* How to trace compat syscalls? [Was Re: [PATCH] MIPS: use 32-bit wrapper for compat_sys_futex] [not found] ` <20110818201911.GF22920@linux-mips.org> @ 2011-08-19 3:49 ` Yong Zhang 2011-08-19 4:15 ` Yong Zhang 0 siblings, 1 reply; 2+ messages in thread From: Yong Zhang @ 2011-08-19 3:49 UTC (permalink / raw) To: Ralf Baechle Cc: David Daney, linux-mips, linux-kernel, linux-arch, Yong Zhang, Steven Rostedt, Frederic Weisbecker, Ingo Molnar, Martin Schwidefsky, David S. Miller, Thomas Gleixner, Andrew Morton Cc'ing more people. On Thu, Aug 18, 2011 at 09:19:11PM +0100, Ralf Baechle wrote: > > But really I think this patch fixes things at the wrong level. Each > > architecture potentially needs a similar patch. What would happen if > > we did something like: > > > +++ b/kernel/futex_compat.c > > @@ -180,9 +180,9 @@ err_unlock: > > return ret; > > } > > > > -asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, > > - struct compat_timespec __user *utime, u32 __user *uaddr2, > > - u32 val3) > > +SYSCALL_DEFINE6(compat_sys_futex, u32 __user *, uaddr, int , op, u32, val, > > + struct compat_timespec __user *, utime, u32 __user *, uaddr2, > > + u32, val3) > > { > > struct timespec ts; > > ktime_t t, *tp = NULL; > > > > Obviously the function name is wrong, but a varient of > > SYSCALL_DEFINE*() could be created so the proper function names are > > produced. > > Right now none of the the generic compat_ functions is wrapped in > SYSCALL_DEFINE* because for some architectures a further wrapper function > is needed. It seems some architectures call compat_ calls directly > without SYSCALL_DEFINE* which with CONFIG_FTRACE_SYSCALLS is a bug ... Just checked some archs which have HAVE_SYSCALL_TRACEPOINTS=y and could call compat_* syscalls when run 32bit process on 64bit kernel, I don't find any special code against FTRACE_SYSCALLS. So that means we could not trace compat syscalls even if we want to(Am I missing something?). So I think if we want to trace it, the easy way is just like what we have done on normal syscalls, IOW, we could SYSCALL_DEFINE all of the compat syscalls. Thought? BTW, I have make a trival patch to introduce COMPAT_SYSCALL_DEFINE, it's just for calling of inspiration(no test no build, and I leave SYSCALL_METADATA etc untouched.) Thanks, Yong --- diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 8c03b98..e79027f 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -221,26 +221,38 @@ extern struct trace_event_functions exit_syscall_print_funcs; __SC_STR_ADECL##x(__VA_ARGS__) \ }; \ SYSCALL_METADATA(sname, x); \ - __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) + __SYSCALL_DEFINEx(, x, sname, __VA_ARGS__) + +#define COMPAT_SYSCALL_DEFINEx(x, sname, ...) \ + static const char *types_compat_##sname[] = { \ + __SC_STR_TDECL##x(__VA_ARGS__) \ + }; \ + static const char *args_compat_##sname[] = { \ + __SC_STR_ADECL##x(__VA_ARGS__) \ + }; \ + SYSCALL_METADATA(compat, sname, x); \ + __SYSCALL_DEFINEx(cmopat_, x, sname, __VA_ARGS__) #else #define SYSCALL_DEFINEx(x, sname, ...) \ - __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) + __SYSCALL_DEFINEx(, x, sname, __VA_ARGS__) +#define COMPAT_SYSCALL_DEFINEx(x, sname, ...) \ + __SYSCALL_DEFINEx(compat_, x, sname, __VA_ARGS__) #endif #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -#define SYSCALL_DEFINE(name) static inline long SYSC_##name +#define SYSCALL_DEFINE(compat, name) static inline long compat##SYSC_##name -#define __SYSCALL_DEFINEx(x, name, ...) \ - asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__)); \ - static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__)); \ - asmlinkage long SyS##name(__SC_LONG##x(__VA_ARGS__)) \ +#define __SYSCALL_DEFINEx(compat, x, name, ...) \ + asmlinkage long compat##sys##name(__SC_DECL##x(__VA_ARGS__)); \ + static inline long compat##SYSC##name(__SC_DECL##x(__VA_ARGS__));\ + asmlinkage long compat##SyS##name(__SC_LONG##x(__VA_ARGS__)) \ { \ __SC_TEST##x(__VA_ARGS__); \ - return (long) SYSC##name(__SC_CAST##x(__VA_ARGS__)); \ + return (long) compat##SYSC##name(__SC_CAST##x(__VA_ARGS__));\ } \ - SYSCALL_ALIAS(sys##name, SyS##name); \ - static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__)) + SYSCALL_ALIAS(compat##sys##name, compat##SyS##name); \ + static inline long compat##SYSC##name(__SC_DECL##x(__VA_ARGS__)) #else /* CONFIG_HAVE_SYSCALL_WRAPPERS */ ^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: How to trace compat syscalls? [Was Re: [PATCH] MIPS: use 32-bit wrapper for compat_sys_futex] 2011-08-19 3:49 ` How to trace compat syscalls? [Was Re: [PATCH] MIPS: use 32-bit wrapper for compat_sys_futex] Yong Zhang @ 2011-08-19 4:15 ` Yong Zhang 0 siblings, 0 replies; 2+ messages in thread From: Yong Zhang @ 2011-08-19 4:15 UTC (permalink / raw) To: Ralf Baechle Cc: David Daney, linux-mips, linux-kernel, linux-arch, Yong Zhang, Steven Rostedt, Frederic Weisbecker, Ingo Molnar, Martin Schwidefsky, David S. Miller, Thomas Gleixner, Andrew Morton On Fri, Aug 19, 2011 at 11:49:50AM +0800, Yong Zhang wrote: > Cc'ing more people. > > On Thu, Aug 18, 2011 at 09:19:11PM +0100, Ralf Baechle wrote: > > > But really I think this patch fixes things at the wrong level. Each > > > architecture potentially needs a similar patch. What would happen if > > > we did something like: > > > > > +++ b/kernel/futex_compat.c > > > @@ -180,9 +180,9 @@ err_unlock: > > > return ret; > > > } > > > > > > -asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, > > > - struct compat_timespec __user *utime, u32 __user *uaddr2, > > > - u32 val3) > > > +SYSCALL_DEFINE6(compat_sys_futex, u32 __user *, uaddr, int , op, u32, val, > > > + struct compat_timespec __user *, utime, u32 __user *, uaddr2, > > > + u32, val3) > > > { > > > struct timespec ts; > > > ktime_t t, *tp = NULL; > > > > > > Obviously the function name is wrong, but a varient of > > > SYSCALL_DEFINE*() could be created so the proper function names are > > > produced. > > > > Right now none of the the generic compat_ functions is wrapped in > > SYSCALL_DEFINE* because for some architectures a further wrapper function > > is needed. It seems some architectures call compat_ calls directly > > without SYSCALL_DEFINE* which with CONFIG_FTRACE_SYSCALLS is a bug ... > > Just checked some archs which have HAVE_SYSCALL_TRACEPOINTS=y and could > call compat_* syscalls when run 32bit process on 64bit kernel, I don't > find any special code against FTRACE_SYSCALLS. So that means we could > not trace compat syscalls even if we want to(Am I missing something?). > So I think if we want to trace it, the easy way is just like what we have > done on normal syscalls, IOW, we could SYSCALL_DEFINE all of the compat > syscalls. Except the ones which call sys_* finally, :) > > Thought? > > BTW, I have make a trival patch to introduce COMPAT_SYSCALL_DEFINE, it's just > for calling of inspiration(no test no build, and I leave SYSCALL_METADATA > etc untouched.) > > Thanks, > Yong > > --- > diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h > index 8c03b98..e79027f 100644 > --- a/include/linux/syscalls.h > +++ b/include/linux/syscalls.h > @@ -221,26 +221,38 @@ extern struct trace_event_functions exit_syscall_print_funcs; > __SC_STR_ADECL##x(__VA_ARGS__) \ > }; \ > SYSCALL_METADATA(sname, x); \ > - __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) > + __SYSCALL_DEFINEx(, x, sname, __VA_ARGS__) > + > +#define COMPAT_SYSCALL_DEFINEx(x, sname, ...) \ > + static const char *types_compat_##sname[] = { \ > + __SC_STR_TDECL##x(__VA_ARGS__) \ > + }; \ > + static const char *args_compat_##sname[] = { \ > + __SC_STR_ADECL##x(__VA_ARGS__) \ > + }; \ > + SYSCALL_METADATA(compat, sname, x); \ > + __SYSCALL_DEFINEx(cmopat_, x, sname, __VA_ARGS__) > #else > #define SYSCALL_DEFINEx(x, sname, ...) \ > - __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) > + __SYSCALL_DEFINEx(, x, sname, __VA_ARGS__) > +#define COMPAT_SYSCALL_DEFINEx(x, sname, ...) \ > + __SYSCALL_DEFINEx(compat_, x, sname, __VA_ARGS__) > #endif > > #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS > > -#define SYSCALL_DEFINE(name) static inline long SYSC_##name > +#define SYSCALL_DEFINE(compat, name) static inline long compat##SYSC_##name > > -#define __SYSCALL_DEFINEx(x, name, ...) \ > - asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__)); \ > - static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__)); \ > - asmlinkage long SyS##name(__SC_LONG##x(__VA_ARGS__)) \ > +#define __SYSCALL_DEFINEx(compat, x, name, ...) \ > + asmlinkage long compat##sys##name(__SC_DECL##x(__VA_ARGS__)); \ > + static inline long compat##SYSC##name(__SC_DECL##x(__VA_ARGS__));\ > + asmlinkage long compat##SyS##name(__SC_LONG##x(__VA_ARGS__)) \ > { \ > __SC_TEST##x(__VA_ARGS__); \ > - return (long) SYSC##name(__SC_CAST##x(__VA_ARGS__)); \ > + return (long) compat##SYSC##name(__SC_CAST##x(__VA_ARGS__));\ > } \ > - SYSCALL_ALIAS(sys##name, SyS##name); \ > - static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__)) > + SYSCALL_ALIAS(compat##sys##name, compat##SyS##name); \ > + static inline long compat##SYSC##name(__SC_DECL##x(__VA_ARGS__)) > > #else /* CONFIG_HAVE_SYSCALL_WRAPPERS */ > ^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2011-08-19 4:16 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <1313546094-11882-1-git-send-email-yong.zhang@windriver.com>
[not found] ` <4E4BF7C0.80703@cavium.com>
[not found] ` <20110818201911.GF22920@linux-mips.org>
2011-08-19 3:49 ` How to trace compat syscalls? [Was Re: [PATCH] MIPS: use 32-bit wrapper for compat_sys_futex] Yong Zhang
2011-08-19 4:15 ` Yong Zhang
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox