mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-03-31 03:37:46 +08:00
47477c84b8
Pull s390 updates from Alexander Gordeev:
- Factor out handle_write() function and simplify 3215 console write
operation
- When 3170 terminal emulator is connected to the 3215 console driver
the boot time could be very long due to limited buffer space or
missing operator input. Add con3215_drop command line parameter and
con3215_drop sysfs attribute file to instruct the kernel drop console
data when such conditions are met
- Fix white space errors in 3215 console driver
- Move enum paiext_mode definition to a header file and rename it to
paievt_mode to indicate this is now used for several events. Rename
PAI_MODE_COUNTER to PAI_MODE_COUNTING to make consistent with
PAI_MODE_SAMPLING
- Simplify the logic of PMU pai_crypto mapped buffer reference counter
and make it consistent with PMU pai_ext
- Rename PMU pai_crypto mapped buffer structure member users to
active_events to make it consistent with PMU pai_ext
- Enable HUGETLB_PAGE_OPTIMIZE_VMEMMAP configuration option. This
results in saving of 12K per 1M hugetlb page (~1.2%) and 32764K per
2G hugetlb page (~1.6%)
- Use generic serial.h, bugs.h, shmparam.h and vga.h header files and
scrap s390-specific versions
- The generic percpu setup code does not expect the s390-like
implementation and emits a warning. To get rid of that warning and
provide sane CPU-to-node and CPU-to-CPU distance mappings implementat
a minimal version of setup_per_cpu_areas()
- Use kstrtobool() instead of strtobool() for re-IPL sysfs device
attributes
- Avoid unnecessary lookup of a pointer to MSI descriptor when setting
IRQ affinity for a PCI device
- Get rid of "an incompatible function type cast" warning by changing
debug_sprintf_format_fn() function prototype so it matches the
debug_format_proc_t function type
- Remove unused info_blk_hdr__pcpus() and get_page_state() functions
- Get rid of clang "unused unused insn cache ops function" warning by
moving s390_insn definition to a private header
- Get rid of clang "unused function" warning by making function
raw3270_state_final() only available if CONFIG_TN3270_CONSOLE is
enabled
- Use kstrobool() to parse sclp_con_drop parameter to make it identical
to the con3215_drop parameter and allow passing values like "yes" and
"true"
- Use sysfs_emit() for all SCLP sysfs show functions, which is the
current standard way to generate output strings
- Make SCLP con_drop sysfs attribute also writable and allow to change
its value during runtime. This makes SCLP console drop handling
consistent with the 3215 device driver
- Virtual and physical addresses are indentical on s390. However, there
is still a confusion when pointers are directly casted to physical
addresses or vice versa. Use correct address converters
virt_to_phys() and phys_to_virt() for s390 channel IO drivers
- Support for power managemant has been removed from s390 since quite
some time. Remove unused power managemant code from the appldata
device driver
- Allow memory tools like KASAN see memory accesses from the checksum
code. Switch to GENERIC_CSUM if KASAN is enabled, just like x86 does
- Add support of ECKD DASDs disks so it could be used as boot and dump
devices
- Follow checkpatch recommendations and use octal values instead of
S_IRUGO and S_IWUSR for dump device attributes in sysfs
- Changes to vx-insn.h do not cause a recompile of C files that use
asm(".include \"asm/vx-insn.h\"\n") magic to access vector
instruction macros from inline assemblies. Add wrapper include header
file to avoid this problem
- Use vector instruction macros instead of byte patterns to increase
register validation routine readability
- The current machine check register validation handling does not take
into account various scenarios and might lead to killing a wrong user
process or potentially ignore corrupted FPU registers. Simplify logic
of the machine check handler and stop the whole machine if the
previous context was kerenel mode. If the previous context was user
mode, kill the current task
- Introduce sclp_emergency_printk() function which can be used to emit
a message in emergency cases. It is supposed to be used in cases
where regular console device drivers may not work anymore, e.g.
unrecoverable machine checks
Keep the early Service-Call Control Block so it can also be used
after initdata has been freed to allow sclp_emergency_printk()
implementation
- In case a system will be stopped because of an unrecoverable machine
check error print the machine check interruption code to give a hint
of what went wrong
- Move storage error checking from the assembly entry code to C in
order to simplify machine check handling. Enter the handler with DAT
turned on, which simplifies the entry code even more
- The machine check extended save areas are allocated using a private
"nmi_save_areas" slab cache which guarantees a required power-of-two
alignment. Get rid of that cache in favour of kmalloc()
* tag 's390-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (38 commits)
s390/nmi: get rid of private slab cache
s390/nmi: move storage error checking back to C, enter with DAT on
s390/nmi: print machine check interruption code before stopping system
s390/sclp: introduce sclp_emergency_printk()
s390/sclp: keep sclp_early_sccb
s390/nmi: rework register validation handling
s390/nmi: use vector instruction macros instead of byte patterns
s390/vx: add vx-insn.h wrapper include file
s390/ipl: use octal values instead of S_* macros
s390/ipl: add eckd dump support
s390/ipl: add eckd support
vfio/ccw: identify CCW data addresses as physical
vfio/ccw: sort out physical vs virtual pointers usage
s390/checksum: support GENERIC_CSUM, enable it for KASAN
s390/appldata: remove power management callbacks
s390/cio: sort out physical vs virtual pointers usage
s390/sclp: allow to change sclp_console_drop during runtime
s390/sclp: convert to use sysfs_emit()
s390/sclp: use kstrobool() to parse sclp_con_drop parameter
s390/3270: make raw3270_state_final() depend on CONFIG_TN3270_CONSOLE
...
.. _readme:
Linux kernel release 6.x <http://kernel.org/>
=============================================
These are the release notes for Linux version 6. Read them carefully,
as they tell you what this is all about, explain how to install the
kernel, and what to do if something goes wrong.
What is Linux?
--------------
Linux is a clone of the operating system Unix, written from scratch by
Linus Torvalds with assistance from a loosely-knit team of hackers across
the Net. It aims towards POSIX and Single UNIX Specification compliance.
It has all the features you would expect in a modern fully-fledged Unix,
including true multitasking, virtual memory, shared libraries, demand
loading, shared copy-on-write executables, proper memory management,
and multistack networking including IPv4 and IPv6.
It is distributed under the GNU General Public License v2 - see the
accompanying COPYING file for more details.
On what hardware does it run?
-----------------------------
Although originally developed first for 32-bit x86-based PCs (386 or higher),
today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and
UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, Cell,
IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64 Xtensa, and
ARC architectures.
Linux is easily portable to most general-purpose 32- or 64-bit architectures
as long as they have a paged memory management unit (PMMU) and a port of the
GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has
also been ported to a number of architectures without a PMMU, although
functionality is then obviously somewhat limited.
Linux has also been ported to itself. You can now run the kernel as a
userspace application - this is called UserMode Linux (UML).
Documentation
-------------
- There is a lot of documentation available both in electronic form on
the Internet and in books, both Linux-specific and pertaining to
general UNIX questions. I'd recommend looking into the documentation
subdirectories on any Linux FTP site for the LDP (Linux Documentation
Project) books. This README is not meant to be documentation on the
system: there are much better sources available.
- There are various README files in the Documentation/ subdirectory:
these typically contain kernel-specific installation notes for some
drivers for example. Please read the
:ref:`Documentation/process/changes.rst <changes>` file, as it
contains information about the problems, which may result by upgrading
your kernel.
Installing the kernel source
----------------------------
- If you install the full sources, put the kernel tarball in a
directory where you have permissions (e.g. your home directory) and
unpack it::
xz -cd linux-6.x.tar.xz | tar xvf -
Replace "X" with the version number of the latest kernel.
Do NOT use the /usr/src/linux area! This area has a (usually
incomplete) set of kernel headers that are used by the library header
files. They should match the library, and not get messed up by
whatever the kernel-du-jour happens to be.
- You can also upgrade between 6.x releases by patching. Patches are
distributed in the xz format. To install by patching, get all the
newer patch files, enter the top level directory of the kernel source
(linux-6.x) and execute::
xz -cd ../patch-6.x.xz | patch -p1
Replace "x" for all versions bigger than the version "x" of your current
source tree, **in_order**, and you should be ok. You may want to remove
the backup files (some-file-name~ or some-file-name.orig), and make sure
that there are no failed patches (some-file-name# or some-file-name.rej).
If there are, either you or I have made a mistake.
Unlike patches for the 6.x kernels, patches for the 6.x.y kernels
(also known as the -stable kernels) are not incremental but instead apply
directly to the base 6.x kernel. For example, if your base kernel is 6.0
and you want to apply the 6.0.3 patch, you must not first apply the 6.0.1
and 6.0.2 patches. Similarly, if you are running kernel version 6.0.2 and
want to jump to 6.0.3, you must first reverse the 6.0.2 patch (that is,
patch -R) **before** applying the 6.0.3 patch. You can read more on this in
:ref:`Documentation/process/applying-patches.rst <applying_patches>`.
Alternatively, the script patch-kernel can be used to automate this
process. It determines the current kernel version and applies any
patches found::
linux/scripts/patch-kernel linux
The first argument in the command above is the location of the
kernel source. Patches are applied from the current directory, but
an alternative directory can be specified as the second argument.
- Make sure you have no stale .o files and dependencies lying around::
cd linux
make mrproper
You should now have the sources correctly installed.
Software requirements
---------------------
Compiling and running the 6.x kernels requires up-to-date
versions of various software packages. Consult
:ref:`Documentation/process/changes.rst <changes>` for the minimum version numbers
required and how to get updates for these packages. Beware that using
excessively old versions of these packages can cause indirect
errors that are very difficult to track down, so don't assume that
you can just update packages when obvious problems arise during
build or operation.
Build directory for the kernel
------------------------------
When compiling the kernel, all output files will per default be
stored together with the kernel source code.
Using the option ``make O=output/dir`` allows you to specify an alternate
place for the output files (including .config).
Example::
kernel source code: /usr/src/linux-6.x
build directory: /home/name/build/kernel
To configure and build the kernel, use::
cd /usr/src/linux-6.x
make O=/home/name/build/kernel menuconfig
make O=/home/name/build/kernel
sudo make O=/home/name/build/kernel modules_install install
Please note: If the ``O=output/dir`` option is used, then it must be
used for all invocations of make.
Configuring the kernel
----------------------
Do not skip this step even if you are only upgrading one minor
version. New configuration options are added in each release, and
odd problems will turn up if the configuration files are not set up
as expected. If you want to carry your existing configuration to a
new version with minimal work, use ``make oldconfig``, which will
only ask you for the answers to new questions.
- Alternative configuration commands are::
"make config" Plain text interface.
"make menuconfig" Text based color menus, radiolists & dialogs.
"make nconfig" Enhanced text based color menus.
"make xconfig" Qt based configuration tool.
"make gconfig" GTK+ based configuration tool.
"make oldconfig" Default all questions based on the contents of
your existing ./.config file and asking about
new config symbols.
"make olddefconfig"
Like above, but sets new symbols to their default
values without prompting.
"make defconfig" Create a ./.config file by using the default
symbol values from either arch/$ARCH/defconfig
or arch/$ARCH/configs/${PLATFORM}_defconfig,
depending on the architecture.
"make ${PLATFORM}_defconfig"
Create a ./.config file by using the default
symbol values from
arch/$ARCH/configs/${PLATFORM}_defconfig.
Use "make help" to get a list of all available
platforms of your architecture.
"make allyesconfig"
Create a ./.config file by setting symbol
values to 'y' as much as possible.
"make allmodconfig"
Create a ./.config file by setting symbol
values to 'm' as much as possible.
"make allnoconfig" Create a ./.config file by setting symbol
values to 'n' as much as possible.
"make randconfig" Create a ./.config file by setting symbol
values to random values.
"make localmodconfig" Create a config based on current config and
loaded modules (lsmod). Disables any module
option that is not needed for the loaded modules.
To create a localmodconfig for another machine,
store the lsmod of that machine into a file
and pass it in as a LSMOD parameter.
Also, you can preserve modules in certain folders
or kconfig files by specifying their paths in
parameter LMC_KEEP.
target$ lsmod > /tmp/mylsmod
target$ scp /tmp/mylsmod host:/tmp
host$ make LSMOD=/tmp/mylsmod \
LMC_KEEP="drivers/usb:drivers/gpu:fs" \
localmodconfig
The above also works when cross compiling.
"make localyesconfig" Similar to localmodconfig, except it will convert
all module options to built in (=y) options. You can
also preserve modules by LMC_KEEP.
"make kvm_guest.config" Enable additional options for kvm guest kernel
support.
"make xen.config" Enable additional options for xen dom0 guest kernel
support.
"make tinyconfig" Configure the tiniest possible kernel.
You can find more information on using the Linux kernel config tools
in Documentation/kbuild/kconfig.rst.
- NOTES on ``make config``:
- Having unnecessary drivers will make the kernel bigger, and can
under some circumstances lead to problems: probing for a
nonexistent controller card may confuse your other controllers.
- A kernel with math-emulation compiled in will still use the
coprocessor if one is present: the math emulation will just
never get used in that case. The kernel will be slightly larger,
but will work on different machines regardless of whether they
have a math coprocessor or not.
- The "kernel hacking" configuration details usually result in a
bigger or slower kernel (or both), and can even make the kernel
less stable by configuring some routines to actively try to
break bad code to find kernel problems (kmalloc()). Thus you
should probably answer 'n' to the questions for "development",
"experimental", or "debugging" features.
Compiling the kernel
--------------------
- Make sure you have at least gcc 5.1 available.
For more information, refer to :ref:`Documentation/process/changes.rst <changes>`.
- Do a ``make`` to create a compressed kernel image. It is also
possible to do ``make install`` if you have lilo installed to suit the
kernel makefiles, but you may want to check your particular lilo setup first.
To do the actual install, you have to be root, but none of the normal
build should require that. Don't take the name of root in vain.
- If you configured any of the parts of the kernel as ``modules``, you
will also have to do ``make modules_install``.
- Verbose kernel compile/build output:
Normally, the kernel build system runs in a fairly quiet mode (but not
totally silent). However, sometimes you or other kernel developers need
to see compile, link, or other commands exactly as they are executed.
For this, use "verbose" build mode. This is done by passing
``V=1`` to the ``make`` command, e.g.::
make V=1 all
To have the build system also tell the reason for the rebuild of each
target, use ``V=2``. The default is ``V=0``.
- Keep a backup kernel handy in case something goes wrong. This is
especially true for the development releases, since each new release
contains new code which has not been debugged. Make sure you keep a
backup of the modules corresponding to that kernel, as well. If you
are installing a new kernel with the same version number as your
working kernel, make a backup of your modules directory before you
do a ``make modules_install``.
Alternatively, before compiling, use the kernel config option
"LOCALVERSION" to append a unique suffix to the regular kernel version.
LOCALVERSION can be set in the "General Setup" menu.
- In order to boot your new kernel, you'll need to copy the kernel
image (e.g. .../linux/arch/x86/boot/bzImage after compilation)
to the place where your regular bootable kernel is found.
- Booting a kernel directly from a floppy without the assistance of a
bootloader such as LILO, is no longer supported.
If you boot Linux from the hard drive, chances are you use LILO, which
uses the kernel image as specified in the file /etc/lilo.conf. The
kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or
/boot/bzImage. To use the new kernel, save a copy of the old image
and copy the new image over the old one. Then, you MUST RERUN LILO
to update the loading map! If you don't, you won't be able to boot
the new kernel image.
Reinstalling LILO is usually a matter of running /sbin/lilo.
You may wish to edit /etc/lilo.conf to specify an entry for your
old kernel image (say, /vmlinux.old) in case the new one does not
work. See the LILO docs for more information.
After reinstalling LILO, you should be all set. Shutdown the system,
reboot, and enjoy!
If you ever need to change the default root device, video mode,
etc. in the kernel image, use your bootloader's boot options
where appropriate. No need to recompile the kernel to change
these parameters.
- Reboot with the new kernel and enjoy.
If something goes wrong
-----------------------
If you have problems that seem to be due to kernel bugs, please follow the
instructions at 'Documentation/admin-guide/reporting-issues.rst'.
Hints on understanding kernel bug reports are in
'Documentation/admin-guide/bug-hunting.rst'. More on debugging the kernel
with gdb is in 'Documentation/dev-tools/gdb-kernel-debugging.rst' and
'Documentation/dev-tools/kgdb.rst'.