the vmcore was opened are completely unexpected, so failing if open, and warning if already opened (+closed again) is good enough. This change not only handles concurrent adding of device dumps + concurrent reading of the vmcore properly, it also prepares for other mechanisms that will modify the vmcore. Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20241204125444.1734652-4-david@redhat.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> |
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| 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 | ||
| .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.