[patch V5 01/12] ARM: uaccess: Implement missing __get_user_asm_dword()
Mathieu Desnoyers
mathieu.desnoyers at efficios.com
Wed Oct 29 00:35:03 AEDT 2025
On 2025-10-27 04:43, Thomas Gleixner wrote:
> When CONFIG_CPU_SPECTRE=n then get_user() is missing the 8 byte ASM variant
> for no real good reason. This prevents using get_user(u64) in generic code.
>
> Implement it as a sequence of two 4-byte reads with LE/BE awareness and
> make the unsigned long (or long long) type for the intermediate variable to
> read into dependend on the the target type.
>
> The __long_type() macro and idea was lifted from PowerPC. Thanks to
> Christophe for pointing it out.
[...]
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
More information about the Linuxppc-dev
mailing list