From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f53.google.com (mail-lf1-f53.google.com [209.85.167.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF47F4A33 for ; Sat, 23 Aug 2025 09:35:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755941713; cv=none; b=O0S+Ip8d+iSwpOgc7fChqZIZHFcn6RgR6wa9dWgoTU7r70ASLFMgWLCodxVfUz/YqfuUFQzmytqwxdJ9zNGRq8dxu+4fOvJg4zAySrNHe656hvnXUTFxlj/URVx6GFOkwiEw40Ff0+ZFUaI3a8xf8ltbEn74kg0zVz6uAdi2as8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755941713; c=relaxed/simple; bh=24sjhNDONNlfhjMuQocbxVfFgzhTLA154n85ceeYAig=; h=From:Date:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZlyMOVBPXq8OWpMOaI5M/ZOoDRu7MUYSlo7T9jzjQphqS6/n0S0qm2pWwR8sEvHGwVVdpYoCBNf6e6R9gpBr48P5r96lbiJtBwVMbnhfp/Dt7WditFf/8WwADko3vPCXeSIC7eTtXSDh1hxWjzviGiME64uLCWs15miPnMfb9XE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=H3UsAfUL; arc=none smtp.client-ip=209.85.167.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="H3UsAfUL" Received: by mail-lf1-f53.google.com with SMTP id 2adb3069b0e04-55f39c0a22dso525742e87.1 for ; Sat, 23 Aug 2025 02:35:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1755941710; x=1756546510; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:from:to:cc:subject:date:message-id:reply-to; bh=A92qUKVVscD1iUAIIcRKA9oYRSCgvP30+tdPO7B2xVE=; b=H3UsAfUL2POcfDoMAHyL7H3z5Q2uriOICZvRSgpQMZHS3Hr3ATaUd3JHTk/WPmMluS 3ydkCwcSx190H3cIBUSUhNaO/wvTI2Rlz0E8OaSrevXD/bersGOKzFVb0adhVL8XZO0I NsqOH18bvINMLocXgEbd4fi5E696Vj6Ghe876Ox989gOo2YH1usktFfzcY4XABJs7g0/ 7jPk2HIQWa1SjjvTlOtcwzRFtAxiWFoecZQ2vm1m4UYqbC0n5Tx6myRt2Wi9mqnVyolu 8FFxzGC7KNej5BVib43UqibhVt3g37gHCat5TE77XpFD7PhKELw5ICdrx+HLvgMkLpyt 9xug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755941710; x=1756546510; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:date:from:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=A92qUKVVscD1iUAIIcRKA9oYRSCgvP30+tdPO7B2xVE=; b=OsNtzT78SanGds2EHpbmLi2xToFiJ3UU3Q5lKN38qp8/xoJv6fKy7gbUS2pPwdKqCw C5xNbweBGhS7iPcQa+0o+izQhgF90oW5zGQRuAm3lVzjAkeQpRQ6j0WmrBmFpZ+xNVtj aY+XFXj+LMvgFb9lKu4Yfvl9Kws6hFs+kJLmOeep6+eK4IcUM6l1uEmsIOmMca/I/VBK N4vvN+0jKDIfOs5dETI4q2zspdXTdeBlfVKA99XnZrK+Pe1xdx7Syg9TGM2NI1qLNHfC SkS2KERdNYtvQSwtvv5MbmSVNeKc4BvX0wL7/wkyIpGI+vmqB81l/4O3uW3pwaeumL/u lV7Q== X-Forwarded-Encrypted: i=1; AJvYcCVVnjE909gGau3FNxvdRZj3DmzBWe3Htmt5C51bIXUIKni/XntkuNm3dbc97pMuZxMbuTLGXfdg/kAesDM=@vger.kernel.org X-Gm-Message-State: AOJu0YwwM5qUBk/LCz8J3N16EWtG0x/On1xnpwsAoTeukxfzxEkazWTt 15yLMt7pWa0xWAsHaz0ftHCKwpdxfsMpXJ6EEnua3cM2/jhpxtsFOP63 X-Gm-Gg: ASbGncvL236HRXW0ml/z12Wq7FJWjg/fQGfy6/hT5z6H++edn0mj4EYR57kb4iY+5lF BanHhVtaPbj8I5N9ygcLt3oq9S/dUzpckq1vw7A8WKbkcCxAilybCGkpiQDOQsKHs9X+TNNTBYT Gik0Tj64n/vCQeYb/skZhAzaGIo0qC0LXpJn6pZU9+etyyltNYu/Rd+AU7uWz9qqBTwv10aNPiF 8vaEcgRl/NZtWtQDVoiHTqtVrYHzzLtPopDYKPw2G9DUTBMI+WiuxqRkk9JbPy0HBegSsERfMOa P/8XAz6NYztH5eS3a0qSdTEOCETZ58qKnSugwf4rkXNBEdQ/kSz1gVz7fnDiw7h6 X-Google-Smtp-Source: AGHT+IEKI+WFby0u8zrSUkWE+Z6THT2SoEAd6rk+RgsOklByaudVol34fQCDN7e3412nflAMA9MT2g== X-Received: by 2002:a05:6512:4048:20b0:55f:34e8:b1b8 with SMTP id 2adb3069b0e04-55f34e8ca2fmr503948e87.55.1755941709652; Sat, 23 Aug 2025 02:35:09 -0700 (PDT) Received: from pc636 ([2001:9b1:d5a0:a500::800]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-55f35c9a0bbsm402584e87.121.2025.08.23.02.35.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 23 Aug 2025 02:35:09 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Sat, 23 Aug 2025 11:35:07 +0200 To: Alexander Potapenko Cc: Marco Elver , linux-mm@kvack.org, Andrew Morton , Vlastimil Babka , Michal Hocko , Baoquan He , LKML , Alexander Potapenko , kasan-dev@googlegroups.com Subject: Re: [PATCH 0/8] __vmalloc() and no-block support Message-ID: References: <20250807075810.358714-1-urezki@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hello, Alexander! I am working on making vmalloc to support extra non-blocking flags. Currently i see one more place that i need to address: kmsan_vmap_pages_range_noflush() function which uses hard-coded GFP_KERNEL flags for allocation of two arrays for its internal use only. I have a question to you, can we just get rid of those two allocations? It is the easiest way, if possible. Otherwise i can add "gfp_t gfp_mask" extra parameter and pass there a corresponding gfp_mask flag. See below: diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h index 2b1432cc16d5..e4b34e7a3b11 100644 --- a/include/linux/kmsan.h +++ b/include/linux/kmsan.h @@ -133,6 +133,7 @@ void kmsan_kfree_large(const void *ptr); * @prot: page protection flags used for vmap. * @pages: array of pages. * @page_shift: page_shift passed to vmap_range_noflush(). + * @gfp_mask: gfp_mask to use internally. * * KMSAN maps shadow and origin pages of @pages into contiguous ranges in * vmalloc metadata address range. Returns 0 on success, callers must check @@ -142,7 +143,8 @@ int __must_check kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, pgprot_t prot, struct page **pages, - unsigned int page_shift); + unsigned int page_shift, + gfp_t gfp_mask); /** * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap. @@ -348,7 +350,7 @@ static inline void kmsan_kfree_large(const void *ptr) static inline int __must_check kmsan_vmap_pages_range_noflush( unsigned long start, unsigned long end, pgprot_t prot, - struct page **pages, unsigned int page_shift) + struct page **pages, unsigned int page_shift, gfp_t gfp_mask) { return 0; } diff --git a/mm/internal.h b/mm/internal.h index 45b725c3dc03..6a13b8ee1e6c 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1359,7 +1359,7 @@ size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, #ifdef CONFIG_MMU void __init vmalloc_init(void); int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, - pgprot_t prot, struct page **pages, unsigned int page_shift); + pgprot_t prot, struct page **pages, unsigned int page_shift, gfp_t gfp_mask); unsigned int get_vm_area_page_order(struct vm_struct *vm); #else static inline void vmalloc_init(void) @@ -1368,7 +1368,7 @@ static inline void vmalloc_init(void) static inline int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, - pgprot_t prot, struct page **pages, unsigned int page_shift) + pgprot_t prot, struct page **pages, unsigned int page_shift, gfp_t gfp_mask) { return -EINVAL; } diff --git a/mm/kmsan/init.c b/mm/kmsan/init.c index b14ce3417e65..5b74d6dbf0b8 100644 --- a/mm/kmsan/init.c +++ b/mm/kmsan/init.c @@ -233,5 +233,6 @@ void __init kmsan_init_runtime(void) kmsan_memblock_discard(); pr_info("Starting KernelMemorySanitizer\n"); pr_info("ATTENTION: KMSAN is a debugging tool! Do not use it on production machines!\n"); - kmsan_enabled = true; + /* kmsan_enabled = true; */ + kmsan_enabled = false; } diff --git a/mm/kmsan/shadow.c b/mm/kmsan/shadow.c index 54f3c3c962f0..3cd733663100 100644 --- a/mm/kmsan/shadow.c +++ b/mm/kmsan/shadow.c @@ -215,7 +215,7 @@ void kmsan_free_page(struct page *page, unsigned int order) int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, pgprot_t prot, struct page **pages, - unsigned int page_shift) + unsigned int page_shift, gfp_t gfp_mask) { unsigned long shadow_start, origin_start, shadow_end, origin_end; struct page **s_pages, **o_pages; @@ -230,8 +230,8 @@ int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, return 0; nr = (end - start) / PAGE_SIZE; - s_pages = kcalloc(nr, sizeof(*s_pages), GFP_KERNEL); - o_pages = kcalloc(nr, sizeof(*o_pages), GFP_KERNEL); + s_pages = kcalloc(nr, sizeof(*s_pages), gfp_mask); + o_pages = kcalloc(nr, sizeof(*o_pages), gfp_mask); if (!s_pages || !o_pages) { err = -ENOMEM; goto ret; diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c index cd69caf6aa8d..4f5937090590 100644 --- a/mm/percpu-vm.c +++ b/mm/percpu-vm.c @@ -194,7 +194,7 @@ static int __pcpu_map_pages(unsigned long addr, struct page **pages, int nr_pages) { return vmap_pages_range_noflush(addr, addr + (nr_pages << PAGE_SHIFT), - PAGE_KERNEL, pages, PAGE_SHIFT); + PAGE_KERNEL, pages, PAGE_SHIFT, GFP_KERNEL); } /** diff --git a/mm/vmalloc.c b/mm/vmalloc.c index ee197f5b8cf0..9be01dcca690 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -671,16 +671,28 @@ int __vmap_pages_range_noflush(unsigned long addr, unsigned long end, } int vmap_pages_range_noflush(unsigned long addr, unsigned long end, - pgprot_t prot, struct page **pages, unsigned int page_shift) + pgprot_t prot, struct page **pages, unsigned int page_shift, + gfp_t gfp_mask) { int ret = kmsan_vmap_pages_range_noflush(addr, end, prot, pages, - page_shift); + page_shift, gfp_mask); if (ret) return ret; return __vmap_pages_range_noflush(addr, end, prot, pages, page_shift); } +static int __vmap_pages_range(unsigned long addr, unsigned long end, + pgprot_t prot, struct page **pages, unsigned int page_shift, + gfp_t gfp_mask) +{ + int err; + + err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift, gfp_mask); + flush_cache_vmap(addr, end); + return err; +} + /** * vmap_pages_range - map pages to a kernel virtual address * @addr: start of the VM area to map @@ -696,11 +708,7 @@ int vmap_pages_range_noflush(unsigned long addr, unsigned long end, int vmap_pages_range(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift) { - int err; - - err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift); - flush_cache_vmap(addr, end); - return err; + return __vmap_pages_range(addr, end, prot, pages, page_shift, GFP_KERNEL); } static int check_sparse_vm_area(struct vm_struct *area, unsigned long start, @@ -3804,8 +3812,8 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, flags = memalloc_noio_save(); do { - ret = vmap_pages_range(addr, addr + size, prot, area->pages, - page_shift); + ret = __vmap_pages_range(addr, addr + size, prot, area->pages, + page_shift, gfp_mask); if (nofail && (ret < 0)) schedule_timeout_uninterruptible(1); } while (nofail && (ret < 0)); Thanks! -- Uladzislau Rezki