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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 49A70C06511 for ; Wed, 3 Jul 2019 22:02:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 220FF218A0 for ; Wed, 3 Jul 2019 22:02:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="QkYiGjbM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727435AbfGCWCY (ORCPT ); Wed, 3 Jul 2019 18:02:24 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:33856 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727416AbfGCWCW (ORCPT ); Wed, 3 Jul 2019 18:02:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=TH7ilSpN+2j82AKqVSfBr/e3/+W2L5xJvYOO3yTY4Is=; b=QkYiGjbMBjTGLVROOh+GRbmRJb MyoPGFJE+6teMNn9c5SEVHNaLJh/dDNSFYCEY+IvBJKEGW9ohDBcsp6CVPN0VrZ0J7fDngCYsPSv4 CTcFISy34r27v4v0H03+M4tT46hjxR7FS9ebz/zaYpADue3mFBLXKkQiySiYo0OXMfYuIEZSyIeYM BCuxayLeVqoTiSZtVLEC80SQUqJFqA/SAdaH6UO6w3Q1gsl//cwPUe6JlfqruSzJ+jjOQ7dz9kSgZ fn9KEBBzwR+rePovn050pvLCHNfewpmtkFC8H0ZPqp/ZOMDz4QtUvPdjcKRyVJo7D+Wq8Gx7oUV5c ydw5RV1w==; Received: from rap-us.hgst.com ([199.255.44.250] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hinKS-0004Eh-Da; Wed, 03 Jul 2019 22:02:16 +0000 From: Christoph Hellwig To: =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Jason Gunthorpe , Ben Skeggs Cc: Ralph Campbell , linux-mm@kvack.org, nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/6] nouveau: unlock mmap_sem on all errors from nouveau_range_fault Date: Wed, 3 Jul 2019 15:02:12 -0700 Message-Id: <20190703220214.28319-5-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190703220214.28319-1-hch@lst.de> References: <20190703220214.28319-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently nouveau_svm_fault expects nouveau_range_fault to never unlock mmap_sem, but the latter unlocks it for a random selection of error codes. Fix this up by always unlocking mmap_sem for non-zero return values in nouveau_range_fault, and only unlocking it in the caller for successful returns. Signed-off-by: Christoph Hellwig --- drivers/gpu/drm/nouveau/nouveau_svm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index 9a9f71e4be29..d97d862e8b7d 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -501,8 +501,10 @@ nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range) ret = hmm_range_register(range, mirror, range->start, range->end, PAGE_SHIFT); - if (ret) + if (ret) { + up_read(&range->vma->vm_mm->mmap_sem); return (int)ret; + } if (!hmm_range_wait_until_valid(range, NOUVEAU_RANGE_FAULT_TIMEOUT)) { up_read(&range->vma->vm_mm->mmap_sem); @@ -511,11 +513,9 @@ nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range) ret = hmm_range_fault(range, true); if (ret <= 0) { - if (ret == -EBUSY || !ret) { - up_read(&range->vma->vm_mm->mmap_sem); - ret = -EBUSY; - } else if (ret == -EAGAIN) + if (ret == 0) ret = -EBUSY; + up_read(&range->vma->vm_mm->mmap_sem); hmm_range_unregister(range); return ret; } @@ -713,8 +713,8 @@ nouveau_svm_fault(struct nvif_notify *notify) NULL); svmm->vmm->vmm.object.client->super = false; mutex_unlock(&svmm->mutex); + up_read(&svmm->mm->mmap_sem); } - up_read(&svmm->mm->mmap_sem); /* Cancel any faults in the window whose pages didn't manage * to keep their valid bit, or stay writeable when required. -- 2.20.1