From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELs04jlMlI+VaF7/UVuXIYxVYGnyhdmwtF+9/YBwg1rNtf/5oyxSt2dI5Q55oLzpKflirHQD ARC-Seal: i=1; a=rsa-sha256; t=1520284835; cv=none; d=google.com; s=arc-20160816; b=iqDzWpPRdammRkmEZHZAVMbRgtpfFxb6qpyze1qY12IumqHowKIx2ZoiQB83Rj3fU/ AlSa8nz7F+t0i45RXKLL1SReamzPUg/G0Dk9issrOPS7v3Nz0F9jqySKMexDLj2FRJ9y EXAROHtw3+dOe9KJivUqw9o4n+bZn602g1RUk6YaCqWTOMgAocrO/FCrLKYBih+yFNNv bDjTvaNb4kEnXnt/lpbUEnIH23d6Qx/TCE7Q34kNzuVEBjZihGSjShRkboyF5n4dSEQS sHLNTFWyD/olaMSbqUkUc9kc7gshOgKUgEs0oMUxznC/YiQpleizI3FqswZXy6ir/+eD hbHg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:content-language:in-reply-to:mime-version :user-agent:date:message-id:organization:from:references:cc:to :subject:dkim-signature:arc-authentication-results; bh=MolPSDfS403T0RrSU7LEx6mK0RI1L49XN8lxBKQouNo=; b=gczWxBetPjVo9u5nfSRvvh2iyZIqSKQ+Tc5P49eeZpSTKhytzGYeSZCcEPTIDeDsiT 584PUznT401g9sziXfkLaumSfQEvXQqfSSfRu6hVCRrNZPRwBSRLof2jw3uSIRTGCiYm GzKE37lPJzoHmB959nNALviDtoqRpT2OzRSK7RluGHI3vmkOOvXWDDlfKveP1SDPygG5 a/ELdkC9EUHy5howp0c3N5ybZfqa3fwoagiwQQOnazdrNWQ4tpjfSxzS0NziDkhKV8KB g8Ujm+z4gUPcDCPR7VjgAYfgmif3hWj/ZNiVLe1e8z4sstcEvefnk9ITHyNtlSF9LYWs EbrA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2017-10-26 header.b=qC8N4zr1; spf=pass (google.com: domain of khalid.aziz@oracle.com designates 141.146.126.78 as permitted sender) smtp.mailfrom=khalid.aziz@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=qC8N4zr1; spf=pass (google.com: domain of khalid.aziz@oracle.com designates 141.146.126.78 as permitted sender) smtp.mailfrom=khalid.aziz@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Subject: Re: [PATCH v12 10/11] sparc64: Add support for ADI (Application Data Integrity) To: Dave Hansen , davem@davemloft.net, akpm@linux-foundation.org Cc: corbet@lwn.net, bob.picco@oracle.com, steven.sistare@oracle.com, pasha.tatashin@oracle.com, mike.kravetz@oracle.com, rob.gardner@oracle.com, mingo@kernel.org, nitin.m.gupta@oracle.com, anthony.yznaga@oracle.com, kirill.shutemov@linux.intel.com, tom.hromatka@oracle.com, allen.pais@oracle.com, tklauser@distanz.ch, shannon.nelson@oracle.com, vijay.ac.kumar@oracle.com, mhocko@suse.com, jack@suse.cz, punit.agrawal@arm.com, hughd@google.com, thomas.tai@oracle.com, ross.zwisler@linux.intel.com, dave.jiang@intel.com, willy@infradead.org, minchan@kernel.org, imbrenda@linux.vnet.ibm.com, aarcange@redhat.com, kstewart@linuxfoundation.org, pombredanne@nexb.com, tglx@linutronix.de, gregkh@linuxfoundation.org, nagarathnam.muthusamy@oracle.com, linux@roeck-us.net, jane.chu@oracle.com, dan.j.williams@intel.com, jglisse@redhat.com, ktkhai@virtuozzo.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, sparclinux@vger.kernel.org, Khalid Aziz References: From: Khalid Aziz Organization: Oracle Corp Message-ID: <84931753-9a84-8624-adb8-95bd05d87d56@oracle.com> Date: Mon, 5 Mar 2018 14:14:50 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8823 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=973 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1803050243 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1593031948178483523?= X-GMAIL-MSGID: =?utf-8?q?1594134191456715102?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 03/05/2018 12:22 PM, Dave Hansen wrote: > On 02/21/2018 09:15 AM, Khalid Aziz wrote: >> +#define arch_validate_prot(prot, addr) sparc_validate_prot(prot, addr) >> +static inline int sparc_validate_prot(unsigned long prot, unsigned long addr) >> +{ >> + if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_ADI)) >> + return 0; >> + if (prot & PROT_ADI) { >> + if (!adi_capable()) >> + return 0; >> + >> + if (addr) { >> + struct vm_area_struct *vma; >> + >> + vma = find_vma(current->mm, addr); >> + if (vma) { >> + /* ADI can not be enabled on PFN >> + * mapped pages >> + */ >> + if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)) >> + return 0; > > You don't hold mmap_sem here. How can this work? > Are you suggesting that vma returned by find_vma() could be split or merged underneath me if I do not hold mmap_sem and thus make the flag check invalid? If so, that is a good point. Thanks, Khalid