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Jakub Kicinski 918fb1aaa2 Merge branch 'stop-corrupting-socket-s-task_frag'
Benjamin Coddington says:

====================
Stop corrupting socket's task_frag

The networking code uses flags in sk_allocation to determine if it can use
current->task_frag, however in-kernel users of sockets may stop setting
sk_allocation when they convert to the preferred memalloc_nofs_save/restore,
as SUNRPC has done in commit a1231fda7e ("SUNRPC: Set memalloc_nofs_save()
on all rpciod/xprtiod jobs").

This will cause corruption in current->task_frag when recursing into the
network layer for those subsystems during page fault or reclaim.  The
corruption is difficult to diagnose because stack traces may not contain the
offending subsystem at all.  The corruption is unlikely to show up in
testing because it requires memory pressure, and so subsystems that
convert to memalloc_nofs_save/restore are likely to continue to run into
this issue.

Previous reports and proposed fixes:
https://lore.kernel.org/netdev/96a18bd00cbc6cb554603cc0d6ef1c551965b078.1663762494.git.gnault@redhat.com/
https://lore.kernel.org/netdev/b4d8cb09c913d3e34f853736f3f5628abfd7f4b6.1656699567.git.gnault@redhat.com/
https://lore.kernel.org/linux-nfs/de6d99321d1dcaa2ad456b92b3680aa77c07a747.1665401788.git.gnault@redhat.com/

Guilluame Nault has done all of the hard work tracking this problem down and
finding the best fix for this issue.  I'm just taking a turn posting another
fix.
====================

Link: https://lore.kernel.org/r/cover.1671194454.git.bcodding@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-19 17:28:52 -08:00
arch Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
block for-6.2/block-2022-12-08 2022-12-13 10:43:59 -08:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto iov_iter work; most of that is about getting rid of 2022-12-12 18:29:54 -08:00
Documentation docs/bpf: Reword docs for BPF_MAP_TYPE_SK_STORAGE 2022-12-14 18:35:41 +01:00
drivers Treewide: Stop corrupting socket's task_frag 2022-12-19 17:28:49 -08:00
fs Treewide: Stop corrupting socket's task_frag 2022-12-19 17:28:49 -08:00
include net: simplify sk_page_frag 2022-12-19 17:28:50 -08:00
init modules changes for v6.2-rc1 2022-12-13 14:05:39 -08:00
io_uring for-6.2/block-2022-12-08 2022-12-13 10:43:59 -08:00
ipc Non-MM patches for 6.2-rc1. 2022-12-12 17:28:58 -08:00
kernel bpf: Resolve fext program type when checking map compatibility 2022-12-14 21:30:27 -08:00
lib Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm for-6.2/block-2022-12-08 2022-12-13 10:43:59 -08:00
net Treewide: Stop corrupting socket's task_frag 2022-12-19 17:28:49 -08:00
rust rust: types: add Opaque type 2022-12-04 01:59:16 +01:00
samples Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
scripts Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
security integrity-v6.2 2022-12-13 14:22:50 -08:00
sound sound updates for 6.2-rc1 2022-12-13 11:27:26 -08:00
tools bpf-for-netdev 2022-12-16 10:41:56 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt Merge branch 'kvm-dwmw2-fixes' into HEAD 2022-11-23 18:59:45 -05:00
.clang-format printk changes for 6.2 2022-12-12 09:01:36 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: Cleanup DT Overlay intermediate files as appropriate 2022-11-18 14:45:30 -06:00
.mailmap Non-MM patches for 6.2-rc1. 2022-12-12 17:28:58 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
Makefile This was a not-too-busy cycle for documentation; highlights include: 2022-12-12 17:18:50 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.