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Steven Rostedt 4994e387d7 x86/mm/kmmio: Switch to arch_spin_lock()
The mmiotrace tracer is "special". The purpose is to help reverse engineer
binary drivers by removing the memory allocated by the driver and when the
driver goes to access it, a fault occurs, the mmiotracer will record what
the driver was doing and then do the work on its behalf by single stepping
through the process.

But to achieve this ability, it must do some special things. One is it
needs to grab a lock while in the breakpoint handler. This is considered
an NMI state, and then lockdep warns that the lock is being held in both
an NMI state (really a breakpoint handler) and also in normal context.

As the breakpoint/NMI state only happens when the driver is accessing
memory, there's no concern of a race condition against the setup and
tear-down of mmiotracer.

To make lockdep and mmiotrace work together, convert the locks used in the
breakpoint handler into arch_spin_lock().

Link: https://lkml.kernel.org/r/20221206191229.656244029@goodmis.org
Link: https://lore.kernel.org/lkml/20221201213126.620b7dd3@gandalf.local.home/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Karol Herbst <karolherbst@gmail.com>
Cc: Pekka Paalanen <ppaalanen@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-09 23:48:06 -05:00
arch x86/mm/kmmio: Switch to arch_spin_lock() 2022-12-09 23:48:06 -05:00
block block-6.1-2022-11-18 2022-11-18 13:59:45 -08:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto treewide: use get_random_bytes() when possible 2022-10-11 17:42:58 -06:00
Documentation tracing: docs: Update histogram doc for .percent/.graph and 'nohitcount' 2022-12-09 23:48:05 -05:00
drivers SCSI fixes on 20221119 2022-11-19 15:51:22 -08:00
fs 4 cifs/smb3 client fixes 2022-11-19 08:58:58 -08:00
include tracing: Optimize event type allocation with IDA 2022-11-23 19:08:31 -05:00
init init: Kconfig: fix spelling mistake "satify" -> "satisfy" 2022-10-20 21:27:22 -07:00
io_uring io_uring: disallow self-propelled ring polling 2022-11-18 09:29:31 -07:00
ipc ipc/msg.c: fix percpu_counter use after free 2022-10-28 13:37:22 -07:00
kernel tracing: Fix complicated dependency of CONFIG_TRACER_MAX_TRACE 2022-12-09 23:48:05 -05:00
lib maple_tree: don't set a new maximum on the node when not reusing nodes 2022-11-08 15:57:25 -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 Networking fixes for 6.1-rc6, including fixes from bpf 2022-11-17 08:58:36 -08:00
net tcp: configurable source port perturb table size 2022-11-16 13:02:04 +00:00
rust Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
samples tracing: Add __cpumask to denote a trace event field that is a cpumask_t 2022-11-23 19:08:30 -05:00
scripts kbuild: Restore .version auto-increment behaviour for Debian packages 2022-11-17 17:51:45 +09:00
security lsm/stable-6.1 PR 20221031 2022-10-31 12:09:42 -07:00
sound ALSA: hda/realtek: Fix the speaker output on Samsung Galaxy Book Pro 360 2022-11-15 18:03:31 +01:00
tools Char/Misc driver fixes for 6.1-rc6 2022-11-18 10:29:25 -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 tag 'kvmarm-fixes-6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD 2022-11-06 03:30:49 -05:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig
.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: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap sound fixes for 6.1-rc6 2022-11-18 09:52:10 -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 tracing: Update MAINTAINERS file for new patchwork and mailing list 2022-11-28 19:07:40 -05:00
Makefile Linux 6.1-rc6 2022-11-20 16:02:16 -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.