From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: ARC-Seal: i=1; a=rsa-sha256; t=1523286227; cv=none; d=google.com; s=arc-20160816; b=g6g09g1oK+bDcD4vAOVLGYYGL84yqIVUGqywKIEYvv80QT2A6qKQgvErhpmiJ2G/46 Eoe37Rglj4+stwSpd8GlLv730/f/QCOAVHyDq5CE32vtVYKuRWVvmkEPZh33h1QB/r16 o+3xKXeB40nIXo08COSq8eVahh1coem56zFT3dGjhwIxtKJTFAo83RSyykK3Ceyti4AM A+in8pNGNEeSSPDj2R3qHnTI/vL9YddVgvxtwocPBHXCormzmF100f/RAi0Sv4Ozktkp VBG8p40iTFiQTZRdEN9XOlG0NWflLrUOgE+ubB5/BiR3tj76Hj9JWVIODbapiLVb2RFH JG2A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:date:subject:cc:to:from:dkim-signature :arc-authentication-results; bh=ZXYPyUPFYwhXJy/Xb/U+NjeloED+l0xg9qUfo0SfosE=; b=vjLNhjz8ZJcKnKw02sFmMan2++apt57LmdQL9RrR/NrYgXftcU4v9pXafls8fq+5mc Kyk5HfHplIE/P4G9p98QRUapDHiCWwLoZCOCmLX69tjzE8w540czT78YUL1v/6QvACHZ ft9RYfsUFEawki1dOcg3FFwrENqVKx9muLmxBd7oxTiWaEJjnjhjOdr5fAcJagCHupgI P9mBk7C80PnLBYwbRH05+2LA+Q0e/5H/K6hzPjDf8+BxITSizugL4dHShV8r5gSv4mma YKOvftg2dz9UmgIT6EhK0/MvZPGGi3q3iEYO2sCjajEwfmbwTfpRxSmkp9yWag+0QMUN 1C3A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=GStMIGOr; spf=pass (google.com: domain of baijiaju1990@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=baijiaju1990@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=GStMIGOr; spf=pass (google.com: domain of baijiaju1990@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=baijiaju1990@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com X-Google-Smtp-Source: AIpwx4+pVhEBG0qup9zD9WW5S/mmEPclyxZcwwaBZrGAzWIqX3+1d1LY4f8whNow4UR6xAcGEYWJ0A== From: Jia-Ju Bai To: boris.ostrovsky@oracle.com, jgross@suse.com, gregkh@linuxfoundation.org Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH 1/4] xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_probe Date: Mon, 9 Apr 2018 23:03:36 +0800 Message-Id: <1523286216-26345-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.9.1 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1597281379484745930?= X-GMAIL-MSGID: =?utf-8?q?1597281379484745930?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 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 --- 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; -- 1.9.1