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 98FD3C77B6E for ; Thu, 13 Apr 2023 13:12:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230406AbjDMNM6 (ORCPT ); Thu, 13 Apr 2023 09:12:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230361AbjDMNMu (ORCPT ); Thu, 13 Apr 2023 09:12:50 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D501EA5EC for ; Thu, 13 Apr 2023 06:12:35 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id 4fb4d7f45d1cf-504c8399f19so1289773a12.0 for ; Thu, 13 Apr 2023 06:12:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681391554; x=1683983554; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=BH4qKloTg3p5myDfS9qJ+XOa2IgLWTGcxSlYlXSqJNo=; b=D1+Gxpsma/kKehsYuehV5AlXbCxc9+6yPgVnS4mtrcrcUcfPbXHC2IVd4NdgcWvxKa sFORPx9k38EwNTdIx61YKgywtcophMGlm0SneHUBf4hypraueUI/TCDxI29jaZxY1vIy ltbilESRPv7Q0LzZkEMlnMV0LuOIkteNE9tSmGodmB8jIC9XLr/RqiX83LjxWJDm0fVC EzV7E9dIAd5BiJZP+J1mqdK7NdGn/rWTij/eOFuQ+J2dgfLFHk6TbzlAIkaBXBH7NQT0 efLIkeRRi5i07YY6nTPb/kS2kA4Hs5mxoljJv1OfBU3BsRfbtn2Ns7T6FwUjRXC1Rn46 5MNg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681391554; x=1683983554; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=BH4qKloTg3p5myDfS9qJ+XOa2IgLWTGcxSlYlXSqJNo=; b=Z+PI8+aF1sKXSmsAeX7NmFkD9Oe6C33iI25BGmbk0MK0XNrPiQdhErN2mBvZrZe38M rUMwRxB5Cc9r5K+Xu/NO+rEASEwEHfG2CAUIZjEjZTHtm6dntmi33mvAmX6sBF7/xYmt z5o6lRkvNB8sDKpC0j74RVy4q9CI17Iv126+p0q9MOgOVlFwK5OkrZq3hJDgIonMctHT peQR/cXZLm20g1nlxloKbsw8ZQNRhM5/FN08ErpsCgu38aC0MqXtGHgYFu8vkyzBXyuo n11yAfN0FOVln3RX2O4h7wO9bt/QPahcm9+4uRpi+9m7O3iw1kDMWvd2UsHgy2eumsP2 +Sjg== X-Gm-Message-State: AAQBX9eq9KsYNjc9uTFkYvO/gbe0fgKkBdqW0V5QcLA4lM1DxAPn7WHc /nx7SU3EzPgje2F901Zff8S/qQDDU6U= X-Google-Smtp-Source: AKy350YjqcoIpDQnhokGemab6QINRaBafWRCSTgHRnGh9LmJmojNFRKF3kptG318ucQsrxRVaIe1NJVIppQ= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:eb2b:4d7d:1d7f:9316]) (user=glider job=sendgmr) by 2002:a50:9ee7:0:b0:505:842:37b0 with SMTP id a94-20020a509ee7000000b00505084237b0mr1236251edf.3.1681391554378; Thu, 13 Apr 2023 06:12:34 -0700 (PDT) Date: Thu, 13 Apr 2023 15:12:22 +0200 In-Reply-To: <20230413131223.4135168-1-glider@google.com> Mime-Version: 1.0 References: <20230413131223.4135168-1-glider@google.com> X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230413131223.4135168-3-glider@google.com> Subject: [PATCH v2 3/4] mm: kmsan: apply __must_check to non-void functions From: Alexander Potapenko To: glider@google.com Cc: urezki@gmail.com, hch@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, elver@google.com, dvyukov@google.com, kasan-dev@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Non-void KMSAN hooks may return error codes that indicate that KMSAN failed to reflect the changed memory state in the metadata (e.g. it could not create the necessary memory mappings). In such cases the callers should handle the errors to prevent the tool from using the inconsistent metadata in the future. We mark non-void hooks with __must_check so that error handling is not skipped. Signed-off-by: Alexander Potapenko --- include/linux/kmsan.h | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h index 30b17647ce3c7..e0c23a32cdf01 100644 --- a/include/linux/kmsan.h +++ b/include/linux/kmsan.h @@ -54,7 +54,8 @@ void __init kmsan_init_runtime(void); * Freed pages are either returned to buddy allocator or held back to be used * as metadata pages. */ -bool __init kmsan_memblock_free_pages(struct page *page, unsigned int order); +bool __init __must_check kmsan_memblock_free_pages(struct page *page, + unsigned int order); /** * kmsan_alloc_page() - Notify KMSAN about an alloc_pages() call. @@ -137,9 +138,11 @@ void kmsan_kfree_large(const void *ptr); * vmalloc metadata address range. Returns 0 on success, callers must check * for non-zero return value. */ -int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, - pgprot_t prot, struct page **pages, - unsigned int page_shift); +int __must_check kmsan_vmap_pages_range_noflush(unsigned long start, + unsigned long end, + pgprot_t prot, + struct page **pages, + unsigned int page_shift); /** * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap. @@ -163,9 +166,9 @@ void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end); * virtual memory. Returns 0 on success, callers must check for non-zero return * value. */ -int kmsan_ioremap_page_range(unsigned long addr, unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int page_shift); +int __must_check kmsan_ioremap_page_range(unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int page_shift); /** * kmsan_iounmap_page_range() - Notify KMSAN about a iounmap_page_range() call. @@ -237,8 +240,8 @@ static inline void kmsan_init_runtime(void) { } -static inline bool kmsan_memblock_free_pages(struct page *page, - unsigned int order) +static inline bool __must_check kmsan_memblock_free_pages(struct page *page, + unsigned int order) { return true; } @@ -251,10 +254,9 @@ static inline void kmsan_task_exit(struct task_struct *task) { } -static inline int kmsan_alloc_page(struct page *page, unsigned int order, - gfp_t flags) +static inline void kmsan_alloc_page(struct page *page, unsigned int order, + gfp_t flags) { - return 0; } static inline void kmsan_free_page(struct page *page, unsigned int order) @@ -283,11 +285,9 @@ static inline void kmsan_kfree_large(const void *ptr) { } -static inline int kmsan_vmap_pages_range_noflush(unsigned long start, - unsigned long end, - pgprot_t prot, - struct page **pages, - unsigned int page_shift) +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) { return 0; } @@ -297,10 +297,11 @@ static inline void kmsan_vunmap_range_noflush(unsigned long start, { } -static inline int kmsan_ioremap_page_range(unsigned long start, - unsigned long end, - phys_addr_t phys_addr, pgprot_t prot, - unsigned int page_shift) +static inline int __must_check kmsan_ioremap_page_range(unsigned long start, + unsigned long end, + phys_addr_t phys_addr, + pgprot_t prot, + unsigned int page_shift) { return 0; } -- 2.40.0.577.gac1e443424-goog