From be7635e7287e0e8013af3c89a6354a9e0182594c Mon Sep 17 00:00:00 2001
From: Alexander Potapenko <glider@google.com>
Date: Fri, 25 Mar 2016 14:22:05 -0700
Subject: [PATCH] arch, ftrace: for KASAN put hard/soft IRQ entries into
separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/arm/include/asm/exception.h | 2 +-
arch/arm/kernel/vmlinux.lds.S | 1 +
arch/arm64/include/asm/exception.h | 2 +-
arch/arm64/kernel/vmlinux.lds.S | 1 +
arch/blackfin/kernel/vmlinux.lds.S | 1 +
arch/c6x/kernel/vmlinux.lds.S | 1 +
arch/metag/kernel/vmlinux.lds.S | 1 +
arch/microblaze/kernel/vmlinux.lds.S | 1 +
arch/mips/kernel/vmlinux.lds.S | 1 +
arch/nios2/kernel/vmlinux.lds.S | 1 +
arch/openrisc/kernel/vmlinux.lds.S | 1 +
arch/parisc/kernel/vmlinux.lds.S | 1 +
arch/powerpc/kernel/vmlinux.lds.S | 1 +
arch/s390/kernel/vmlinux.lds.S | 1 +
arch/sh/kernel/vmlinux.lds.S | 1 +
arch/sparc/kernel/vmlinux.lds.S | 1 +
arch/tile/kernel/vmlinux.lds.S | 1 +
arch/x86/kernel/vmlinux.lds.S | 1 +
include/asm-generic/vmlinux.lds.h | 12 +++++++++++-
include/linux/ftrace.h | 11 -----------
include/linux/interrupt.h | 20 ++++++++++++++++++++
kernel/softirq.c | 2 +-
kernel/trace/trace_functions_graph.c | 1 +
23 files changed, 51 insertions(+), 15 deletions(-)
diff --git a/arch/arm/include/asm/exception.h b/arch/arm/include/asm/exception.h
index 5abaf5bbd985f..bf1991263d2df 100644
--- a/arch/arm/include/asm/exception.h
+++ b/arch/arm/include/asm/exception.h
@@ -7,7 +7,7 @@
#ifndef __ASM_ARM_EXCEPTION_H
#define __ASM_ARM_EXCEPTION_H
-#include <linux/ftrace.h>
+#include <linux/interrupt.h>
#define __exception __attribute__((section(".exception.text")))
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 1fab979daeaf1..e2c6da096cefa 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -108,6 +108,7 @@ SECTIONS
*(.exception.text)
__exception_text_end = .;
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
TEXT_TEXT
SCHED_TEXT
LOCK_TEXT
diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h
index 6cb7e1a6bc02a..0c2eec490abf6 100644
--- a/arch/arm64/include/asm/exception.h
+++ b/arch/arm64/include/asm/exception.h
@@ -18,7 +18,7 @@
#ifndef __ASM_EXCEPTION_H
#define __ASM_EXCEPTION_H
-#include <linux/ftrace.h>
+#include <linux/interrupt.h>
#define __exception __attribute__((section(".exception.text")))
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 37f624df68fad..5a1939a74ff35 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -103,6 +103,7 @@ SECTIONS
*(.exception.text)
__exception_text_end = .;
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
TEXT_TEXT
SCHED_TEXT
LOCK_TEXT
diff --git a/arch/blackfin/kernel/vmlinux.lds.S b/arch/blackfin/kernel/vmlinux.lds.S
index c9eec84aa2586..d920b959ff3a4 100644
--- a/arch/blackfin/kernel/vmlinux.lds.S
+++ b/arch/blackfin/kernel/vmlinux.lds.S
@@ -35,6 +35,7 @@ SECTIONS
#endif
LOCK_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
KPROBES_TEXT
#ifdef CONFIG_ROMKERNEL
__sinittext = .;
diff --git a/arch/c6x/kernel/vmlinux.lds.S b/arch/c6x/kernel/vmlinux.lds.S
index 5a6e141d1641b..50bc10f97bcb4 100644
--- a/arch/c6x/kernel/vmlinux.lds.S
+++ b/arch/c6x/kernel/vmlinux.lds.S
@@ -72,6 +72,7 @@ SECTIONS
SCHED_TEXT
LOCK_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
KPROBES_TEXT
*(.fixup)
*(.gnu.warning)
diff --git a/arch/metag/kernel/vmlinux.lds.S b/arch/metag/kernel/vmlinux.lds.S
index e12055e88bfe5..150ace92c7ade 100644
--- a/arch/metag/kernel/vmlinux.lds.S
+++ b/arch/metag/kernel/vmlinux.lds.S
@@ -24,6 +24,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.text.*)
*(.gnu.warning)
}
diff --git a/arch/microblaze/kernel/vmlinux.lds.S b/arch/microblaze/kernel/vmlinux.lds.S
index be9488d697347..0a47f04105541 100644
--- a/arch/microblaze/kernel/vmlinux.lds.S
+++ b/arch/microblaze/kernel/vmlinux.lds.S
@@ -36,6 +36,7 @@ SECTIONS {
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
. = ALIGN (4) ;
_etext = . ;
}
diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index 0a93e83cd0147..54d653ee17e1a 100644
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -58,6 +58,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.text.*)
*(.fixup)
*(.gnu.warning)
diff --git a/arch/nios2/kernel/vmlinux.lds.S b/arch/nios2/kernel/vmlinux.lds.S
index 326fab40a9de0..e23e895399677 100644
--- a/arch/nios2/kernel/vmlinux.lds.S
+++ b/arch/nios2/kernel/vmlinux.lds.S
@@ -39,6 +39,7 @@ SECTIONS
SCHED_TEXT
LOCK_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
KPROBES_TEXT
} =0
_etext = .;
diff --git a/arch/openrisc/kernel/vmlinux.lds.S b/arch/openrisc/kernel/vmlinux.lds.S
index 2d69a853b742e..d936de4c07cad 100644
--- a/arch/openrisc/kernel/vmlinux.lds.S
+++ b/arch/openrisc/kernel/vmlinux.lds.S
@@ -50,6 +50,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.fixup)
*(.text.__*)
_etext = .;
diff --git a/arch/parisc/kernel/vmlinux.lds.S b/arch/parisc/kernel/vmlinux.lds.S
index 308f29081d461..f3ead0b6ce461 100644
--- a/arch/parisc/kernel/vmlinux.lds.S
+++ b/arch/parisc/kernel/vmlinux.lds.S
@@ -72,6 +72,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.text.do_softirq)
*(.text.sys_exit)
*(.text.do_sigaltstack)
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index d41fd0af89807..2dd91f79de05a 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -55,6 +55,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
#ifdef CONFIG_PPC32
*(.got1)
diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 445657fe658cc..0f41a82863785 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -28,6 +28,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.fixup)
*(.gnu.warning)
} :text = 0x0700
diff --git a/arch/sh/kernel/vmlinux.lds.S b/arch/sh/kernel/vmlinux.lds.S
index db88cbf9eafdc..235a4101999fe 100644
--- a/arch/sh/kernel/vmlinux.lds.S
+++ b/arch/sh/kernel/vmlinux.lds.S
@@ -39,6 +39,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.fixup)
*(.gnu.warning)
_etext = .; /* End of text section */
diff --git a/arch/sparc/kernel/vmlinux.lds.S b/arch/sparc/kernel/vmlinux.lds.S
index f1a2f688b28a3..aadd321aa05db 100644
--- a/arch/sparc/kernel/vmlinux.lds.S
+++ b/arch/sparc/kernel/vmlinux.lds.S
@@ -48,6 +48,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.gnu.warning)
} = 0
_etext = .;
diff --git a/arch/tile/kernel/vmlinux.lds.S b/arch/tile/kernel/vmlinux.lds.S
index 0e059a0101ea3..378f5d8d1ec8a 100644
--- a/arch/tile/kernel/vmlinux.lds.S
+++ b/arch/tile/kernel/vmlinux.lds.S
@@ -45,6 +45,7 @@ SECTIONS
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
__fix_text_end = .; /* tile-cpack won't rearrange before this */
ALIGN_FUNCTION();
*(.hottext*)
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index d239639e0c1dd..4c941f88d405f 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -101,6 +101,7 @@ SECTIONS
KPROBES_TEXT
ENTRY_TEXT
IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
*(.fixup)
*(.gnu.warning)
/* End of text section */
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 8f5a12ab2f2b9..339125bb4d2cf 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -456,7 +456,7 @@
*(.entry.text) \
VMLINUX_SYMBOL(__entry_text_end) = .;
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+#if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
#define IRQENTRY_TEXT \
ALIGN_FUNCTION(); \
VMLINUX_SYMBOL(__irqentry_text_start) = .; \
@@ -466,6 +466,16 @@
#define IRQENTRY_TEXT
#endif
+#if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
+#define SOFTIRQENTRY_TEXT \
+ ALIGN_FUNCTION(); \
+ VMLINUX_SYMBOL(__softirqentry_text_start) = .; \
+ *(.softirqentry.text) \
+ VMLINUX_SYMBOL(__softirqentry_text_end) = .;
+#else
+#define SOFTIRQENTRY_TEXT
+#endif
+
/* Section used for early init (in .S files) */
#define HEAD_TEXT *(.head.text)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 6d9df3f7e334c..dea12a6e413bc 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -811,16 +811,6 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
*/
#define __notrace_funcgraph notrace
-/*
- * We want to which function is an entrypoint of a hardirq.
- * That will help us to put a signal on output.
- */
-#define __irq_entry __attribute__((__section__(".irqentry.text")))
-
-/* Limits of hardirq entrypoints */
-extern char __irqentry_text_start[];
-extern char __irqentry_text_end[];
-
#define FTRACE_NOTRACE_DEPTH 65536
#define FTRACE_RETFUNC_DEPTH 50
#define FTRACE_RETSTACK_ALLOC_SIZE 32
@@ -857,7 +847,6 @@ static inline void unpause_graph_tracing(void)
#else /* !CONFIG_FUNCTION_GRAPH_TRACER */
#define __notrace_funcgraph
-#define __irq_entry
#define INIT_FTRACE_GRAPH
static inline void ftrace_graph_init_task(struct task_struct *t) { }
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 358076eda364e..9fcabeb07787b 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -683,4 +683,24 @@ extern int early_irq_init(void);
extern int arch_probe_nr_irqs(void);
extern int arch_early_irq_init(void);
+#if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
+/*
+ * We want to know which function is an entrypoint of a hardirq or a softirq.
+ */
+#define __irq_entry __attribute__((__section__(".irqentry.text")))
+#define __softirq_entry \
+ __attribute__((__section__(".softirqentry.text")))
+
+/* Limits of hardirq entrypoints */
+extern char __irqentry_text_start[];
+extern char __irqentry_text_end[];
+/* Limits of softirq entrypoints */
+extern char __softirqentry_text_start[];
+extern char __softirqentry_text_end[];
+
+#else
+#define __irq_entry
+#define __softirq_entry
+#endif
+
#endif
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 8aae49dd7da86..17caf4b63342d 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -227,7 +227,7 @@ static inline bool lockdep_softirq_start(void) { return false; }
static inline void lockdep_softirq_end(bool in_hardirq) { }
#endif
-asmlinkage __visible void __do_softirq(void)
+asmlinkage __visible void __softirq_entry __do_softirq(void)
{
unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
unsigned long old_flags = current->flags;
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 91d6a63a2ea76..3a0244ff7ea8d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -8,6 +8,7 @@
*/
#include <linux/uaccess.h>
#include <linux/ftrace.h>
+#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/fs.h>
--
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