On Mon, Jul 13, 2026 at 11:54:22AM +0800, Jinjie Ruan wrote: > Currently, only x86 genuinely implements and supports Syscall User > Dispatch (SUD). Multiple architectures provide a stub > arch_syscall_is_vdso_sigreturn() returning 'false' simply to satisfy > GENERIC_ENTRY compilation, which creates a false impression of feature > support. > > Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH to decouple this mechanism > from GENERIC_ENTRY. Select it exclusively on x86 and remove the redundant > stub functions from other architectures. > > Link: > https://lore.kernel.org/linux-arm-kernel/[email protected]/ > Cc: Thomas Gleixner <[email protected]> > Cc: Mark Rutland <[email protected]> > Cc: Gregory Price <[email protected]> > Cc: Ada Couprie Diaz <[email protected]> > Cc: Thomas Weißschuh <[email protected]> > Suggested-by: Mark Rutland <[email protected]> > Signed-off-by: Jinjie Ruan <[email protected]>
Reviewed-by: Thomas Weißschuh <[email protected]> > --- > v1 -> RESEND > - Define missing ARCH_SUPPORTS_SYSCALL_USER_DISPATCH. If code is changed it is not a resend. Instead it should have been v2. > --- > arch/Kconfig | 4 ++++ > arch/loongarch/include/asm/syscall.h | 6 ------ > arch/powerpc/include/asm/syscall.h | 5 ----- > arch/riscv/include/asm/syscall.h | 5 ----- > arch/s390/include/asm/syscall.h | 5 ----- > arch/x86/Kconfig | 1 + > 6 files changed, 5 insertions(+), 21 deletions(-) (...)
