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Tue, 18 Aug 2026 12:01:31 +0000 (GMT) Received: from tuxmaker (unknown [9.87.85.9]) by smtpav06.fra02v.mail.ibm.com (Postfix) with ESMTPS; Tue, 18 Aug 2026 12:01:31 +0000 (GMT) Date: Tue, 18 Aug 2026 14:01:30 +0200 From: Alexander Gordeev To: Andrey Konovalov Cc: Gerald Schaefer , Heiko Carstens , Christian Borntraeger , Vasily Gorbik , Claudio Imbrenda , Andrey Ryabinin , linux-s390@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Subject: Re: [PATCH v7 3/4] mm/kasan: Introduce helpers for lazy MMU mode sanitizer Message-ID: <20260818120130.1411942A70-agordeev@linux.ibm.com> References: <52c9be0cf71a8896a5d76c148c38fb24a2005dd9.1786956464.git.agordeev@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODE4MDA4OCBTYWx0ZWRfX/HzJ7nnyCHrh +HaoG7Id6qPNfsSLkUn8mpVhPXOsqePWVGHOcVMdnZc71woPoeBm51360tzgkp6pAXAUkmsKfdw uySTXd818WHVCgQiDXvFNCL+sQKyINLqnpzF4En1gWktv+YUG8hOvwg3+qyuSpoEiPdUSfUjHy5 sVUMA5g6I0ktA4IXxQ/SJockakps4NfT2kGZkqekhp4rQS327gew3p3GltYmDT9HAYP3WccN4nf lW3+kHKC9OLej7j4SUzXSLWhHYHTAj6DI85bAimADWgotsdmfZdmdT1ad6tbRNh/5OTcKIQ4I53 4iC8dCbroiEFZaaY5vwu/7/n5x2FUnKJokVbBJnWPeZ2I5NKoxmfysQyNzsbJz/7yyGpIiFvLEF 5nRR0QluSHGgCq4jk5daT3oX9pRssJggUFa3GgQIOIF7nLtiqgIcmD2WFwdXSQAMonkNZvPBddA AfBuyIgIdoEp0+LpXfQ== X-Proofpoint-Spam-Info: AW1haW4tMjYwODE4MDA4OCBTYWx0ZWRfXxMSVUzPPppRN ief7nN+40tBCowkFDgNL4o/GB7pq7c2SdXf+jIMTMvFH7PEyZ0wkjsP0P9uBY0fYWrHJJmR51WA qSzR0/DJz/X8lToW9bcfQV0/KPJssgM= X-Authority-Analysis: v=2.4 cv=JKkLdcKb c=1 sm=1 tr=0 ts=6a8449a1 cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=kj9zAlcOel0A:10 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=Y2IxJ9c9Rs8Kov3niI8_:22 a=VwQbUJbxAAAA:8 a=7CQSdrXTAAAA:8 a=8Uvy48UusG5hzorP5EsA:9 a=CjuIK1q_8ugA:10 a=zZCYzV9kfG8A:10 a=a-qgeE7W1pNrGK8U0ZQC:22 X-Proofpoint-ORIG-GUID: N5GgORfBdGiu4Lb-ApmOs7EFDv6zGCAn X-Proofpoint-GUID: VKmHdYY6rFcIke9BaqPbB--R8GbSD7J7 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-18_01,2026-08-12_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 lowpriorityscore=0 clxscore=1015 adultscore=0 impostorscore=0 spamscore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608180088 On Tue, Aug 18, 2026 at 12:11:34AM +0200, Andrey Konovalov wrote: ... > Hi Alexander, > > Should all this be limited to only s390? The idea is to allow any architecture to opt-in. Once [1] is accepted this may look redundant, but I still see the benefit in having it. I only did not manage to circumvent the ugly __no_sanitize_address for ptep_get_lockless() to make it avoid "bogus" kasan complains when gup_fast walks a page table that entered the lazy mmu mode. 1. https://lore.kernel.org/linux-mm/20260806083926.1807279-1-usama.anjum@arm.com/ > Thanks!