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-rw-r--r--arch/sh/Kconfig1
-rw-r--r--arch/sh/Kconfig.debug11
-rw-r--r--arch/sh/include/asm/ftrace.h3
-rw-r--r--arch/sh/include/asm/thread_info.h2
-rw-r--r--arch/sh/kernel/Makefile_321
-rw-r--r--arch/sh/kernel/asm-offsets.c1
-rw-r--r--arch/sh/kernel/ftrace.c122
-rw-r--r--arch/sh/kernel/process_32.c5
-rw-r--r--arch/sh/kernel/vmlinux_64.lds.S0
-rw-r--r--arch/sh/lib/Makefile1
-rw-r--r--arch/sh/lib/mcount.S202
11 files changed, 345 insertions, 4 deletions
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 46d1a5e71f7..120bd31a46e 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -34,6 +34,7 @@ config SUPERH32
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_SYSCALLS
+ select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_ARCH_KGDB
select ARCH_HIBERNATION_POSSIBLE if MMU
diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index 39224b57c6e..52a132c24aa 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -123,4 +123,15 @@ config SH64_SR_WATCH
bool "Debug: set SR.WATCH to enable hardware watchpoints and trace"
depends on SUPERH64
+config STACK_DEBUG
+ bool "Enable diagnostic checks of the kernel stack"
+ depends on FUNCTION_TRACER
+ select DEBUG_STACKOVERFLOW
+ default n
+ help
+ This option allows checks to be performed on the kernel stack
+ at runtime. Saying Y here will add overhead to every function
+ call and will therefore incur a major performance hit. Most
+ users should say N.
+
endmenu
diff --git a/arch/sh/include/asm/ftrace.h b/arch/sh/include/asm/ftrace.h
index b09311ad1db..7e0bcc4d4a9 100644
--- a/arch/sh/include/asm/ftrace.h
+++ b/arch/sh/include/asm/ftrace.h
@@ -13,8 +13,11 @@ extern void mcount(void);
#ifdef CONFIG_DYNAMIC_FTRACE
#define CALL_ADDR ((long)(ftrace_call))
#define STUB_ADDR ((long)(ftrace_stub))
+#define GRAPH_ADDR ((long)(ftrace_graph_call))
+#define CALLER_ADDR ((long)(ftrace_caller))
#define MCOUNT_INSN_OFFSET ((STUB_ADDR - CALL_ADDR) - 4)
+#define GRAPH_INSN_OFFSET ((CALLER_ADDR - GRAPH_ADDR) - 4)
struct dyn_arch_ftrace {
/* No extra data needed on sh */
diff --git a/arch/sh/include/asm/thread_info.h b/arch/sh/include/asm/thread_info.h
index 499e315f4be..5123bcaa850 100644
--- a/arch/sh/include/asm/thread_info.h
+++ b/arch/sh/include/asm/thread_info.h
@@ -51,7 +51,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
diff --git a/arch/sh/kernel/Makefile_32 b/arch/sh/kernel/Makefile_32
index fee924a9c46..94ed99b6800 100644
--- a/arch/sh/kernel/Makefile_32
+++ b/arch/sh/kernel/Makefile_32
@@ -30,6 +30,7 @@ obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_GENERIC_GPIO) += gpio.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
+obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_DUMP_CODE) += disassemble.o
obj-$(CONFIG_HIBERNATION) += swsusp.o
diff --git a/arch/sh/kernel/asm-offsets.c b/arch/sh/kernel/asm-offsets.c
index 99aceb28ee2..d218e808294 100644
--- a/arch/sh/kernel/asm-offsets.c
+++ b/arch/sh/kernel/asm-offsets.c
@@ -26,6 +26,7 @@ int main(void)
DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
DEFINE(TI_PRE_COUNT, offsetof(struct thread_info, preempt_count));
DEFINE(TI_RESTART_BLOCK,offsetof(struct thread_info, restart_block));
+ DEFINE(TI_SIZE, sizeof(struct thread_info));
#ifdef CONFIG_HIBERNATION
DEFINE(PBE_ADDRESS, offsetof(struct pbe, address));
diff --git a/arch/sh/kernel/ftrace.c b/arch/sh/kernel/ftrace.c
index 4f62eced0ae..6647dfcb781 100644
--- a/arch/sh/kernel/ftrace.c
+++ b/arch/sh/kernel/ftrace.c
@@ -16,11 +16,13 @@
#include <linux/string.h>
#include <linux/init.h>
#include <linux/io.h>
+#include <linux/kernel.h>
#include <asm/ftrace.h>
#include <asm/cacheflush.h>
#include <asm/unistd.h>
#include <trace/syscall.h>
+#ifdef CONFIG_DYNAMIC_FTRACE
static unsigned char ftrace_replaced_code[MCOUNT_INSN_SIZE];
static unsigned char ftrace_nop[4];
@@ -133,6 +135,126 @@ int __init ftrace_dyn_arch_init(void *data)
return 0;
}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+#ifdef CONFIG_DYNAMIC_FTRACE
+extern void ftrace_graph_call(void);
+
+static int ftrace_mod(unsigned long ip, unsigned long old_addr,
+ unsigned long new_addr)
+{
+ unsigned char code[MCOUNT_INSN_SIZE];
+
+ if (probe_kernel_read(code, (void *)ip, MCOUNT_INSN_SIZE))
+ return -EFAULT;
+
+ if (old_addr != __raw_readl((unsigned long *)code))
+ return -EINVAL;
+
+ __raw_writel(new_addr, ip);
+ return 0;
+}
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+ unsigned long ip, old_addr, new_addr;
+
+ ip = (unsigned long)(&ftrace_graph_call) + GRAPH_INSN_OFFSET;
+ old_addr = (unsigned long)(&skip_trace);
+ new_addr = (unsigned long)(&ftrace_graph_caller);
+
+ return ftrace_mod(ip, old_addr, new_addr);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+ unsigned long ip, old_addr, new_addr;
+
+ ip = (unsigned long)(&ftrace_graph_call) + GRAPH_INSN_OFFSET;
+ old_addr = (unsigned long)(&ftrace_graph_caller);
+ new_addr = (unsigned long)(&skip_trace);
+
+ return ftrace_mod(ip, old_addr, new_addr);
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+/*
+ * Hook the return address and push it in the stack of return addrs
+ * in the current thread info.
+ *
+ * This is the main routine for the function graph tracer. The function
+ * graph tracer essentially works like this:
+ *
+ * parent is the stack address containing self_addr's return address.
+ * We pull the real return address out of parent and store it in
+ * current's ret_stack. Then, we replace the return address on the stack
+ * with the address of return_to_handler. self_addr is the function that
+ * called mcount.
+ *
+ * When self_addr returns, it will jump to return_to_handler which calls
+ * ftrace_return_to_handler. ftrace_return_to_handler will pull the real
+ * return address off of current's ret_stack and jump to it.
+ */
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
+{
+ unsigned long old;
+ int faulted, err;
+ struct ftrace_graph_ent trace;
+ unsigned long return_hooker = (unsigned long)&return_to_handler;
+
+ if (unlikely(atomic_read(&current->tracing_graph_pause)))
+ return;
+
+ /*
+ * Protect against fault, even if it shouldn't
+ * happen. This tool is too much intrusive to
+ * ignore such a protection.
+ */
+ __asm__ __volatile__(
+ "1: \n\t"
+ "mov.l @%2, %0 \n\t"
+ "2: \n\t"
+ "mov.l %3, @%2 \n\t"
+ "mov #0, %1 \n\t"
+ "3: \n\t"
+ ".section .fixup, \"ax\" \n\t"
+ "4: \n\t"
+ "mov.l 5f, %0 \n\t"
+ "jmp @%0 \n\t"
+ " mov #1, %1 \n\t"
+ ".balign 4 \n\t"
+ "5: .long 3b \n\t"
+ ".previous \n\t"
+ ".section __ex_table,\"a\" \n\t"
+ ".long 1b, 4b \n\t"
+ ".long 2b, 4b \n\t"
+ ".previous \n\t"
+ : "=&r" (old), "=r" (faulted)
+ : "r" (parent), "r" (return_hooker)
+ );
+
+ if (unlikely(faulted)) {
+ ftrace_graph_stop();
+ WARN_ON(1);
+ return;
+ }
+
+ err = ftrace_push_return_trace(old, self_addr, &trace.depth, 0);
+ if (err == -EBUSY) {
+ __raw_writel(old, parent);
+ return;
+ }
+
+ trace.func = self_addr;
+
+ /* Only trace if the calling function expects to */
+ if (!ftrace_graph_entry(&trace)) {
+ current->curr_ret_stack--;
+ __raw_writel(old, parent);
+ }
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
#ifdef CONFIG_FTRACE_SYSCALLS
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
index 92d7740faab..9fee977f176 100644
--- a/arch/sh/kernel/process_32.c
+++ b/arch/sh/kernel/process_32.c
@@ -23,6 +23,7 @@
#include <linux/tick.h>
#include <linux/reboot.h>
#include <linux/fs.h>
+#include <linux/ftrace.h>
#include <linux/preempt.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
@@ -264,8 +265,8 @@ static void ubc_set_tracing(int asid, unsigned long pc)
* switch_to(x,y) should switch tasks from x to y.
*
*/
-struct task_struct *__switch_to(struct task_struct *prev,
- struct task_struct *next)
+__notrace_funcgraph struct task_struct *
+__switch_to(struct task_struct *prev, struct task_struct *next)
{
#if defined(CONFIG_SH_FPU)
unlazy_fpu(prev, task_pt_regs(prev));
diff --git a/arch/sh/kernel/vmlinux_64.lds.S b/arch/sh/kernel/vmlinux_64.lds.S
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/arch/sh/kernel/vmlinux_64.lds.S
diff --git a/arch/sh/lib/Makefile b/arch/sh/lib/Makefile
index aaea580b65b..19328d90a2d 100644
--- a/arch/sh/lib/Makefile
+++ b/arch/sh/lib/Makefile
@@ -25,6 +25,7 @@ memcpy-$(CONFIG_CPU_SH4) := memcpy-sh4.o
lib-$(CONFIG_MMU) += copy_page.o clear_page.o
lib-$(CONFIG_FUNCTION_TRACER) += mcount.o
+lib-$(CONFIG_FUNCTION_GRAPH_TRACER) += mcount.o
lib-y += $(memcpy-y) $(udivsi3-y)
EXTRA_CFLAGS += -Werror
diff --git a/arch/sh/lib/mcount.S b/arch/sh/lib/mcount.S
index 71e87f9b4fd..bd3ec648bec 100644
--- a/arch/sh/lib/mcount.S
+++ b/arch/sh/lib/mcount.S
@@ -9,6 +9,8 @@
* for more details.
*/
#include <asm/ftrace.h>
+#include <asm/thread_info.h>
+#include <asm/asm-offsets.h>
#define MCOUNT_ENTER() \
mov.l r4, @-r15; \
@@ -28,6 +30,55 @@
rts; \
mov.l @r15+, r4
+#ifdef CONFIG_STACK_DEBUG
+/*
+ * Perform diagnostic checks on the state of the kernel stack.
+ *
+ * Check for stack overflow. If there is less than 1KB free
+ * then it has overflowed.
+ *
+ * Make sure the stack pointer contains a valid address. Valid
+ * addresses for kernel stacks are anywhere after the bss
+ * (after _ebss) and anywhere in init_thread_union (init_stack).
+ */
+#define STACK_CHECK() \
+ mov #(THREAD_SIZE >> 10), r0; \
+ shll8 r0; \
+ shll2 r0; \
+ \
+ /* r1 = sp & (THREAD_SIZE - 1) */ \
+ mov #-1, r1; \
+ add r0, r1; \
+ and r15, r1; \
+ \
+ mov #TI_SIZE, r3; \
+ mov #(STACK_WARN >> 8), r2; \
+ shll8 r2; \
+ add r3, r2; \
+ \
+ /* Is the stack overflowing? */ \
+ cmp/hi r2, r1; \
+ bf stack_panic; \
+ \
+ /* If sp > _ebss then we're OK. */ \
+ mov.l .L_ebss, r1; \
+ cmp/hi r1, r15; \
+ bt 1f; \
+ \
+ /* If sp < init_stack, we're not OK. */ \
+ mov.l .L_init_thread_union, r1; \
+ cmp/hs r1, r15; \
+ bf stack_panic; \
+ \
+ /* If sp > init_stack && sp < _ebss, not OK. */ \
+ add r0, r1; \
+ cmp/hs r1, r15; \
+ bt stack_panic; \
+1:
+#else
+#define STACK_CHECK()
+#endif /* CONFIG_STACK_DEBUG */
+
.align 2
.globl _mcount
.type _mcount,@function
@@ -41,6 +92,8 @@ mcount:
tst r0, r0
bf ftrace_stub
#endif
+ STACK_CHECK()
+
MCOUNT_ENTER()
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -58,14 +111,62 @@ mcount_call:
jsr @r6
nop
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ mov.l .Lftrace_graph_return, r6
+ mov.l .Lftrace_stub, r7
+ cmp/eq r6, r7
+ bt 1f
+
+ mov.l .Lftrace_graph_caller, r0
+ jmp @r0
+ nop
+
+1:
+ mov.l .Lftrace_graph_entry, r6
+ mov.l .Lftrace_graph_entry_stub, r7
+ cmp/eq r6, r7
+ bt skip_trace
+
+ mov.l .Lftrace_graph_caller, r0
+ jmp @r0
+ nop
+
+ .align 2
+.Lftrace_graph_return:
+ .long ftrace_graph_return
+.Lftrace_graph_entry:
+ .long ftrace_graph_entry
+.Lftrace_graph_entry_stub:
+ .long ftrace_graph_entry_stub
+.Lftrace_graph_caller:
+ .long ftrace_graph_caller
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+ .globl skip_trace
skip_trace:
MCOUNT_LEAVE()
.align 2
.Lftrace_trace_function:
- .long ftrace_trace_function
+ .long ftrace_trace_function
#ifdef CONFIG_DYNAMIC_FTRACE
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * NOTE: Do not move either ftrace_graph_call or ftrace_caller
+ * as this will affect the calculation of GRAPH_INSN_OFFSET.
+ */
+ .globl ftrace_graph_call
+ftrace_graph_call:
+ mov.l .Lskip_trace, r0
+ jmp @r0
+ nop
+
+ .align 2
+.Lskip_trace:
+ .long skip_trace
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
.globl ftrace_caller
ftrace_caller:
mov.l .Lfunction_trace_stop, r0
@@ -73,6 +174,8 @@ ftrace_caller:
tst r0, r0
bf ftrace_stub
+ STACK_CHECK()
+
MCOUNT_ENTER()
.globl ftrace_call
@@ -81,7 +184,12 @@ ftrace_call:
jsr @r6
nop
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ bra ftrace_graph_call
+ nop
+#else
MCOUNT_LEAVE()
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
#endif /* CONFIG_DYNAMIC_FTRACE */
/*
@@ -100,6 +208,98 @@ ftrace_stub:
rts
nop
+#ifdef CONFIG_STACK_DEBUG
+ .globl stack_panic
+stack_panic:
+ mov.l .Ldump_stack, r0
+ jsr @r0
+ nop
+
+ mov.l .Lpanic, r0
+ jsr @r0
+ mov.l .Lpanic_s, r4
+
+ rts
+ nop
+
.align 2
.Lfunction_trace_stop:
.long function_trace_stop
+.L_ebss:
+ .long _ebss
+.L_init_thread_union:
+ .long init_thread_union
+.Lpanic:
+ .long panic
+.Lpanic_s:
+ .long .Lpanic_str
+.Ldump_stack:
+ .long dump_stack
+
+ .section .rodata
+ .align 2
+.Lpanic_str:
+ .string "Stack error"
+#endif /* CONFIG_STACK_DEBUG */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ .globl ftrace_graph_caller
+ftrace_graph_caller:
+ mov.l 2f, r0
+ mov.l @r0, r0
+ tst r0, r0
+ bt 1f
+
+ mov.l 3f, r1
+ jmp @r1
+ nop
+1:
+ /*
+ * MCOUNT_ENTER() pushed 5 registers onto the stack, so
+ * the stack address containing our return address is
+ * r15 + 20.
+ */
+ mov #20, r0
+ add r15, r0
+ mov r0, r4
+
+ mov.l .Lprepare_ftrace_return, r0
+ jsr @r0
+ nop
+
+ MCOUNT_LEAVE()
+
+ .align 2
+2: .long function_trace_stop
+3: .long skip_trace
+.Lprepare_ftrace_return:
+ .long prepare_ftrace_return
+
+ .globl return_to_handler
+return_to_handler:
+ /*
+ * Save the return values.
+ */
+ mov.l r0, @-r15
+ mov.l r1, @-r15
+
+ mov #0, r4
+
+ mov.l .Lftrace_return_to_handler, r0
+ jsr @r0
+ nop
+
+ /*
+ * The return value from ftrace_return_handler has the real
+ * address that we should return to.
+ */
+ lds r0, pr
+ mov.l @r15+, r1
+ rts
+ mov.l @r15+, r0
+
+
+ .align 2
+.Lftrace_return_to_handler:
+ .long ftrace_return_to_handler
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-08 03:48:39 +0000