linux-stable.git/arch/loongarch/kernel/setup.c, branch linux-rolling-stable

LoongArch: Add PIO for early access before ACPI PCI root register

2026-07-18T14:55:16+00:00

commit 6061e65f95713b01f4313cda6637dfe3aa5412b4 upstream.

For ACPI system we suppose the ISA/LPC PIO range is registered together
with PCI root bridge. But the fact is there may be some early access to
the ISA/LPC PIO range before ACPI PCI root register (most of them are
due to abnormal BIOS). Unconditionally register the ISA/LPC PIO range
usually causes ACPI PCI root register fail because of the address range
confliction. So we add a pair of helpers: acpi_add_early_pio() to add
PIO for early access, and acpi_remove_early_pio() to remove PIO before
PCI root register. Since acpi_remove_early_pio() may be called multiple
times, we add an acpi_pio flag to ensure PIO be removed only once.

Cc: 
Tested-by: Yuanzhen Gan 
Signed-off-by: Huacai Chen 
Signed-off-by: Greg Kroah-Hartman

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook

Merge tag 'loongarch-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2026-02-14T20:47:15+00:00

Pull LoongArch updates from Huacai Chen:
 - Select HAVE_CMPXCHG_{LOCAL,DOUBLE}
 - Add 128-bit atomic cmpxchg support
 - Add HOTPLUG_SMT implementation
 - Wire up memfd_secret system call
 - Fix boot errors and unwind errors for KASAN
 - Use BPF prog pack allocator and add BPF arena support
 - Update dts files to add nand controllers
 - Some bug fixes and other small changes

* tag 'loongarch-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: dts: loongson-2k1000: Add nand controller support
  LoongArch: dts: loongson-2k0500: Add nand controller support
  LoongArch: BPF: Implement bpf_addr_space_cast instruction
  LoongArch: BPF: Implement PROBE_MEM32 pseudo instructions
  LoongArch: BPF: Use BPF prog pack allocator
  LoongArch: Use IS_ERR_PCPU() macro for KGDB
  LoongArch: Rework KASAN initialization for PTW-enabled systems
  LoongArch: Disable instrumentation for setup_ptwalker()
  LoongArch: Remove some extern variables in source files
  LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT
  LoongArch: Handle percpu handler address for ORC unwinder
  LoongArch: Use %px to print unmodified unwinding address
  LoongArch: Prefer top-down allocation after arch_mem_init()
  LoongArch: Add HOTPLUG_SMT implementation
  LoongArch: Make cpumask_of_node() robust against NUMA_NO_NODE
  LoongArch: Wire up memfd_secret system call
  LoongArch: Replace seq_printf() with seq_puts() for simple strings
  LoongArch: Add 128-bit atomic cmpxchg support
  LoongArch: Add detection for SC.Q support
  LoongArch: Select HAVE_CMPXCHG_LOCAL in Kconfig

LoongArch: Prefer top-down allocation after arch_mem_init()

2026-02-10T11:31:13+00:00

Currently we use bottom-up allocation after sparse_init(), the reason is
sparse_init() need a lot of memory, and bottom-up allocation may exhaust
precious low memory (below 4GB). On the other hand, SWIOTLB and CMA need
low memories for DMA32, so swiotlb_init() and dma_contiguous_reserve()
need bottom-up allocation.

Since swiotlb_init() and dma_contiguous_reserve() are both called in
arch_mem_init(), we no longer need bottom-up allocation after that. So
we set the allocation policy to top-down at the end of arch_mem_init(),
in order to avoid later memory allocations (such as KASAN) exhaust low
memory.

This solve at least two problems:
1. Some buggy BIOSes use 0xfd000000~0xfe000000 for secondary CPUs, but
   didn't reserve this range, which causes smpboot failures.
2. Some DMA32 devices, such as Loongson-DRM and OHCI, cannot work with
   KASAN enabled.

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen

arch, mm: consolidate initialization of SPARSE memory model

2026-01-27T04:02:18+00:00

Every architecture calls sparse_init() during setup_arch() although the
data structures created by sparse_init() are not used until the
initialization of the core MM.

Beside the code duplication, calling sparse_init() from architecture
specific code causes ordering differences of vmemmap and HVO
initialization on different architectures.

Move the call to sparse_init() from architecture specific code to
free_area_init() to ensure that vmemmap and HVO initialization order is
always the same.

Link: https://lkml.kernel.org/r/20260111082105.290734-25-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Cc: Alexander Gordeev 
Cc: Alex Shi 
Cc: Andreas Larsson 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: David Hildenbrand 
Cc: David S. Miller 
Cc: Dinh Nguyen 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Johannes Berg 
Cc: John Paul Adrian Glaubitz 
Cc: Jonathan Corbet 
Cc: Klara Modin 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Magnus Lindholm 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Michal Simek 
Cc: Muchun Song 
Cc: Oscar Salvador 
Cc: Palmer Dabbelt 
Cc: Pratyush Yadav 
Cc: Richard Weinberger 
Cc: "Ritesh Harjani (IBM)" 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Suren Baghdasaryan 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

arch, mm: consolidate initialization of nodes, zones and memory map

2026-01-27T04:02:18+00:00

To initialize node, zone and memory map data structures every architecture
calls free_area_init() during setup_arch() and passes it an array of zone
limits.

Beside code duplication it creates "interesting" ordering cases between
allocation and initialization of hugetlb and the memory map.  Some
architectures allocate hugetlb pages very early in setup_arch() in certain
cases, some only create hugetlb CMA areas in setup_arch() and sometimes
hugetlb allocations happen mm_core_init().

With arch_zone_limits_init() helper available now on all architectures it
is no longer necessary to call free_area_init() from architecture setup
code.  Rather core MM initialization can call arch_zone_limits_init() in a
single place.

This allows to unify ordering of hugetlb vs memory map allocation and
initialization.

Remove the call to free_area_init() from architecture specific code and
place it in a new mm_core_init_early() function that is called immediately
after setup_arch().

After this refactoring it is possible to consolidate hugetlb allocations
and eliminate differences in ordering of hugetlb and memory map
initialization among different architectures.

As the first step of this consolidation move hugetlb_bootmem_alloc() to
mm_core_early_init().

Link: https://lkml.kernel.org/r/20260111082105.290734-24-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) 
Cc: Alexander Gordeev 
Cc: Alex Shi 
Cc: Andreas Larsson 
Cc: "Borislav Petkov (AMD)" 
Cc: Catalin Marinas 
Cc: David Hildenbrand 
Cc: David S. Miller 
Cc: Dinh Nguyen 
Cc: Geert Uytterhoeven 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Johannes Berg 
Cc: John Paul Adrian Glaubitz 
Cc: Jonathan Corbet 
Cc: Klara Modin 
Cc: Liam Howlett 
Cc: Lorenzo Stoakes 
Cc: Magnus Lindholm 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Michal Simek 
Cc: Muchun Song 
Cc: Oscar Salvador 
Cc: Palmer Dabbelt 
Cc: Pratyush Yadav 
Cc: Richard Weinberger 
Cc: "Ritesh Harjani (IBM)" 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Suren Baghdasaryan 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

LoongArch: Correct the calculation logic of thread_count

2025-12-06T02:39:49+00:00

For thread_count, the current calculation method has a maximum of 255,
which may not be sufficient in the future. Therefore, we are correcting
it now.

Reference: SMBIOS Specification, 7.5 Processor Information (Type 4)[1]

[1]: https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.9.0.pdf

Cc: stable@vger.kernel.org
Signed-off-by: Qiang Ma 
Signed-off-by: Huacai Chen

LoongArch: Consolidate max_pfn & max_low_pfn calculation

2025-11-10T00:37:06+00:00

Now there 5 places which calculate max_pfn & max_low_pfn:
1. in fdt_setup() for FDT systems;
2. in memblock_init() for ACPI systems;
3. in init_numa_memory() for NUMA systems;
4. in arch_mem_init() to recalculate for "mem=" cmdline;
5. in paging_init() to recalculate for NUMA systems.

Since memblock_init() is called both for ACPI and FDT systems, move the
calculation out of the for_each_efi_memory_desc() loop can eliminate the
first case. The last case is very questionable (may be derived from the
MIPS/Loongson code) and breaks the "mem=" cmdline, so should be removed.
And then the NUMA version of paging_init() can be also eliminated.

After consolidation there are 3 places of calculation:
1. in memblock_init() for both ACPI and FDT systems;
2. in init_numa_memory() to recalculate for NUMA systems;
3. in arch_mem_init() to recalculate for the "mem=" cmdline.

For all cases the calculation is:
max_pfn = PFN_DOWN(memblock_end_of_DRAM());
max_low_pfn = min(PFN_DOWN(HIGHMEM_START), max_pfn);

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen

LoongArch: Init acpi_gbl_use_global_lock to false

2025-10-02T14:38:57+00:00

Init acpi_gbl_use_global_lock to false, in order to void error messages
during boot phase:

 ACPI Error: Could not enable GlobalLock event (20240827/evxfevnt-182)
 ACPI Error: No response from Global Lock hardware, disabling lock (20240827/evglock-59)

Fixes: 628c3bb40e9a8cefc0a6 ("LoongArch: Add boot and setup routines")
Signed-off-by: Huacai Chen

Merge tag 'loongarch-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2025-08-08T03:36:48+00:00

Pull LoongArch updates from Huacai Chen:

 - Complete KSave registers definition

 - Support the mem= kernel parameter

 - Support BPF dynamic modification & trampoline

 - Add MMC/SDIO controller nodes in dts

 - Some bug fixes and other small changes

* tag 'loongarch-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: vDSO: Remove -nostdlib complier flag
  LoongArch: dts: Add eMMC/SDIO controller support to Loongson-2K2000
  LoongArch: dts: Add SDIO controller support to Loongson-2K1000
  LoongArch: dts: Add SDIO controller support to Loongson-2K0500
  LoongArch: BPF: Set bpf_jit_bypass_spec_v1/v4()
  LoongArch: BPF: Fix the tailcall hierarchy
  LoongArch: BPF: Fix jump offset calculation in tailcall
  LoongArch: BPF: Add struct ops support for trampoline
  LoongArch: BPF: Add basic bpf trampoline support
  LoongArch: BPF: Add dynamic code modification support
  LoongArch: BPF: Rename and refactor validate_code()
  LoongArch: Add larch_insn_gen_{beq,bne} helpers
  LoongArch: Don't use %pK through printk() in unwinder
  LoongArch: Avoid in-place string operation on FDT content
  LoongArch: Support mem= kernel parameter
  LoongArch: Make relocate_new_kernel_size be a .quad value
  LoongArch: Complete KSave registers definition