kernel/linux.git/arch/loongarch/include/asm, branch v6.1.174

LoongArch: Give more information if kmem access failed

2026-03-25T10:03:12+00:00

commit a47f0754bdd01f971c9715acdbdd3a07515c8f83 upstream. If memory access such as copy_{from, to}_kernel_nofault() failed, its users do not know what happened, so it is very useful to print the exception code for such cases. Furthermore, it is better to print the caller function to know where is the entry. Here are the low level call chains: copy_from_kernel_nofault() copy_from_kernel_nofault_loop() __get_kernel_nofault() copy_to_kernel_nofault() copy_to_kernel_nofault_loop() __put_kernel_nofault() Cc: stable@vger.kernel.org Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Make cpumask_of_node() robust against NUMA_NO_NODE

2026-03-04T12:20:53+00:00

[ Upstream commit 94b0c831eda778ae9e4f2164a8b3de485d8977bb ] The arch definition of cpumask_of_node() cannot handle NUMA_NO_NODE - which is a valid index - so add a check for this. Cc: stable@vger.kernel.org Signed-off-by: John Garry Signed-off-by: Huacai Chen Signed-off-by: Sasha Levin

LoongArch: Use pmd()/pte() for swap entry conversions

2026-01-11T14:19:10+00:00

commit 4a71df151e703b5e7e85b33369cee59ef2665e61 upstream. The __pmd() and __pte() helper macros provide the correct initialization syntax and abstraction for the pmd_t and pte_t types. Use __pmd() to fix follow warning about __swp_entry_to_pmd() with gcc-15 under specific configs [1] : In file included from ./include/linux/pgtable.h:6, from ./include/linux/mm.h:31, from ./include/linux/pagemap.h:8, from arch/loongarch/mm/init.c:14: ./include/linux/swapops.h: In function ‘swp_entry_to_pmd’: ./arch/loongarch/include/asm/pgtable.h:302:34: error: missing braces around initializer [-Werror=missing-braces] 302 | #define __swp_entry_to_pmd(x) ((pmd_t) { (x).val | _PAGE_HUGE }) | ^ ./include/linux/swapops.h:559:16: note: in expansion of macro ‘__swp_entry_to_pmd’ 559 | return __swp_entry_to_pmd(arch_entry); | ^~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors Also update __swp_entry_to_pte() to use __pte() for consistency. [1]. https://download.01.org/0day-ci/archive/20251119/202511190316.luI90kAo-lkp@intel.com/config Cc: stable@vger.kernel.org Signed-off-by: Yuli Wang Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Let {pte,pmd}_modify() record the status of _PAGE_DIRTY

2025-12-06T21:12:35+00:00

commit a073d637c8cfbfbab39b7272226a3fbf3b887580 upstream. Now if the PTE/PMD is dirty with _PAGE_DIRTY but without _PAGE_MODIFIED, after {pte,pmd}_modify() we lose _PAGE_DIRTY, then {pte,pmd}_dirty() return false and lead to data loss. This can happen in certain scenarios such as HW PTW doesn't set _PAGE_MODIFIED automatically, so here we need _PAGE_MODIFIED to record the dirty status (_PAGE_DIRTY). The new modification involves checking whether the original PTE/PMD has the _PAGE_DIRTY flag. If it exists, the _PAGE_MODIFIED bit is also set, ensuring that the {pte,pmd}_dirty() interface can always return accurate information. Cc: stable@vger.kernel.org Co-developed-by: Liupu Wang Signed-off-by: Liupu Wang Signed-off-by: Tianyang Zhang Signed-off-by: Greg Kroah-Hartman

LoongArch: Align ACPI structures if ARCH_STRICT_ALIGN enabled

2025-09-25T08:58:52+00:00

commit a9d13433fe17be0e867e51e71a1acd2731fbef8d upstream. ARCH_STRICT_ALIGN is used for hardware without UAL, now it only control the -mstrict-align flag. However, ACPI structures are packed by default so will cause unaligned accesses. To avoid this, define ACPI_MISALIGNMENT_NOT_SUPPORTED in asm/acenv.h to align ACPI structures if ARCH_STRICT_ALIGN enabled. Cc: stable@vger.kernel.org Reported-by: Binbin Zhou Suggested-by: Xi Ruoyao Suggested-by: Jiaxun Yang Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Avoid using $r0/$r1 as "mask" for csrxchg

2025-06-27T10:07:36+00:00

commit 52c22661c79a7b6af7fad9f77200738fc6c51878 upstream. When building kernel with LLVM there are occasionally such errors: In file included from ./include/linux/spinlock.h:59: In file included from ./include/linux/irqflags.h:17: arch/loongarch/include/asm/irqflags.h:38:3: error: must not be $r0 or $r1 38 | "csrxchg %[val], %[mask], %[reg]\n\t" | ^ :1:16: note: instantiated into assembly here 1 | csrxchg $a1, $ra, 0 | ^ To prevent the compiler from allocating $r0 or $r1 for the "mask" of the csrxchg instruction, the 'q' constraint must be used but Clang < 21 does not support it. So force to use $t0 in the inline asm, in order to avoid using $r0/$r1 while keeping the backward compatibility. Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/pull/141037 Reviewed-by: Yanteng Si Suggested-by: WANG Rui Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Fix MAX_REG_OFFSET calculation

2025-05-22T12:10:03+00:00

commit 90436d234230e9a950ccd87831108b688b27a234 upstream. Fix MAX_REG_OFFSET calculation, make it point to the last register in 'struct pt_regs' and not to the marker itself, which could allow regs_get_register() to return an invalid offset. Cc: stable@vger.kernel.org Fixes: 803b0fc5c3f2baa6e5 ("LoongArch: Add process management") Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Make regs_irqs_disabled() more clear

2025-05-02T05:46:55+00:00

[ Upstream commit bb0511d59db9b3e40c8d51f0d151ccd0fd44071d ] In the current code, the definition of regs_irqs_disabled() is actually "!(regs->csr_prmd & CSR_CRMD_IE)" because arch_irqs_disabled_flags() is defined as "!(flags & CSR_CRMD_IE)", it looks a little strange. Define regs_irqs_disabled() as !(regs->csr_prmd & CSR_PRMD_PIE) directly to make it more clear, no functional change. While at it, the return value of regs_irqs_disabled() is true or false, so change its type to reflect that and also make it always inline. Fixes: 803b0fc5c3f2 ("LoongArch: Add process management") Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen Signed-off-by: Sasha Levin

LoongArch: Increase ARCH_DMA_MINALIGN up to 16

2025-04-10T12:33:41+00:00

commit 4103cfe9dcb88010ae4911d3ff417457d1b6a720 upstream. ARCH_DMA_MINALIGN is 1 by default, but some LoongArch-specific devices (such as APBDMA) require 16 bytes alignment. When the data buffer length is too small, the hardware may make an error writing cacheline. Thus, it is dangerous to allocate a small memory buffer for DMA. It's always safe to define ARCH_DMA_MINALIGN as L1_CACHE_BYTES but unnecessary (kmalloc() need small memory objects). Therefore, just increase it to 16. Cc: stable@vger.kernel.org Tested-by: Binbin Zhou Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

LoongArch: Add architecture specific huge_pte_clear()

2024-12-14T18:54:32+00:00

commit 7cd1f5f77925ae905a57296932f0f9ef0dc364f8 upstream. When executing mm selftests run_vmtests.sh, there is such an error: BUG: Bad page state in process uffd-unit-tests pfn:00000 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x0 flags: 0xffff0000002000(reserved|node=0|zone=0|lastcpupid=0xffff) raw: 00ffff0000002000 ffffbf0000000008 ffffbf0000000008 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set Modules linked in: snd_seq_dummy snd_seq snd_seq_device rfkill vfat fat virtio_balloon efi_pstore virtio_net pstore net_failover failover fuse nfnetlink virtio_scsi virtio_gpu virtio_dma_buf dm_multipath efivarfs CPU: 2 UID: 0 PID: 1913 Comm: uffd-unit-tests Not tainted 6.12.0 #184 Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022 Stack : 900000047c8ac000 0000000000000000 9000000000223a7c 900000047c8ac000 900000047c8af690 900000047c8af698 0000000000000000 900000047c8af7d8 900000047c8af7d0 900000047c8af7d0 900000047c8af5b0 0000000000000001 0000000000000001 900000047c8af698 10b3c7d53da40d26 0000010000000000 0000000000000022 0000000fffffffff fffffffffe000000 ffff800000000000 000000000000002f 0000800000000000 000000017a6d4000 90000000028f8940 0000000000000000 0000000000000000 90000000025aa5e0 9000000002905000 0000000000000000 90000000028f8940 ffff800000000000 0000000000000000 0000000000000000 0000000000000000 9000000000223a94 000000012001839c 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1d ... Call Trace: [<9000000000223a94>] show_stack+0x5c/0x180 [<9000000001c3fd64>] dump_stack_lvl+0x6c/0xa0 [<900000000056aa08>] bad_page+0x1a0/0x1f0 [<9000000000574978>] free_unref_folios+0xbf0/0xd20 [<90000000004e65cc>] folios_put_refs+0x1a4/0x2b8 [<9000000000599a0c>] free_pages_and_swap_cache+0x164/0x260 [<9000000000547698>] tlb_batch_pages_flush+0xa8/0x1c0 [<9000000000547f30>] tlb_finish_mmu+0xa8/0x218 [<9000000000543cb8>] exit_mmap+0x1a0/0x360 [<9000000000247658>] __mmput+0x78/0x200 [<900000000025583c>] do_exit+0x43c/0xde8 [<9000000000256490>] do_group_exit+0x68/0x110 [<9000000000256554>] sys_exit_group+0x1c/0x20 [<9000000001c413b4>] do_syscall+0x94/0x130 [<90000000002216d8>] handle_syscall+0xb8/0x158 Disabling lock debugging due to kernel taint BUG: non-zero pgtables_bytes on freeing mm: -16384 On LoongArch system, invalid huge pte entry should be invalid_pte_table or a single _PAGE_HUGE bit rather than a zero value. And it should be the same with invalid pmd entry, since pmd_none() is called by function free_pgd_range() and pmd_none() return 0 by huge_pte_clear(). So single _PAGE_HUGE bit is also treated as a valid pte table and free_pte_range() will be called in free_pmd_range(). free_pmd_range() pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; free_pte_range(tlb, pmd, addr); } while (pmd++, addr = next, addr != end); Here invalid_pte_table is used for both invalid huge pte entry and pmd entry. Cc: stable@vger.kernel.org Fixes: 09cfefb7fa70 ("LoongArch: Add memory management") Signed-off-by: Bibo Mao Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman