Thank you very much for your reply. On 05/09/2023 15:05, krzysztof.kozlowski@xxxxxxxxxx wrote: > On 05/09/2023 04:46, wangweidong.a@xxxxxxxxxx wrote: >>> Even though it does not look like from the diff, the property is not >>> actually used by the driver, because once set, it is read only in loops >>> depending on ddt_num (prof_hdr->ddt_num, cfg_hdr->ddt_num). The >>> variable ddt_num is never set and is always 0, so the loops do not have >>> any iteration. Dropping sound-channel and ddt_num-related loops allows >>> to drop empty functions which in turn drop quite a lot of code. This >>> entire code was not possible to execute. >> >> The ddt_num variable is not always 0, this variable is defined >> in the configuration file. The "prof_hdr" variable is assigned by >> the "cfg_hdr" variable. The "cfg_hdr" variable is assigned by "aw_cfg" >> aw_cfg is the data obtained through request_firmware.The specific >> process is as follows: >> >> request_firmware ---> cont->data ---> aw_cfg->data --> cfg_hdr --> prof_hdr > Hm. So you load user-space provided file and assign it directly, without > any validation (aw88395_dev_load_acf_check() checks only for magic), to > a kernel structure. Sounds bullet-proof. Why using known kernel > interfaces, better to implement some conf-file-parsing. Could you please tell me what known kernel interfaces can be used to parse files? Thank you very much Best regards, Weidong Wang
