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Tue, 25 Aug 2026 07:50:31 +0000 (GMT) Received: from li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com (unknown [9.111.94.220]) by smtpav01.fra02v.mail.ibm.com (Postfix) with ESMTPS; Tue, 25 Aug 2026 07:50:31 +0000 (GMT) Date: Tue, 25 Aug 2026 09:50:30 +0200 From: Alexander Gordeev To: Heiko Carstens Cc: Andrey Konovalov , Gerald Schaefer , 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: References: <52c9be0cf71a8896a5d76c148c38fb24a2005dd9.1786956464.git.agordeev@linux.ibm.com> <20260818120130.1411942A70-agordeev@linux.ibm.com> <20260824095635.11040Be5-hca@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-s390@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: <20260824095635.11040Be5-hca@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=TfimcxQh c=1 sm=1 tr=0 ts=6a8d494d cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=kj9zAlcOel0A:10 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=UUUDspzaHmeMqvLuHH4A:9 a=CjuIK1q_8ugA:10 a=zZCYzV9kfG8A:10 X-Proofpoint-Spam-Info: AW1haW4tMjYwODI1MDA2MyBTYWx0ZWRfX1UHCLV5+e1ku Bgn8RhOV7C6kM93dO+8ZojEFJxd3UxNobEmy2rwhytC1uQf9w9+9o88eWRIR3m+FXdMYpAxtc/g 3jIYLqLjXuVFEOeYLLkZkIF9hKjrvls= X-Proofpoint-GUID: cHEBOSUK2gjUGPKucThiW1yn6xPnJ6ye X-Proofpoint-ORIG-GUID: QUiBDcHGUMJNuhKLd6qzRIM5vSKsBumz X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODI1MDA2MyBTYWx0ZWRfX5XNKnD3AcB/l 60zzrpu3M/nJBAHn1S4j77pylmm2Xv3rLRsy8PoSsYbPmmJzM1P1hoRVSaPppyLrV6I3VRxtnvC Qyvez7nqN9ADdnyFMj//rnSfACuWt14MrGZ841V5Ao0xKjXk7wwEU4XOp+OfefjP2JHXFLJjwsw j8oz3tZ8APPuNMCeNElUo8uy0jUf9Fj0hlDq0Y6VZ9aeFuzGpDyqvuNDkPtBss1V0vx+b0sgItO CbrFZts6mH24N6J+a9Rix2nmdPnhPPLF/tF7t+165IpYGijcCQDHB674W9WnKyWASMV+DLFpKCy i7+mPGaV9neTj4e7cexQjKXoHQZg7blcC+XqkCU5DfyWUqLkrMin/pPimkZa7tJ8d6GadSXSjVs IhvJlzVRSWtqZ+z45I+OmfUL44AOZf/zVA+OO5R60eJ9aXoZn/QpbPVeC6Yo97F/P24fskG1lDD NsehB+v/fYx1i/CGJlw== 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=2026-08-25_01,2026-08-24_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 spamscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 lowpriorityscore=0 clxscore=1015 phishscore=0 impostorscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608250063 On Mon, Aug 24, 2026 at 11:56:35AM +0200, Heiko Carstens wrote: > On Tue, Aug 18, 2026 at 02:01:30PM +0200, Alexander Gordeev wrote: > > 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. > > What would be the benefit if [1] is accepted? Just another mechanism for verification, and pretty cheap one. I would dare to say [1] does not rule out an invalid access completely.