From bd40b053fabe27209cb240d205a0c817cbe5fb87 Mon Sep 17 00:00:00 2001 From: Oscar Salvador Date: Mon, 7 Oct 2024 09:50:37 +0200 Subject: mm: consolidate common checks in hugetlb_get_unmapped_area prepare_hugepage_range() performs almost the same checks for all architectures that define it, with the exception of mips and loongarch that also check for overflows. The rest checks for the addr and len to be properly aligned, so we can move that to hugetlb_get_unmapped_area() and get rid of a fair amount of duplicated code. [akpm@linux-foundation.org: remove now-unused local] Link: https://lore.kernel.org/oe-kbuild-all/202410081210.uNLbf3Jk-lkp@intel.com/ Link: https://lkml.kernel.org/r/20241007075037.267650-10-osalvador@suse.de Signed-off-by: Oscar Salvador Cc: David Hildenbrand Cc: Donet Tom Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Muchun Song Cc: Peter Xu Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- arch/mips/include/asm/hugetlb.h | 5 ----- 1 file changed, 5 deletions(-) (limited to 'arch/mips') diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h index fd69c8808554..d0a86ce83de9 100644 --- a/arch/mips/include/asm/hugetlb.h +++ b/arch/mips/include/asm/hugetlb.h @@ -17,12 +17,7 @@ static inline int prepare_hugepage_range(struct file *file, unsigned long len) { unsigned long task_size = STACK_TOP; - struct hstate *h = hstate_file(file); - if (len & ~huge_page_mask(h)) - return -EINVAL; - if (addr & ~huge_page_mask(h)) - return -EINVAL; if (len > task_size) return -ENOMEM; if (task_size - len < addr) -- cgit v1.2.3 From 0c3beacf681ec897e0b36685a9b49d01f5cb2dfb Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (Microsoft)" Date: Wed, 23 Oct 2024 19:27:06 +0300 Subject: asm-generic: introduce text-patching.h Several architectures support text patching, but they name the header files that declare patching functions differently. Make all such headers consistently named text-patching.h and add an empty header in asm-generic for architectures that do not support text patching. Link: https://lkml.kernel.org/r/20241023162711.2579610-4-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Reviewed-by: Christoph Hellwig Acked-by: Geert Uytterhoeven # m68k Acked-by: Arnd Bergmann Reviewed-by: Luis Chamberlain Tested-by: kdevops Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Borislav Petkov (AMD) Cc: Brian Cain Cc: Catalin Marinas Cc: Christophe Leroy Cc: Dave Hansen Cc: Dinh Nguyen Cc: Guo Ren Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Kent Overstreet Cc: Liam R. Howlett Cc: Mark Rutland Cc: Masami Hiramatsu (Google) Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Oleg Nesterov Cc: Palmer Dabbelt Cc: Peter Zijlstra Cc: Richard Weinberger Cc: Russell King Cc: Song Liu Cc: Stafford Horne Cc: Steven Rostedt (Google) Cc: Suren Baghdasaryan Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Uladzislau Rezki (Sony) Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/mips/include/asm/Kbuild | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/mips') diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild index 7ba67a0d6c97..684569b2ecd6 100644 --- a/arch/mips/include/asm/Kbuild +++ b/arch/mips/include/asm/Kbuild @@ -13,3 +13,4 @@ generic-y += parport.h generic-y += qrwlock.h generic-y += qspinlock.h generic-y += user.h +generic-y += text-patching.h -- cgit v1.2.3 From 662df3e5c37666d6ed75c88098699e070a4b35b5 Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Mon, 28 Oct 2024 14:13:29 +0000 Subject: mm: madvise: implement lightweight guard page mechanism Implement a new lightweight guard page feature, that is regions of userland virtual memory that, when accessed, cause a fatal signal to arise. Currently users must establish PROT_NONE ranges to achieve this. However this is very costly memory-wise - we need a VMA for each and every one of these regions AND they become unmergeable with surrounding VMAs. In addition repeated mmap() calls require repeated kernel context switches and contention of the mmap lock to install these ranges, potentially also having to unmap memory if installed over existing ranges. The lightweight guard approach eliminates the VMA cost altogether - rather than establishing a PROT_NONE VMA, it operates at the level of page table entries - establishing PTE markers such that accesses to them cause a fault followed by a SIGSGEV signal being raised. This is achieved through the PTE marker mechanism, which we have already extended to provide PTE_MARKER_GUARD, which we installed via the generic page walking logic which we have extended for this purpose. These guard ranges are established with MADV_GUARD_INSTALL. If the range in which they are installed contain any existing mappings, they will be zapped, i.e. free the range and unmap memory (thus mimicking the behaviour of MADV_DONTNEED in this respect). Any existing guard entries will be left untouched. There is therefore no nesting of guarded pages. Guarded ranges are NOT cleared by MADV_DONTNEED nor MADV_FREE (in both instances the memory range may be reused at which point a user would expect guards to still be in place), but they are cleared via MADV_GUARD_REMOVE, process teardown or unmapping of memory ranges. The guard property can be removed from ranges via MADV_GUARD_REMOVE. The ranges over which this is applied, should they contain non-guard entries, will be untouched, with only guard entries being cleared. We permit this operation on anonymous memory only, and only VMAs which are non-special, non-huge and not mlock()'d (if we permitted this we'd have to drop locked pages which would be rather counterintuitive). Racing page faults can cause repeated attempts to install guard pages that are interrupted, result in a zap, and this process can end up being repeated. If this happens more than would be expected in normal operation, we rescind locks and retry the whole thing, which avoids lock contention in this scenario. Link: https://lkml.kernel.org/r/6aafb5821bf209f277dfae0787abb2ef87a37542.1730123433.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Suggested-by: Vlastimil Babka Suggested-by: Jann Horn Suggested-by: David Hildenbrand Suggested-by: Vlastimil Babka Suggested-by: Jann Horn Suggested-by: David Hildenbrand Acked-by: Vlastimil Babka Cc: Arnd Bergmann Cc: Christian Brauner Cc: Christoph Hellwig Cc: Chris Zankel Cc: Helge Deller Cc: James E.J. Bottomley Cc: Jeff Xu Cc: John Hubbard Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Matt Turner Cc: Max Filippov Cc: Muchun Song Cc: Paul E. McKenney Cc: Richard Henderson Cc: Shuah Khan Cc: Shuah Khan Cc: Sidhartha Kumar Cc: Suren Baghdasaryan Cc: Thomas Bogendoerfer Signed-off-by: Andrew Morton --- arch/mips/include/uapi/asm/mman.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/mips') diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h index 9c48d9a21aa0..b700dae28c48 100644 --- a/arch/mips/include/uapi/asm/mman.h +++ b/arch/mips/include/uapi/asm/mman.h @@ -105,6 +105,9 @@ #define MADV_COLLAPSE 25 /* Synchronous hugepage collapse */ +#define MADV_GUARD_INSTALL 102 /* fatal signal on access to range */ +#define MADV_GUARD_REMOVE 103 /* unguard range */ + /* compatibility flags */ #define MAP_FILE 0 -- cgit v1.2.3 From 7269ed4af344184ab9bdf318fe8864cf64849735 Mon Sep 17 00:00:00 2001 From: Bibo Mao Date: Mon, 4 Nov 2024 15:07:12 +0800 Subject: mm: define general function pXd_init() pud_init(), pmd_init() and kernel_pte_init() are duplicated defined in file kasan.c and sparse-vmemmap.c as weak functions. Move them to generic header file pgtable.h, architecture can redefine them. Link: https://lkml.kernel.org/r/20241104070712.52902-1-maobibo@loongson.cn Signed-off-by: Bibo Mao Reviewed-by: Huacai Chen Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Thomas Bogendoerfer Cc: Vincenzo Frascino Cc: WANG Xuerui Signed-off-by: Andrew Morton --- arch/mips/include/asm/pgtable-64.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/mips') diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h index 401c1d9e4409..6e854bb11f37 100644 --- a/arch/mips/include/asm/pgtable-64.h +++ b/arch/mips/include/asm/pgtable-64.h @@ -317,7 +317,9 @@ static inline pmd_t *pud_pgtable(pud_t pud) */ extern void pgd_init(void *addr); extern void pud_init(void *addr); +#define pud_init pud_init extern void pmd_init(void *addr); +#define pmd_init pmd_init /* * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that -- cgit v1.2.3