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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Proofpoint-Spam-Info: AW1haW4tMjYwNjI5MDEwMyBTYWx0ZWRfX1z2hnAHb/gYk pDO6wZknICpSUu+4AqUMtlq5Duv+g26uEwkapD7i1PL5IWjCPN22+EXL47gn65khltG9C+83Zbk 7MRvcyRrObdHHLrfhP0bz9JBCZA9FcU= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjI5MDEwMyBTYWx0ZWRfX++nJdju1ruw+ n0dkgEUUSkDGSZoYCl3PmiTkbtI2r7c5bVpPZbCo+BCBNOYOwrCVEaf6snuHPtaEH5td4JelPTx 7GTpZknZdT9ETqLvV+yL8t2fpvRP8JLwfUvwd2HIm9HQ3zyDYFiF37pBibak14Nqe3JC/5DPbc+ wncr4mz3bu86rUBYE+WfvHjQUa8L6rnYMw53DIgralFOvP9XuWMsrehEe6+f/knpluYePRAinl+ j96y7QEaZZJohbn+6XlAObRHCffnN4OQM634evbaHK0zMfWaqPMa0kc25ORqG/3w3PBHyy7kqZp 9u38QSyCJw/df3mJ1vTp1tC5fyQd65JeJ0Trp7deUls9ApAbxX68kbGshcx9jflKXD2OFvDanhg wWCYlaCILBWD+SaMfV/4royv0TBwTgTLyLoRl9GkEL4zkLeG/o+UUZJ5UCmVLUfBcQsAxVyolQm uZ+toMKRo0krZhbDdcA== X-Proofpoint-GUID: 6TK7AfQyXuHj_czGn81ImqxsrTEgawoP X-Authority-Analysis: v=2.4 cv=cefiaHDM 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=YMgV9FUhrdKAYTUUvYB2:22 a=VwQbUJbxAAAA:8 a=EUspDBNiAAAA:8 a=bQgpNS1FtnsdpSD-sWwA:9 a=QEXdDO2ut3YA:10 a=uxP6HrT_eTzRwkO_Te1X:22 X-Proofpoint-ORIG-GUID: 6TK7AfQyXuHj_czGn81ImqxsrTEgawoP 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 spamscore=0 impostorscore=0 lowpriorityscore=0 malwarescore=0 bulkscore=0 suspectscore=0 clxscore=1015 priorityscore=1501 adultscore=0 phishscore=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