From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751301AbdFADgr (ORCPT ); Wed, 31 May 2017 23:36:47 -0400 Received: from m12-15.163.com ([220.181.12.15]:47575 "EHLO m12-15.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbdFADgq (ORCPT ); Wed, 31 May 2017 23:36:46 -0400 Message-ID: <592F8C4B.3080109@163.com> Date: Thu, 01 Jun 2017 11:38:51 +0800 From: Jia-Ju Bai User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120410 Thunderbird/11.0.1 MIME-Version: 1.0 To: Sumit Saxena CC: Kashyap Desai , Shivasharan Srikanteshwara , jejb@linux.vnet.ibm.com, martin.petersen@oracle.com, "PDL,MEGARAIDLINUX" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] megaraid: Fix a sleep-in-atomic bug References: <1496199416-2556-1-git-send-email-baijiaju1990@163.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CM-TRANSID: D8CowAAXH1PDiy9Z_6BpIQ--.43832S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7try7Wry5Xw17JFyDKw13twb_yoW8Aw4DpF WxJFyYkF18X34I9a1kur1YvFWj9w4kXa4akrWjq34Y9F4avr1F9ws2gF1avF9FqrZ7uF4x ZF17Xryvg3WqyrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jRhFxUUUUU= X-Originating-IP: [166.111.70.19] X-CM-SenderInfo: xedlyx5dmximizq6il2tof0z/xtbBRQTpelO-7WOmhQAAsT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/31/2017 06:18 PM, Sumit Saxena wrote: >> -----Original Message----- >> From: Jia-Ju Bai [mailto:baijiaju1990@163.com] >> Sent: Wednesday, May 31, 2017 8:27 AM >> To: kashyap.desai@broadcom.com; sumit.saxena@broadcom.com; >> shivasharan.srikanteshwara@broadcom.com; jejb@linux.vnet.ibm.com; >> martin.petersen@oracle.com >> Cc: megaraidlinux.pdl@broadcom.com; linux-scsi@vger.kernel.org; linux- >> kernel@vger.kernel.org; Jia-Ju Bai >> Subject: [PATCH] megaraid: Fix a sleep-in-atomic bug >> >> The driver may sleep under a spin lock, and the function call path is: >> mraid_mm_attach_buf (acquire the lock by spin_lock_irqsave) >> pci_pool_alloc(GFP_KERNEL) --> may sleep >> >> To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC". >> >> Signed-off-by: Jia-Ju Bai >> --- >> drivers/scsi/megaraid/megaraid_mm.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/scsi/megaraid/megaraid_mm.c >> b/drivers/scsi/megaraid/megaraid_mm.c >> index 4cf9ed9..c43afb8 100644 >> --- a/drivers/scsi/megaraid/megaraid_mm.c >> +++ b/drivers/scsi/megaraid/megaraid_mm.c >> @@ -574,7 +574,7 @@ >> >> kioc->pool_index = right_pool; >> kioc->free_buf = 1; >> - kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL, >> + kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_ATOMIC, >> &kioc->buf_paddr); >> spin_unlock_irqrestore(&pool->lock, flags); > This is very old driver and reached EOL. Did you face any issue because of > this bug or discover this through code review? > Anyways patch looks good to me. > > Acked-by: Sumit Saxena > >> -- >> 1.7.9.5 >> Hi, This bug is found by a static analysis tool and my code review. Jia-Ju Bai