Architectures like parisc enable CONFIG_KROBES without having a definition
for kprobe_fault_handler() which results in a build failure. Arch needs to
provide kprobe_fault_handler() as it is platform specific and cannot have
a generic working alternative. But in the event when platform lacks such a
definition there needs to be a fallback.
This adds a stub kprobe_fault_handler() definition which not only prevents
a build failure but also makes sure that kprobe_page_fault() if called will
always return negative in absence of a sane platform specific alternative.
While here wrap kprobe_page_fault() in CONFIG_KPROBES. This enables stud
definitions for generic kporbe_fault_handler() and kprobes_built_in() can
just be dropped. Only on x86 it needs to be added back locally as it gets
used in a !CONFIG_KPROBES function do_general_protection().
Cc: Vineet Gupta <vgu...@synopsys.com>
Cc: Russell King <li...@armlinux.org.uk>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: Will Deacon <w...@kernel.org>
Cc: Tony Luck <tony.l...@intel.com>
Cc: Fenghua Yu <fenghua...@intel.com>
Cc: Ralf Baechle <r...@linux-mips.org>
Cc: Paul Burton <paul.bur...@mips.com>
Cc: James Hogan <jho...@kernel.org>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Heiko Carstens <heiko.carst...@de.ibm.com>
Cc: Vasily Gorbik <g...@linux.ibm.com>
Cc: Christian Borntraeger <borntrae...@de.ibm.com>
Cc: Yoshinori Sato <ys...@users.sourceforge.jp>
Cc: Rich Felker <dal...@libc.org>
Cc: "David S. Miller" <da...@davemloft.net>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: "Naveen N. Rao" <naveen.n....@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamur...@intel.com>
Cc: Masami Hiramatsu <mhira...@kernel.org>
Cc: Allison Randal <alli...@lohutok.net>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Enrico Weigelt <i...@metux.net>
Cc: Richard Fontana <rfont...@redhat.com>
Cc: Kate Stewart <kstew...@linuxfoundation.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Guenter Roeck <li...@roeck-us.net>
Cc: x...@kernel.org
Cc: linux-snps-...@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-i...@vger.kernel.org
Cc: linux-m...@vger.kernel.org
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux-s...@vger.kernel.org
Cc: linux...@vger.kernel.org
Cc: sparcli...@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com>
---
arch/arc/include/asm/kprobes.h | 1 +
arch/arm/include/asm/kprobes.h | 1 +
arch/arm64/include/asm/kprobes.h | 1 +
arch/ia64/include/asm/kprobes.h | 1 +
arch/mips/include/asm/kprobes.h | 1 +
arch/powerpc/include/asm/kprobes.h | 1 +
arch/s390/include/asm/kprobes.h | 1 +
arch/sh/include/asm/kprobes.h | 1 +
arch/sparc/include/asm/kprobes.h | 1 +
arch/x86/include/asm/kprobes.h | 6 ++++++
include/linux/kprobes.h | 32 ++++++++++++++++++------------
11 files changed, 34 insertions(+), 13 deletions(-)
diff --git a/arch/arc/include/asm/kprobes.h b/arch/arc/include/asm/kprobes.h
index 2134721dce44..ee8efe256675 100644
--- a/arch/arc/include/asm/kprobes.h
+++ b/arch/arc/include/asm/kprobes.h
@@ -45,6 +45,7 @@ struct kprobe_ctlblk {
struct prev_kprobe prev_kprobe;
};
+#define kprobe_fault_handler kprobe_fault_handler
int kprobe_fault_handler(struct pt_regs *regs, unsigned long cause);
void kretprobe_trampoline(void);
void trap_is_kprobe(unsigned long address, struct pt_regs *regs);
diff --git a/arch/arm/include/asm/kprobes.h b/arch/arm/include/asm/kprobes.h
index 213607a1f45c..660f877b989f 100644
--- a/arch/arm/include/asm/kprobes.h
+++ b/arch/arm/include/asm/kprobes.h
@@ -38,6 +38,7 @@ struct kprobe_ctlblk {
struct prev_kprobe prev_kprobe;
};
+#define kprobe_fault_handler kprobe_fault_handler
void arch_remove_kprobe(struct kprobe *);
int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
int kprobe_exceptions_notify(struct notifier_block *self,
diff --git a/arch/arm64/include/asm/kprobes.h b/arch/arm64/include/asm/kprobes.h
index 97e511d645a2..667773f75616 100644
--- a/arch/arm64/include/asm/kprobes.h
+++ b/arch/arm64/include/asm/kprobes.h
@@ -42,6 +42,7 @@ struct kprobe_ctlblk {
struct kprobe_step_ctx ss_ctx;
};
+#define kprobe_fault_handler kprobe_fault_handler
void arch_remove_kprobe(struct kprobe *);
int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
int kprobe_exceptions_notify(struct notifier_block *self,
diff --git a/arch/ia64/include/asm/kprobes.h b/arch/ia64/include/asm/kprobes.h
index c5cf5e4fb338..c321e8585089 100644
--- a/arch/ia64/include/asm/kprobes.h
+++ b/arch/ia64/include/asm/kprobes.h
@@ -106,6 +106,7 @@ struct arch_specific_insn {
unsigned short slot;
};
+#define kprobe_fault_handler kprobe_fault_handler
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
diff --git a/arch/mips/include/asm/kprobes.h b/arch/mips/include/asm/kprobes.h
index 68b1e5d458cf..d1efe991ea22 100644
--- a/arch/mips/include/asm/kprobes.h
+++ b/arch/mips/include/asm/kprobes.h
@@ -40,6 +40,7 @@ do {
\
#define kretprobe_blacklist_size 0
+#define kprobe_fault_handler kprobe_fault_handler
void arch_remove_kprobe(struct kprobe *p);
int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
diff --git a/arch/powerpc/include/asm/kprobes.h
b/arch/powerpc/include/asm/kprobes.h
index 66b3f2983b22..c94f375ec957 100644
--- a/arch/powerpc/include/asm/kprobes.h
+++ b/arch/powerpc/include/asm/kprobes.h
@@ -84,6 +84,7 @@ struct arch_optimized_insn {
kprobe_opcode_t *insn;
};
+#define kprobe_fault_handler kprobe_fault_handler
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
diff --git a/arch/s390/include/asm/kprobes.h b/arch/s390/include/asm/kprobes.h
index b106aa29bf55..0ecaebb78092 100644
--- a/arch/s390/include/asm/kprobes.h
+++ b/arch/s390/include/asm/kprobes.h
@@ -73,6 +73,7 @@ struct kprobe_ctlblk {
void arch_remove_kprobe(struct kprobe *p);
void kretprobe_trampoline(void);
+#define kprobe_fault_handler kprobe_fault_handler
int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
diff --git a/arch/sh/include/asm/kprobes.h b/arch/sh/include/asm/kprobes.h
index 6171682f7798..637a698393c0 100644
--- a/arch/sh/include/asm/kprobes.h
+++ b/arch/sh/include/asm/kprobes.h
@@ -45,6 +45,7 @@ struct kprobe_ctlblk {
struct prev_kprobe prev_kprobe;
};
+#define kprobe_fault_handler kprobe_fault_handler
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
diff --git a/arch/sparc/include/asm/kprobes.h b/arch/sparc/include/asm/kprobes.h
index bfcaa6326c20..9aa4d25a45a8 100644
--- a/arch/sparc/include/asm/kprobes.h
+++ b/arch/sparc/include/asm/kprobes.h
@@ -47,6 +47,7 @@ struct kprobe_ctlblk {
struct prev_kprobe prev_kprobe;
};
+#define kprobe_fault_handler kprobe_fault_handler
int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
diff --git a/arch/x86/include/asm/kprobes.h b/arch/x86/include/asm/kprobes.h
index 5dc909d9ad81..1af2b6db13bd 100644
--- a/arch/x86/include/asm/kprobes.h
+++ b/arch/x86/include/asm/kprobes.h
@@ -101,11 +101,17 @@ struct kprobe_ctlblk {
struct prev_kprobe prev_kprobe;
};
+#define kprobe_fault_handler kprobe_fault_handler
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
extern int kprobe_int3_handler(struct pt_regs *regs);
extern int kprobe_debug_handler(struct pt_regs *regs);
+#else
+static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
+{
+ return 0;
+}
#endif /* CONFIG_KPROBES */
#endif /* _ASM_X86_KPROBES_H */
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 04bdaf01112c..e106f3018804 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -182,11 +182,19 @@ DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
/*
* For #ifdef avoidance:
*/
-static inline int kprobes_built_in(void)
+
+/*
+ * Architectures need to override this with their own implementation
+ * if they care to call kprobe_page_fault(). This will just ensure
+ * that kprobe_page_fault() returns false when called without having
+ * a proper platform specific definition for kprobe_fault_handler().
+ */
+#ifndef kprobe_fault_handler
+static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
{
- return 1;
+ return 0;
}
-
+#endif
#ifdef CONFIG_KRETPROBES
extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs);
@@ -375,14 +383,6 @@ void free_insn_page(void *page);
#else /* !CONFIG_KPROBES: */
-static inline int kprobes_built_in(void)
-{
- return 0;
-}
-static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
-{
- return 0;
-}
static inline struct kprobe *get_kprobe(void *addr)
{
return NULL;
@@ -458,12 +458,11 @@ static inline bool is_kprobe_optinsn_slot(unsigned long
addr)
}
#endif
+#ifdef CONFIG_KPROBES
/* Returns true if kprobes handled the fault */
static nokprobe_inline bool kprobe_page_fault(struct pt_regs *regs,
unsigned int trap)
{
- if (!kprobes_built_in())
- return false;
if (user_mode(regs))
return false;
/*
@@ -476,5 +475,12 @@ static nokprobe_inline bool kprobe_page_fault(struct
pt_regs *regs,
return false;
return kprobe_fault_handler(regs, trap);
}
+#else
+static nokprobe_inline bool kprobe_page_fault(struct pt_regs *regs,
+ unsigned int trap)
+{
+ return false;
+}
+#endif
#endif /* _LINUX_KPROBES_H */
--
2.20.1
