From d4d67150165df8bf1cc05e532f6efca96f907cab Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 9 Jul 2008 02:38:07 -0700 Subject: x86 ptrace: unify syscall tracing This unifies and cleans up the syscall tracing code on i386 and x86_64. Using a single function for entry and exit tracing on 32-bit made the do_syscall_trace() into some terrible spaghetti. The logic is clear and simple using separate syscall_trace_enter() and syscall_trace_leave() functions as on 64-bit. The unification adds PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP support on x86_64, for 32-bit ptrace() callers and for 64-bit ptrace() callers tracing either 32-bit or 64-bit tasks. It behaves just like 32-bit. Changing syscall_trace_enter() to return the syscall number shortens all the assembly paths, while adding the SYSEMU feature in a simple way. Signed-off-by: Roland McGrath --- arch/x86/ia32/ia32entry.S | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'arch/x86/ia32') diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 20371d0635e..8796d190525 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -37,6 +37,11 @@ movq %rax,R8(%rsp) .endm + /* + * Reload arg registers from stack in case ptrace changed them. + * We don't reload %eax because syscall_trace_enter() returned + * the value it wants us to use in the table lookup. + */ .macro LOAD_ARGS32 offset movl \offset(%rsp),%r11d movl \offset+8(%rsp),%r10d @@ -46,7 +51,6 @@ movl \offset+48(%rsp),%edx movl \offset+56(%rsp),%esi movl \offset+64(%rsp),%edi - movl \offset+72(%rsp),%eax .endm .macro CFI_STARTPROC32 simple @@ -137,13 +141,12 @@ ENTRY(ia32_sysenter_target) .previous GET_THREAD_INFO(%r10) orl $TS_COMPAT,TI_status(%r10) - testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP), \ - TI_flags(%r10) + testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10) CFI_REMEMBER_STATE jnz sysenter_tracesys -sysenter_do_call: cmpl $(IA32_NR_syscalls-1),%eax ja ia32_badsys +sysenter_do_call: IA32_ARG_FIXUP 1 call *ia32_sys_call_table(,%rax,8) movq %rax,RAX-ARGOFFSET(%rsp) @@ -242,8 +245,7 @@ ENTRY(ia32_cstar_target) .previous GET_THREAD_INFO(%r10) orl $TS_COMPAT,TI_status(%r10) - testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP), \ - TI_flags(%r10) + testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10) CFI_REMEMBER_STATE jnz cstar_tracesys cstar_do_call: @@ -336,8 +338,7 @@ ENTRY(ia32_syscall) SAVE_ARGS 0,0,1 GET_THREAD_INFO(%r10) orl $TS_COMPAT,TI_status(%r10) - testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP), \ - TI_flags(%r10) + testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10) jnz ia32_tracesys ia32_do_syscall: cmpl $(IA32_NR_syscalls-1),%eax -- cgit v1.2.3