linux-stable.git/arch/s390/Makefile, branch linux-rolling-stable

Merge tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2025-12-03T00:37:00+00:00

Pull s390 updates from Heiko Carstens:

 - Provide a new interface for dynamic configuration and deconfiguration
   of hotplug memory, allowing with and without memmap_on_memory
   support. This makes the way memory hotplug is handled on s390 much
   more similar to other architectures

 - Remove compat support. There shouldn't be any compat user space
   around anymore, therefore get rid of a lot of code which also doesn't
   need to be tested anymore

 - Add stackprotector support. GCC 16 will get new compiler options,
   which allow to generate code required for kernel stackprotector
   support

 - Merge pai_crypto and pai_ext PMU drivers into a new driver. This
   removes a lot of duplicated code. The new driver is also extendable
   and allows to support new PMUs

 - Add driver override support for AP queues

 - Rework and extend zcrypt and AP trace events to allow for tracing of
   crypto requests

 - Support block sizes larger than 65535 bytes for CCW tape devices

 - Since the rework of the virtual kernel address space the module area
   and the kernel image are within the same 4GB area. This eliminates
   the need of weak per cpu variables. Get rid of
   ARCH_MODULE_NEEDS_WEAK_PER_CPU

 - Various other small improvements and fixes

* tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (92 commits)
  watchdog: diag288_wdt: Remove KMSG_COMPONENT macro
  s390/entry: Use lay instead of aghik
  s390/vdso: Get rid of -m64 flag handling
  s390/vdso: Rename vdso64 to vdso
  s390: Rename head64.S to head.S
  s390/vdso: Use common STABS_DEBUG and DWARF_DEBUG macros
  s390: Add stackprotector support
  s390/modules: Simplify module_finalize() slightly
  s390: Remove KMSG_COMPONENT macro
  s390/percpu: Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
  s390/ap: Restrict driver_override versus apmask and aqmask use
  s390/ap: Rename mutex ap_perms_mutex to ap_attr_mutex
  s390/ap: Support driver_override for AP queue devices
  s390/ap: Use all-bits-one apmask/aqmask for vfio in_use() checks
  s390/debug: Update description of resize operation
  s390/syscalls: Switch to generic system call table generation
  s390/syscalls: Remove system call table pointer from thread_struct
  s390/uapi: Remove 31 bit support from uapi header files
  s390: Remove compat support
  tools: Remove s390 compat support
  ...

s390/vdso: Rename vdso64 to vdso

2025-11-25T14:28:07+00:00

Since compat is gone there is only a 64 bit vdso left.
Remove the superfluous "64" suffix everywhere.

Reviewed-by: Jens Remus 
Signed-off-by: Heiko Carstens

s390: Add stackprotector support

2025-11-24T10:45:21+00:00

Stackprotector support was previously unavailable on s390 because by
default compilers generate code which is not suitable for the kernel:
the canary value is accessed via thread local storage, where the address
of thread local storage is within access registers 0 and 1.

Using those registers also for the kernel would come with a significant
performance impact and more complicated kernel entry/exit code, since
access registers contents would have to be exchanged on every kernel entry
and exit.

With the upcoming gcc 16 release new compiler options will become available
which allow to generate code suitable for the kernel. [1]

Compiler option -mstack-protector-guard=global instructs gcc to generate
stackprotector code that refers to a global stackprotector canary value via
symbol __stack_chk_guard. Access to this value is guaranteed to occur via
larl and lgrl instructions.

Furthermore, compiler option -mstack-protector-guard-record generates a
section containing all code addresses that reference the canary value.

To allow for per task canary values the instructions which load the address
of __stack_chk_guard are patched so they access a lowcore field instead: a
per task canary value is available within the task_struct of each task, and
is written to the per-cpu lowcore location on each context switch.

Also add sanity checks and debugging option to be consistent with other
kernel code patching mechanisms.

Full debugging output can be enabled with the following kernel command line
options:

debug_stackprotector
bootdebug
ignore_loglevel
earlyprintk
dyndbg="file stackprotector.c +p"

Example debug output:

stackprot: 0000021e402d4eda: c010005a9ae3 -> c01f00070240

where ":  -> ".

[1] gcc commit 0cd1f03939d5 ("s390: Support global stack protector")

Reviewed-by: Sven Schnelle 
Signed-off-by: Heiko Carstens

s390/syscalls: Switch to generic system call table generation

2025-11-17T10:10:39+00:00

The s390 syscall.tbl format differs slightly from most others, and
therefore requires an s390 specific system call table generation
script.

With compat support gone use the opportunity to switch to generic
system call table generation. The abi for all 64 bit system calls is
now common, since there is no need to specify if system call entry
points are only for 64 bit anymore.

Furthermore create the system call table in C instead of assembler
code in order to get type checking for all system call functions
contained within the table.

Reviewed-by: Arnd Bergmann 
Signed-off-by: Heiko Carstens

s390: Remove compat support

2025-11-17T10:10:38+00:00

There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.

Reason for removal is code simplification and reduced test effort.

Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.

If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.

Reviewed-by: Arnd Bergmann 
Signed-off-by: Heiko Carstens

kbuild: Add '-fms-extensions' to areas with dedicated CFLAGS

2025-10-31T01:26:28+00:00

This is a follow up to commit c4781dc3d1cf ("Kbuild: enable
-fms-extensions") but in a separate change due to being substantially
different from the initial submission.

There are many places within the kernel that use their own CFLAGS
instead of the main KBUILD_CFLAGS, meaning code written with the main
kernel's use of '-fms-extensions' in mind that may be tangentially
included in these areas will result in "error: declaration does not
declare anything" messages from the compiler.

Add '-fms-extensions' to all these areas to ensure consistency, along
with -Wno-microsoft-anon-tag to silence clang's warning about use of the
extension that the kernel cares about using. parisc does not build with
clang so it does not need this warning flag. LoongArch does not need it
either because -W flags from KBUILD_FLAGS are pulled into cflags-vdso.

Reported-by: Christian Brauner 
Closes: https://lore.kernel.org/20251030-meerjungfrau-getrocknet-7b46eacc215d@brauner/
Reviewed-by: Christian Brauner 
Acked-by: Ard Biesheuvel 
Signed-off-by: Nathan Chancellor

s390: Add -Wno-pointer-sign to KBUILD_CFLAGS_DECOMPRESSOR

2025-09-29T11:52:08+00:00

If the decompressor is compiled with clang this can lead to the following
warning:

In file included from arch/s390/boot/startup.c:4:
...
In file included from ./include/linux/pgtable.h:6:
./arch/s390/include/asm/pgtable.h:2065:48: warning: passing 'unsigned long *' to parameter of type
      'long *' converts between pointers to integer types with different sign [-Wpointer-sign]
 2065 |                 value = __atomic64_or_barrier(PGSTE_PCL_BIT, ptr);

Add -Wno-pointer-sign to the decompressor compile flags, like it is also
done for the kernel. This is similar to what was done for x86 to address
the same problem [1].

[1] commit dca5203e3fe2 ("x86/boot: Add -Wno-pointer-sign to KBUILD_CFLAGS")

Cc: stable@vger.kernel.org
Reported-by: Gerd Bayer 
Signed-off-by: Heiko Carstens 
Reviewed-by: Alexander Gordeev 
Signed-off-by: Alexander Gordeev

s390: Allow to compile with z17 optimizations

2025-04-09T10:12:41+00:00

Add config and compile options which allow to compile with z17
optimizations if the compiler supports it. Add the
miscellaneous-instruction-extension 4 facility to the list of facilities
for z17.

Reviewed-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Heiko Carstens

Merge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2025-04-05T22:46:50+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Improve performance in gendwarfksyms

 - Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS

 - Support CONFIG_HEADERS_INSTALL for ARCH=um

 - Use more relative paths to sources files for better reproducibility

 - Support the loong64 Debian architecture

 - Add Kbuild bash completion

 - Introduce intermediate vmlinux.unstripped for architectures that need
   static relocations to be stripped from the final vmlinux

 - Fix versioning in Debian packages for -rc releases

 - Treat missing MODULE_DESCRIPTION() as an error

 - Convert Nios2 Makefiles to use the generic rule for built-in DTB

 - Add debuginfo support to the RPM package

* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
  kbuild: rpm-pkg: build a debuginfo RPM
  kconfig: merge_config: use an empty file as initfile
  nios2: migrate to the generic rule for built-in DTB
  rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
  kbuild: pacman-pkg: hardcode module installation path
  kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
  modpost: require a MODULE_DESCRIPTION()
  kbuild: make all file references relative to source root
  x86: drop unnecessary prefix map configuration
  kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
  kbuild: Add a help message for "headers"
  kbuild: deb-pkg: remove "version" variable in mkdebian
  kbuild: deb-pkg: fix versioning for -rc releases
  Documentation/kbuild: Fix indentation in modules.rst example
  x86: Get rid of Makefile.postlink
  kbuild: Create intermediate vmlinux build with relocations preserved
  kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
  kbuild: link-vmlinux.sh: Make output file name configurable
  kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
  Revert "kheaders: Ignore silly-rename files"
  ...

s390: Fix linker error when -no-pie option is unavailable

2025-03-31T10:20:39+00:00

The kernel build may fail if the linker does not support -no-pie option,
as it always included in LDFLAGS_vmlinux.

Error log:
s390-linux-ld: unable to disambiguate: -no-pie (did you mean --no-pie ?)

Although the GNU linker defaults to -no-pie, the ability to explicitly
specify this option was introduced in binutils 2.36.

Hence, fix it by adding -no-pie to LDFLAGS_vmlinux only when it is
available.

Cc: stable@vger.kernel.org
Fixes: 00cda11d3b2e ("s390: Compile kernel with -fPIC and link with -no-pie")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202503220342.T3fElO9L-lkp@intel.com/
Suggested-by: Jens Remus 
Reviewed-by: Jens Remus 
Signed-off-by: Sumanth Korikkar 
Signed-off-by: Vasily Gorbik