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Arnd Bergmann 3b1ddbb62e This is an attempt to harden the typing on virt_to_pfn()
and pfn_to_virt().
 
 Making virt_to_pfn() a static inline taking a strongly typed
 (const void *) makes the contract of a passing a pointer of that
 type to the function explicit and exposes any misuse of the
 macro virt_to_pfn() acting polymorphic and accepting many types
 such as (void *), (unitptr_t) or (unsigned long) as arguments
 without warnings.
 
 For symmetry, we do the same with pfn_to_virt().
 
 The problem with this inconsistent typing was pointed out by
 Russell King:
 https://lore.kernel.org/linux-arm-kernel/YoJDKJXc0MJ2QZTb@shell.armlinux.org.uk/
 
 And confirmed by Andrew Morton:
 https://lore.kernel.org/linux-mm/20220701160004.2ffff4e5ab59a55499f4c736@linux-foundation.org/
 
 So the recognition of the problem is widespread.
 
 These platforms have been chosen as initial conversion targets:
 
 - ARM
 - ARM64/Aarch64
 - asm-generic (including for example x86)
 - m68k
 
 The idea is that if this goes in, it will block further misuse
 of the function signatures due to the large compile coverage,
 and then I can go in and fix the remaining architectures on a
 one-by-one basis.
 
 Some of the patches have been circulated before but were not
 picked up by subsystem maintainers, so now the arch tree is
 target for this series.
 
 It has passed zeroday builds after a lot of iterations in my
 personal tree, but there could be some randconfig outliers.
 New added or deeply hidden problems appear all the time so
 some minor fallout can be expected.
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Merge tag 'virt-to-pfn-for-arch-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-integrator into asm-generic

This is an attempt to harden the typing on virt_to_pfn()
and pfn_to_virt().

Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

For symmetry, we do the same with pfn_to_virt().

The problem with this inconsistent typing was pointed out by
Russell King:
https://lore.kernel.org/linux-arm-kernel/YoJDKJXc0MJ2QZTb@shell.armlinux.org.uk/

And confirmed by Andrew Morton:
https://lore.kernel.org/linux-mm/20220701160004.2ffff4e5ab59a55499f4c736@linux-foundation.org/

So the recognition of the problem is widespread.

These platforms have been chosen as initial conversion targets:

- ARM
- ARM64/Aarch64
- asm-generic (including for example x86)
- m68k

The idea is that if this goes in, it will block further misuse
of the function signatures due to the large compile coverage,
and then I can go in and fix the remaining architectures on a
one-by-one basis.

Some of the patches have been circulated before but were not
picked up by subsystem maintainers, so now the arch tree is
target for this series.

It has passed zeroday builds after a lot of iterations in my
personal tree, but there could be some randconfig outliers.
New added or deeply hidden problems appear all the time so
some minor fallout can be expected.

* tag 'virt-to-pfn-for-arch-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-integrator:
  m68k/mm: Make pfn accessors static inlines
  arm64: memory: Make virt_to_pfn() a static inline
  ARM: mm: Make virt_to_pfn() a static inline
  asm-generic/page.h: Make pfn accessors static inlines
  xen/netback: Pass (void *) to virt_to_page()
  netfs: Pass a pointer to virt_to_page()
  cifs: Pass a pointer to virt_to_page() in cifsglob
  cifs: Pass a pointer to virt_to_page()
  riscv: mm: init: Pass a pointer to virt_to_page()
  ARC: init: Pass a pointer to virt_to_pfn() in init
  m68k: Pass a pointer to virt_to_pfn() virt_to_page()
  fs/proc/kcore.c: Pass a pointer to virt_addr_valid()
2023-05-31 16:33:56 +02:00
arch This is an attempt to harden the typing on virt_to_pfn() 2023-05-31 16:33:56 +02:00
block block: make bio_check_eod work for zero sized devices 2023-05-24 08:19:26 -06:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
Documentation A set of fixes for interrupt chip drivers: 2023-05-28 07:12:21 -04:00
drivers This is an attempt to harden the typing on virt_to_pfn() 2023-05-31 16:33:56 +02:00
fs This is an attempt to harden the typing on virt_to_pfn() 2023-05-31 16:33:56 +02:00
include This is an attempt to harden the typing on virt_to_pfn() 2023-05-31 16:33:56 +02:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
io_uring io_uring: unlock sqd->lock before sq thread release CPU 2023-05-25 09:30:13 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Two fixes for debugobjects: 2023-05-28 07:15:33 -04:00
lib Two fixes for debugobjects: 2023-05-28 07:15:33 -04:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: fix zswap writeback race condition 2023-05-17 15:24:33 -07:00
net Networking fixes for 6.4-rc4, including fixes from bluetooth and bpf 2023-05-25 10:55:26 -07:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples/bpf: Drop unnecessary fallthrough 2023-05-16 19:44:05 +02:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security integrity-v6.4 2023-04-29 10:11:32 -07:00
sound ALSA: hda/realtek: Enable headset onLenovo M70/M90 2023-05-24 14:18:59 +02:00
tools cxl fixes for v6.4-rc4 2023-05-26 17:45:24 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt KVM: Fix vcpu_array[0] races 2023-05-19 13:56:26 -04:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.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 *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap mailmap: add entries for Nikolay Aleksandrov 2023-05-17 09:35:05 +01:00
.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: sctp: move Neil to CREDITS 2023-05-12 08:51:32 +01:00
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 ARM: SoC fixes for 6.4 2023-05-26 16:17:56 -07:00
Makefile Linux 6.4-rc4 2023-05-28 07:49:00 -04:00
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.