kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-26 19:14:18 +00:00
Code Issues Releases Packages Activity
No description
1,237,107 commits 117 branches 5,805 tags 5.9 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Tejun Heo cd33b330cb blk-iocost: Fix an UBSAN shift-out-of-bounds warning 
[ Upstream commit 2a427b49d0 ]

When iocg_kick_delay() is called from a CPU different than the one which set
the delay, @now may be in the past of @iocg->delay_at leading to the
following warning:

  UBSAN: shift-out-of-bounds in block/blk-iocost.c:1359:23
  shift exponent 18446744073709 is too large for 64-bit type 'u64' (aka 'unsigned long long')
  ...
  Call Trace:
   <TASK>
   dump_stack_lvl+0x79/0xc0
   __ubsan_handle_shift_out_of_bounds+0x2ab/0x300
   iocg_kick_delay+0x222/0x230
   ioc_rqos_merge+0x1d7/0x2c0
   __rq_qos_merge+0x2c/0x80
   bio_attempt_back_merge+0x83/0x190
   blk_attempt_plug_merge+0x101/0x150
   blk_mq_submit_bio+0x2b1/0x720
   submit_bio_noacct_nocheck+0x320/0x3e0
   __swap_writepage+0x2ab/0x9d0

The underflow itself doesn't really affect the behavior in any meaningful
way; however, the past timestamp may exaggerate the delay amount calculated
later in the code, which shouldn't be a material problem given the nature of
the delay mechanism.

If @now is in the past, this CPU is racing another CPU which recently set up
the delay and there's nothing this CPU can contribute w.r.t. the delay.
Let's bail early from iocg_kick_delay() in such cases.

Reported-by: Breno Leitão <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 5160a5a53c ("blk-iocost: implement delay adjustment hysteresis")
Link: https://lore.kernel.org/r/ZVvc9L_CYk5LO1fT@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-02-16 19:14:27 +01:00
arch riscv: declare overflow_stack as exported from traps.c 2024-02-16 19:14:27 +01:00
block blk-iocost: Fix an UBSAN shift-out-of-bounds warning 2024-02-16 19:14:27 +01:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: api - Disallow identical driver names 2024-01-31 16:20:54 -08:00
Documentation net: sysfs: Fix /sys/class/net/<iface> path 2024-02-05 20:17:10 +00:00
drivers nvme-host: fix the updating of the firmware version 2024-02-16 19:14:27 +01:00
fs ceph: always set initial i_blkbits to CEPH_FSCRYPT_BLOCK_SHIFT 2024-02-16 19:14:26 +01:00
include libceph: just wait for more data to be available on the socket 2024-02-16 19:14:26 +01:00
init rootfs: Fix support for rootfstype= when root= is given 2024-01-25 15:45:15 -08:00
io_uring io_uring: adjust defer tw counting 2024-01-25 15:45:30 -08:00
ipc Many singleton patches against the MM code. The patch series which are 2023-11-02 19:38:47 -10:00
kernel perf: Fix the nr_addr_filters fix 2024-02-05 20:17:06 +00:00
lib kunit: run test suites only after module initialization completes 2024-02-05 20:17:07 +00:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: Introduce flush_cache_vmap_early() 2024-02-16 19:14:25 +01:00
net libceph: just wait for more data to be available on the socket 2024-02-16 19:14:26 +01:00
rust rust: Ignore preserve-most functions 2024-01-25 15:45:09 -08:00
samples Landlock updates for v6.7-rc1 2023-11-03 09:28:53 -10:00
scripts scripts/get_abi: fix source path leak 2024-01-31 16:21:00 -08:00
security lsm: new security_file_ioctl_compat() hook 2024-01-31 16:21:00 -08:00
sound ASoC: codecs: wsa883x: fix PA volume control 2024-02-05 20:17:12 +00:00
tools selftests: core: include linux/close_range.h for CLOSE_RANGE_* macros 2024-02-16 19:14:27 +01:00
usr arch: Remove Itanium (IA-64) architecture 2023-09-11 08:13:17 +00:00
virt KVM/arm64 fixes for 6.7, part #2 2023-12-22 18:03:54 -05:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.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: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: generate kernel.spec in rpmbuild/SPECS/ 2023-10-03 20:49:09 +09:00
.mailmap 12 hotfixes. 2 are cc:stable and the remainder either address post-6.7 2024-01-05 13:46:18 -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 12 hotfixes. 2 are cc:stable and the remainder either address post-6.7 2024-01-05 13:46:18 -08:00
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 12 hotfixes. 2 are cc:stable and the remainder either address post-6.7 2024-01-05 13:46:18 -08:00
Makefile Linux 6.7.4 2024-02-05 20:17:12 +00:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.