linux.git/arch/arm/Kconfig, branch for-next

crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32

2024-11-15T06:43:48+00:00

Fixes boot failures on 6.9 on PPC_BOOK3S_32 machines using Open Firmware. 
On these machines, the kernel refuses to boot from non-zero
PHYSICAL_START, which occurs when CRASH_DUMP is on.

Since most PPC_BOOK3S_32 machines boot via Open Firmware, it should
default to off for them.  Users booting via some other mechanism can still
turn it on explicitly.

Does not change the default on any other architectures for the
time being.

Link: https://lkml.kernel.org/r/20240917163720.1644584-1-dave@vasilevsky.ca
Fixes: 75bc255a7444 ("crash: clean up kdump related config items")
Signed-off-by: Dave Vasilevsky 
Reported-by: Reimar Döffinger 
Closes: https://lists.debian.org/debian-powerpc/2024/07/msg00001.html
Acked-by: Michael Ellerman 	[powerpc]
Acked-by: Baoquan He 
Cc: "Eric W. Biederman" 
Cc: John Paul Adrian Glaubitz 
Cc: Reimar Döffinger 
Cc: 
Signed-off-by: Andrew Morton

Merge tag 'dma-mapping-6.12-2024-09-19' of git://git.infradead.org/users/hch/dma-mapping

2024-09-19T09:12:49+00:00

Pull dma-mapping updates from Christoph Hellwig:

 - support DMA zones for arm64 systems where memory starts at > 4GB
   (Baruch Siach, Catalin Marinas)

 - support direct calls into dma-iommu and thus obsolete dma_map_ops for
   many common configurations (Leon Romanovsky)

 - add DMA-API tracing (Sean Anderson)

 - remove the not very useful return value from various dma_set_* APIs
   (Christoph Hellwig)

 - misc cleanups and minor optimizations (Chen Y, Yosry Ahmed, Christoph
   Hellwig)

* tag 'dma-mapping-6.12-2024-09-19' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: reflow dma_supported
  dma-mapping: reliably inform about DMA support for IOMMU
  dma-mapping: add tracing for dma-mapping API calls
  dma-mapping: use IOMMU DMA calls for common alloc/free page calls
  dma-direct: optimize page freeing when it is not addressable
  dma-mapping: clearly mark DMA ops as an architecture feature
  vdpa_sim: don't select DMA_OPS
  arm64: mm: keep low RAM dma zone
  dma-mapping: don't return errors from dma_set_max_seg_size
  dma-mapping: don't return errors from dma_set_seg_boundary
  dma-mapping: don't return errors from dma_set_min_align_mask
  scsi: check that busses support the DMA API before setting dma parameters
  arm64: mm: fix DMA zone when dma-ranges is missing
  dma-mapping: direct calls for dma-iommu
  dma-mapping: call ->unmap_page and ->unmap_sg unconditionally
  arm64: support DMA zone above 4GB
  dma-mapping: replace zone_dma_bits by zone_dma_limit
  dma-mapping: use bit masking to check VM_DMA_COHERENT

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

2024-09-16T04:32:08+00:00

Pull ARM updates from Russell King:

 - clean up TTBCR magic numbers and use u32 for this register

 - fix clang issue in VFP code leading to kernel oops, caused by
   compiler instruction scheduling.

 - switch 32-bit Arm to use GENERIC_CPU_DEVICES and use the
   arch_cpu_is_hotpluggable() hook.

 - pass struct device to arm_iommu_create_mapping() and move over to use
   iommu_paging_domain_alloc() rather than iommu_domain_alloc()

 - make amba_bustype constant

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9418/1: dma-mapping: Use iommu_paging_domain_alloc()
  ARM: 9417/1: dma-mapping: Pass device to arm_iommu_create_mapping()
  ARM: 9416/1: amba: make amba_bustype constant
  ARM: 9412/1: Convert to arch_cpu_is_hotpluggable()
  ARM: 9411/1: Switch over to GENERIC_CPU_DEVICES using arch_register_cpu()
  ARM: 9410/1: vfp: Use asm volatile in fmrx/fmxr macros
  ARM: 9409/1: mmu: Do not use magic number for TTBCR settings

ARM: 9414/1: Fix build issue with LD_DEAD_CODE_DATA_ELIMINATION

2024-09-04T13:47:42+00:00

There is a build issue with LD segmentation fault, while
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is not enabled, as bellow.

scripts/link-vmlinux.sh: line 49:  3796 Segmentation fault
 (core dumped) ${ld} ${ldflags} -o ${output} ${wl}--whole-archive
 ${objs} ${wl}--no-whole-archive ${wl}--start-group
 ${libs} ${wl}--end-group ${kallsymso} ${btf_vmlinux_bin_o} ${ldlibs}

The error occurs in older versions of the GNU ld with version earlier
than 2.36. It makes most sense to have a minimum LD version as
a dependency for HAVE_LD_DEAD_CODE_DATA_ELIMINATION and eliminate
the impact of ".reloc  .text, R_ARM_NONE, ." when
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is not enabled.

Fixes: ed0f94102251 ("ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION")
Reported-by: Harith George 
Tested-by: Harith George 
Suggested-by: Arnd Bergmann 
Acked-by: Arnd Bergmann 
Signed-off-by: Yuntao Liu 
Link: https://lore.kernel.org/all/14e9aefb-88d1-4eee-8288-ef15d4a9b059@gmail.com/
Signed-off-by: Russell King (Oracle)

dma-mapping: clearly mark DMA ops as an architecture feature

2024-09-04T04:08:51+00:00

DMA ops are a helper for architectures and not for drivers to override
the DMA implementation.

Unfortunately driver authors keep ignoring this.  Make the fact more
clear by renaming the symbol to ARCH_HAS_DMA_OPS and having the two drivers
overriding their dma_ops depend on that.  These drivers should probably be
marked broken, but we can give them a bit of a grace period for that.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Thomas Gleixner 
Acked-by: Sakari Ailus  # for IPU6
Acked-by: Robin Murphy

ARM: 9411/1: Switch over to GENERIC_CPU_DEVICES using arch_register_cpu()

2024-08-20T10:18:49+00:00

Currently, almost all architectures have switched to GENERIC_CPU_DEVICES,
except for arm32. Also switch over to GENERIC_CPU_DEVICES, and provide an
arch_register_cpu() that populates the hotpluggable flag for arm32.

The struct cpu in struct cpuinfo_arm is never used directly, remove
it to use the one GENERIC_CPU_DEVICES provides.

This also has the effect of moving the registration of CPUs from subsys to
driver core initialisation, prior to any initcalls running.

Signed-off-by: Jinjie Ruan 
Signed-off-by: Russell King (Oracle)

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

2024-07-29T17:33:51+00:00

Pull ARM updates from Russell King:

 - ftrace: don't assume stack frames are contiguous in memory

 - remove unused mod_inwind_map structure

 - spelling fixes

 - allow use of LD dead code/data elimination

 - fix callchain_trace() return value

 - add support for stackleak gcc plugin

 - correct some reset asm function prototypes for CFI

[ Missed the merge window because Russell forgot to push out ]

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9408/1: mm: CFI: Fix some erroneous reset prototypes
  ARM: 9407/1: Add support for STACKLEAK gcc plugin
  ARM: 9406/1: Fix callchain_trace() return value
  ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
  ARM: 9403/1: Alpine: Spelling s/initialiing/initializing/
  ARM: 9402/1: Kconfig: Spelling s/Cortex A-/Cortex-A/
  ARM: 9400/1: Remove unused struct 'mod_unwind_map'

Merge tag 'kbuild-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2024-07-23T21:32:21+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Remove tristate choice support from Kconfig

 - Stop using the PROVIDE() directive in the linker script

 - Reduce the number of links for the combination of CONFIG_KALLSYMS and
   CONFIG_DEBUG_INFO_BTF

 - Enable the warning for symbol reference to .exit.* sections by
   default

 - Fix warnings in RPM package builds

 - Improve scripts/make_fit.py to generate a FIT image with separate
   base DTB and overlays

 - Improve choice value calculation in Kconfig

 - Fix conditional prompt behavior in choice in Kconfig

 - Remove support for the uncommon EMAIL environment variable in Debian
   package builds

 - Remove support for the uncommon "name " form for the DEBEMAIL
   environment variable

 - Raise the minimum supported GNU Make version to 4.0

 - Remove stale code for the absolute kallsyms

 - Move header files commonly used for host programs to scripts/include/

 - Introduce the pacman-pkg target to generate a pacman package used in
   Arch Linux

 - Clean up Kconfig

* tag 'kbuild-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (65 commits)
  kbuild: doc: gcc to CC change
  kallsyms: change sym_entry::percpu_absolute to bool type
  kallsyms: unify seq and start_pos fields of struct sym_entry
  kallsyms: add more original symbol type/name in comment lines
  kallsyms: use \t instead of a tab in printf()
  kallsyms: avoid repeated calculation of array size for markers
  kbuild: add script and target to generate pacman package
  modpost: use generic macros for hash table implementation
  kbuild: move some helper headers from scripts/kconfig/ to scripts/include/
  Makefile: add comment to discourage tools/* addition for kernel builds
  kbuild: clean up scripts/remove-stale-files
  kconfig: recursive checks drop file/lineno
  kbuild: rpm-pkg: introduce a simple changelog section for kernel.spec
  kallsyms: get rid of code for absolute kallsyms
  kbuild: Create INSTALL_PATH directory if it does not exist
  kbuild: Abort make on install failures
  kconfig: remove 'e1' and 'e2' macros from expression deduplication
  kconfig: remove SYMBOL_CHOICEVAL flag
  kconfig: add const qualifiers to several function arguments
  kconfig: call expr_eliminate_yn() at least once in expr_eliminate_dups()
  ...

treewide: change conditional prompt for choices to 'depends on'

2024-07-15T16:08:37+00:00

While Documentation/kbuild/kconfig-language.rst provides a brief
explanation, there are recurring confusions regarding the usage of a
prompt followed by 'if '. This conditional controls _only_ the
prompt.

A typical usage is as follows:

    menuconfig BLOCK
            bool "Enable the block layer" if EXPERT
            default y

When EXPERT=n, the prompt is hidden, but this config entry is still
active, and BLOCK is set to its default value 'y'. This is reasonable
because you are likely want to enable the block device support. When
EXPERT=y, the prompt is shown, allowing you to toggle BLOCK.

Please note that it is different from 'depends on EXPERT', which would
enable and disable the entire config entry.

However, this conditional prompt has never worked in a choice block.

The following two work in the same way: when EXPERT is disabled, the
choice block is entirely disabled.

[Test Code 1]

    choice
            prompt "choose" if EXPERT

    config A
            bool "A"

    config B
            bool "B"

    endchoice

[Test Code 2]

    choice
            prompt "choose"
            depends on EXPERT

    config A
            bool "A"

    config B
            bool "B"

    endchoice

I believe the first case should hide only the prompt, producing the
default:

   CONFIG_A=y
   # CONFIG_B is not set

The next commit will change (fix) the behavior of the conditional prompt
in choice blocks.

I see several choice blocks wrongly using a conditional prompt, where
'depends on' makes more sense.

To preserve the current behavior, this commit converts such misuses.

I did not touch the following entry in arch/x86/Kconfig:

    choice
            prompt "Memory split" if EXPERT
            default VMSPLIT_3G

This is truly the correct use of the conditional prompt; when EXPERT=n,
this choice block should silently select the reasonable VMSPLIT_3G,
although the resulting PAGE_OFFSET will not be affected anyway.

Presumably, the one in fs/jffs2/Kconfig is also correct, but I converted
it to 'depends on' to avoid any potential behavioral change.

Signed-off-by: Masahiro Yamada

ARM: Emulate one-byte cmpxchg

2024-07-04T20:32:41+00:00

Use the new cmpxchg_emu_u8() to emulate one-byte cmpxchg() on ARM systems
with ARCH == ARMv6K.

[ paulmck: Apply Arnd Bergmann and Nathan Chancellor feedback. ]
[ paulmck: Apply Linus Walleij feedback. ]

Reported-by: Mark Brown 
Closes: https://lore.kernel.org/all/54798f68-48f7-4c65-9cba-47c0bf175143@sirena.org.uk/
Reported-by: Naresh Kamboju 
Closes: https://lore.kernel.org/all/CA+G9fYuZ+pf6p8AXMZWtdFtX-gbG8HMaBKp=XbxcdzA_QeLkxQ@mail.gmail.com/
Signed-off-by: Paul E. McKenney 
Tested-by: Nathan Chancellor 
Reviewed-by: Linus Walleij 
Cc: "Russell King (Oracle)" 
Cc: Arnd Bergmann 
Cc: Andrew Davis 
Cc: Andrew Morton 
Cc: Eric DeVolder 
Cc: Rob Herring 
Cc: