From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4/blBIAYJ5hAS/jqrV3OnTo4oTIsDoOCVDJazpCQWhjH0Se1KQcslsMIQazRGrxSjSc7j1R ARC-Seal: i=1; a=rsa-sha256; t=1523370340; cv=none; d=google.com; s=arc-20160816; b=bR26wLknz8XdqWVBLaaUTjvGsZDnn2GlNFbZL+4yPInQWvqggiuzgYawHD+KtUNDPM +QxeXNMP5+I9QCekc6xJAEY89yKz9ABP9wlFTx/Vofnq9yrodGQ7jHi7I8QsjMGIUxNI V7SI3fPvBFj8Fgo4xYJmcTxzcAZZ97765HHP/DtbGT+cObmjH5uCkJB9B+pVC/dcaLR0 1GS8vEP/FcAunC+mg4fwymxsjKNaDV6JGJTWfjze2AXqeNzZSPz9p1/ngRB3o8J+0ZVk ukRhVmpFPlUu0kRBltVk8PsbeATYFa8WeHHw1NdYrjrkvLEufGDflFwE8Dclein6EI2O 6YKg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-language:content-transfer-encoding:in-reply-to:mime-version :user-agent:date:message-id:autocrypt:openpgp:from:references:cc:to :subject:dkim-signature:arc-authentication-results; bh=TtFMcNwsMm60LY/CPVtyNhoG6XdHz+PVRhAlMj8IyAk=; b=l0vTEKQ5xQwQQaXdkFKnXEJRZJIDBcZKwPp7yHDyGA9y0SPZd/G8tPnRaLlaAlSjej Z9/JD4Ca1E7AUyFB6b6ZBTn0uo1BntBmH2GYgP2QZmdfvFooIZ2Gy5xAWNp/N+Vqrdty fr7CAmoJKrqnm2j0Wdr+688S/RRIzPmKrnJXUUR7JuBqdDSbb8RU4PiwvFkUyLpOGOU2 CHtW1vkWgI95r7IipDIBw/jJEZLRVdT6Y4QFAIxi448pggXhIP+xNHWJn33vaD8TeIg8 7MkGhFVBuQ7V03mPrgByV6lv9k/WkX9nvUoRPlijTK5Aj1pELMV7ZvncJFBJQChrId1C vGRQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2017-10-26 header.b=ViNLulBC; spf=pass (google.com: domain of boris.ostrovsky@oracle.com designates 156.151.31.85 as permitted sender) smtp.mailfrom=boris.ostrovsky@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2017-10-26 header.b=ViNLulBC; spf=pass (google.com: domain of boris.ostrovsky@oracle.com designates 156.151.31.85 as permitted sender) smtp.mailfrom=boris.ostrovsky@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Subject: Re: [PATCH 1/4] xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_probe To: Jia-Ju Bai , jgross@suse.com, gregkh@linuxfoundation.org Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org References: <1523286216-26345-1-git-send-email-baijiaju1990@gmail.com> From: Boris Ostrovsky Openpgp: preference=signencrypt Autocrypt: addr=boris.ostrovsky@oracle.com; 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Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1523286216-26345-1-git-send-email-baijiaju1990@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8858 signatures=668698 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1804100142 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1597281379484745930?= X-GMAIL-MSGID: =?utf-8?q?1597369578139066473?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 04/09/2018 11:03 AM, Jia-Ju Bai wrote: > pcistub_probe() is never called in atomic context. > This function is only set as ".probe" in struct pci_driver. > > Despite never getting called from atomic context, > pcistub_probe() calls kmalloc() with GFP_ATOMIC, > which does not sleep for allocation. > GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, > which can sleep and improve the possibility of sucessful allocation. > > This is found by a static analysis tool named DCNS written by myself. > And I also manually check it. > > Signed-off-by: Jia-Ju Bai What about use of GFP_ATOMIC in pcistub_reg_add()? -boris > --- > drivers/xen/xen-pciback/pci_stub.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c > index 9e480fd..95e6ddd 100644 > --- a/drivers/xen/xen-pciback/pci_stub.c > +++ b/drivers/xen/xen-pciback/pci_stub.c > @@ -577,7 +577,7 @@ static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id) > } > > if (!match) { > - pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_ATOMIC); > + pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL); > if (!pci_dev_id) { > err = -ENOMEM; > goto out;