On Thu, Jan 10, 2019 at 01:43:01PM -0600, Li Yang wrote: > On Sat, Dec 22, 2018 at 2:02 AM Nicholas Mc Guire <der.h...@hofr.at> wrote: > > > > On Fri, Dec 21, 2018 at 08:29:56PM -0600, Scott Wood wrote: > > > On Fri, 2018-12-07 at 09:22 +0100, Nicholas Mc Guire wrote: > > > > devm_kstrdup() may return NULL if internal allocation failed, but > > > > as machine is from the device tree, and thus RO, devm_kstrdup_const() > > > > can be used here, which will only copy the reference. > > > > > > Is it really going to only copy the reference? That would require that > > > is_kernel_rodata(machine) be true, which it shouldn't be since it's not > > > part > > > of the kernel image. > > > > > I had tried to figure out what is RO and what not but was not > > able to determine that - from the discussion it seemed that the > > assumption of RO is correct though I did not ask if it would > > satisfy is_kernel_rodata() so that explains the incorrect assertion. > > see https://lkml.org/lkml/2018/12/6/42 > > So then the only option is to check the return and cleanup > > on allocation failure as the orriginal patch proposed. > > Thanks for the good discussion. I will drop the previous patch. But > would it also be good to just have "soc_dev_attr.machine = machine" > directly? > I think that the intent is to switch to managed devm API so that the cleanup is handled properly currently you would get "machine" from of_property_read_string_index -> of_property_read_string_helper -> of_find_property which does not do any allocation - so there would actually not be anything to cleanup here - don´t see why your solution would not be suitable given the current API. the only advantage of the devm_kstrdup() is that underlying APIs internal changes would have no effect.
thx! hofrat
