linux-dev/arch/xtensa/mm, branch linus/master

xtensa: noMMU: allow handling protection faults

2022-05-02T02:51:21Z

Many xtensa CPU cores without full MMU still have memory protection features capable of raising exceptions for invalid instruction fetches/data access. Allow handling such exceptions. This improves behavior of processes that pass invalid memory pointers to syscalls in noMMU configs: in case of exception the kernel instead of killing the process is now able to return -EINVAL from a syscall. Introduce CONFIG_PFAULT that controls whether protection fault code is enabled and register handlers for common memory protection exceptions when it is enabled. Signed-off-by: Max Filippov

xtensa: extract vmalloc_fault code into a function

2022-05-02T02:51:21Z

Move full MMU-specific code into a separate function to isolate it from more generic do_page_fault code. No functional changes. Signed-off-by: Max Filippov

xtensa: move asid_cache from fault.c to mmu.c

2022-05-02T02:51:20Z

asid_cache is only useful with full MMU, but fault.c is also useful with MPU. Move asid_cache definition to MMU-specific source file. Signed-off-by: Max Filippov

xtensa: define update_mmu_tlb function

2022-03-22T16:45:09Z

Before the commit f9ce0be71d1f ("mm: Cleanup faultaround and finish_fault() codepaths") there was a call to update_mmu_cache in alloc_set_pte that used to invalidate TLB entry caching invalid PTE that caused a page fault. That commit removed that call so now invalid TLB entry survives causing repetitive page faults on the CPU that took the initial fault until that TLB entry is occasionally evicted. This issue is spotted by the xtensa TLB sanity checker. Fix this issue by defining update_mmu_tlb function that flushes TLB entry for the faulting address. Cc: stable@vger.kernel.org # 5.12+ Signed-off-by: Max Filippov

mm: remove redundant check about FAULT_FLAG_ALLOW_RETRY bit

2022-01-15T14:30:27Z

Since commit 4064b9827063 ("mm: allow VM_FAULT_RETRY for multiple times") allowed VM_FAULT_RETRY for multiple times, the FAULT_FLAG_ALLOW_RETRY bit of fault_flag will not be changed in the page fault path, so the following check is no longer needed: flags & FAULT_FLAG_ALLOW_RETRY So just remove it. [akpm@linux-foundation.org: coding style fixes] Link: https://lkml.kernel.org/r/20211110123358.36511-1-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Cc: Peter Zijlstra Cc: Ingo Molnar Cc: David Hildenbrand Cc: Kirill Shutemov Cc: Peter Xu Cc: Muchun Song Cc: Chengming Zhou Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2021-11-11T00:15:54Z

Pull exit cleanups from Eric Biederman: "While looking at some issues related to the exit path in the kernel I found several instances where the code is not using the existing abstractions properly. This set of changes introduces force_fatal_sig a way of sending a signal and not allowing it to be caught, and corrects the misuse of the existing abstractions that I found. A lot of the misuse of the existing abstractions are silly things such as doing something after calling a no return function, rolling BUG by hand, doing more work than necessary to terminate a kernel thread, or calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL). In the review a deficiency in force_fatal_sig and force_sig_seccomp where ptrace or sigaction could prevent the delivery of the signal was found. I have added a change that adds SA_IMMUTABLE to change that makes it impossible to interrupt the delivery of those signals, and allows backporting to fix force_sig_seccomp And Arnd found an issue where a function passed to kthread_run had the wrong prototype, and after my cleanup was failing to build." * 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits) soc: ti: fix wkup_m3_rproc_boot_thread return type signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) exit/r8188eu: Replace the macro thread_exit with a simple return 0 exit/rtl8712: Replace the macro thread_exit with a simple return 0 exit/rtl8723bs: Replace the macro thread_exit with a simple return 0 signal/x86: In emulate_vsyscall force a signal instead of calling do_exit signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails exit/syscall_user_dispatch: Send ordinary signals on failure signal: Implement force_fatal_sig exit/kthread: Have kernel threads return instead of calling do_exit signal/s390: Use force_sigsegv in default_trap_handler signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved. signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON signal/sparc: In setup_tsb_params convert open coded BUG into BUG signal/powerpc: On swapcontext failure force SIGSEGV signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL) signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT signal/sparc32: Remove unreachable do_exit in do_sparc_fault ...

exit: Remove calls of do_exit after noreturn versions of die

2021-10-20T18:09:47Z

On nds32, openrisc, s390, sh, and xtensa the function die never returns. Mark die __noreturn so that no one expects die to return. Remove the do_exit calls after die as they will never be reached. Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: Stafford Horne Cc: openrisc@lists.librecores.org Cc: Nick Hu Cc: Greentime Hu Cc: Vincent Chen Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: linux-s390@vger.kernel.org Cc: Yoshinori Sato Cc: Rich Felker Cc: linux-sh@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: Chris Zankel Cc: Max Filippov Fixes: 2.3.16 Fixes: 2.3.99-pre8 Fixes: 3f65ce4d141e ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 5") Fixes: 664eec400bf8 ("nds32: MMU fault handling and page table management") Fixes: 61e85e367535 ("OpenRISC: Memory management") Link: https://lkml.kernel.org/r/20211020174406.17889-2-ebiederm@xmission.com Signed-off-by: Eric W. Biederman

xtensa: use CONFIG_USE_OF instead of CONFIG_OF

2021-09-27T13:08:58Z

CONFIG_OF can be set by a randconfig or by a user -- without setting the early flattree option (OF_EARLY_FLATTREE). This causes build errors. However, if randconfig or a user sets USE_OF in the Xtensa config, the right kconfig symbols are set to fix the build. Fixes these build errors: ../arch/xtensa/kernel/setup.c:67:19: error: ‘__dtb_start’ undeclared here (not in a function); did you mean ‘dtb_start’? 67 | void *dtb_start = __dtb_start; | ^~~~~~~~~~~ ../arch/xtensa/kernel/setup.c: In function 'xtensa_dt_io_area': ../arch/xtensa/kernel/setup.c:201:14: error: implicit declaration of function 'of_flat_dt_is_compatible'; did you mean 'of_machine_is_compatible'? [-Werror=implicit-function-declaration] 201 | if (!of_flat_dt_is_compatible(node, "simple-bus")) ../arch/xtensa/kernel/setup.c:204:18: error: implicit declaration of function 'of_get_flat_dt_prop' [-Werror=implicit-function-declaration] 204 | ranges = of_get_flat_dt_prop(node, "ranges", &len); ../arch/xtensa/kernel/setup.c:204:16: error: assignment to 'const __be32 *' {aka 'const unsigned int *'} from 'int' makes pointer from integer without a cast [-Werror=int-conversion] 204 | ranges = of_get_flat_dt_prop(node, "ranges", &len); | ^ ../arch/xtensa/kernel/setup.c: In function 'early_init_devtree': ../arch/xtensa/kernel/setup.c:228:9: error: implicit declaration of function 'early_init_dt_scan'; did you mean 'early_init_devtree'? [-Werror=implicit-function-declaration] 228 | early_init_dt_scan(params); ../arch/xtensa/kernel/setup.c:229:9: error: implicit declaration of function 'of_scan_flat_dt' [-Werror=implicit-function-declaration] 229 | of_scan_flat_dt(xtensa_dt_io_area, NULL); xtensa-elf-ld: arch/xtensa/mm/mmu.o:(.text+0x0): undefined reference to `xtensa_kio_paddr' Fixes: da844a81779e ("xtensa: add device trees support") Fixes: 6cb971114f63 ("xtensa: remap io area defined in device tree") Signed-off-by: Randy Dunlap Signed-off-by: Max Filippov

Merge branch 'akpm' (patches from Andrew)

2021-04-30T21:38:01Z

Merge misc updates from Andrew Morton: "A few misc subsystems and some of MM. 175 patches. Subsystems affected by this patch series: ia64, kbuild, scripts, sh, ocfs2, kfifo, vfs, kernel/watchdog, and mm (slab-generic, slub, kmemleak, debug, pagecache, msync, gup, memremap, memcg, pagemap, mremap, dma, sparsemem, vmalloc, documentation, kasan, initialization, pagealloc, and memory-failure)" * emailed patches from Andrew Morton : (175 commits) mm/memory-failure: unnecessary amount of unmapping mm/mmzone.h: fix existing kernel-doc comments and link them to core-api mm: page_alloc: ignore init_on_free=1 for debug_pagealloc=1 net: page_pool: use alloc_pages_bulk in refill code path net: page_pool: refactor dma_map into own function page_pool_dma_map SUNRPC: refresh rq_pages using a bulk page allocator SUNRPC: set rq_page_end differently mm/page_alloc: inline __rmqueue_pcplist mm/page_alloc: optimize code layout for __alloc_pages_bulk mm/page_alloc: add an array-based interface to the bulk page allocator mm/page_alloc: add a bulk page allocator mm/page_alloc: rename alloced to allocated mm/page_alloc: duplicate include linux/vmalloc.h mm, page_alloc: avoid page_to_pfn() in move_freepages() mm/Kconfig: remove default DISCONTIGMEM_MANUAL mm: page_alloc: dump migrate-failed pages mm/mempolicy: fix mpol_misplaced kernel-doc mm/mempolicy: rewrite alloc_pages_vma documentation mm/mempolicy: rewrite alloc_pages documentation mm/mempolicy: rename alloc_pages_current to alloc_pages ...

mm: move mem_init_print_info() into mm_init()

2021-04-30T18:20:42Z

mem_init_print_info() is called in mem_init() on each architecture, and pass NULL argument, so using void argument and move it into mm_init(). Link: https://lkml.kernel.org/r/20210317015210.33641-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Dave Hansen [x86] Reviewed-by: Christophe Leroy [powerpc] Acked-by: David Hildenbrand Tested-by: Anatoly Pugachev [sparc64] Acked-by: Russell King [arm] Acked-by: Mike Rapoport Cc: Catalin Marinas Cc: Richard Henderson Cc: Guo Ren Cc: Yoshinori Sato Cc: Huacai Chen Cc: Jonas Bonn Cc: Palmer Dabbelt Cc: Heiko Carstens Cc: "David S. Miller" Cc: "Peter Zijlstra" Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds