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charset=us-ascii Content-Disposition: inline In-Reply-To: <3b901f9d-dbfa-4f93-a8d2-3e89bd9783c9@kernel.org> X-Authority-Analysis: v=2.4 cv=IrITsb/g c=1 sm=1 tr=0 ts=68e39417 cx=c_pps a=MTSHoo12Qbhz2p7MsH1ifg==:117 a=fChuTYTh2wq5r3m49p7fHw==:17 a=kj9zAlcOel0A:10 a=x6icFKpwvdMA:10 a=VwQbUJbxAAAA:8 a=COk6AnOGAAAA:8 a=kM1oLTEIhtBy5IrTauIA:9 a=CjuIK1q_8ugA:10 a=GvdueXVYPmCkWapjIL-Q:22 a=TjNXssC_j7lpFel5tvFf:22 X-Proofpoint-GUID: kv4MdwGD-E6F47UJqJY_rvqk8ZTnGqKP X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMDA0MDAyOSBTYWx0ZWRfX0LDYY1oOA7Es 1QbYDtTQwact9NYR/k9f5jqFKHqrhBWs56Oblwj9CYi1HiptXXa2UYVJ0VqiA0b2NkwcA4sBamV QMC38eGiPoUdY3U1G3tHdZWWFQkSG7+xTd90pVp2rvul71sAZjI73sPf7pLUWKEC+VeGs60ri2Q aMAp8Aq2cF+spEoBbMmiYFUkyoe7YzfGAJ1sUbqBKjbGrmXkcrAKL3XEBUnCrWtJbx0X+y97Sxw 8mpVor+zzW+Uot0b4y6vdceB51H7wWjP6PkAkp6I7vg7cQnhk29K3EVn2GFK4KvSXJbQqJsBoLh VwWSWb+tRgNC9vLC+ODKZGkuzHibJIPiZj4gz4NlPmt8YK7lSkwDPccssiQ5zHM7r51EJ7RWy4n RHDAZPDMjFlF7THUTPDaEQRMurc+rw== X-Proofpoint-ORIG-GUID: kv4MdwGD-E6F47UJqJY_rvqk8ZTnGqKP X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-10-06_03,2025-10-02_03,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 priorityscore=1501 bulkscore=0 clxscore=1015 malwarescore=0 spamscore=0 phishscore=0 impostorscore=0 lowpriorityscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2509150000 definitions=main-2510040029 On Mon, Oct 06, 2025 at 05:56:42PM +0900, Krzysztof Kozlowski wrote: > On 06/10/2025 16:37, Hrishabh Rajput via B4 Relay wrote: > > + > > +static int __init gunyah_wdt_init(void) > > +{ > > + struct arm_smccc_res res; > > + struct watchdog_device *wdd; > > + struct device_node *np; > > + int ret; > > + > > + np = of_find_compatible_node(NULL, NULL, "qcom,kpss-wdt"); > > + if (np) { > > + of_node_put(np); > > + return -ENODEV; > > + } > > + > > + np = of_find_compatible_node(NULL, NULL, "arm,sbsa-gwdt"); > > + if (np) { > > + of_node_put(np); > > + return -ENODEV; > > + } > > + > > + ret = gunyah_wdt_call(GUNYAH_WDT_STATUS, 0, 0, &res); > > + if (ret) > > + return -ENODEV; > > No, your hypervisor driver (which you have) should start the module via > adding platform/aux/something devices. Now you are running this on every > machine, which is clearly wrong... > This is a good point. Thanks for bringing it up. We don't have a hypervisor glue driver (yet!) that can add an aux device. Based on v1 feedback, we would like to be a standalone module that can self discover gunyah hypercall interface. Currently this driver depends on ARCH_QCOM || COMPILE_TEST. So, technically this can be built and loaded on all non-Qualcomm machines. We can make the STATUS SMCC before looking for the other watchdog devices and fail early. Our Gunyah glue driver [1] do make SMCC call to establish that we are actually a guest under Gunyah. Since our intention here is to support watchdog on as many as platform as possible, it is better not to tie this with glue driver and make it a stand alone and self discovery module. If this is not an acceptable solution (Please let us know), we can find other ways to limit it to only work on Qualcomm machines. For ex: Socinfo platform device is added from SMEM driver which make it only probed on Qualcomm machines. We can look into this. Thanks, Pavan [1] https://lore.kernel.org/all/20240222-gunyah-v17-4-1e9da6763d38@quicinc.com/