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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71932C4332F for ; Tue, 14 Dec 2021 16:22:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235834AbhLNQWc (ORCPT ); Tue, 14 Dec 2021 11:22:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235775AbhLNQWW (ORCPT ); Tue, 14 Dec 2021 11:22:22 -0500 Received: from mail-wr1-x44a.google.com (mail-wr1-x44a.google.com [IPv6:2a00:1450:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40F27C06173F for ; Tue, 14 Dec 2021 08:22:22 -0800 (PST) Received: by mail-wr1-x44a.google.com with SMTP id d7-20020a5d6447000000b00186a113463dso4855518wrw.10 for ; Tue, 14 Dec 2021 08:22:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=ITyhCHO1UiX2DPCFkkqWNUvg7KfOdfMNTQoZ+QNE7bU=; b=VBMgNGVHDe18Og0TwNncVl3ew6zMtrxStb1uB6st2XRmRBQ3tEQXjuXrYuoSm0prGY K20SlkDHnXzsSFK83A1uOoPf7s8MoCjkMO60Pz4Bsrw5Zv3EFffTyroafyTpApie3f5m nG6BxjJm7YHC0e0oJK8lMT2uRqxC1uWTQHEppiGgKAXQKqpaYr/YGuy4I6cjhoRPfjGj aJvrRtPNJ75tOy8zCBClXxAQIrWbUSjbUhHVVIs8uDdSTyy0Rb+tOXzVFasYYZt5TqIc i0ARL88+0gAlT2wgHGVsXU2gLTSMd4ju6zO7fLp36fAYYiZyasvP1IysAaRLHtGTDfz/ h1sA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ITyhCHO1UiX2DPCFkkqWNUvg7KfOdfMNTQoZ+QNE7bU=; b=Uew8fdQvcAjPrEfr/VDc/ATiy6IKUT1Mx6GAhyajv/rcXQ+DTn2RvpKDEP3rDQE9WS 0dHOcDSF+lSBi5KcfyaQfU5nQ+qChFFOcZCWockTrxWRJuB45dwxQqmyH+2QikIj6+rY kZ1YyXaJnBUkExtPYcwMQyV7LYN4gRubwx5xv8TwPmxwnZDbdARYCA5QV1nscUuF+1pp nK03MWk0dRdj+Sv+EfHlA+2JjzhlecXcuQjk4AUNTuNfscv8mDPstPPkiB2a5PaFf95B wD856nOGbchUxZE2i3WeLC7XwopG4Y8gnt/aG1seTFyuKgkZICN04Qmy4JJoFibGHIQK wjIQ== X-Gm-Message-State: AOAM530g6N4Ic3QWMcK8sOz0l1TDFxag3AdCT5UyaI9nfAvla1wZ3NeD FIvhWrgyMyREiWXTgA/NlfZ6dmNHsV4= X-Google-Smtp-Source: ABdhPJynp7SO7nkkbS3IYqSUnN1vnEfdIZ95PUH2Mr7X6JqBGNbKrX/KoqtS/NjRGYPpNTG+FE367wmyggw= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:357e:2b9d:5b13:a652]) (user=glider job=sendgmr) by 2002:a5d:6ac2:: with SMTP id u2mr6665311wrw.486.1639498940724; Tue, 14 Dec 2021 08:22:20 -0800 (PST) Date: Tue, 14 Dec 2021 17:20:17 +0100 In-Reply-To: <20211214162050.660953-1-glider@google.com> Message-Id: <20211214162050.660953-11-glider@google.com> Mime-Version: 1.0 References: <20211214162050.660953-1-glider@google.com> X-Mailer: git-send-email 2.34.1.173.g76aa8bc2d0-goog Subject: [PATCH 10/43] kmsan: pgtable: reduce vmalloc space From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org KMSAN is going to use 3/4 of existing vmalloc space to hold the metadata, therefore we lower VMALLOC_END to make sure vmalloc() doesn't allocate past the first 1/4. Signed-off-by: Alexander Potapenko --- Link: https://linux-review.googlesource.com/id/I9d8b7f0a88a639f1263bc693cbd5c136626f7efd --- arch/x86/include/asm/pgtable_64_types.h | 41 ++++++++++++++++++++++++- arch/x86/mm/init_64.c | 2 +- 2 files changed, 41 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 91ac106545703..7f15d43754a34 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -139,7 +139,46 @@ extern unsigned int ptrs_per_p4d; # define VMEMMAP_START __VMEMMAP_BASE_L4 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */ -#define VMALLOC_END (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1) +#define VMEMORY_END (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1) + +#ifndef CONFIG_KMSAN +#define VMALLOC_END VMEMORY_END +#else +/* + * In KMSAN builds vmalloc area is four times smaller, and the remaining 3/4 + * are used to keep the metadata for virtual pages. The memory formerly + * belonging to vmalloc area is now laid out as follows: + * + * 1st quarter: VMALLOC_START to VMALLOC_END - new vmalloc area + * 2nd quarter: KMSAN_VMALLOC_SHADOW_START to + * VMALLOC_END+KMSAN_VMALLOC_SHADOW_OFFSET - vmalloc area shadow + * 3rd quarter: KMSAN_VMALLOC_ORIGIN_START to + * VMALLOC_END+KMSAN_VMALLOC_ORIGIN_OFFSET - vmalloc area origins + * 4th quarter: KMSAN_MODULES_SHADOW_START to KMSAN_MODULES_ORIGIN_START + * - shadow for modules, + * KMSAN_MODULES_ORIGIN_START to + * KMSAN_MODULES_ORIGIN_START + MODULES_LEN - origins for modules. + */ +#define VMALLOC_QUARTER_SIZE ((VMALLOC_SIZE_TB << 40) >> 2) +#define VMALLOC_END (VMALLOC_START + VMALLOC_QUARTER_SIZE - 1) + +/* + * vmalloc metadata addresses are calculated by adding shadow/origin offsets + * to vmalloc address. + */ +#define KMSAN_VMALLOC_SHADOW_OFFSET VMALLOC_QUARTER_SIZE +#define KMSAN_VMALLOC_ORIGIN_OFFSET (VMALLOC_QUARTER_SIZE << 1) + +#define KMSAN_VMALLOC_SHADOW_START (VMALLOC_START + KMSAN_VMALLOC_SHADOW_OFFSET) +#define KMSAN_VMALLOC_ORIGIN_START (VMALLOC_START + KMSAN_VMALLOC_ORIGIN_OFFSET) + +/* + * The shadow/origin for modules are placed one by one in the last 1/4 of + * vmalloc space. + */ +#define KMSAN_MODULES_SHADOW_START (VMALLOC_END + KMSAN_VMALLOC_ORIGIN_OFFSET + 1) +#define KMSAN_MODULES_ORIGIN_START (KMSAN_MODULES_SHADOW_START + MODULES_LEN) +#endif /* CONFIG_KMSAN */ #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) /* The module sections ends with the start of the fixmap */ diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 36098226a9573..8e884e44a8d1e 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1287,7 +1287,7 @@ static void __init preallocate_vmalloc_pages(void) unsigned long addr; const char *lvl; - for (addr = VMALLOC_START; addr <= VMALLOC_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) { + for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) { pgd_t *pgd = pgd_offset_k(addr); p4d_t *p4d; pud_t *pud; -- 2.34.1.173.g76aa8bc2d0-goog