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Wythe" , "David S. Miller" , Dust Li , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Wenjia Zhang Cc: Mahanta Jambigi , Simon Horman , Tony Lu , Wen Gu , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, netdev@vger.kernel.org, oliver.yang@linux.alibaba.com, pasic@linux.ibm.com References: <20260407124337.88128-1-alibuda@linux.alibaba.com> Content-Language: en-US From: Sidraya Jayagond In-Reply-To: <20260407124337.88128-1-alibuda@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDE2MDEwNyBTYWx0ZWRfX8x0eGXZv6PQ2 N8zDpzcRs5IWDJR9CM9coVhXpeUsN/3YrWzFt4hpgGWHKQnjPWoS8EOx4YzFFRlJ9zGCyG51dRE xPdim5Ndeox66cKgvd/7837Yy8sehauk0j3jG6rvEU0VLJq2KeXX2qsT2HB921trcPlPQkc49hR Qe+VhKQjQgK2gRh9ShfnCJ2YZGAtBiBZbAnU12F1S8tUu48lyyQ/Ep8VRV+KIKZyvG1DdU8ZUDq RLeHn3WxVAiJPGby4xJCvToJll80YpOuvZSAT3KbKG2gYdh/mzApUPAW4aLT6f4ocj9anI/Vhj3 lk1ciJ3NuaUmqfEuopDc+X1mMGueOwmKDJq5fgizhTAUl3f8YcycK4M/FywelsXcymtkUwTLBAW GZZk3onmRd7ziijtGdeNOOsFlPR9QA8AU/+mewAhxpfOGRGH/R0l/eN05e+fwlFThEfwjK1wi2a OMnHwAPhU8J0rALryxA== X-Proofpoint-ORIG-GUID: ssQXe45jGByViQJvwAu5KWLlSx6QYBKf X-Proofpoint-GUID: f4xXQOKTW5UaryjFMYNdUl6sVneEUs6x X-Authority-Analysis: v=2.4 cv=fYidDUQF c=1 sm=1 tr=0 ts=69e0cb07 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=U7nrCbtTmkRpXpFmAIza:22 a=VwQbUJbxAAAA:8 a=SRrdq9N9AAAA:8 a=VnNF1IyMAAAA:8 a=qxvEQBEN2lSPpFVz31sA:9 a=QEXdDO2ut3YA:10 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=2026-04-16_03,2026-04-13_04,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 impostorscore=0 clxscore=1011 malwarescore=0 phishscore=0 bulkscore=0 priorityscore=1501 spamscore=0 suspectscore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604070000 definitions=main-2604160107 On 07/04/26 6:13 pm, D. Wythe wrote: > The alloc_pages() cannot satisfy requests exceeding MAX_PAGE_ORDER, > and attempting such allocations will lead to guaranteed failures > and potential kernel warnings. > > For SMCR_PHYS_CONT_BUFS, cap the allocation order to MAX_PAGE_ORDER. > This ensures the attempts to allocate the largest possible physically > contiguous chunk succeed, instead of failing with an invalid order. > This also avoids redundant "try-fail-degrade" cycles in > __smc_buf_create(). > > For SMCR_MIXED_BUFS, no cap is needed: if the order exceeds > MAX_PAGE_ORDER, alloc_pages() will silently fail (__GFP_NOWARN) > and automatically fall back to virtual memory. > > Signed-off-by: D. Wythe > Reviewed-by: Dust Li > --- > Changes v1 -> v2: > https://lore.kernel.org/netdev/20260312082154.36971-1-alibuda@linux.alibaba.com/ > > - Move the bufsize cap from smcr_new_buf_create() up to > __smc_buf_create(), which is simpler and avoids touching > the allocation logic itself. > --- > net/smc/smc_core.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c > index e2d083daeb7e..cdd881746e21 100644 > --- a/net/smc/smc_core.c > +++ b/net/smc/smc_core.c > @@ -2440,6 +2440,10 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb) > /* use socket send buffer size (w/o overhead) as start value */ > bufsize = smc->sk.sk_sndbuf / 2; > > + /* limit bufsize for physically contiguous buffers */ > + if (!is_smcd && lgr->buf_type == SMCR_PHYS_CONT_BUFS) > + bufsize = min_t(int, bufsize, (PAGE_SIZE << MAX_PAGE_ORDER)); > + > for (bufsize_comp = smc_compress_bufsize(bufsize, is_smcd, is_rmb); > bufsize_comp >= 0; bufsize_comp--) { > if (is_rmb) { Code changes looks good to me. Thanks Reviewed-by: Sidraya Jayagond