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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Proofpoint-ORIG-GUID: em8PIakncwmh402fP5ZAWm3RnN_iMc2F X-Authority-Analysis: v=2.4 cv=Z4Hc2nRA c=1 sm=1 tr=0 ts=6a4266cd cx=c_pps a=JbAStetqSzwMeJznSMzCyw==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=FelO9ux0wxsA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=gowsoOTTUOVcmtlkKump:22 a=VwQbUJbxAAAA:8 a=EUspDBNiAAAA:8 a=bQgpNS1FtnsdpSD-sWwA:9 a=QEXdDO2ut3YA:10 a=uxP6HrT_eTzRwkO_Te1X:22 X-Proofpoint-Spam-Info: AW1haW4tMjYwNjI5MDEwMyBTYWx0ZWRfX5XYg5tyBQWKL HTwNFXaqn7QKtuYqcT1HF2x742nnLggVSqfzfJgZKJ+BtkWidTfPVEVlItth30dVAxlohw83KsN bXFo0pVkVXGJupCKk3+ktASA7k7UeHU= X-Proofpoint-GUID: em8PIakncwmh402fP5ZAWm3RnN_iMc2F X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjI5MDEwMyBTYWx0ZWRfXwnobb0lfmhUM 3qL4aMhFhu0I6DfEuk4s5+xvcpMZn5iqu18cEokplnm0PRfNuAElotw9kDCB0gyoc4y7M1z7bzd osRtdM6EPNOMnKwvk9DFjlsp8yZ6nU49Xw7jTHOmTWSK0ORarO5i9VgZqmKOYL8DFzpfDGCv1IV jf/GpSt4W+4Tzv6IOXSIJ56c9y1Que2gmgDOQL6apAs5kv2zIsNq3jiKqwLe2iihPuQYU07LtjD BOfFYbiPREZx0AALNtNSsQTWv7fGvAiodzjiZovYClT8e9TISWmfgzAfggVHWyVwVjf0mHu+8Gz z6hCRtIUXCRp9OOrW9EKlneP2rKbVM3KRmwCMM5avvgnEFBErTvEltLkWnEugfsbhihzFglkaNz Iu3+Amc2h3c4Ooszc6Vq/+jsL0Zhj6wbbuXVtFAvrgaPVChSU44b+w3xVTg0xibsds0H49RSrIh Rt43h4saZK3riJ27qxA== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-29_03,2026-06-26_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 lowpriorityscore=0 priorityscore=1501 bulkscore=0 spamscore=0 impostorscore=0 phishscore=0 clxscore=1015 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2606290103 On 6/18/26 9:16 AM, Chunkai Deng wrote: > glink_smem_rx_peek() reads the RX FIFO payload after the caller has > determined data is available via glink_smem_rx_avail(), which reads the > remote-updated head index. A control dependency between the head read > and the subsequent payload read does not order the two loads, so the > CPU may speculatively read the FIFO before observing the head update > and consume stale data the remote has not yet published. > > Add rmb() in glink_smem_rx_peek() before the memcpy_fromio() so the > availability (head) read is ordered ahead of the FIFO payload read, > matching the consumer pattern in > Documentation/core-api/circular-buffers.rst. > > Fixes: caf989c350e8 ("rpmsg: glink: Introduce glink smem based transport") > Cc: stable@vger.kernel.org > Signed-off-by: Chunkai Deng > --- Reviewed-by: Konrad Dybcio Konrad