mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-11 11:09:13 +00:00
f44d5c4890
- Fix a crash when having function tracing and function stack tracing on
the command line. The ftrace trampolines are created as executable and
read only. But the stack tracer tries to modify them with text_poke()
which expects all kernel text to still be writable at boot.
Keep the trampolines writable at boot, and convert them to read-only
with the rest of the kernel.
- A selftest was triggering in the ring buffer iterator code, that
is no longer valid with the update of keeping the ring buffer
writable while a iterator is reading. Just bail after three failed
attempts to get an event and remove the warning and disabling of the
ring buffer.
- While modifying the ring buffer code, decided to remove all the
unnecessary BUG() calls.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXr1CDhQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qsXcAQCoL229SBrtHsn4DUO7eAQRppUT3hNw
RuKzvQ56+1GccQEAh8VGCeg89uMSK6imrTujEl6VmOUdbgrD5R96yiKoGQw=
=vi+k
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing fixes from Steven Rostedt:
"Various tracing fixes:
- Fix a crash when having function tracing and function stack tracing
on the command line.
The ftrace trampolines are created as executable and read only. But
the stack tracer tries to modify them with text_poke() which
expects all kernel text to still be writable at boot. Keep the
trampolines writable at boot, and convert them to read-only with
the rest of the kernel.
- A selftest was triggering in the ring buffer iterator code, that is
no longer valid with the update of keeping the ring buffer writable
while a iterator is reading.
Just bail after three failed attempts to get an event and remove
the warning and disabling of the ring buffer.
- While modifying the ring buffer code, decided to remove all the
unnecessary BUG() calls"
* tag 'trace-v5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Remove all BUG() calls
ring-buffer: Don't deactivate the ring buffer on failed iterator reads
x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot up
100 lines
2.8 KiB
C
100 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_FTRACE_H
|
|
#define _ASM_X86_FTRACE_H
|
|
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
#ifndef CC_USING_FENTRY
|
|
# error Compiler does not support fentry?
|
|
#endif
|
|
# define MCOUNT_ADDR ((unsigned long)(__fentry__))
|
|
#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 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;
|
|
}
|
|
|
|
/*
|
|
* When a ftrace registered caller is tracing a function that is
|
|
* also set by a register_ftrace_direct() call, it needs to be
|
|
* differentiated in the ftrace_caller trampoline. To do this, we
|
|
* place the direct caller in the ORIG_AX part of pt_regs. This
|
|
* tells the ftrace_caller that there's a direct caller.
|
|
*/
|
|
static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr)
|
|
{
|
|
/* Emulate a call */
|
|
regs->orig_ax = addr;
|
|
}
|
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE
|
|
|
|
struct dyn_arch_ftrace {
|
|
/* No extra data needed for x86 */
|
|
};
|
|
|
|
#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
|
|
|
|
#endif /* CONFIG_DYNAMIC_FTRACE */
|
|
#endif /* __ASSEMBLY__ */
|
|
#endif /* CONFIG_FUNCTION_TRACER */
|
|
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
|
|
extern void set_ftrace_ops_ro(void);
|
|
#else
|
|
static inline void set_ftrace_ops_ro(void) { }
|
|
#endif
|
|
|
|
#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", "__do_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)) ||
|
|
(!strncmp(sym, "__do_sys", 8) && !strcmp(sym + 8, 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 */
|