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R. Silva" Cc: Thorsten Blum , Tony Krowiak , Jason Herne , Harald Freudenberger , Holger Dengler , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , linux-hardening@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Halil Pasic Subject: Re: [PATCH] s390/vfio-ap: Replace one-element array with flexible array member Message-ID: <20250130114615.6f591882.pasic@linux.ibm.com> In-Reply-To: <85863d7a-2d8b-4c1b-b76a-e2f40834a7a8@embeddedor.com> References: <20250116131859.105756-2-thorsten.blum@linux.dev> <20250129213826.291cfe12.pasic@linux.ibm.com> <85863d7a-2d8b-4c1b-b76a-e2f40834a7a8@embeddedor.com> Organization: IBM X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) 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-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: q9NxGqcZI12C94KXtUoH1A5QT5ao1ZLb X-Proofpoint-ORIG-GUID: q9NxGqcZI12C94KXtUoH1A5QT5ao1ZLb X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-01-30_06,2025-01-30_01,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxlogscore=635 lowpriorityscore=0 impostorscore=0 phishscore=0 adultscore=0 priorityscore=1501 clxscore=1011 mlxscore=0 malwarescore=0 spamscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2501300081 On Thu, 30 Jan 2025 10:30:30 +1030 "Gustavo A. R. Silva" wrote: > On 30/01/25 07:08, Halil Pasic wrote: > > On Thu, 16 Jan 2025 14:18:59 +0100 > > Thorsten Blum wrote: > > > >> Replace the deprecated one-element array with a modern flexible array > >> member in the struct ap_matrix_dev. > >> > > > > I'm not sure I understand the value of this. What we have here is not > > a flexible array but a one element array. Something that in the generic > > case could be many but particularly for vfio-ap is always one. > > You are correct. Only fake flexible arrays should be transformed into > C99 flex-array members [1]. > > Thanks > -Gustavo > > [1] https://lwn.net/Articles/908817/ > Thanks! Alex, what do we do with this then? I think you picked it up yesterday late. And I think, it might make sense to make this look less like a fake flex-array...