From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 07786C5DF66 for ; Sun, 16 Aug 2026 11:00:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VP6xAszPN9d5Ab+tWR5O9C7cLz2aPGLpAHH/Gr7UO8o=; b=XrFE1vypaR40kEKTy8eylARJit lRSI7MrzxZ7AVsEV5yPpmH1HpC+wjREaRI75V1nTKWdSzmygtU/Is2AArmMgFdP7mOOcfmYFq9xo9 rt+UPIX9VVthmxzZxm6L3njzwN2v8xGkmTWoeiOc+3hDAWPBUzQ5AhKEXhHuTnyc8ALg2SDdRipjI CUHxNM5/w6mskX4w8aLWAqMcqU8+c+MdOAo9JSONSVTBjfBUR4tfMpKvDcS23VGC9UHFD1B0n4t7X abcsrA1iFP52wxbUnm2mA5B5zvKQgNIgX5kFmGfhzyo3yacExeO/QdZYg/Jk5YqJoSuOQlyZ9KNW+ Kq6nUWeg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvYbL-00000004g0D-1SaP; Sun, 16 Aug 2026 11:00:27 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wvYbJ-00000004fyt-47EK; Sun, 16 Aug 2026 11:00:26 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 6AC8B601E9; Sun, 16 Aug 2026 11:00:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6F581F00A3A; Sun, 16 Aug 2026 11:00:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786878025; bh=VP6xAszPN9d5Ab+tWR5O9C7cLz2aPGLpAHH/Gr7UO8o=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=HFSkd1RRaS8oPDbWpyqD3+MFUAGz+zBb2E4buzBKvFx4juV0omhsnE2xW83orpu8H 9mAI5h2ZeMhHUsu1Goyi//25wRfRhy5/zldEwqXn+KNf83EMUEv8zRoPeHlgoEQi4V Oa7He8g8qJb2QsEPd1rl39eDbGrMOa8l2swjLNSuJmfqyBVg6W6hz4yFrG1D7pxBnS jwx2+tbyLbsmJcoFViUpm9otjM5Wr+gsaeyRAOH+WJPnI93lfF4TC3uGZWKpXyI+Os rTissIIc+9xMzfFeruWhWw0+3hN5L3fSFuS7lY2WLAPAG3gfVSviK2591GlnaNdjre Mmxv9eXrtRVBw== From: "Mike Rapoport (Microsoft)" Date: Sun, 16 Aug 2026 13:59:28 +0300 Subject: [PATCH 5/6] mm/execmem: use VM_FLUSH_RESET_PERMS for ROX cache allocations MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260816-execmem-set-vm-perms-v0-2-v1-5-90944a3ad43f@kernel.org> References: <20260816-execmem-set-vm-perms-v0-2-v1-0-90944a3ad43f@kernel.org> In-Reply-To: <20260816-execmem-set-vm-perms-v0-2-v1-0-90944a3ad43f@kernel.org> To: Andrew Morton Cc: =?utf-8?q?Adrian_Barna=C5=9B?= , Albert Ou , Alexander Gordeev , Alexandre Ghiti , Andy Lutomirski , Borislav Petkov , Brendan Jackman , Catalin Marinas , Christian Borntraeger , Dave Hansen , David Hildenbrand , Gerald Schaefer , Heiko Carstens , Huacai Chen , Ingo Molnar , Len Brown , Mike Rapoport , Palmer Dabbelt , Paul Walmsley , Pavel Machek , Peter Zijlstra , "H. Peter Anvin" , "Rafael J. Wysocki" , Ryan Roberts , Sven Schnelle , Thomas Gleixner , Uladzislau Rezki , Vasily Gorbik , WANG Xuerui , Will Deacon , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-pm@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, loongarch@lists.linux.dev X-Mailer: b4 0.17-dev X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. Signed-off-by: Mike Rapoport (Microsoft) --- mm/execmem.c | 42 +++++++----------------------------------- 1 file changed, 7 insertions(+), 35 deletions(-) diff --git a/mm/execmem.c b/mm/execmem.c index 74a178a87e75..d35f1d0ea54a 100644 --- a/mm/execmem.c +++ b/mm/execmem.c @@ -36,6 +36,7 @@ static void *execmem_vmalloc(struct execmem_range *range, size_t size, 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_len(struct ma_state *mas) 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 work_struct *work) 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_alloc(struct execmem_range *range, size_t si */ 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 type, size_t size) { 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 type, size_t size) 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); } -- 2.53.0