futex: Ensure futex_atomic_cmpxchg_inatomic() is present

The boot-time detection of futex_atomic_cmpxchg_inatomic() has a bug on
some 32-bit arm builds, and Thomas Gleixner suggested that setting
CO

futex: Ensure futex_atomic_cmpxchg_inatomic() is present

The boot-time detection of futex_atomic_cmpxchg_inatomic() has a bug on
some 32-bit arm builds, and Thomas Gleixner suggested that setting
CONFIG_HAVE_FUTEX_CMPXCHG would avoid the problem, as it is always present
anyway.

Looking into which other architectures could do the same showed that almost
all architectures have it, the exceptions being:

- some old 32-bit MIPS uniprocessor cores without ll/sc
- one xtensa variant with no SMP
- 32-bit SPARC when built for SMP

Fix MIPS And Xtensa by rearranging the generic code to let it be used
as a fallback.

For SPARC, the SMP definition just ends up turning off futex anyway, so
this can be done at Kconfig time instead. Note that sparc32 glibc requires
the CASA instruction for its mutexes anyway, which is only available when
running on SPARCv9 or LEON CPUs, but needs to be implemented in the sparc32
kernel for those.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rich Felker <dalias@libc.org>
Link: https://lore.kernel.org/r/20211026100432.1730393-1-arnd@kernel.org

show more ...

Merge branch 'next' into for-linus

Prepare input updates for 5.12 merge window.

Merge tag 'v5.11' into next

Merge with mainline to get latest APIs and device tree bindings.

Merge branch 'for-5.11/elecom' into for-linus

- support for EX-G M-XGL20DLBK device, from YOSHIOKA Takuma

Merge remote-tracking branch 'spi/for-5.10' into spi-linus

Merge remote-tracking branch 'asoc/for-5.10' into asoc-linus

Merge branches 'for-next/kvm-build-fix', 'for-next/va-refactor', 'for-next/lto', 'for-next/mem-hotplug', 'for-next/cppc-ffh', 'for-next/pad-image-header', 'for-next/zone-dma-default-32-bit', 'for-nex

Merge branches 'for-next/kvm-build-fix', 'for-next/va-refactor', 'for-next/lto', 'for-next/mem-hotplug', 'for-next/cppc-ffh', 'for-next/pad-image-header', 'for-next/zone-dma-default-32-bit', 'for-next/signal-tag-bits' and 'for-next/cmdline-extended' into for-next/core

* for-next/kvm-build-fix:
: Fix KVM build issues with 64K pages
KVM: arm64: Fix build error in user_mem_abort()

* for-next/va-refactor:
: VA layout changes
arm64: mm: don't assume struct page is always 64 bytes
Documentation/arm64: fix RST layout of memory.rst
arm64: mm: tidy up top of kernel VA space
arm64: mm: make vmemmap region a projection of the linear region
arm64: mm: extend linear region for 52-bit VA configurations

* for-next/lto:
: Upgrade READ_ONCE() to RCpc acquire on arm64 with LTO
arm64: lto: Strengthen READ_ONCE() to acquire when CONFIG_LTO=y
arm64: alternatives: Remove READ_ONCE() usage during patch operation
arm64: cpufeatures: Add capability for LDAPR instruction
arm64: alternatives: Split up alternative.h
arm64: uaccess: move uao_* alternatives to asm-uaccess.h

* for-next/mem-hotplug:
: Memory hotplug improvements
arm64/mm/hotplug: Ensure early memory sections are all online
arm64/mm/hotplug: Enable MEM_OFFLINE event handling
arm64/mm/hotplug: Register boot memory hot remove notifier earlier
arm64: mm: account for hotplug memory when randomizing the linear region

* for-next/cppc-ffh:
: Add CPPC FFH support using arm64 AMU counters
arm64: abort counter_read_on_cpu() when irqs_disabled()
arm64: implement CPPC FFH support using AMUs
arm64: split counter validation function
arm64: wrap and generalise counter read functions

* for-next/pad-image-header:
: Pad Image header to 64KB and unmap it
arm64: head: tidy up the Image header definition
arm64/head: avoid symbol names pointing into first 64 KB of kernel image
arm64: omit [_text, _stext) from permanent kernel mapping

* for-next/zone-dma-default-32-bit:
: Default to 32-bit wide ZONE_DMA (previously reduced to 1GB for RPi4)
of: unittest: Fix build on architectures without CONFIG_OF_ADDRESS
mm: Remove examples from enum zone_type comment
arm64: mm: Set ZONE_DMA size based on early IORT scan
arm64: mm: Set ZONE_DMA size based on devicetree's dma-ranges
of: unittest: Add test for of_dma_get_max_cpu_address()
of/address: Introduce of_dma_get_max_cpu_address()
arm64: mm: Move zone_dma_bits initialization into zone_sizes_init()
arm64: mm: Move reserve_crashkernel() into mem_init()
arm64: Force NO_BLOCK_MAPPINGS if crashkernel reservation is required
arm64: Ignore any DMA offsets in the max_zone_phys() calculation

* for-next/signal-tag-bits:
: Expose the FAR_EL1 tag bits in siginfo
arm64: expose FAR_EL1 tag bits in siginfo
signal: define the SA_EXPOSE_TAGBITS bit in sa_flags
signal: define the SA_UNSUPPORTED bit in sa_flags
arch: provide better documentation for the arch-specific SA_* flags
signal: clear non-uapi flag bits when passing/returning sa_flags
arch: move SA_* definitions to generic headers
parisc: start using signal-defs.h
parisc: Drop parisc special case for __sighandler_t

* for-next/cmdline-extended:
: Add support for CONFIG_CMDLINE_EXTENDED
arm64: Extend the kernel command line from the bootloader
arm64: kaslr: Refactor early init command line parsing

show more ...

Merge remote-tracking branch 'origin/master' into perf/core

Further perf/core patches will depend on:

d3f7b1bb2040 ("mm/gup: fix gup_fast with dynamic page table folding")

which is already in Li

Merge remote-tracking branch 'origin/master' into perf/core

Further perf/core patches will depend on:

d3f7b1bb2040 ("mm/gup: fix gup_fast with dynamic page table folding")

which is already in Linus' tree.

show more ...

Merge tag 'v5.10-rc1' into kvmarm-master/next

Linux 5.10-rc1

Signed-off-by: Marc Zyngier <maz@kernel.org>

Merge branch 'linus' into perf/kprobes

Conflicts:
include/asm-generic/atomic-instrumented.h
kernel/kprobes.c

Use the upstream atomic-instrumented.h checksum, and pick
the kprobes version of kerne

Merge branch 'linus' into perf/kprobes

Conflicts:
include/asm-generic/atomic-instrumented.h
kernel/kprobes.c

Use the upstream atomic-instrumented.h checksum, and pick
the kprobes version of kernel/kprobes.c, which effectively
reverts this upstream workaround:

645f224e7ba2: ("kprobes: Tell lockdep about kprobe nesting")

Since the new code *should* be fine without nesting.

Knock on wood ...

Signed-off-by: Ingo Molnar <mingo@kernel.org>

show more ...

Merge drm/drm-next into drm-intel-next-queued

Catch up with v5.10-rc2 and drm-misc-next.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge branch 'core/urgent' into core/entry

Pick up the entry fix before further modifications.

Merge drm/drm-next into drm-misc-next

Daniel needs -rc2 in drm-misc-next to merge some patches

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge tag 'drm-intel-fixes-2020-10-29' into gvt-fixes

Backmerge for 5.10-rc1 to apply one extra APL fix.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Merge tag 'v5.10-rc1' into regulator-5.10

Linux 5.10-rc1

Merge tag 'v5.10-rc1' into spi-5.10

Linux 5.10-rc1

Merge tag 'v5.10-rc1' into asoc-5.10

Linux 5.10-rc1

Merge tag 'mips_5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Thomas Bogendoerfer:

- removed support for PNX833x alias NXT_STB22x

- included Ingenic So

Merge tag 'mips_5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Thomas Bogendoerfer:

- removed support for PNX833x alias NXT_STB22x

- included Ingenic SoC support into generic MIPS kernels

- added support for new Ingenic SoCs

- converted workaround selection to use Kconfig

- replaced old boot mem functions by memblock_*

- enabled COP2 usage in kernel for Loongson64 to make use
of 16byte load/stores possible

- cleanups and fixes

* tag 'mips_5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (92 commits)
MIPS: DEC: Restore bootmem reservation for firmware working memory area
MIPS: dec: fix section mismatch
bcm963xx_tag.h: fix duplicated word
mips: ralink: enable zboot support
MIPS: ingenic: Remove CPU_SUPPORTS_HUGEPAGES
MIPS: cpu-probe: remove MIPS_CPU_BP_GHIST option bit
MIPS: cpu-probe: introduce exclusive R3k CPU probe
MIPS: cpu-probe: move fpu probing/handling into its own file
MIPS: replace add_memory_region with memblock
MIPS: Loongson64: Clean up numa.c
MIPS: Loongson64: Select SMP in Kconfig to avoid build error
mips: octeon: Add Ubiquiti E200 and E220 boards
MIPS: SGI-IP28: disable use of ll/sc in kernel
MIPS: tx49xx: move tx4939_add_memory_regions into only user
MIPS: pgtable: Remove used PAGE_USERIO define
MIPS: alchemy: Share prom_init implementation
MIPS: alchemy: Fix build breakage, if TOUCHSCREEN_WM97XX is disabled
MIPS: process: include exec.h header in process.c
MIPS: process: Add prototype for function arch_dup_task_struct
MIPS: idle: Add prototype for function check_wait
...

show more ...

MIPS: Convert R10000_LLSC_WAR info a config option

Use a new config option to enabel R1000_LLSC workaound and remove
define from different war.h files.

Signed-off-by: Thomas Bogendoerfer <tsbogend@

MIPS: Convert R10000_LLSC_WAR info a config option

Use a new config option to enabel R1000_LLSC workaound and remove
define from different war.h files.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

show more ...

Merge branch 'master' into for-next

Sync with Linus' branch in order to be able to apply fixups
of more recent patches.

Merge branch 'next' into for-linus

Prepare input updates for 5.9 merge window.

Merge branch 'elan-i2c' into next

Bring in update to Elan touchpad driver to support newer touchpads with
higher resolution.

Merge branch 'for-5.8' into for-linus

Merge branch 'timers/drivers/timer-ti' into timers/drivers/next

Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

Pull RCU updates from Paul McKenney:

1. Miscellaneous fixes.
2. kfree_rcu() updates.

Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

Pull RCU updates from Paul McKenney:

1. Miscellaneous fixes.
2. kfree_rcu() updates.
3. Remove scheduler locking restriction
4. RCU-tasks update, including addition of RCU Tasks Trace for
BPF use and RCU Tasks Rude. (This branch is on top of #3 due
to overlap of changed code.)
5. RCU CPU stall warning updates.
6. Torture-test updates.

show more ...