[PATCH] arm64,trace: Add page fault traceponits
sunliming
sunliming at kylinos.cn
Wed Apr 20 00:01:09 PDT 2022
The arm64 architecture lacks some tracepoints support, this patch
adds page fault tracepoints. The code and arch policy is mainly
inherited from x86.
Experimented on my centos8 virtual machine:
dracut:/# echo 1 > /sys/kernel/tracing/events/exceptions/enable
dracut:/# cat /sys/kernel/tracing/trace
The results:
sh-6098 [001] ..... 1186.024675: page_fault_user: addr=0xffffe153cc00 pc=0xffffa4117338 esr=0xffffe153cc00
cat-6126 [000] ..... 1186.024677: page_fault_kernel: addr=0xffffa4323740 pc=schedule_tail esr=0xffffa4323740
sh-6098 [001] ..... 1186.026085: page_fault_user: addr=0xaaaad23fae34 pc=0xaaaad231c0fc esr=0xaaaad23fae34
cat-6126 [000] ..... 1186.026106: page_fault_user: addr=0xffffa414565c pc=0xffffa414565c esr=0xffffa414565c
cat-6126 [000] ..... 1186.026222: page_fault_user: addr=0xffffa4214e10 pc=0xffffa4145670 esr=0xffffa4214e10
cat-6126 [000] ..... 1186.026243: page_fault_user: addr=0xffffa420fd88 pc=0xffffa41456ac esr=0xffffa420fd88
cat-6126 [000] ..... 1186.026282: page_fault_user: addr=0xffffa4117338 pc=0xffffa4117338 esr=0xffffa4117338
cat-6126 [000] ..... 1186.026308: page_fault_user: addr=0xffffe153cc00 pc=0xffffa4117338 esr=0xffffe153cc00
cat-6126 [000] ..... 1186.026365: page_fault_user: addr=0xaaaad231bd84 pc=0xaaaad231bd84 esr=0xaaaad231bd84
sh-6098 [001] ..... 1186.026372: page_fault_user: addr=0xaaab04330098 pc=0xffffa411be68 esr=0xaaab04330098
cat-6126 [000] ..... 1186.026394: page_fault_user: addr=0xaaaad22ef420 pc=0xaaaad22ef420 esr=0xaaaad22ef420
cat-6126 [000] ..... 1186.026414: page_fault_user: addr=0xaaaad23ee9b0 pc=0xaaaad22ef424 esr=0xaaaad23ee9b0
cat-6126 [000] ..... 1186.026426: page_fault_user: addr=0xffffa40c3110 pc=0xffffa40c3110 esr=0xffffa40c3110
cat-6126 [000] ..... 1186.026450: page_fault_user: addr=0xaaaad22f23f8 pc=0xaaaad22f23f8 esr=0xaaaad22f23f8
cat-6126 [000] ..... 1186.026467: page_fault_user: addr=0xaaaad23f0030 pc=0xaaaad22f240c esr=0xaaaad23f0030
cat-6126 [000] ..... 1186.026481: page_fault_user: addr=0xaaaad23fae3c pc=0xaaaad231be40 esr=0xaaaad23fae3c
cat-6126 [000] ..... 1186.026530: page_fault_user: addr=0xffffa40d63d8 pc=0xffffa40d63d8 esr=0xffffa40d63d8
cat-6126 [000] ..... 1186.026554: page_fault_user: addr=0xffffa431f650 pc=0xffffa40d63f8 esr=0xffffa431f650
sh-6098 [001] ..... 1186.026556: page_fault_user: addr=0xaaab04358d28 pc=0xffffa411be70 esr=0xaaab04358d28
cat-6126 [000] ..... 1186.026571: page_fault_user: addr=0xaaaad24015d0 pc=0xffffa40d640c esr=0xaaaad24015d0
cat-6126 [000] ..... 1186.026600: page_fault_user: addr=0xaaaad2332be8 pc=0xaaaad2332be8 esr=0xaaaad2332be8
cat-6126 [000] ..... 1186.026703: page_fault_user: addr=0xffffa416c438 pc=0xffffa416c438 esr=0xffffa416c438
sh-6098 [001] ..... 1186.026749: page_fault_user: addr=0xaaab04369d70 pc=0xffffa41193d8 esr=0xaaab04369d70
cat-6126 [000] ..... 1186.027610: page_fault_user: addr=0xaaaad2307754 pc=0xaaaad2307754 esr=0xaaaad2307754
cat-6126 [000] ..... 1186.027711: page_fault_user: addr=0xaaaad24014c4 pc=0xaaaad23310e4 esr=0xaaaad24014c4
cat-6126 [000] ..... 1186.027892: page_fault_user: addr=0xaaab04359a80 pc=0xaaaad23052f0 esr=0xaaab04359a80
cat-6126 [000] ..... 1186.027916: page_fault_user: addr=0xaaaad236cf80 pc=0xaaaad236cf80 esr=0xaaaad236cf80
Signed-off-by: sunliming <sunliming at kylinos.cn>
---
arch/arm64/include/asm/trace/common.h | 12 +++++
arch/arm64/include/asm/trace/exceptions.h | 54 +++++++++++++++++++++++
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/tracepoint.c | 24 ++++++++++
arch/arm64/mm/Makefile | 3 ++
arch/arm64/mm/fault.c | 19 ++++++++
6 files changed, 113 insertions(+)
create mode 100644 arch/arm64/include/asm/trace/common.h
create mode 100644 arch/arm64/include/asm/trace/exceptions.h
create mode 100644 arch/arm64/kernel/tracepoint.c
diff --git a/arch/arm64/include/asm/trace/common.h b/arch/arm64/include/asm/trace/common.h
new file mode 100644
index 000000000000..f0f9bcdb74d9
--- /dev/null
+++ b/arch/arm64/include/asm/trace/common.h
@@ -0,0 +1,12 @@
+#ifndef _ASM_TRACE_COMMON_H
+#define _ASM_TRACE_COMMON_H
+
+#ifdef CONFIG_TRACING
+DECLARE_STATIC_KEY_FALSE(trace_pagefault_key);
+#define trace_pagefault_enabled() \
+ static_branch_unlikely(&trace_pagefault_key)
+#else
+static inline bool trace_pagefault_enabled(void) { return false; }
+#endif
+
+#endif
diff --git a/arch/arm64/include/asm/trace/exceptions.h b/arch/arm64/include/asm/trace/exceptions.h
new file mode 100644
index 000000000000..b0309aeca50b
--- /dev/null
+++ b/arch/arm64/include/asm/trace/exceptions.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM exceptions
+
+#if !defined(_TRACE_PAGE_FAULT_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_PAGE_FAULT_H
+
+#include <linux/tracepoint.h>
+#include <asm/trace/common.h>
+
+extern int trace_pagefault_reg(void);
+extern void trace_pagefault_unreg(void);
+
+DECLARE_EVENT_CLASS(arm64_exceptions,
+
+ TP_PROTO(unsigned long addr, struct pt_regs *regs,
+ unsigned int esr),
+
+ TP_ARGS(addr, regs, esr),
+
+ TP_STRUCT__entry(
+ __field(unsigned long, addr)
+ __field(unsigned long, pc)
+ __field(unsigned int, esr)
+ ),
+
+ TP_fast_assign(
+ __entry->addr = addr;
+ __entry->pc = regs->pc;
+ __entry->esr = esr;
+ ),
+
+ TP_printk("addr=%ps pc=%ps esr=0x%lx",
+ (void *)__entry->addr, (void *)__entry->pc,
+ __entry->addr));
+
+#define DEFINE_PAGE_FAULT_EVENT(name) \
+DEFINE_EVENT_FN(arm64_exceptions, name, \
+ TP_PROTO(unsigned long addr, struct pt_regs *regs, \
+ unsigned int esr), \
+ TP_ARGS(addr, regs, esr), \
+ trace_pagefault_reg, trace_pagefault_unreg);
+
+DEFINE_PAGE_FAULT_EVENT(page_fault_user);
+DEFINE_PAGE_FAULT_EVENT(page_fault_kernel);
+
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE exceptions
+#endif /* _TRACE_PAGE_FAULT_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 986837d7ec82..538476d91894 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o
obj-$(CONFIG_ARM64_MTE) += mte.o
obj-y += vdso-wrap.o
obj-$(CONFIG_COMPAT_VDSO) += vdso32-wrap.o
+obj-$(CONFIG_TRACING) += tracepoint.o
obj-y += probes/
head-y := head.o
diff --git a/arch/arm64/kernel/tracepoint.c b/arch/arm64/kernel/tracepoint.c
new file mode 100644
index 000000000000..ea36aa37a885
--- /dev/null
+++ b/arch/arm64/kernel/tracepoint.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Code for supporting page fault tracepoints.
+ *
+ *
+ */
+#include <linux/jump_label.h>
+#include <linux/atomic.h>
+
+#include <asm/trace/exceptions.h>
+
+DEFINE_STATIC_KEY_FALSE(trace_pagefault_key);
+
+int trace_pagefault_reg(void)
+{
+ static_branch_inc(&trace_pagefault_key);
+ return 0;
+}
+
+void trace_pagefault_unreg(void)
+{
+ static_branch_dec(&trace_pagefault_key);
+}
+
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index ff1e800ba7a1..62fef44062fa 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
+
obj-y := dma-mapping.o extable.o fault.o init.o \
cache.o copypage.o flush.o \
ioremap.o mmap.o pgd.o mmu.o \
@@ -12,5 +13,7 @@ obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o
obj-$(CONFIG_ARM64_MTE) += mteswap.o
KASAN_SANITIZE_physaddr.o += n
+CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace
+
obj-$(CONFIG_KASAN) += kasan_init.o
KASAN_SANITIZE_kasan_init.o := n
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 77341b160aca..5898d18ee20c 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -42,6 +42,9 @@
#include <asm/tlbflush.h>
#include <asm/traps.h>
+#define CREATE_TRACE_POINTS
+#include <asm/trace/exceptions.h>
+
struct fault_info {
int (*fn)(unsigned long far, unsigned int esr,
struct pt_regs *regs);
@@ -515,6 +518,20 @@ static bool is_write_abort(unsigned int esr)
return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
}
+static __always_inline void
+trace_page_fault_entries(struct pt_regs *regs, unsigned int esr,
+ unsigned long addr)
+{
+ if (!trace_pagefault_enabled())
+ return;
+
+ if (user_mode(regs))
+ trace_page_fault_user(addr, regs, esr);
+ else
+ trace_page_fault_kernel(addr, regs, esr);
+}
+
+
static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
struct pt_regs *regs)
{
@@ -525,6 +542,8 @@ static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
unsigned int mm_flags = FAULT_FLAG_DEFAULT;
unsigned long addr = untagged_addr(far);
+ trace_page_fault_entries(regs, esr, addr);
+
if (kprobe_page_fault(regs, esr))
return 0;
--
2.25.1
No virus found
Checked by Hillstone Network AntiVirus
More information about the linux-arm-kernel
mailing list