No description
fd1464105c
The implementation of bdev holder operations such as fs_bdev_mark_dead() and fs_bdev_sync() grab sb->s_umount semaphore under bdev->bd_holder_lock. This is problematic because it leads to disk->open_mutex -> sb->s_umount lock ordering which is counterintuitive (usually we grab higher level (e.g. filesystem) locks first and lower level (e.g. block layer) locks later) and indeed makes lockdep complain about possible locking cycles whenever we open a block device while holding sb->s_umount semaphore. Implement a function bdev_super_lock_shared() which safely transitions from holding bdev->bd_holder_lock to holding sb->s_umount on alive superblock without introducing the problematic lock dependency. We use this function fs_bdev_sync() and fs_bdev_mark_dead(). Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20231018152924.3858-1-jack@suse.cz Link: https://lore.kernel.org/r/20231017184823.1383356-1-hch@lst.de Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org> |
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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 | ||
| .cocciconfig | ||
| .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 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.