From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 804063C456F for ; Fri, 28 Aug 2026 05:40:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787895648; cv=none; b=op0QbLkKf6ikPzbsGyPBETmgnS6PLJ8bQHXzAo2TH9x1urOCJKV2kn+GP0xLlHNaJBzBJ/uTwQvMRcBlnFRtlJKGnOgQWCsNMET3XkQhyQH5rfb+fRhOmDT3MmZl5HtkdF/ZLRO7KGQg6nF+8Mcq/fgGJsitKLmX4a2ipK7iPC4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787895648; c=relaxed/simple; bh=cibjQw1bVA9TKi2A8/zVZX8xPHoFrK1eB8BXJkUit4Q=; h=Date:To:From:Subject:Message-Id; b=R85egneUDFlj8kNYQT0b6zzwDOo59ivirCb6TcS4SfbZ0DMpYYwu9sfR+aeBpBiooUuTfxGbrJLn8LyirB32icsCzv9Zs/odbEBG4Xsgi2jlqiBi26J/OqIHfm7w6b3sc7n/mzgaoUuHZk8mzePhQ/MQew+dt5uQSSQXKGQ1BYU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=Mk+AJYh9; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="Mk+AJYh9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1BD591F00A3D; Fri, 28 Aug 2026 05:40:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1787895646; bh=S5qMAXVLkgylR80cJfRWl7ODKui5AoVS489bgRPgcBs=; h=Date:To:From:Subject; b=Mk+AJYh9Bz5hN6DSNFsGUeecVXuM6r1yJaRkEJGTcUx0KUeEIoT5vR8jyqNdY1FGq s23IaHjDiHl5uFJJLEdoRRm3S5eYUY36DGlzEYLRUctrfHTLhn/pHKrx8yHph3Iu/p o9AVd4+C7EHMZNNuu4IVVcob+KK2BWoRbGYnza7w= Date: Thu, 27 Aug 2026 22:40:45 -0700 To: mm-commits@vger.kernel.org,rppt@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-execmem-use-vm_flush_reset_perms-for-rox-cache-allocations.patch added to mm-new branch Message-Id: <20260828054046.1BD591F00A3D@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/execmem: use VM_FLUSH_RESET_PERMS for ROX cache allocations has been added to the -mm mm-new branch. Its filename is mm-execmem-use-vm_flush_reset_perms-for-rox-cache-allocations.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-execmem-use-vm_flush_reset_perms-for-rox-cache-allocations.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: "Mike Rapoport (Microsoft)" Subject: mm/execmem: use VM_FLUSH_RESET_PERMS for ROX cache allocations Date: Sun, 23 Aug 2026 14:46:16 +0300 Initially execmem completely removed direct map alias for the memory allocated for the ROX cache in PMD_SIZE chunks. When that memory was freed, its direct map was restored also in PMD_SIZE chunks to avoid fragmentation of the direct map caused by vmalloc::vm_reset_perms(). This required execmem to implement the wrappers for set_direct_map APIs for proper sequencing of removal and restoration of the direct map aliases. Since then x86's CPA gained support for collapsing the direct map page tables for ROX pages and execmem switched from removing ROX caches from the direct map to making them ROX there, so execmem only needs to update direct map alias permissions when freeing the ROX cache memory. vmalloc already handles those updates for areas with VM_FLUSH_RESET_PERMS set and vmalloc::vm_reset_perms() does not force split of the direct map for PMD_SIZE chunks. Make all execmem vmalloc allocations use VM_FLUSH_RESET_PERMS and remove custom wrappers for set_direct_map APIs. Link: https://lore.kernel.org/20260823-execmem-set-vm-perms-v0-2-v2-5-b013a37d84b3@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andy Lutomirski Cc: "Borislav Petkov (AMD)" Cc: Brendan Jackman Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Dave Hansen Cc: David Hildenbrand Cc: Gerald Schaefer Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Len Brown Cc: Palmer Dabbelt Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Ryan Roberts Cc: Sven Schnelle Cc: "Uladzislau Rezki (Sony)" Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/execmem.c | 42 +++++++----------------------------------- 1 file changed, 7 insertions(+), 35 deletions(-) --- a/mm/execmem.c~mm-execmem-use-vm_flush_reset_perms-for-rox-cache-allocations +++ a/mm/execmem.c @@ -36,6 +36,7 @@ static void *execmem_vmalloc(struct exec unsigned long end = range->end; void *p; + vm_flags |= VM_FLUSH_RESET_PERMS; if (kasan) vm_flags |= VM_DEFER_KMEMLEAK; @@ -113,28 +114,6 @@ static inline unsigned long mas_range_le return mas->last - mas->index + 1; } -static int execmem_set_direct_map_valid(struct vm_struct *vm, bool valid) -{ - unsigned int nr = (1 << get_vm_area_page_order(vm)); - unsigned int updated = 0; - int err = 0; - - for (int i = 0; i < vm->nr_pages; i += nr) { - err = set_direct_map_valid_noflush(vm->pages[i], nr, valid); - if (err) - goto err_restore; - updated += nr; - } - - return 0; - -err_restore: - for (int i = 0; i < updated; i += nr) - set_direct_map_valid_noflush(vm->pages[i], nr, !valid); - - return err; -} - static int execmem_force_rw(void *ptr, size_t size) { unsigned int nr = PAGE_ALIGN(size) >> PAGE_SHIFT; @@ -169,9 +148,6 @@ static void execmem_cache_clean(struct w if (IS_ALIGNED(size, PMD_SIZE) && IS_ALIGNED(mas.index, PMD_SIZE)) { - struct vm_struct *vm = find_vm_area(area); - - execmem_set_direct_map_valid(vm, true); mas_store_gfp(&mas, NULL, GFP_KERNEL); vfree(area); } @@ -312,18 +288,15 @@ static void *execmem_cache_populate_allo */ mutex_lock(mutex); err = execmem_cache_add_locked(p, alloc_size, GFP_KERNEL); - if (err) - goto err_reset_direct_map; - - p = execmem_cache_alloc_locked(range, size); - + if (!err) + p = execmem_cache_alloc_locked(range, size); mutex_unlock(mutex); + if (err) + goto err_free_mem; + return p; -err_reset_direct_map: - mutex_unlock(mutex); - execmem_set_direct_map_valid(vm, true); err_free_mem: vfree(p); return NULL; @@ -466,7 +439,6 @@ void *execmem_alloc(enum execmem_type ty { struct execmem_range *range = &execmem_info->ranges[type]; bool use_cache = range->flags & EXECMEM_ROX_CACHE; - unsigned long vm_flags = VM_FLUSH_RESET_PERMS; pgprot_t pgprot = range->pgprot; void *p = NULL; @@ -475,7 +447,7 @@ void *execmem_alloc(enum execmem_type ty if (use_cache) p = execmem_cache_alloc(range, size); else - p = execmem_vmalloc(range, size, pgprot, vm_flags); + p = execmem_vmalloc(range, size, pgprot, 0); return kasan_reset_tag(p); } _ Patches currently in -mm which might be from rppt@kernel.org are set_memory-add-number-of-pages-parameter-to-set_direct_map-apis.patch mm-vmalloc-set-areas-page_order-after-allocation-succeeds.patch mm-vmalloc-constify-vm-parameter-of-get_vm_area_page_order.patch mm-vmalloc-make-set_area_direct_map-huge_vmap-friendly.patch mm-execmem-use-vm_flush_reset_perms-for-rox-cache-allocations.patch revert-arch-introduce-set_direct_map_valid_noflush.patch sh-remove-config_numa-and-realted-configuration-options.patch sh-mm-remove-numac.patch sh-mm-drop-allocate_pgdat.patch sh-remove-setup_bootmem_node-and-plat_mem_setup.patch sh-drop-dead-code-guarded-by-ifdef-config_numa.patch sh-drop-include-asm-mmzoneh.patch init-kconfig-drop-arch_want_numa_variable_locality.patch sh-init-remove-call-the-memblock_set_node.patch sh-remove-sparsemem-related-entries-from-kconfig.patch sh-drop-include-asm-sparsememh.patch