There are two pachs which will restore the syscall registers (x0 - x7) separately: the hardirq trace code and the context tracking code.
This patch makes the code to restore the syscall registers only once. Signed-off-by: Huang Shijie <[email protected]> --- arch/arm64/kernel/entry.S | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 102fd8b..98d8dd1 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -46,12 +46,9 @@ * Context tracking subsystem. Used to instrument transitions * between user and kernel mode. */ - .macro ct_user_exit, syscall = 0 + .macro ct_user_exit #ifdef CONFIG_CONTEXT_TRACKING bl context_tracking_user_exit - .if \syscall == 1 - restore_syscall_regs - .endif #endif .endm @@ -729,12 +726,12 @@ el0_svc: uxtw scno, w26 // syscall number in w8 mov sc_nr, #__NR_syscalls el0_svc_naked: // compat entry point -#ifdef CONFIG_TRACE_IRQFLAGS - restore_syscall_regs -#endif stp x19, scno, [sp, #S_ORIG_X0] // save the original x0 and syscall number enable_dbg_and_irq - ct_user_exit 1 + ct_user_exit +#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING) + restore_syscall_regs +#endif ldr x16, [tsk, #TI_FLAGS] // check for syscall hooks tst x16, #_TIF_SYSCALL_WORK -- 2.5.5
