[PATCH v6 09/20] arm64:ilp32: share HWCAP between LP64 and ILP32

On Thursday 17 December 2015 10:54:47 Catalin Marinas wrote:

quoted

quoted

IIUC, we may have a problem with this. elf_hwcap is 64-bit long while
elf_info[n] is 32-bit (Elf32_Addr), so we truncate AT_HWCAP if we ever
go beyond bit 31. The above may need to look something like:

#define COMPAT_ELF_HWCAP        \
        (is_a32_compat_task()   \
         ? compat_elf_hwcap     \
         : (u32)elf_hwcap)

#define COMPAT_ELF_HWCAP2       \
        (is_a32_compat_task()   \
         ? compat_elf_hwcap2    \
         : (u32)(elf_hwcap >> 32))

Yes, interesting find.

BTW, we need to make sure this series (primarily the ABI) is big-endian
safe. I know it is not targeted at this initially but given that the
reason for doing it is legacy networking code, I wouldn't be surprised
if someone asks for BE at some point in the future.

Yes, I'm sure that will be needed.

	Arnd