Linux-Kernel Archive: Re: [PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation Re: [PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation From: Masami Hiramatsu Date: Thu May 05 2022 - 21:45:24 EST Next message: Rex-BC Chen: "Re: [PATCH v6 05/10] cpufreq: mediatek: Add opp notification support" Previous message: Peng Liu: "[PATCH 2/2] null_blk: fix wrong use of nr_online_nodes" In reply to: Tiezhu Yang: "[PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation" Next in thread: Tiezhu Yang: "Re: [PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation" Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] On Thu, 5 May 2022 20:19:08 +0800 Tiezhu Yang wrote: > If define CONFIG_KPROBES, __kprobes annotation forces the whole function > into the ".kprobes.text" section, NOKPROBE_SYMBOL() just stores the given > function address in the "_kprobe_blacklist" section which is introduced > to maintain kprobes blacklist. > > Modify the related code to use NOKPROBE_SYMBOL() to protect functions from > kprobes instead of __kprobes annotation under arch/mips. So you added some non '__kprobes' annotated functions to NOKPROBE_SYMBOL() in this patch. Those caused the kernel panic, right? If so, please add such comment on this description too. Or, split this into 2 patches, one fixes the kernel panic by adding those functions to NOKPROBE_SYMBOL() and the other is replacing __kprobes with NOKPROBE_SYMBOL(). Also, could you also find the commit which introduces the kernel panic? It is worth to backport such fix to stable trees. Thank you, > > Signed-off-by: Tiezhu Yang > --- > arch/mips/kernel/kprobes.c | 45 ++++++++++++++++++++++++++++++++------------- > arch/mips/mm/fault.c | 6 ++++-- > 2 files changed, 36 insertions(+), 15 deletions(-) > > diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c > index 6c7f3b1..21f9cec 100644 > --- a/arch/mips/kernel/kprobes.c > +++ b/arch/mips/kernel/kprobes.c > @@ -44,10 +44,11 @@ static const union mips_instruction breakpoint2_insn = { > DEFINE_PER_CPU(struct kprobe *, current_kprobe); > DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); > > -static int __kprobes insn_has_delayslot(union mips_instruction insn) > +static int insn_has_delayslot(union mips_instruction insn) > { > return __insn_has_delay_slot(insn); > } > +NOKPROBE_SYMBOL(insn_has_delayslot); > > /* > * insn_has_ll_or_sc function checks whether instruction is ll or sc > @@ -56,7 +57,7 @@ static int __kprobes insn_has_delayslot(union mips_instruction insn) > * instructions; cannot do much about breakpoint in the middle of > * ll/sc pair; it is upto user to avoid those places > */ > -static int __kprobes insn_has_ll_or_sc(union mips_instruction insn) > +static int insn_has_ll_or_sc(union mips_instruction insn) > { > int ret = 0; > > @@ -72,8 +73,9 @@ static int __kprobes insn_has_ll_or_sc(union mips_instruction insn) > } > return ret; > } > +NOKPROBE_SYMBOL(insn_has_ll_or_sc); > > -int __kprobes arch_prepare_kprobe(struct kprobe *p) > +int arch_prepare_kprobe(struct kprobe *p) > { > union mips_instruction insn; > union mips_instruction prev_insn; > @@ -132,26 +134,30 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) > out: > return ret; > } > +NOKPROBE_SYMBOL(arch_prepare_kprobe); > > -void __kprobes arch_arm_kprobe(struct kprobe *p) > +void arch_arm_kprobe(struct kprobe *p) > { > *p->addr = breakpoint_insn; > flush_insn_slot(p); > } > +NOKPROBE_SYMBOL(arch_arm_kprobe); > > -void __kprobes arch_disarm_kprobe(struct kprobe *p) > +void arch_disarm_kprobe(struct kprobe *p) > { > *p->addr = p->opcode; > flush_insn_slot(p); > } > +NOKPROBE_SYMBOL(arch_disarm_kprobe); > > -void __kprobes arch_remove_kprobe(struct kprobe *p) > +void arch_remove_kprobe(struct kprobe *p) > { > if (p->ainsn.insn) { > free_insn_slot(p->ainsn.insn, 0); > p->ainsn.insn = NULL; > } > } > +NOKPROBE_SYMBOL(arch_remove_kprobe); > > static void save_previous_kprobe(struct kprobe_ctlblk *kcb) > { > @@ -161,6 +167,7 @@ static void save_previous_kprobe(struct kprobe_ctlblk *kcb) > kcb->prev_kprobe.saved_SR = kcb->kprobe_saved_SR; > kcb->prev_kprobe.saved_epc = kcb->kprobe_saved_epc; > } > +NOKPROBE_SYMBOL(save_previous_kprobe); > > static void restore_previous_kprobe(struct kprobe_ctlblk *kcb) > { > @@ -170,6 +177,7 @@ static void restore_previous_kprobe(struct kprobe_ctlblk *kcb) > kcb->kprobe_saved_SR = kcb->prev_kprobe.saved_SR; > kcb->kprobe_saved_epc = kcb->prev_kprobe.saved_epc; > } > +NOKPROBE_SYMBOL(restore_previous_kprobe); > > static void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, > struct kprobe_ctlblk *kcb) > @@ -178,6 +186,7 @@ static void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, > kcb->kprobe_saved_SR = kcb->kprobe_old_SR = (regs->cp0_status & ST0_IE); > kcb->kprobe_saved_epc = regs->cp0_epc; > } > +NOKPROBE_SYMBOL(set_current_kprobe); > > /** > * evaluate_branch_instrucion - > @@ -225,6 +234,7 @@ static int evaluate_branch_instruction(struct kprobe *p, struct pt_regs *regs, > return -EFAULT; > > } > +NOKPROBE_SYMBOL(evaluate_branch_instruction); > > static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, > struct kprobe_ctlblk *kcb) > @@ -244,6 +254,7 @@ static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, > } > regs->cp0_epc = (unsigned long)&p->ainsn.insn[0]; > } > +NOKPROBE_SYMBOL(prepare_singlestep); > > /* > * Called after single-stepping. p->addr is the address of the > @@ -257,7 +268,7 @@ static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, > * breakpoint trap. In case of branch instructions, the target > * epc to be restored. > */ > -static void __kprobes resume_execution(struct kprobe *p, > +static void resume_execution(struct kprobe *p, > struct pt_regs *regs, > struct kprobe_ctlblk *kcb) > { > @@ -268,8 +279,9 @@ static void __kprobes resume_execution(struct kprobe *p, > regs->cp0_epc = orig_epc + 4; > } > } > +NOKPROBE_SYMBOL(resume_execution); > > -static int __kprobes kprobe_handler(struct pt_regs *regs) > +static int kprobe_handler(struct pt_regs *regs) > { > struct kprobe *p; > int ret = 0; > @@ -367,8 +379,9 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) > return ret; > > } > +NOKPROBE_SYMBOL(kprobe_handler); > > -static inline int post_kprobe_handler(struct pt_regs *regs) > +static int post_kprobe_handler(struct pt_regs *regs) > { > struct kprobe *cur = kprobe_running(); > struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); > @@ -396,6 +409,7 @@ static inline int post_kprobe_handler(struct pt_regs *regs) > > return 1; > } > +NOKPROBE_SYMBOL(post_kprobe_handler); > > int kprobe_fault_handler(struct pt_regs *regs, int trapnr) > { > @@ -411,11 +425,12 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr) > } > return 0; > } > +NOKPROBE_SYMBOL(kprobe_fault_handler); > > /* > * Wrapper routine for handling exceptions. > */ > -int __kprobes kprobe_exceptions_notify(struct notifier_block *self, > +int kprobe_exceptions_notify(struct notifier_block *self, > unsigned long val, void *data) > { > > @@ -446,6 +461,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, > } > return ret; > } > +NOKPROBE_SYMBOL(kprobe_exceptions_notify); > > /* > * Function return probe trampoline: > @@ -469,7 +485,7 @@ static void __used kretprobe_trampoline_holder(void) > > void __kretprobe_trampoline(void); > > -void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, > +void arch_prepare_kretprobe(struct kretprobe_instance *ri, > struct pt_regs *regs) > { > ri->ret_addr = (kprobe_opcode_t *) regs->regs[31]; > @@ -478,11 +494,12 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, > /* Replace the return addr with trampoline addr */ > regs->regs[31] = (unsigned long)__kretprobe_trampoline; > } > +NOKPROBE_SYMBOL(arch_prepare_kretprobe); > > /* > * Called when the probe at kretprobe trampoline is hit > */ > -static int __kprobes trampoline_probe_handler(struct kprobe *p, > +static int trampoline_probe_handler(struct kprobe *p, > struct pt_regs *regs) > { > instruction_pointer(regs) = __kretprobe_trampoline_handler(regs, NULL); > @@ -493,14 +510,16 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p, > */ > return 1; > } > +NOKPROBE_SYMBOL(trampoline_probe_handler); > > -int __kprobes arch_trampoline_kprobe(struct kprobe *p) > +int arch_trampoline_kprobe(struct kprobe *p) > { > if (p->addr == (kprobe_opcode_t *)__kretprobe_trampoline) > return 1; > > return 0; > } > +NOKPROBE_SYMBOL(arch_trampoline_kprobe); > > static struct kprobe trampoline_p = { > .addr = (kprobe_opcode_t *)__kretprobe_trampoline, > diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c > index 44f9810..b08bc55 100644 > --- a/arch/mips/mm/fault.c > +++ b/arch/mips/mm/fault.c > @@ -35,7 +35,7 @@ int show_unhandled_signals = 1; > * and the problem, and then passes it off to one of the appropriate > * routines. > */ > -static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, > +static void __do_page_fault(struct pt_regs *regs, unsigned long write, > unsigned long address) > { > struct vm_area_struct * vma = NULL; > @@ -322,8 +322,9 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, > } > #endif > } > +NOKPROBE_SYMBOL(__do_page_fault); > > -asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, > +asmlinkage void do_page_fault(struct pt_regs *regs, > unsigned long write, unsigned long address) > { > enum ctx_state prev_state; > @@ -332,3 +333,4 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, > __do_page_fault(regs, write, address); > exception_exit(prev_state); > } > +NOKPROBE_SYMBOL(do_page_fault); > -- > 2.1.0 > -- Masami Hiramatsu Next message: Rex-BC Chen: "Re: [PATCH v6 05/10] cpufreq: mediatek: Add opp notification support" Previous message: Peng Liu: "[PATCH 2/2] null_blk: fix wrong use of nr_online_nodes" In reply to: Tiezhu Yang: "[PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation" Next in thread: Tiezhu Yang: "Re: [PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation" Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
