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-rw-r--r--arch/Kconfig8
-rw-r--r--arch/s390/Kconfig1
-rw-r--r--arch/s390/include/asm/ptrace.h13
-rw-r--r--arch/s390/include/asm/syscall.h7
-rw-r--r--arch/s390/kernel/ftrace.c10
-rw-r--r--arch/s390/kernel/ptrace.c58
-rw-r--r--arch/sh/include/asm/syscall.h2
-rw-r--r--arch/sh/kernel/ftrace.c9
-rw-r--r--arch/sparc/include/asm/syscall.h7
-rw-r--r--arch/sparc/kernel/ftrace.c11
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/include/asm/syscall.h2
-rw-r--r--arch/x86/kernel/ftrace.c36
13 files changed, 124 insertions, 41 deletions
diff --git a/arch/Kconfig b/arch/Kconfig
index 06a13729c8d..215e46073c4 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -105,6 +105,14 @@ config HAVE_DMA_ATTRS
config USE_GENERIC_SMP_HELPERS
bool
+config HAVE_REGS_AND_STACK_ACCESS_API
+ bool
+ help
+ This symbol should be selected by an architecure if it supports
+ the API needed to access registers and stack entries from pt_regs,
+ declared in asm/ptrace.h
+ For example the kprobes-based event tracer needs this API.
+
config HAVE_CLK
bool
help
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 19deda8d887..0d8cd9bbe10 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -90,6 +90,7 @@ config S390
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_DEFAULT_NO_SPIN_MUTEXES
select HAVE_OPROFILE
select HAVE_KPROBES
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 95dcf183a28..dd2d913afca 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -492,13 +492,24 @@ struct user_regs_struct
struct task_struct;
extern void user_enable_single_step(struct task_struct *);
extern void user_disable_single_step(struct task_struct *);
+extern void show_regs(struct pt_regs * regs);
#define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0)
#define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN)
#define user_stack_pointer(regs)((regs)->gprs[15])
#define regs_return_value(regs)((regs)->gprs[2])
#define profile_pc(regs) instruction_pointer(regs)
-extern void show_regs(struct pt_regs * regs);
+
+int regs_query_register_offset(const char *name);
+const char *regs_query_register_name(unsigned int offset);
+unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset);
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n);
+
+static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
+{
+ return regs->gprs[15] & PSW_ADDR_INSN;
+}
+
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index e0a73d3eb83..8429686951f 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -15,6 +15,13 @@
#include <linux/sched.h>
#include <asm/ptrace.h>
+/*
+ * The syscall table always contains 32 bit pointers since we know that the
+ * address of the function to be called is (way) below 4GB. So the "int"
+ * type here is what we want [need] for both 32 bit and 64 bit systems.
+ */
+extern const unsigned int sys_call_table[];
+
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 314d8f09cf3..6a83d058131 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -200,13 +200,3 @@ out:
return parent;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned int sys_call_table[];
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-#endif
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 7cf46423441..33fdc5a7976 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -992,3 +992,61 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
#endif
return &user_s390_view;
}
+
+static const char *gpr_names[NUM_GPRS] = {
+ "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
+ "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
+};
+
+unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
+{
+ if (offset >= NUM_GPRS)
+ return 0;
+ return regs->gprs[offset];
+}
+
+int regs_query_register_offset(const char *name)
+{
+ unsigned long offset;
+
+ if (!name || *name != 'r')
+ return -EINVAL;
+ if (strict_strtoul(name + 1, 10, &offset))
+ return -EINVAL;
+ if (offset >= NUM_GPRS)
+ return -EINVAL;
+ return offset;
+}
+
+const char *regs_query_register_name(unsigned int offset)
+{
+ if (offset >= NUM_GPRS)
+ return NULL;
+ return gpr_names[offset];
+}
+
+static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ unsigned long ksp = kernel_stack_pointer(regs);
+
+ return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs:pt_regs which contains kernel stack pointer.
+ * @n:stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long addr;
+
+ addr = kernel_stack_pointer(regs) + n * sizeof(long);
+ if (!regs_within_kernel_stack(regs, addr))
+ return 0;
+ return *(unsigned long *)addr;
+}
diff --git a/arch/sh/include/asm/syscall.h b/arch/sh/include/asm/syscall.h
index 6a381429ee9..aa7777bdc37 100644
--- a/arch/sh/include/asm/syscall.h
+++ b/arch/sh/include/asm/syscall.h
@@ -1,6 +1,8 @@
#ifndef __ASM_SH_SYSCALL_H
#define __ASM_SH_SYSCALL_H
+extern const unsigned long sys_call_table[];
+
#ifdef CONFIG_SUPERH32
# include "syscall_32.h"
#else
diff --git a/arch/sh/kernel/ftrace.c b/arch/sh/kernel/ftrace.c
index a48cdedc73b..30e13196d35 100644
--- a/arch/sh/kernel/ftrace.c
+++ b/arch/sh/kernel/ftrace.c
@@ -399,12 +399,3 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
}
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-extern unsigned long *sys_call_table;
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-#endif /* CONFIG_FTRACE_SYSCALLS */
diff --git a/arch/sparc/include/asm/syscall.h b/arch/sparc/include/asm/syscall.h
index 7486c605e23..025a02ad2e3 100644
--- a/arch/sparc/include/asm/syscall.h
+++ b/arch/sparc/include/asm/syscall.h
@@ -5,6 +5,13 @@
#include <linux/sched.h>
#include <asm/ptrace.h>
+/*
+ * The syscall table always contains 32 bit pointers since we know that the
+ * address of the function to be called is (way) below 4GB. So the "int"
+ * type here is what we want [need] for both 32 bit and 64 bit systems.
+ */
+extern const unsigned int sys_call_table[];
+
/* The system call number is given by the user in %g1 */
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index 29973daa993..9103a56b39e 100644
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -91,14 +91,3 @@ int __init ftrace_dyn_arch_init(void *data)
return 0;
}
#endif
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned int sys_call_table[];
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)sys_call_table[nr];
-}
-
-#endif
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index eb4092568f9..0896008f750 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -45,6 +45,7 @@ config X86
select HAVE_GENERIC_DMA_COHERENT if X86_32
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select USER_STACKTRACE_SUPPORT
+ select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_DMA_API_DEBUG
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_BZIP2
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
index 8d33bc5462d..c4a348f7bd4 100644
--- a/arch/x86/include/asm/syscall.h
+++ b/arch/x86/include/asm/syscall.h
@@ -16,6 +16,8 @@
#include <linux/sched.h>
#include <linux/err.h>
+extern const unsigned long sys_call_table[];
+
/*
* Only the low 32 bits of orig_ax are meaningful, so we return int.
* This importantly ignores the high bits on 64-bit, so comparisons
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 30968924543..cd37469b54e 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -30,14 +30,32 @@
#ifdef CONFIG_DYNAMIC_FTRACE
+/*
+ * modifying_code is set to notify NMIs that they need to use
+ * memory barriers when entering or exiting. But we don't want
+ * to burden NMIs with unnecessary memory barriers when code
+ * modification is not being done (which is most of the time).
+ *
+ * A mutex is already held when ftrace_arch_code_modify_prepare
+ * and post_process are called. No locks need to be taken here.
+ *
+ * Stop machine will make sure currently running NMIs are done
+ * and new NMIs will see the updated variable before we need
+ * to worry about NMIs doing memory barriers.
+ */
+static int modifying_code __read_mostly;
+static DEFINE_PER_CPU(int, save_modifying_code);
+
int ftrace_arch_code_modify_prepare(void)
{
set_kernel_text_rw();
+ modifying_code = 1;
return 0;
}
int ftrace_arch_code_modify_post_process(void)
{
+ modifying_code = 0;
set_kernel_text_ro();
return 0;
}
@@ -149,6 +167,11 @@ static void ftrace_mod_code(void)
void ftrace_nmi_enter(void)
{
+ __get_cpu_var(save_modifying_code) = modifying_code;
+
+ if (!__get_cpu_var(save_modifying_code))
+ return;
+
if (atomic_inc_return(&nmi_running) & MOD_CODE_WRITE_FLAG) {
smp_rmb();
ftrace_mod_code();
@@ -160,6 +183,9 @@ void ftrace_nmi_enter(void)
void ftrace_nmi_exit(void)
{
+ if (!__get_cpu_var(save_modifying_code))
+ return;
+
/* Finish all executions before clearing nmi_running */
smp_mb();
atomic_dec(&nmi_running);
@@ -484,13 +510,3 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
}
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-#ifdef CONFIG_FTRACE_SYSCALLS
-
-extern unsigned long *sys_call_table;
-
-unsigned long __init arch_syscall_addr(int nr)
-{
- return (unsigned long)(&sys_call_table)[nr];
-}
-#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-26 15:19:31 +0000