mirror of
https://github.com/torvalds/linux.git
synced 2024-12-26 04:42:12 +00:00
a846446b19
The result of in_compat_syscall() can be pictured as:
x86 platform:
---------------------------------------------------
| Arch\syscall | 64-bit | ia32 | x32 |
|-------------------------------------------------|
| x86_64 | false | true | true |
|-------------------------------------------------|
| i686 | | <true> | |
---------------------------------------------------
Other platforms:
-------------------------------------------
| Arch\syscall | 64-bit | compat |
|-----------------------------------------|
| 64-bit | false | true |
|-----------------------------------------|
| 32-bit(?) | | <false> |
-------------------------------------------
As seen, the result of in_compat_syscall() on generic 32-bit platform
differs from i686.
There is no reason for in_compat_syscall() == true on native i686. It also
easy to misread code if the result on native 32-bit platform differs
between arches.
Because of that non arch-specific code has many places with:
if (IS_ENABLED(CONFIG_COMPAT) && in_compat_syscall())
in different variations.
It looks-like the only non-x86 code which uses in_compat_syscall() not
under CONFIG_COMPAT guard is in amd/amdkfd. But according to the commit
a18069c132 ("amdkfd: Disable support for 32-bit user processes"), it
actually should be disabled on native i686.
Rename in_compat_syscall() to in_32bit_syscall() for x86-specific code
and make in_compat_syscall() false under !CONFIG_COMPAT.
A follow on patch will clean up generic users which were forced to check
IS_ENABLED(CONFIG_COMPAT) with in_compat_syscall().
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-efi@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: https://lkml.kernel.org/r/20181012134253.23266-2-dima@arista.com
86 lines
2.2 KiB
C
86 lines
2.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_FTRACE_H
|
|
#define _ASM_X86_FTRACE_H
|
|
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
#ifdef CC_USING_FENTRY
|
|
# define MCOUNT_ADDR ((unsigned long)(__fentry__))
|
|
#else
|
|
# define MCOUNT_ADDR ((unsigned long)(mcount))
|
|
# define HAVE_FUNCTION_GRAPH_FP_TEST
|
|
#endif
|
|
#define MCOUNT_INSN_SIZE 5 /* sizeof mcount call */
|
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE
|
|
#define ARCH_SUPPORTS_FTRACE_OPS 1
|
|
#endif
|
|
|
|
#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
|
|
|
|
#ifndef __ASSEMBLY__
|
|
extern void mcount(void);
|
|
extern atomic_t modifying_ftrace_code;
|
|
extern void __fentry__(void);
|
|
|
|
static inline unsigned long ftrace_call_adjust(unsigned long addr)
|
|
{
|
|
/*
|
|
* addr is the address of the mcount call instruction.
|
|
* recordmcount does the necessary offset calculation.
|
|
*/
|
|
return addr;
|
|
}
|
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE
|
|
|
|
struct dyn_arch_ftrace {
|
|
/* No extra data needed for x86 */
|
|
};
|
|
|
|
int ftrace_int3_handler(struct pt_regs *regs);
|
|
|
|
#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
|
|
|
|
#endif /* CONFIG_DYNAMIC_FTRACE */
|
|
#endif /* __ASSEMBLY__ */
|
|
#endif /* CONFIG_FUNCTION_TRACER */
|
|
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
|
|
static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
|
|
{
|
|
/*
|
|
* Compare the symbol name with the system call name. Skip the
|
|
* "__x64_sys", "__ia32_sys" or simple "sys" prefix.
|
|
*/
|
|
return !strcmp(sym + 3, name + 3) ||
|
|
(!strncmp(sym, "__x64_", 6) && !strcmp(sym + 9, name + 3)) ||
|
|
(!strncmp(sym, "__ia32_", 7) && !strcmp(sym + 10, name + 3));
|
|
}
|
|
|
|
#ifndef COMPILE_OFFSETS
|
|
|
|
#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION)
|
|
#include <linux/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 really 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)
|
|
{
|
|
return in_32bit_syscall();
|
|
}
|
|
#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */
|
|
#endif /* !COMPILE_OFFSETS */
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
#endif /* _ASM_X86_FTRACE_H */
|