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Peter Anvin" , Eric Biederman , kexec@lists.infradead.org, Pratyush Yadav , Jason Gunthorpe , Pasha Tatashin , David Rientjes Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 0054D20003 X-Rspamd-Server: rspam03 X-Stat-Signature: 3wg7obeccrn4pygi83m81go7c363z9gz X-HE-Tag: 1741660063-450672 X-HE-Meta: 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 1ZLZUa12 GsU6hWIkJgIlwWwbFktA3S0Nd3Qb2/dlpYGz4ZS8nvqKMNQFPNvXOUW6aAmDGRJBmLmnuBMMguqnnehqVzgTGIOEntuu0UiJZat3wEX/X6lyth5zPdUC67HIrY16fG9MPGPmQufvcMsZ4jAWl8h2DToot4kukOOwwwe0+n0XvCj/pubgrR+X19JZBBn9i9WYy9INEnhIcY4uXSFzWWGL+A6QRWRZXTZrj/U0Nd+/DF04Qlsrt86bFf0gaZPeJ42f9b6tXvJPHCgEW36BsmjMzwnuAweKZIIag0YhroTP7hvN3UzwQCJzLcVslccrvOc/RX1z3wBHe7xIjZ1hYRblv9n8U5qp7W4IMNnbHAMCmYfnwMMBW8+5msiOPKT3uJ8vrt9+nUcmR24bJxt2Y+f53Jf4frPO2Cxi9RXU3m63t7GXTKC1gDHZQwNI0DaI524QkDpQNA/qohHRVxdY= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Andrey, On Mon, Mar 10, 2025 at 5:04=E2=80=AFAM Andrey Ryabinin wrote: > Each driver/subsystem has to solve this problem in their own way. > Also if we use fdt properties for individual fields, that might be wa= stefull > in terms of used memory, as these properties use strings as keys. > > While with KSTATE solves the same problem in more elegant way, with th= is: > struct kstate_description a_state =3D { > .name =3D "a_struct", > .version_id =3D 1, > .id =3D KSTATE_TEST_ID, > .state_list =3D LIST_HEAD_INIT(test_state.state_list), > .fields =3D (const struct kstate_field[]) { > KSTATE_BASE_TYPE(i, struct a, int), > KSTATE_BASE_TYPE(s, struct a, char [10]), > KSTATE_POINTER(p_ulong, struct a), > KSTATE_PAGE(page, struct a), > KSTATE_END_OF_LIST() > }, > }; Hmm, this still requires manual efforts to implement this, so potentially a lot of work given how many drivers we have in-tree. And those KSTATE_* stuffs look a lot similar to BTF: https://docs.kernel.org/bpf/btf.html So, any possibility to reuse BTF here? Note, BTF is automatically generated by pahole, no manual effort is required. Regards, Cong Wang