There are a total of system calls (aside from ioctl) that pass a time_t or derived data structure as an argument, and in order to extend time_t to 64-bit, we have to replace them with new system calls and keep providing backwards compatibility. To avoid adding completely new and untested code for this purpose, we introduce a new CONFIG_COMPAT_TIME symbol that is always set on 64-bit architectures with 32-bit compat mode, as well as all 32-bit architectures that have been extended to provide the new system calls. After this is done for all architectures, the CONFIG_COMPAT_TIME symbol can be made a user-selected option, to enable users to build a kernel that only provides y2038-safe system calls. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- arch/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index a65eafb24997..630d3d289569 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -545,4 +545,15 @@ config OLD_SIGACTION config COMPAT_OLD_SIGACTION bool +config ARCH_HAS_COMPAT_TIME + def_bool COMPAT + +config COMPAT_TIME + def_bool ARCH_HAS_COMPAT_TIME + help + This should be selected by all architectures that need to support + system calls with a 32-bit time_t. Traditionally, this has been + used on all 32-bit architectures, and needs to be supported on + 64-bit architectures as part of compat syscall handling. + source "kernel/gcov/Kconfig" -- 2.1.0.rc2 -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
