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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Frank van der Linden , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260331113724.2080833-1-songmuchun@bytedance.com> <17246161-f314-45da-933a-770231ef2a49@kernel.org> <2183487D-0CED-4BEF-84D7-4439F3386584@linux.dev> <3ab0e5dd-cd3d-4f78-a7ee-01051f200b36@linux.ibm.com> <877d3988-57f3-4f87-8836-85aad5454879@kernel.org> Content-Language: en-US From: Donet Tom In-Reply-To: <877d3988-57f3-4f87-8836-85aad5454879@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=Fdo6BZ+6 c=1 sm=1 tr=0 ts=69ce5d1e cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=6ZReSu3Cd-7Xrk7Zi6IA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: iACiDCSOiDC-uueVeMYONtY9kaR5_I07 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDAyMDEwNiBTYWx0ZWRfX1maWR8aeei07 0FjVprD2oNKWJAXqytQADe6pQ/Ng4xKzYiX+mx87s6p2qZoz3Oz7SLFBabW1Ww5yKOWdYMVsHGN LR2So2YFB/3cwGKhu+h099A0Orqy/hxHzmy9vQuu7CxdQonGSJIa6ENpj1yAzP0/75SlW9UuYFb rjisW+++c0kPJzinMluoe0gdcdUAomepQv0oOTocQ+nC11IlvatWug+cw0/72x5leO/fWt+kueZ 6JIaV/mY/YynM8HJSk+6HgQKA9xjDpVazh0cKZAmd+fdNru/iLvQ/P4wmCucFaIR4MM0/u0t0uv zmavFUVz12oTPmNy9Lb9IkOkjthZ26rODYEVkkOwxSAiViqYcWz+rvJlxbFbV/24/aARjQaJCzz j8//h1onbqvMW4+OP2Dhf2lpXfF2bauVBjlt1Ms3NN5VMkpIZbFnqpxHe2qroGN1hdCeeBXcJpv vrTujrPj804LvxeyEew== X-Proofpoint-GUID: SnRke1UDQq_oxRThhDZTJI4cx9auW6Vz X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-02_01,2026-04-02_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 clxscore=1015 bulkscore=0 suspectscore=0 priorityscore=1501 adultscore=0 malwarescore=0 phishscore=0 spamscore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2604020106 On 4/2/26 1:26 PM, David Hildenbrand (Arm) wrote: > On 4/2/26 09:37, Donet Tom wrote: >> On 4/1/26 12:55 PM, David Hildenbrand (Arm) wrote: >>> On 4/1/26 04:41, Muchun Song wrote: >>>> Thanks. >>>> >>>> It's truly a coincidence — I also have a piece of code locally >>>> that does something similar. Since allocation failure would also >>>> affect subsequent startup processes, I simply made it panic when >>>> allocation fails. >>> Don't use BUG_ON, use actual panic(). :) >> >> Apologies if I’m missing something, but would it make sense to check the >> section validity in memmap_init() instead of panicking? Is there a >> reason this is avoided? > Not sure I understand your question, but trying to handle memmap > allocations during early boot should be removed. If that ever happens > something is fundamentally flawed. Thank you for the clarification—I understand now. -Donet >