On Wed, 25 Mar 2026 23:22:04 +0900
Masami Hiramatsu (Google) <[email protected]> wrote:
> > + /*
> > + * Keys that do not match any early_param() handler are silently
> > + * ignored — do_early_param() always returns 0.
> > + */
> > + xbc_node_for_each_key_value(root, knode, val) {
>
> [sashiko comment]
> | Does this loop handle array values correctly?
> | xbc_node_for_each_key_value() only assigns the first value of an array to
> | the val pointer before advancing to the next key. It does not iterate over
> | the child nodes of the array.
> | If the bootconfig contains a multi-value key like
> | kernel.console = "ttyS0", "tty0", will the subsequent values in the array
> | be silently dropped instead of passed to the early_param handlers?
>
> Also, good catch :) we need to use xbc_node_for_each_array_value()
> for inner loop.
FYI, xbc_snprint_cmdline() translates the arraied parameter as
multiple parameters. For example,
foo = bar, buz;
will be converted to
foo=bar foo=buz
Thus, I think we should do the same thing below;
>
> > + if (xbc_node_compose_key_after(root, knode, xbc_namebuf,
> > XBC_KEYLEN_MAX) < 0)
> > + continue;
> > +
> > + /*
> > + * We need to copy const char *val to a char pointer,
> > + * which is what do_early_param() need, given it might
> > + * call strsep(), strtok() later.
> > + */
> > + ret = strscpy(val_buf, val, sizeof(val_buf));
> > + if (ret < 0) {
> > + pr_warn("ignoring bootconfig value '%s', too long\n",
> > + xbc_namebuf);
> > + continue;
> > + }
> > + do_early_param(xbc_namebuf, val_buf, NULL, NULL);
So instead of this;
xbc_array_for_each_value(vnode, val) {
do_early_param(xbc_namebuf, val, NULL, NULL);
}
Maybe it is a good timing to recondier unifying kernel cmdline and bootconfig
from API viewpoint.
Thanks,
--
Masami Hiramatsu (Google) <[email protected]>
