Check return code of syscall_trace_enter(), and skip syscall if -1. Return code will be left at what had been set by ptrace or seccomp (in regs->d0). No regression seen in testing with strace on ARAnyM. Signed-off-by: Michael Schmitz <schmitzmic@xxxxxxxxx> -- Changes from v12: - prevent overwriting the syscall return value after change by ptrace or seccomp on 68020+ Changes from v7: Al Viro: - split return code checks from switch to syscall_trace_enter() Changes from v6: Geert Uytterhoeven: - add syscall_trace_enter() return code check for 68000 and coldfire Changes from v5: - add comment to explain optimization Changes from v4: Andreas Schwab: - optimize return code test (addql #1,%d0 for cmpil #-1,%d0) - spelling fix in commit message Changes from v3: - change syscall_trace_enter return code test from !=0 to ==-1 --- arch/m68k/68000/entry.S | 2 ++ arch/m68k/coldfire/entry.S | 2 ++ arch/m68k/kernel/entry.S | 3 +++ 3 files changed, 7 insertions(+) diff --git a/arch/m68k/68000/entry.S b/arch/m68k/68000/entry.S index 997b54933015..7d63e2f1555a 100644 --- a/arch/m68k/68000/entry.S +++ b/arch/m68k/68000/entry.S @@ -45,6 +45,8 @@ do_trace: jbsr syscall_trace_enter RESTORE_SWITCH_STACK addql #4,%sp + addql #1,%d0 + jeq ret_from_exception movel %sp@(PT_OFF_ORIG_D0),%d1 movel #-ENOSYS,%d0 cmpl #NR_syscalls,%d1 diff --git a/arch/m68k/coldfire/entry.S b/arch/m68k/coldfire/entry.S index 9f337c70243a..35104c5417ff 100644 --- a/arch/m68k/coldfire/entry.S +++ b/arch/m68k/coldfire/entry.S @@ -90,6 +90,8 @@ ENTRY(system_call) jbsr syscall_trace_enter RESTORE_SWITCH_STACK addql #4,%sp + addql #1,%d0 + jeq ret_from_exception movel %d3,%a0 jbsr %a0@ movel %d0,%sp@(PT_OFF_D0) /* save the return value */ diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S index 18f278bdbd21..42879e6eb651 100644 --- a/arch/m68k/kernel/entry.S +++ b/arch/m68k/kernel/entry.S @@ -184,9 +184,12 @@ do_trace_entry: jbsr syscall_trace_enter RESTORE_SWITCH_STACK addql #4,%sp + addql #1,%d0 | optimization for cmpil #-1,%d0 + jeq ret_from_syscall movel %sp@(PT_OFF_ORIG_D0),%d0 cmpl #NR_syscalls,%d0 jcs syscall + jra ret_from_syscall badsys: movel #-ENOSYS,%sp@(PT_OFF_D0) jra ret_from_syscall -- 2.17.1