![]() Ritesh and Eric separately reported crashes in XFS's hook function for CPU hot remove if the remove event races with a filesystem being mounted. I also noticed via generic/650 that once in a while the log will shut down over an apparent overrun of a transaction reservation; this turned out to be due to CIL percpu list aggregation failing to pick up the percpu list items from a dying CPU. Either way, the solution here is to eliminate the need for a CPU dying hook by using a private cpumask to track which CPUs have added to their percpu lists directly, and iterating with that mask. This fixes the log problems and (I think) solves a theoretical UAF bug in the inodegc code too. v2: fix a few put_cpu uses, add necessary memory barriers, and use atomic cpumask operations This has been lightly tested with fstests. Enjoy! Signed-off-by: Darrick J. Wong <djwong@kernel.org> -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQQ2qTKExjcn+O1o2YRKO3ySh0YRpgUCZQChOQAKCRBKO3ySh0YR plauAQCV0RymbwD/ONbvpor3yK4R3YO1pa923KtoiQ9IAV5uswD/YBWvyI76BhNs B8hwbEDm3X2ZjQaikxI+Xx2cMaAhkgY= =EJ0b -----END PGP SIGNATURE----- Merge tag 'fix-percpu-lists-6.6_2023-09-12' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-6.6-fixesA xfs: fix cpu hotplug mess Ritesh and Eric separately reported crashes in XFS's hook function for CPU hot remove if the remove event races with a filesystem being mounted. I also noticed via generic/650 that once in a while the log will shut down over an apparent overrun of a transaction reservation; this turned out to be due to CIL percpu list aggregation failing to pick up the percpu list items from a dying CPU. Either way, the solution here is to eliminate the need for a CPU dying hook by using a private cpumask to track which CPUs have added to their percpu lists directly, and iterating with that mask. This fixes the log problems and (I think) solves a theoretical UAF bug in the inodegc code too. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org> * tag 'fix-percpu-lists-6.6_2023-09-12' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux: xfs: remove CPU hotplug infrastructure xfs: remove the all-mounts list xfs: use per-mount cpumask to track nonempty percpu inodegc lists xfs: fix per-cpu CIL structure aggregation racing with dying cpus |
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Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
io_uring | ||
ipc | ||
kernel | ||
lib | ||
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 |
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.