diff options
| -rw-r--r-- | arch/x86/include/asm/ftrace.h | 24 | ||||
| -rw-r--r-- | arch/x86/include/asm/thread_info.h | 1 | ||||
| -rw-r--r-- | kernel/trace/trace_syscalls.c | 43 |
3 files changed, 62 insertions, 6 deletions
diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 86cb51e1ca96..0525a8bdf65d 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -72,4 +72,28 @@ int ftrace_int3_handler(struct pt_regs *regs); #endif /* __ASSEMBLY__ */ #endif /* CONFIG_FUNCTION_TRACER */ + +#if !defined(__ASSEMBLY__) && !defined(COMPILE_OFFSETS) + +#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION) +#include <asm/compat.h> + +/* + * Because ia32 syscalls do not map to x86_64 syscall numbers + * this screws up the trace output when tracing a ia32 task. + * Instead of reporting bogus syscalls, just do not trace them. + * + * If the user realy wants these, then they should use the + * raw syscall tracepoints with filtering. + */ +#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1 +static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) +{ + if (is_compat_task()) + return true; + return false; +} +#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */ +#endif /* !__ASSEMBLY__ && !COMPILE_OFFSETS */ + #endif /* _ASM_X86_FTRACE_H */ diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 2d946e63ee82..2cd056e3ada3 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -20,7 +20,6 @@ struct task_struct; struct exec_domain; #include <asm/processor.h> -#include <asm/ftrace.h> #include <linux/atomic.h> struct thread_info { diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 5329e13e74a1..7a809e321058 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -1,5 +1,6 @@ #include <trace/syscall.h> #include <trace/events/syscalls.h> +#include <linux/syscalls.h> #include <linux/slab.h> #include <linux/kernel.h> #include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */ @@ -47,6 +48,38 @@ static inline bool arch_syscall_match_sym_name(const char *sym, const char *name } #endif +#ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS +/* + * Some architectures that allow for 32bit applications + * to run on a 64bit kernel, do not map the syscalls for + * the 32bit tasks the same as they do for 64bit tasks. + * + * *cough*x86*cough* + * + * In such a case, instead of reporting the wrong syscalls, + * simply ignore them. + * + * For an arch to ignore the compat syscalls it needs to + * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as + * define the function arch_trace_is_compat_syscall() to let + * the tracing system know that it should ignore it. + */ +static int +trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) +{ + if (unlikely(arch_trace_is_compat_syscall(regs))) + return -1; + + return syscall_get_nr(task, regs); +} +#else +static inline int +trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) +{ + return syscall_get_nr(task, regs); +} +#endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */ + static __init struct syscall_metadata * find_syscall_meta(unsigned long syscall) { @@ -276,10 +309,10 @@ static void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id) struct syscall_metadata *sys_data; struct ring_buffer_event *event; struct ring_buffer *buffer; - int size; int syscall_nr; + int size; - syscall_nr = syscall_get_nr(current, regs); + syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; if (!test_bit(syscall_nr, enabled_enter_syscalls)) @@ -313,7 +346,7 @@ static void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret) struct ring_buffer *buffer; int syscall_nr; - syscall_nr = syscall_get_nr(current, regs); + syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; if (!test_bit(syscall_nr, enabled_exit_syscalls)) @@ -502,7 +535,7 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) int rctx; int size; - syscall_nr = syscall_get_nr(current, regs); + syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) @@ -578,7 +611,7 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) int rctx; int size; - syscall_nr = syscall_get_nr(current, regs); + syscall_nr = trace_get_syscall_nr(current, regs); if (syscall_nr < 0) return; if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) |