kernel/linux.git/arch/mips/mm, branch v5.15.208

MIPS: mm: Prevent a TLB shutdown on initial uniquification

2025-12-06T21:09:34+00:00

commit 9f048fa487409e364cf866c957cf0b0d782ca5a3 upstream. Depending on the particular CPU implementation a TLB shutdown may occur if multiple matching entries are detected upon the execution of a TLBP or the TLBWI/TLBWR instructions. Given that we don't know what entries we have been handed we need to be very careful with the initial TLB setup and avoid all these instructions. Therefore read all the TLB entries one by one with the TLBR instruction, bypassing the content addressing logic, and truncate any large pages in place so as to avoid a case in the second step where an incoming entry for a large page at a lower address overlaps with a replacement entry chosen at another index. Then preinitialize the TLB using addresses outside our usual unique range and avoiding clashes with any entries received, before making the usual call to local_flush_tlb_all(). This fixes (at least) R4x00 cores if TLBP hits multiple matching TLB entries (SGI IP22 PROM for examples sets up all TLBs to the same virtual address). Signed-off-by: Maciej W. Rozycki Fixes: 35ad7e181541 ("MIPS: mm: tlb-r4k: Uniquify TLB entries on init") Cc: stable@vger.kernel.org Reviewed-by: Jiaxun Yang Tested-by: Jiaxun Yang # Boston I6400, M5150 sim Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

MIPS: mm: tlb-r4k: Uniquify TLB entries on init

2025-08-28T14:24:14+00:00

commit 35ad7e181541aa5757f9f316768d3e64403ec843 upstream. Hardware or bootloader will initialize TLB entries to any value, which may collide with kernel's UNIQUE_ENTRYHI value. On MIPS microAptiv/M5150 family of cores this will trigger machine check exception and cause boot failure. On M5150 simulation this could happen 7 times out of 1000 boots. Replace local_flush_tlb_all() with r4k_tlb_uniquify() which probes each TLB ENTRIHI unique value for collisions before it's written, and in case of collision try a different ASID. Cc: stable@kernel.org Signed-off-by: Jiaxun Yang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

memblock: drop memblock_free_early_nid() and memblock_free_early()

2025-03-13T11:50:07+00:00

[ Upstream commit fa27717110ae51b9b9013ced0b5143888257bb79 ] memblock_free_early_nid() is unused and memblock_free_early() is an alias for memblock_free(). Replace calls to memblock_free_early() with calls to memblock_free() and remove memblock_free_early() and memblock_free_early_nid(). Link: https://lkml.kernel.org/r/20210930185031.18648-4-rppt@kernel.org Signed-off-by: Mike Rapoport Cc: Christophe Leroy Cc: Juergen Gross Cc: Shahab Vahedi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Stable-dep-of: 29091a52562b ("of: reserved-memory: Do not make kmemleak ignore freed address") Signed-off-by: Sasha Levin

mips: Fix max_mapnr being uninitialized on early stages

2024-02-23T07:54:24+00:00

commit e1a9ae45736989c972a8d1c151bc390678ae6205 upstream. max_mapnr variable is utilized in the pfn_valid() method in order to determine the upper PFN space boundary. Having it uninitialized effectively makes any PFN passed to that method invalid. That in its turn causes the kernel mm-subsystem occasion malfunctions even after the max_mapnr variable is actually properly updated. For instance, pfn_valid() is called in the init_unavailable_range() method in the framework of the calls-chain on MIPS: setup_arch() +-> paging_init() +-> free_area_init() +-> memmap_init() +-> memmap_init_zone_range() +-> init_unavailable_range() Since pfn_valid() always returns "false" value before max_mapnr is initialized in the mem_init() method, any flatmem page-holes will be left in the poisoned/uninitialized state including the IO-memory pages. Thus any further attempts to map/remap the IO-memory by using MMU may fail. In particular it happened in my case on attempt to map the SRAM region. The kernel bootup procedure just crashed on the unhandled unaligned access bug raised in the __update_cache() method: > Unhandled kernel unaligned access[#1]: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.7.0-rc1-XXX-dirty #2056 > ... > Call Trace: > [<8011ef9c>] __update_cache+0x88/0x1bc > [<80385944>] ioremap_page_range+0x110/0x2a4 > [<80126948>] ioremap_prot+0x17c/0x1f4 > [<80711b80>] __devm_ioremap+0x8c/0x120 > [<80711e0c>] __devm_ioremap_resource+0xf4/0x218 > [<808bf244>] sram_probe+0x4f4/0x930 > [<80889d20>] platform_probe+0x68/0xec > ... Let's fix the problem by initializing the max_mapnr variable as soon as the required data is available. In particular it can be done right in the paging_init() method before free_area_init() is called since all the PFN zone boundaries have already been calculated by that time. Cc: stable@vger.kernel.org Signed-off-by: Serge Semin Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

MIPS: tlbex: Explicitly compare _PAGE_NO_EXEC against 0

2022-08-25T09:40:46+00:00

[ Upstream commit 74de14fe05dd6b151d73cb0c73c8ec874cbdcde6 ] When CONFIG_XPA is enabled, Clang warns: arch/mips/mm/tlbex.c:629:24: error: converting the result of '<<' to a boolean; did you mean '(1 << _PAGE_NO_EXEC_SHIFT) != 0'? [-Werror,-Wint-in-bool-context] if (cpu_has_rixi && !!_PAGE_NO_EXEC) { ^ arch/mips/include/asm/pgtable-bits.h:174:28: note: expanded from macro '_PAGE_NO_EXEC' # define _PAGE_NO_EXEC (1 << _PAGE_NO_EXEC_SHIFT) ^ arch/mips/mm/tlbex.c:2568:24: error: converting the result of '<<' to a boolean; did you mean '(1 << _PAGE_NO_EXEC_SHIFT) != 0'? [-Werror,-Wint-in-bool-context] if (!cpu_has_rixi || !_PAGE_NO_EXEC) { ^ arch/mips/include/asm/pgtable-bits.h:174:28: note: expanded from macro '_PAGE_NO_EXEC' # define _PAGE_NO_EXEC (1 << _PAGE_NO_EXEC_SHIFT) ^ 2 errors generated. _PAGE_NO_EXEC can be '0' or '1 << _PAGE_NO_EXEC_SHIFT' depending on the build and runtime configuration, which is what the negation operators are trying to convey. To silence the warning, explicitly compare against 0 so the result of the '<<' operator is not implicitly converted to a boolean. According to its documentation, GCC enables -Wint-in-bool-context with -Wall but this warning is not visible when building the same configuration with GCC. It appears GCC only warns when compiling C++, not C, although the documentation makes no note of this: https://godbolt.org/z/x39q3brxf Reported-by: Sudip Mukherjee (Codethink) Signed-off-by: Nathan Chancellor Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Fixed __debug_virt_addr_valid()

2022-08-17T12:24:08+00:00

[ Upstream commit 8a2b456665d1e797123669581524cbb095fb003b ] It is permissible for kernel code to call virt_to_phys() against virtual addresses that are in KSEG0 or KSEG1 and we need to be dealing with both types. Rewrite the test condition to ensure that the kernel virtual addresses are above PAGE_OFFSET which they must be, and below KSEG2 where the non-linear mapping starts. For EVA, there is not much that we can do given the linear address range that is offered, so just return any virtual address as being valid. Finally, when HIGHMEM is not enabled, all virtual addresses are assumed to be valid as well. Fixes: dfad83cb7193 ("MIPS: Add support for CONFIG_DEBUG_VIRTUAL") Signed-off-by: Florian Fainelli Reviewed-by: Serge Semin Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Sanitise Cavium switch cases in TLB handler synthesizers

2022-04-08T12:23:38+00:00

[ Upstream commit 6ddcba9d480b6bcced4223a729794dfa6becb7eb ] It makes no sense to fall through to `break'. Therefore reorder the switch statements so as to have the Cavium cases first, followed by the default case, which improves readability and pacifies code analysis tools. No change in semantics, assembly produced is exactly the same. Reported-by: kernel test robot Signed-off-by: Maciej W. Rozycki Fixes: bc431d2153cc ("MIPS: Fix fall-through warnings for Clang") Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

Merge tag 'mips_5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

2021-09-03T18:11:54+00:00

Pull MIPS updates from Thomas Bogendoerfer: - converted Pistachio platform to use MIPS generic kernel - fixes and cleanups * tag 'mips_5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (29 commits) MIPS: Malta: fix alignment of the devicetree buffer MIPS: ingenic: Unconditionally enable clock of CPU #0 MIPS: mscc: ocelot: mark the phy-mode for internal PHY ports MIPS: mscc: ocelot: disable all switch ports by default MAINTAINERS: adjust PISTACHIO SOC SUPPORT after its retirement MIPS: Return true/false (not 1/0) from bool functions MIPS: generic: Return true/false (not 1/0) from bool functions MIPS: Make a alias for pistachio_defconfig MIPS: Retire MACH_PISTACHIO MIPS: config: generic: Add config for Marduk board pinctrl: pistachio: Make it as an option phy: pistachio-usb: Depend on MIPS || COMPILE_TEST clocksource/drivers/pistachio: Make it selectable for MIPS clk: pistachio: Make it selectable for generic MIPS kernel MIPS: DTS: Pistachio add missing cpc and cdmm MIPS: generic: Allow generating FIT image for Marduk board MIPS: locking/atomic: Fix atomic{_64,}_sub_if_positive MIPS: loongson2ef: don't build serial.o unconditionally MIPS: Replace deprecated CPU-hotplug functions. MIPS: Alchemy: Fix spelling contraction "cant" -> "can't" ...

mips: clean up kernel-doc in mm/c-octeon.c

2021-07-28T09:22:21+00:00

Clean up kernel-doc warnings in arch/mips/mm/c-octeon.c. arch/mips/mm/c-octeon.c:34: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Octeon automatically flushes the dcache on tlb changes, so arch/mips/mm/c-octeon.c:65: warning: expecting prototype for Flush caches as necessary for all cores affected by a(). Prototype was for octeon_flush_icache_all_cores() instead arch/mips/mm/c-octeon.c:99: warning: expecting prototype for Called to flush the icache on all cores(). Prototype was for octeon_flush_icache_all() instead arch/mips/mm/c-octeon.c:111: warning: expecting prototype for Called to flush all memory associated with a memory(). Prototype was for octeon_flush_cache_mm() instead arch/mips/mm/c-octeon.c:124: warning: Function parameter or member 'start' not described in 'octeon_flush_icache_range' arch/mips/mm/c-octeon.c:124: warning: Function parameter or member 'end' not described in 'octeon_flush_icache_range' arch/mips/mm/c-octeon.c:124: warning: expecting prototype for Flush a range of kernel addresses out of the icache(). Prototype was for octeon_flush_icache_range() instead arch/mips/mm/c-octeon.c:138: warning: expecting prototype for Flush a range out of a vma(). Prototype was for octeon_flush_cache_range() instead arch/mips/mm/c-octeon.c:153: warning: expecting prototype for Flush a specific page of a vma(). Prototype was for octeon_flush_cache_page() instead arch/mips/mm/c-octeon.c:164: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Probe Octeon's caches arch/mips/mm/c-octeon.c:264: warning: expecting prototype for Setup the Octeon cache flush routines(). Prototype was for octeon_cache_init() instead arch/mips/mm/c-octeon.c:349: warning: expecting prototype for Called when the the exception is not recoverable(). Prototype was for cache_parity_error_octeon_non_recoverable() instead Signed-off-by: Randy Dunlap Reported-by: kernel test robot Cc: Aditya Srivastava Cc: Thomas Bogendoerfer Cc: linux-mips@vger.kernel.org Signed-off-by: Thomas Bogendoerfer

MIPS: Fix fall-through warnings for Clang

2021-07-13T20:00:23+00:00

Fix the following fallthrough warnings: arch/mips/mm/tlbex.c:1386:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough] arch/mips/mm/tlbex.c:2173:3: error: unannotated fall-through between switch labels [-Werror,-Wimplicit-fallthrough] Reported-by: kernel test robot Link: https://lore.kernel.org/lkml/60edca25.k00ut905IFBjPyt5%25lkp@intel.com/ Signed-off-by: Gustavo A. R. Silva