| Message ID | 1561973757-5445-1-git-send-email-anshuman.khandual@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [DRAFT] mm/kprobes: Add generic kprobe_fault_handler() fallback definition | expand |
On 7/1/19 2:35 AM, Anshuman Khandual wrote: > 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(). > > Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> > --- > I am planning to go with approach unless we just want to implement a stub > definition for parisc to get around the build problem for now. > > Hello Guenter, > > Could you please test this in your parisc setup. Thank you. > With this patch applied on top of next-20190628, parisc:allmodconfig builds correctly. I scheduled a full build for tonight for all architectures. Guenter > - Anshuman > > 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 */ >
On 07/01/2019 06:58 PM, Guenter Roeck wrote: > On 7/1/19 2:35 AM, Anshuman Khandual wrote: >> 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(). >> >> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> >> --- >> I am planning to go with approach unless we just want to implement a stub >> definition for parisc to get around the build problem for now. >> >> Hello Guenter, >> >> Could you please test this in your parisc setup. Thank you. >> > > With this patch applied on top of next-20190628, parisc:allmodconfig builds > correctly. I scheduled a full build for tonight for all architectures. How did that come along ? Did this pass all build tests ?
On 7/2/19 10:35 PM, Anshuman Khandual wrote: > > > On 07/01/2019 06:58 PM, Guenter Roeck wrote: >> On 7/1/19 2:35 AM, Anshuman Khandual wrote: >>> 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(). >>> >>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> >>> --- >>> I am planning to go with approach unless we just want to implement a stub >>> definition for parisc to get around the build problem for now. >>> >>> Hello Guenter, >>> >>> Could you please test this in your parisc setup. Thank you. >>> >> >> With this patch applied on top of next-20190628, parisc:allmodconfig builds >> correctly. I scheduled a full build for tonight for all architectures. > > How did that come along ? Did this pass all build tests ? > Let's say it didn't find any failures related to this patch. I built on top of next-20190701 which was quite badly broken for other reasons. Unfortunately, next-20190702 is much worse, so retesting would not add any value at this time. I'd say go for it. Guenter
On 07/03/2019 06:29 PM, Guenter Roeck wrote: > On 7/2/19 10:35 PM, Anshuman Khandual wrote: >> >> >> On 07/01/2019 06:58 PM, Guenter Roeck wrote: >>> On 7/1/19 2:35 AM, Anshuman Khandual wrote: >>>> 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(). >>>> >>>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> >>>> --- >>>> I am planning to go with approach unless we just want to implement a stub >>>> definition for parisc to get around the build problem for now. >>>> >>>> Hello Guenter, >>>> >>>> Could you please test this in your parisc setup. Thank you. >>>> >>> >>> With this patch applied on top of next-20190628, parisc:allmodconfig builds >>> correctly. I scheduled a full build for tonight for all architectures. >> >> How did that come along ? Did this pass all build tests ? >> > > Let's say it didn't find any failures related to this patch. I built on top of > next-20190701 which was quite badly broken for other reasons. Unfortunately, > next-20190702 is much worse, so retesting would not add any value at this time. > I'd say go for it. > > Guenter > Sure thanks, will post it out soon.
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 */
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(). Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> --- I am planning to go with approach unless we just want to implement a stub definition for parisc to get around the build problem for now. Hello Guenter, Could you please test this in your parisc setup. Thank you. - Anshuman 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(-)