kernel/linux.git/arch/mips, branch v6.18.21

kbuild: Split .modinfo out from ELF_DETAILS

2026-03-12T11:09:44+00:00

commit 8678591b47469fe16357234efef9b260317b8be4 upstream. Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo to ELF_DETAILS while removing it from COMMON_DISCARDS, as it was needed in vmlinux.unstripped and ELF_DETAILS was present in all architecture specific vmlinux linker scripts. While this shuffle is fine for vmlinux, ELF_DETAILS and COMMON_DISCARDS may be used by other linker scripts, such as the s390 and x86 compressed boot images, which may not expect to have a .modinfo section. In certain circumstances, this could result in a bootloader failing to load the compressed kernel [1]. Commit ddc6cbef3ef1 ("s390/boot/vmlinux.lds.S: Ensure bzImage ends with SecureBoot trailer") recently addressed this for the s390 bzImage but the same bug remains for arm, parisc, and x86. The presence of .modinfo in the x86 bzImage was the root cause of the issue worked around with commit d50f21091358 ("kbuild: align modinfo section for Secureboot Authenticode EDK2 compat"). misc.c in arch/x86/boot/compressed includes lib/decompress_unzstd.c, which in turn includes lib/xxhash.c and its MODULE_LICENSE / MODULE_DESCRIPTION macros due to the STATIC definition. Split .modinfo out from ELF_DETAILS into its own macro and handle it in all vmlinux linker scripts. Discard .modinfo in the places where it was previously being discarded from being in COMMON_DISCARDS, as it has never been necessary in those uses. Cc: stable@vger.kernel.org Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Reported-by: Ed W Closes: https://lore.kernel.org/587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com/ [1] Tested-by: Ed W # x86_64 Link: https://patch.msgid.link/20260225-separate-modinfo-from-elf-details-v1-1-387ced6baf4b@kernel.org Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

MIPS: rb532: Fix MMIO UART resource registration

2026-03-04T12:21:25+00:00

[ Upstream commit e93bb4b76cfefb302534246e892c7667491cb8cc ] Since commit 6e690d54cfa8 ("serial: 8250: fix return error code in serial8250_request_std_resource()"), registering an 8250 MMIO port without mapbase no longer works, as the resource range is derived from mapbase/mapsize. Populate mapbase and mapsize accordingly. Also drop ugly membase KSEG1 pointer and set UPF_IOREMAP instead, letting the 8250 core perform the ioremap. Fixes: 6e690d54cfa8 ("serial: 8250: fix return error code in serial8250_request_std_resource()") Cc: stable@vger.kernel.org Reported-by: Waldemar Brodkorb Link: https://lore.kernel.org/linux-mips/aX-d0ShTplHKZT33@waldemar-brodkorb.de/ Signed-off-by: Jiaxun Yang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Loongson2ef: Use pcibios_align_resource() to block io range

2026-03-04T12:21:23+00:00

[ Upstream commit 32ec465103527ede09b640cd0ab0636dc58827fb ] Loongson2ef reserves io range below 0x4000 (LOONGSON_PCI_IO_START) while ISA-mode only IDE controller on the south bridge still has a hard dependency on ISA IO ports. The reservation was done by lifting loongson_pci_io_resource.start onto 0x4000. Prior to commit ae81aad5c2e1 ("MIPS: PCI: Use pci_enable_resources()"), the arch specific pcibios_enable_resources() did not check if the resources were claimed, which diverges from what PCI core checks, effectively hiding the fact that IDE IO resources were not properly within the resource tree. After starting to use pcibios_enable_resources() from PCI core, enabling IDE controller fails: pata_cs5536 0000:00:0e.2: BAR 0 [io 0x01f0-0x01f7]: not claimed; can't enable device pata_cs5536 0000:00:0e.2: probe with driver pata_cs5536 failed with error -22 MIPS PCI code already has support for enforcing lower bounds using PCIBIOS_MIN_IO in pcibios_align_resource() without altering the IO window start address itself. Make Loongson2ef PCI code use PCIBIOS_MIN_IO too. Fixes: ae81aad5c2e1 ("MIPS: PCI: Use pci_enable_resources()") Cc: stable@vger.kernel.org Tested-by: Beiyan Yun Tested-by: Yao Zi Signed-off-by: Rong Zhang Acked-by: Jiaxun Yang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Loongson2ef: Register PCI controller in early stage

2026-03-04T12:21:22+00:00

[ Upstream commit 6a00c043af07492502ba7a2263ddc4cdb01b66a7 ] We are about to set loongson_pci_io_resource.start to 0 and adopt PCIBIOS_MIN_IO. As the first step, PCI controller needs to be registered in early stage to make it the root of other resources (e.g., i8259) and prevent resource conflicts. Register it in plat_mem_setup() instead of arch_initcall(). Fixes: ae81aad5c2e1 ("MIPS: PCI: Use pci_enable_resources()") Cc: stable@vger.kernel.org Tested-by: Beiyan Yun Tested-by: Yao Zi Signed-off-by: Rong Zhang Acked-by: Jiaxun Yang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Loongson: Make cpumask_of_node() robust against NUMA_NO_NODE

2026-03-04T12:20:37+00:00

[ Upstream commit d55d3fe2d1470ac5b6e93efe7998b728013c9fc8 ] The arch definition of cpumask_of_node() cannot handle NUMA_NO_NODE - which is a valid index - so add a check for this. Signed-off-by: John Garry Reviewed-by: Huacai Chen Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Work around LLVM bug when gp is used as global register variable

2026-02-26T22:59:45+00:00

commit 30bfc2d6a1132a89a5f1c3b96c59cf3e4d076ea3 upstream. On MIPS, __current_thread_info is defined as global register variable locating in $gp, and is simply assigned with new address during kernel relocation. This however is broken with LLVM, which always restores $gp if it finds $gp is clobbered in any form, including when intentionally through a global register variable. This is against GCC's documentation[1], which requires a callee-saved register used as global register variable not to be restored if it's clobbered. As a result, $gp will continue to point to the unrelocated kernel after the epilog of relocate_kernel(), leading to an early crash in init_idle, [ 0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000000000000000, epc == ffffffff81afada8, ra == ffffffff81afad90 [ 0.000000] Oops[#1]: [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Tainted: G W 6.19.0-rc5-00262-gd3eeb99bbc99-dirty #188 VOLUNTARY [ 0.000000] Tainted: [W]=WARN [ 0.000000] Hardware name: loongson,loongson64v-4core-virtio [ 0.000000] $ 0 : 0000000000000000 0000000000000000 0000000000000001 0000000000000000 [ 0.000000] $ 4 : ffffffff80b80ec0 ffffffff80b53d48 0000000000000000 00000000000f4240 [ 0.000000] $ 8 : 0000000000000100 ffffffff81d82f80 ffffffff81d82f80 0000000000000001 [ 0.000000] $12 : 0000000000000000 ffffffff81776f58 00000000000005da 0000000000000002 [ 0.000000] $16 : ffffffff80b80e40 0000000000000000 ffffffff80b81614 9800000005dfbe80 [ 0.000000] $20 : 00000000540000e0 ffffffff81980000 0000000000000000 ffffffff80f81c80 [ 0.000000] $24 : 0000000000000a26 ffffffff8114fb90 [ 0.000000] $28 : ffffffff80b50000 ffffffff80b53d40 0000000000000000 ffffffff81afad90 [ 0.000000] Hi : 0000000000000000 [ 0.000000] Lo : 0000000000000000 [ 0.000000] epc : ffffffff81afada8 init_idle+0x130/0x270 [ 0.000000] ra : ffffffff81afad90 init_idle+0x118/0x270 [ 0.000000] Status: 540000e2 KX SX UX KERNEL EXL [ 0.000000] Cause : 00000008 (ExcCode 02) [ 0.000000] BadVA : 0000000000000000 [ 0.000000] PrId : 00006305 (ICT Loongson-3) [ 0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000) [ 0.000000] Stack : 9800000005dfbf00 ffffffff8178e950 0000000000000000 0000000000000000 [ 0.000000] 0000000000000000 ffffffff81970000 000000000000003f ffffffff810a6528 [ 0.000000] 0000000000000001 9800000005dfbe80 9800000005dfbf00 ffffffff81980000 [ 0.000000] ffffffff810a6450 ffffffff81afb6c0 0000000000000000 ffffffff810a2258 [ 0.000000] ffffffff81d82ec8 ffffffff8198d010 ffffffff81b67e80 ffffffff8197dd98 [ 0.000000] ffffffff81d81c80 ffffffff81930000 0000000000000040 0000000000000000 [ 0.000000] 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 0.000000] 0000000000000000 000000000000009e ffffffff9fc01000 0000000000000000 [ 0.000000] 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 0.000000] 0000000000000000 ffffffff81ae86dc ffffffff81b3c741 0000000000000002 [ 0.000000] ... [ 0.000000] Call Trace: [ 0.000000] [] init_idle+0x130/0x270 [ 0.000000] [] sched_init+0x5c8/0x6c0 [ 0.000000] [] start_kernel+0x27c/0x7a8 This bug has been reported to LLVM[2] and affects version from (at least) 18 to 21. Let's work around this by using inline assembly to assign $gp before a fix is widely available. Cc: stable@vger.kernel.org Link: https://gcc.gnu.org/onlinedocs/gcc-15.2.0/gcc/Global-Register-Variables.html # [1] Link: https://github.com/llvm/llvm-project/issues/176546 # [2] Signed-off-by: Yao Zi Acked-by: Nathan Chancellor Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

mips: LOONGSON32: drop a dangling Kconfig symbol

2026-02-26T22:59:35+00:00

[ Upstream commit d463fc5ca1ace0b2e8bb764df04fc12ecd6f8e2b ] CPU_HAS_LOAD_STORE_LR is not used anywhere in the kernel sources, so drop it. Fixes: 85c4354076ca ("MIPS: loongson32: Switch to generic core") Signed-off-by: Randy Dunlap Reviewed-by: Keguang Zhang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

mips: fix HIGHMEM initialization

2026-01-23T10:21:20+00:00

[ Upstream commit f171b55f1441294344b86edfeaa575ea9673fd23 ] Commit 6faea3422e3b ("arch, mm: streamline HIGHMEM freeing") overzealously removed mem_init_free_highmem() function that beside freeing high memory pages checked for CPU support for high memory as a prerequisite. Partially restore mem_init_free_highmem() with a new highmem_init() name and make it discard high memory in case there is no CPU support for it. Link: https://lkml.kernel.org/r/20251231105701.519711-1-rppt@kernel.org Fixes: 6faea3422e3b ("arch, mm: streamline HIGHMEM freeing") Signed-off-by: Mike Rapoport (Microsoft) Reported-by: Markus Stockhausen Cc: Chris Packham Cc: Hauke Mehrtens Cc: Jonas Jelonek Cc: Thomas Bogendoerfer Cc: Thomas Gleinxer Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

MIPS: ftrace: Fix memory corruption when kernel is located beyond 32 bits

2026-01-02T11:57:03+00:00

[ Upstream commit 36dac9a3dda1f2bae343191bc16b910c603cac25 ] Since commit e424054000878 ("MIPS: Tracing: Reduce the overhead of dynamic Function Tracer"), the macro UASM_i_LA_mostly has been used, and this macro can generate more than 2 instructions. At the same time, the code in ftrace assumes that no more than 2 instructions can be generated, which is why it stores them in an int[2] array. However, as previously noted, the macro UASM_i_LA_mostly (and now UASM_i_LA) causes a buffer overflow when _mcount is beyond 32 bits. This leads to corruption of the variables located in the __read_mostly section. This corruption was observed because the variable __cpu_primary_thread_mask was corrupted, causing a hang very early during boot. This fix prevents the corruption by avoiding the generation of instructions if they could exceed 2 instructions in length. Fortunately, insn_la_mcount is only used if the instrumented code is located outside the kernel code section, so dynamic ftrace can still be used, albeit in a more limited scope. This is still preferable to corrupting memory and/or crashing the kernel. Signed-off-by: Gregory CLEMENT Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Fix a reference leak bug in ip22_check_gio()

2026-01-02T11:56:52+00:00

[ Upstream commit 680ad315caaa2860df411cb378bf3614d96c7648 ] If gio_device_register fails, gio_dev_put() is required to drop the gio_dev device reference. Fixes: e84de0c61905 ("MIPS: GIO bus support for SGI IP22/28") Signed-off-by: Haoxiang Li Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin