From: Peter Bergner <bergner@linux.ibm.com> Changes from v1: - Add Acked-by lines. The powerpc toolchain keeps a copy of the HWCAP bit masks in our TCB for fast access by the __builtin_cpu_supports built-in function. The TCB space for the HWCAP entries - which are created in pairs - is an ABI extension, so waiting to create the space for HWCAP3 and HWCAP4 until we need them is problematical. Define AT_HWCAP3 and AT_HWCAP4 in the generic uapi header so they can be used in glibc to reserve space in the powerpc TCB for their future use. I scanned through the Linux and GLIBC source codes looking for unused AT_* values and 29 and 30 did not seem to be used, so they are what I went with. This has received Acked-by's from both GLIBC and Linux kernel developers and no reservations or Nacks from anyone. Arnd, we seem to have consensus on the patch below. Is this something you could take and apply to your tree? Peter Signed-off-by: Peter Bergner <bergner@linux.ibm.com> Acked-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Acked-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Szabolcs Nagy <szabolcs.nagy@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Commit: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/a406b535-dc55-4856-8ae9-5a063644a1af@linux.ibm.com Signed-off-by: Hongye Lin <linhongye@h-partners.com> Signed-off-by: Qi Xi <xiqi2@huawei.com> --- include/uapi/linux/auxvec.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/uapi/linux/auxvec.h b/include/uapi/linux/auxvec.h index 6991c4b8ab18..cc61cb9b3e9a 100644 --- a/include/uapi/linux/auxvec.h +++ b/include/uapi/linux/auxvec.h @@ -32,6 +32,8 @@ #define AT_HWCAP2 26 /* extension of AT_HWCAP */ #define AT_RSEQ_FEATURE_SIZE 27 /* rseq supported feature size */ #define AT_RSEQ_ALIGN 28 /* rseq allocation alignment */ +#define AT_HWCAP3 29 /* extension of AT_HWCAP */ +#define AT_HWCAP4 30 /* extension of AT_HWCAP */ #define AT_EXECFN 31 /* filename of program */ -- 2.33.0