From: Masami Hiramatsu Date: Tue, 19 Jun 2018 16:08:01 +0000 (+0900) Subject: ia64/kprobes: Remove jprobe implementation X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=0aeaf6b3a34588050a32d88177e18a1909bbb994;p=openwrt%2Fstaging%2Fblogic.git ia64/kprobes: Remove jprobe implementation Remove arch dependent setjump/longjump functions and unused fields in kprobe_ctlblk for jprobes from arch/ia64. Note that since ia64 jprobes code is a bit different from other architectures, this keeps __IA64_BREAK_JPROBE for checking the ->break_handler(). It will be removed with the break_handler() calls afterwards. Signed-off-by: Masami Hiramatsu Acked-by: Thomas Gleixner Cc: Ananth N Mavinakayanahalli Cc: Andrew Morton Cc: Fenghua Yu Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Tony Luck Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Link: https://lore.kernel.org/lkml/152942448152.15209.2026051332977587306.stgit@devbox Signed-off-by: Ingo Molnar --- diff --git a/arch/ia64/include/asm/kprobes.h b/arch/ia64/include/asm/kprobes.h index 0302b3664789..580356a2eea6 100644 --- a/arch/ia64/include/asm/kprobes.h +++ b/arch/ia64/include/asm/kprobes.h @@ -82,8 +82,6 @@ struct prev_kprobe { #define ARCH_PREV_KPROBE_SZ 2 struct kprobe_ctlblk { unsigned long kprobe_status; - struct pt_regs jprobe_saved_regs; - unsigned long jprobes_saved_stacked_regs[MAX_PARAM_RSE_SIZE]; unsigned long *bsp; unsigned long cfm; atomic_t prev_kprobe_index; diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile index 498f3da3f225..d0c0ccdd656a 100644 --- a/arch/ia64/kernel/Makefile +++ b/arch/ia64/kernel/Makefile @@ -25,7 +25,7 @@ obj-$(CONFIG_NUMA) += numa.o obj-$(CONFIG_PERFMON) += perfmon_default_smpl.o obj-$(CONFIG_IA64_CYCLONE) += cyclone.o obj-$(CONFIG_IA64_MCA_RECOVERY) += mca_recovery.o -obj-$(CONFIG_KPROBES) += kprobes.o jprobes.o +obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o obj-$(CONFIG_CRASH_DUMP) += crash_dump.o diff --git a/arch/ia64/kernel/jprobes.S b/arch/ia64/kernel/jprobes.S deleted file mode 100644 index f69389c7be1d..000000000000 --- a/arch/ia64/kernel/jprobes.S +++ /dev/null @@ -1,90 +0,0 @@ -/* - * Jprobe specific operations - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * - * Copyright (C) Intel Corporation, 2005 - * - * 2005-May Rusty Lynch and Anil S Keshavamurthy - * initial implementation - * - * Jprobes (a.k.a. "jump probes" which is built on-top of kprobes) allow a - * probe to be inserted into the beginning of a function call. The fundamental - * difference between a jprobe and a kprobe is the jprobe handler is executed - * in the same context as the target function, while the kprobe handlers - * are executed in interrupt context. - * - * For jprobes we initially gain control by placing a break point in the - * first instruction of the targeted function. When we catch that specific - * break, we: - * * set the return address to our jprobe_inst_return() function - * * jump to the jprobe handler function - * - * Since we fixed up the return address, the jprobe handler will return to our - * jprobe_inst_return() function, giving us control again. At this point we - * are back in the parents frame marker, so we do yet another call to our - * jprobe_break() function to fix up the frame marker as it would normally - * exist in the target function. - * - * Our jprobe_return function then transfers control back to kprobes.c by - * executing a break instruction using one of our reserved numbers. When we - * catch that break in kprobes.c, we continue like we do for a normal kprobe - * by single stepping the emulated instruction, and then returning execution - * to the correct location. - */ -#include -#include - - /* - * void jprobe_break(void) - */ - .section .kprobes.text, "ax" -ENTRY(jprobe_break) - break.m __IA64_BREAK_JPROBE -END(jprobe_break) - - /* - * void jprobe_inst_return(void) - */ -GLOBAL_ENTRY(jprobe_inst_return) - br.call.sptk.many b0=jprobe_break -END(jprobe_inst_return) - -GLOBAL_ENTRY(invalidate_stacked_regs) - movl r16=invalidate_restore_cfm - ;; - mov b6=r16 - ;; - br.ret.sptk.many b6 - ;; -invalidate_restore_cfm: - mov r16=ar.rsc - ;; - mov ar.rsc=r0 - ;; - loadrs - ;; - mov ar.rsc=r16 - ;; - br.cond.sptk.many rp -END(invalidate_stacked_regs) - -GLOBAL_ENTRY(flush_register_stack) - // flush dirty regs to backing store (must be first in insn group) - flushrs - ;; - br.ret.sptk.many rp -END(flush_register_stack) - diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index f5f3a5e6fcd1..823e4bd03a18 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -35,8 +35,6 @@ #include #include -extern void jprobe_inst_return(void); - DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL; DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); @@ -1040,74 +1038,6 @@ unsigned long arch_deref_entry_point(void *entry) return ((struct fnptr *)entry)->ip; } -int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct jprobe *jp = container_of(p, struct jprobe, kp); - unsigned long addr = arch_deref_entry_point(jp->entry); - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - struct param_bsp_cfm pa; - int bytes; - - /* - * Callee owns the argument space and could overwrite it, eg - * tail call optimization. So to be absolutely safe - * we save the argument space before transferring the control - * to instrumented jprobe function which runs in - * the process context - */ - pa.ip = regs->cr_iip; - unw_init_running(ia64_get_bsp_cfm, &pa); - bytes = (char *)ia64_rse_skip_regs(pa.bsp, pa.cfm & 0x3f) - - (char *)pa.bsp; - memcpy( kcb->jprobes_saved_stacked_regs, - pa.bsp, - bytes ); - kcb->bsp = pa.bsp; - kcb->cfm = pa.cfm; - - /* save architectural state */ - kcb->jprobe_saved_regs = *regs; - - /* after rfi, execute the jprobe instrumented function */ - regs->cr_iip = addr & ~0xFULL; - ia64_psr(regs)->ri = addr & 0xf; - regs->r1 = ((struct fnptr *)(jp->entry))->gp; - - /* - * fix the return address to our jprobe_inst_return() function - * in the jprobes.S file - */ - regs->b0 = ((struct fnptr *)(jprobe_inst_return))->ip; - - return 1; -} - -/* ia64 does not need this */ -void __kprobes jprobe_return(void) -{ -} - -int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - int bytes; - - /* restoring architectural state */ - *regs = kcb->jprobe_saved_regs; - - /* restoring the original argument space */ - flush_register_stack(); - bytes = (char *)ia64_rse_skip_regs(kcb->bsp, kcb->cfm & 0x3f) - - (char *)kcb->bsp; - memcpy( kcb->bsp, - kcb->jprobes_saved_stacked_regs, - bytes ); - invalidate_stacked_regs(); - - preempt_enable_no_resched(); - return 1; -} - static struct kprobe trampoline_p = { .pre_handler = trampoline_probe_handler };