The quilt patch titled Subject: alloc_tag: avoid execmem_vmap() when !MMU has been removed from the -mm tree. Its filename was alloc_tag-populate-memory-for-module-tags-as-needed-fix.patch This patch was dropped because an updated version will be issued ------------------------------------------------------ From: Suren Baghdasaryan <surenb@xxxxxxxxxx> Subject: alloc_tag: avoid execmem_vmap() when !MMU Date: Mon, 28 Oct 2024 13:29:35 -0700 With CONFIG_MMU=n __get_vm_area_node() is not available and memory for the allocation tags cannot be populated as needed. For this case, populate the required memory at initialization time. Link: https://lkml.kernel.org/r/20241028202935.1047017-1-surenb@xxxxxxxxxx Fixes: 57bc3834fb6f ("alloc_tag: populate memory for module tags as needed") Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> Closes: https://lore.kernel.org/oe-kbuild-all/202410250808.dQGyYjlk-lkp@xxxxxxxxx/ Closes: https://lore.kernel.org/oe-lkp/202410251525.9f85854d-oliver.sang@xxxxxxxxx Closes: https://lore.kernel.org/oe-kbuild-all/202410261016.IO7C6Cml-lkp@xxxxxxxxx/ Closes: https://lore.kernel.org/oe-kbuild-all/202410270919.LebQlmxD-lkp@xxxxxxxxx/ Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx> Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Cc: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Song Liu <song@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/execmem.h | 2 ++ lib/alloc_tag.c | 23 ++++++++++++++++++++++- mm/execmem.c | 32 ++++++++++++++++---------------- 3 files changed, 40 insertions(+), 17 deletions(-) --- a/include/linux/execmem.h~alloc_tag-populate-memory-for-module-tags-as-needed-fix +++ a/include/linux/execmem.h @@ -139,6 +139,7 @@ void *execmem_alloc(enum execmem_type ty */ void execmem_free(void *ptr); +#ifdef CONFIG_MMU /** * execmem_vmap - create virtual mapping for EXECMEM_MODULE_DATA memory * @size: size of the virtual mapping in bytes @@ -148,6 +149,7 @@ void execmem_free(void *ptr); * Return: the area descriptor on success or %NULL on failure. */ struct vm_struct *execmem_vmap(size_t size); +#endif /** * execmem_update_copy - copy an update to executable memory --- a/lib/alloc_tag.c~alloc_tag-populate-memory-for-module-tags-as-needed-fix +++ a/lib/alloc_tag.c @@ -180,7 +180,6 @@ static void __init procfs_init(void) #ifdef CONFIG_MODULES static struct maple_tree mod_area_mt = MTREE_INIT(mod_area_mt, MT_FLAGS_ALLOC_RANGE); -static struct vm_struct *vm_module_tags; /* A dummy object used to indicate an unloaded module */ static struct module unloaded_mod; /* A dummy object used to indicate a module prepended area */ @@ -254,6 +253,9 @@ repeat: return false; } +#ifdef CONFIG_MMU +static struct vm_struct *vm_module_tags; + static int vm_module_tags_populate(void) { unsigned long phys_size = vm_module_tags->nr_pages << PAGE_SHIFT; @@ -280,6 +282,13 @@ static int vm_module_tags_populate(void) return 0; } +#else +static int vm_module_tags_populate(void) +{ + /* Memory was already allocated */ + return 0; +} +#endif static void *reserve_module_tags(struct module *mod, unsigned long size, unsigned int prepend, unsigned long align) @@ -411,6 +420,7 @@ static void replace_module(struct module static int __init alloc_mod_tags_mem(void) { +#ifdef CONFIG_MMU /* Map space to copy allocation tags */ vm_module_tags = execmem_vmap(MODULE_ALLOC_TAG_VMAP_SIZE); if (!vm_module_tags) { @@ -428,6 +438,13 @@ static int __init alloc_mod_tags_mem(voi } module_tags.start_addr = (unsigned long)vm_module_tags->addr; +#else + /* Allocate space to copy allocation tags */ + module_tags.start_addr = (unsigned long)execmem_alloc(EXECMEM_MODULE_DATA, + MODULE_ALLOC_TAG_VMAP_SIZE); + if (!module_tags.start_addr) + return -ENOMEM; +#endif module_tags.end_addr = module_tags.start_addr + MODULE_ALLOC_TAG_VMAP_SIZE; return 0; @@ -435,6 +452,7 @@ static int __init alloc_mod_tags_mem(voi static void __init free_mod_tags_mem(void) { +#ifdef CONFIG_MMU int i; module_tags.start_addr = 0; @@ -442,6 +460,9 @@ static void __init free_mod_tags_mem(voi __free_page(vm_module_tags->pages[i]); kfree(vm_module_tags->pages); free_vm_area(vm_module_tags); +#else + execmem_free((void *)module_tags.start_addr); +#endif } #else /* CONFIG_MODULES */ --- a/mm/execmem.c~alloc_tag-populate-memory-for-module-tags-as-needed-fix +++ a/mm/execmem.c @@ -64,6 +64,22 @@ static void *execmem_vmalloc(struct exec return p; } + +struct vm_struct *execmem_vmap(size_t size) +{ + struct execmem_range *range = &execmem_info->ranges[EXECMEM_MODULE_DATA]; + struct vm_struct *area; + + area = __get_vm_area_node(size, range->alignment, PAGE_SHIFT, VM_ALLOC, + range->start, range->end, NUMA_NO_NODE, + GFP_KERNEL, __builtin_return_address(0)); + if (!area && range->fallback_start) + area = __get_vm_area_node(size, range->alignment, PAGE_SHIFT, VM_ALLOC, + range->fallback_start, range->fallback_end, + NUMA_NO_NODE, GFP_KERNEL, __builtin_return_address(0)); + + return area; +} #else static void *execmem_vmalloc(struct execmem_range *range, size_t size, pgprot_t pgprot, unsigned long vm_flags) @@ -368,22 +384,6 @@ void execmem_free(void *ptr) vfree(ptr); } -struct vm_struct *execmem_vmap(size_t size) -{ - struct execmem_range *range = &execmem_info->ranges[EXECMEM_MODULE_DATA]; - struct vm_struct *area; - - area = __get_vm_area_node(size, range->alignment, PAGE_SHIFT, VM_ALLOC, - range->start, range->end, NUMA_NO_NODE, - GFP_KERNEL, __builtin_return_address(0)); - if (!area && range->fallback_start) - area = __get_vm_area_node(size, range->alignment, PAGE_SHIFT, VM_ALLOC, - range->fallback_start, range->fallback_end, - NUMA_NO_NODE, GFP_KERNEL, __builtin_return_address(0)); - - return area; -} - void *execmem_update_copy(void *dst, const void *src, size_t size) { return text_poke_copy(dst, src, size); _ Patches currently in -mm which might be from surenb@xxxxxxxxxx are maple_tree-add-mas_for_each_rev-helper.patch alloc_tag-introduce-shutdown_mem_profiling-helper-function.patch alloc_tag-load-module-tags-into-separate-contiguous-memory.patch alloc_tag-populate-memory-for-module-tags-as-needed.patch alloc_tag-populate-memory-for-module-tags-as-needed-fix-2.patch alloc_tag-introduce-pgtag_ref_handle-to-abstract-page-tag-references.patch alloc_tag-support-for-page-allocation-tag-compression.patch mm-convert-mm_lock_seq-to-a-proper-seqcount.patch mm-introduce-mmap_lock_speculation_beginend.patch mm-codetag-uninline-and-move-pgalloc_tag_copy-and-pgalloc_tag_split.patch