On 3/12/2025 4:42 PM, Rob Herring (Arm) wrote: > There's no need to check the property presence and length before calling > of_property_read_u8_array() as it will return an error if the property > is missing or the length is too small. The return errno doesn't matter > to the caller, so no change in behavior there. > > Change of_property_read_u8_array() to of_property_read_variable_u8_array() > as the former allows properties to be longer than the requested length. > Now the property has to be the exact length requested as the removed > check required. > > This part of a larger effort to remove DT functions like > of_get_property() and of_find_property() which return raw DT data > having no reference counting. > > Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx> > --- > drivers/net/wireless/ath/ath10k/core.c | 22 ++++++---------------- > 1 file changed, 6 insertions(+), 16 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c > index b3294287bce1..db7444af251d 100644 > --- a/drivers/net/wireless/ath/ath10k/core.c > +++ b/drivers/net/wireless/ath/ath10k/core.c > @@ -1889,7 +1889,7 @@ static int ath10k_download_cal_file(struct ath10k *ar, > static int ath10k_download_cal_dt(struct ath10k *ar, const char *dt_name) > { > struct device_node *node; > - int data_len; > + int data_len = ar->hw_params.cal_data_len; > void *data; > int ret; > > @@ -1900,28 +1900,18 @@ static int ath10k_download_cal_dt(struct ath10k *ar, const char *dt_name) > */ > return -ENOENT; > > - if (!of_get_property(node, dt_name, &data_len)) { > - /* The calibration data node is optional */ > - return -ENOENT; > - } note that there is one instance where .cal_data_len = 0 so i suggest that there still needs to be an early return here to avoid kmalloc(0): if (!data_len) return -ENOENT; > - > - if (data_len != ar->hw_params.cal_data_len) { > - ath10k_warn(ar, "invalid calibration data length in DT: %d\n", > - data_len); > - ret = -EMSGSIZE; > - goto out; > - } > - > data = kmalloc(data_len, GFP_KERNEL); > if (!data) { > ret = -ENOMEM; > goto out; > } > > - ret = of_property_read_u8_array(node, dt_name, data, data_len); > + ret = of_property_read_variable_u8_array(node, dt_name, data, data_len, data_len); > if (ret) { > - ath10k_warn(ar, "failed to read calibration data from DT: %d\n", > - ret); > + /* Don't warn if optional property not found */ > + if (ret != -EINVAL) > + ath10k_warn(ar, "failed to read calibration data from DT: %d\n", > + ret); > goto out_free; > } > this could made even cleaner using cleanup.h functionality (all of the gotos could disappear). perhaps I'll do that as a follow-up patch on top of your patch. /jeff