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Tsirkin" , Jason Wang , Xuan Zhuo , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , Andrew Morton , Jonathan Corbet , Mario Casquero References: <20241014144622.876731-1-david@redhat.com> <20241014144622.876731-6-david@redhat.com> <20241014184824.10447-F-hca@linux.ibm.com> <20241015083750.7641-D-hca@linux.ibm.com> Content-Language: en-US From: Christian Borntraeger In-Reply-To: <20241015083750.7641-D-hca@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: MZ1yrbyezdS4zll8wFGufHjjP4N0smer X-Proofpoint-ORIG-GUID: 37ZgR9RiC9b_Gof1v4vav0KFZsJWLwy9 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=853 clxscore=1011 suspectscore=0 lowpriorityscore=0 mlxscore=0 impostorscore=0 spamscore=0 phishscore=0 adultscore=0 priorityscore=1501 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410210043 Am 15.10.24 um 10:37 schrieb Heiko Carstens: > On Mon, Oct 14, 2024 at 09:16:45PM +0200, David Hildenbrand wrote: >> On 14.10.24 20:48, Heiko Carstens wrote: >>> On Mon, Oct 14, 2024 at 04:46:17PM +0200, David Hildenbrand wrote: >>>> to dump. Based on this, support for dumping virtio-mem memory can be >>> Hm.. who will add this support? This looks like a showstopper to me. >> >> The cover letter is clearer on that: "One remaining work item is kdump >> support for virtio-mem memory. This will be sent out separately once initial >> support landed." >> >> I had a prototype, but need to spend some time to clean it up -- or find >> someone to hand it over to clean it up. >> >> I have to chose wisely what I work on nowadays, and cannot spend that time >> if the basic support won't get ACKed. >> >>> Who is supposed to debug crash dumps where memory parts are missing? >> >> For many production use cases it certainly needs to exist. >> >> But note that virtio-mem can be used with ZONE_MOVABLE, in which case mostly >> only user data (e.g., pagecache,anon) ends up on hotplugged memory, that >> would get excluded from makedumpfile in the default configs either way. >> >> It's not uncommon to let kdump support be added later (e.g., AMD SNP >> variants). > > I'll leave it up to kvm folks to decide if we need kdump support from > the beginning or if we are good with the current implementation. If David confirms that he has a plan for this, I am fine with a staged approach for upstream.