Re: [PATCH v3 08/11] powerpc/tracing: fix compat syscall handling

[Marcin Nowakowski]

On 12.10.2016 11:59, Michael Ellerman wrote:

I went to test this and noticed the exit and enter events appear to be
reversed in time? (your series on top of 24532f768121)


thanks for testing the patch - I've found a bug that has sneaked in 
while cleaning up the patches before submission ... I'll fix it in the 
next iteration.


Marcin

Re: [PATCH v3 08/11] powerpc/tracing: fix compat syscall handling

[Michael Ellerman]

Marcin Nowakowski  writes:

> Adapt the code to make use of new syscall handling interface
>
> Signed-off-by: Marcin Nowakowski 
> Cc: Steven Rostedt 
> Cc: Ingo Molnar 
> Cc: Benjamin Herrenschmidt 
> Cc: Paul Mackerras 
> Cc: Michael Ellerman 
> Cc: linuxppc-dev@lists.ozlabs.org
> ---
>  arch/powerpc/include/asm/ftrace.h | 11 +++
>  arch/powerpc/kernel/ftrace.c  |  4 

I went to test this and noticed the exit and enter events appear to be
reversed in time? (your series on top of 24532f768121)

  ls-4221  [003] 83.766113: compat_sys_rt_sigprocmask -> 0x2
  ls-4221  [003] 83.766137: compat_sys_rt_sigprocmask(how: 2, nset: 
1010db30, oset: 0, sigsetsize: 8)
  ls-4221  [003] 83.766175: compat_sys_rt_sigaction -> 0x14
  ls-4221  [003] 83.766175: compat_sys_rt_sigaction(sig: 14, act: 
ffbd33c4, oact: ffbd3338, sigsetsize: 8)
  ls-4221  [003] 83.766177: compat_sys_rt_sigaction -> 0x15
  ls-4221  [003] 83.766177: compat_sys_rt_sigaction(sig: 15, act: 
ffbd33c4, oact: ffbd3338, sigsetsize: 8)
  ls-4221  [003] 83.766178: compat_sys_rt_sigaction -> 0x16
  ls-4221  [003] 83.766178: compat_sys_rt_sigaction(sig: 16, act: 
ffbd33d4, oact: ffbd3348, sigsetsize: 8)
  ls-4221  [003] 83.766179: sys_setpgid -> 0x107d
  ls-4221  [003] 83.766179: sys_setpgid(pid: 107d, pgid: 107d)
  ls-4221  [003] 83.766180: compat_sys_rt_sigprocmask -> 0x0
  ls-4221  [003] 83.766181: compat_sys_rt_sigprocmask(how: 0, nset: 
ffbd34b0, oset: ffbd3530, sigsetsize: 8)
  ls-4221  [003] 83.766186: compat_sys_ioctl -> 0xff
  ls-4221  [003] 83.766187: compat_sys_ioctl(fd: ff, cmd: 80047476, 
arg32: ffbd3488)
  ls-4221  [003] 83.766188: compat_sys_rt_sigprocmask -> 0x2
  ls-4221  [003] 83.766189: compat_sys_rt_sigprocmask(how: 2, nset: 
ffbd3530, oset: 0, sigsetsize: 8)
  ls-4221  [003] 83.766189: sys_close -> 0x4
  ls-4221  [003] 83.766190: sys_close(fd: 4)
  ls-4221  [003] 83.766191: sys_read -> 0x3
  ls-4221  [003] 83.766191: sys_read(fd: 3, buf: ffbd35dc, count: 1)
  ls-4221  [003] 83.766235: sys_close -> 0x3
  ls-4221  [003] 83.766235: sys_close(fd: 3)

cheers

[PATCH v3 08/11] powerpc/tracing: fix compat syscall handling

[Marcin Nowakowski]

Adapt the code to make use of new syscall handling interface

Signed-off-by: Marcin Nowakowski 
Cc: Steven Rostedt 
Cc: Ingo Molnar 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/include/asm/ftrace.h | 11 +++
 arch/powerpc/kernel/ftrace.c  |  4 
 2 files changed, 15 insertions(+)

diff --git a/arch/powerpc/include/asm/ftrace.h 
b/arch/powerpc/include/asm/ftrace.h
index 9697a73..d2ea3b6 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -86,6 +86,17 @@ static inline bool arch_syscall_match_sym_name(const char 
*sym, const char *name
return !strcmp(sym + prefix_len + 1, name + prefix_len);
 }
 #endif
+
+#if defined(CONFIG_COMPAT)
+#include 
+#include 
+
+#define ARCH_COMPAT_SYSCALL_NUMBERS_OVERLAP 1
+static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
+{
+   return in_compat_syscall();
+}
+#endif /* CONFIG_COMPAT */
 #endif /* CONFIG_FTRACE_SYSCALLS && !__ASSEMBLY__ */
 
 #endif /* _ASM_POWERPC_FTRACE */
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 5bfb35f..12c00f7 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -606,6 +606,10 @@ unsigned long prepare_ftrace_return(unsigned long parent, 
unsigned long ip)
 #if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_PPC64)
 unsigned long __init arch_syscall_addr(int nr, bool compat)
 {
+#ifdef CONFIG_COMPAT
+   if (compat)
+   return sys_call_table[nr*2+1];
+#endif
return sys_call_table[nr*2];
 }
 #endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_PPC64 */
-- 
2.7.4