From patchwork Wed Feb 3 00:31:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suren Baghdasaryan X-Patchwork-Id: 12063143 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77E77C433E0 for ; Wed, 3 Feb 2021 00:31:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E63BD64F6C for ; Wed, 3 Feb 2021 00:31:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E63BD64F6C Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 04D2A6B0005; Tue, 2 Feb 2021 19:31:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id F184B6B006C; Tue, 2 Feb 2021 19:31:37 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DE1BC6B006E; Tue, 2 Feb 2021 19:31:37 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0135.hostedemail.com [216.40.44.135]) by kanga.kvack.org (Postfix) with ESMTP id C52746B0005 for ; Tue, 2 Feb 2021 19:31:37 -0500 (EST) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 907E98249980 for ; Wed, 3 Feb 2021 00:31:37 +0000 (UTC) X-FDA: 77775078234.17.soap91_0f11373275cf Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id 701B1180D0180 for ; Wed, 3 Feb 2021 00:31:37 +0000 (UTC) X-HE-Tag: soap91_0f11373275cf X-Filterd-Recvd-Size: 4190 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) by imf43.hostedemail.com (Postfix) with ESMTP for ; Wed, 3 Feb 2021 00:31:36 +0000 (UTC) Received: by mail-yb1-f201.google.com with SMTP id c12so25529595ybf.1 for ; Tue, 02 Feb 2021 16:31:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:message-id:mime-version:subject:from:to:cc; bh=SOXagrKaf/SGUJ0It1u1ORMjiyQ7gfGWlZufV5zUWJE=; b=Du2OOc57uVZ5uhkj2egHtA2wa0SFb9m9+y9NUmdFQiDq6WF2NakwTwFWFMXWVb3EBL 6yZFOR+lPWlQVyiwF9d8puYRUFCxEGC1+R29nJZU8FOnSiKOy4numK8O9O1pWyf7m1VF 8chND7Te/w1IUSVTEvSM8juDTdD/Y9h/tjYjVRIOVVMIrQ95XmURDbfFMzRgUhQ3iaW/ ykaovl20AETBww7DpJLvE4T3DJlaYWWtMgd5XgGU2SXCdiQbXAqgAOVTrRqQT/IObwbO wz8tYr1IEZgh7+XbFH1Jf8hI3AA5tNm6TDQlfW/GVzGjDcRPqQagtp6MdCrThoU9FjSr Qs3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=SOXagrKaf/SGUJ0It1u1ORMjiyQ7gfGWlZufV5zUWJE=; b=NZGinCm+U2eE/GQRL31L/yxFdiuZc7W5HVgNEGhM31ktD6SsSmutIO+lDq3m9dUv5n KhgBEDvBJHEIb1sZKVJ1BWmQzfpf0IGidrp70VVURcZ4/xiV68x0GCPlAhNsLh9+hwEX Ns7XXOKfzAwZmnjNQ8p/XucW9cirdPzZ4YRDsgRwQoX/M+zk2HPDvFzEmmWoi8goWCnu ZPh0h9xsup9i0iiXXXVD4+ArGCaeUyVI0n8UpIO/h65BDPu9fLSLjujg/HDvwBxNhXeC wzy78Qsu6ozR2vUJo7QQdM2QVbzwP1iftuZ2nDeAH+wyo1CoC7CUwdwXdXxgAFyyGBcQ kNfw== X-Gm-Message-State: AOAM533eMpC1Ns/kzXS/8vS2fIStdhCkbb9j4H+BFXXdfHcIHweFeG1j Vi73LjI8BlhtCfWKwHp0HLEjX55oevs= X-Google-Smtp-Source: ABdhPJx1oe0/DgxGORm9UrMRCk0QL4fxRFPA1BcJxhU6LPzwDc8fSpOWryrH8a7W+r9pJcxrhxvwKlDBtU0= X-Received: from surenb1.mtv.corp.google.com ([2620:15c:211:200:9194:cd6:1ec:3e2d]) (user=surenb job=sendgmr) by 2002:a05:6902:1025:: with SMTP id x5mr707532ybt.21.1612312296088; Tue, 02 Feb 2021 16:31:36 -0800 (PST) Date: Tue, 2 Feb 2021 16:31:33 -0800 Message-Id: <20210203003134.2422308-1-surenb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH 1/2] mm: replace BUG_ON in vm_insert_page with a return of an error From: Suren Baghdasaryan To: sumit.semwal@linaro.org Cc: akpm@linux-foundation.org, hch@infradead.org, lmark@codeaurora.org, labbott@redhat.com, Brian.Starkey@arm.com, john.stultz@linaro.org, christian.koenig@amd.com, cgoldswo@codeaurora.org, orjan.eide@arm.com, robin.murphy@arm.com, jajones@nvidia.com, minchan@kernel.org, hridya@google.com, sspatil@google.com, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@android.com, surenb@google.com X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Replace BUG_ON(vma->vm_flags & VM_PFNMAP) in vm_insert_page with WARN_ON_ONCE and returning an error. This is to ensure users of the vm_insert_page that set VM_PFNMAP are notified of the wrong flag usage and get an indication of an error without panicing the kernel. This will help identifying drivers that need to clear VM_PFNMAP before using dmabuf system heap which is moving to use vm_insert_page. Suggested-by: Christoph Hellwig Signed-off-by: Suren Baghdasaryan Reviewed-by: Miaohe Lin --- mm/memory.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memory.c b/mm/memory.c index feff48e1465a..e503c9801cd9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1827,7 +1827,8 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, return -EINVAL; if (!(vma->vm_flags & VM_MIXEDMAP)) { BUG_ON(mmap_read_trylock(vma->vm_mm)); - BUG_ON(vma->vm_flags & VM_PFNMAP); + if (WARN_ON_ONCE(vma->vm_flags & VM_PFNMAP)) + return -EINVAL; vma->vm_flags |= VM_MIXEDMAP; } return insert_page(vma, addr, page, vma->vm_page_prot);