Revert "arm64: rethook: Add arm64 rethook implementation"

This reverts commit fc09afbf58c59c81bab4bdb95d4b13cb209e94c9.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 62cff9d0a5bbbef88fdee1f70a7fca815e3e3e81..09b885cc4db531fd18debbb2d3cd43e5aa5cdd58 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -201,7 +201,6 @@ config ARM64
        select HAVE_SYSCALL_TRACEPOINTS
        select HAVE_KPROBES
        select HAVE_KRETPROBES
-       select HAVE_RETHOOK
        select HAVE_GENERIC_VDSO
        select IOMMU_DMA if IOMMU_SUPPORT
        select IRQ_DOMAIN

diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h
index bf04107da97c7ceb5a89daa1ac2b088e58e3611e..e77cdef9ca29bba1ca37954c6880d2a48354d9cf 100644 (file)
--- a/arch/arm64/include/asm/stacktrace.h
+++ b/arch/arm64/include/asm/stacktrace.h
@@ -58,7 +58,7 @@ struct stackframe {
        DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES);
        unsigned long prev_fp;
        enum stack_type prev_type;
-#if defined(CONFIG_KRETPROBES) || defined(CONFIG_RETHOOK)
+#ifdef CONFIG_KRETPROBES
        struct llist_node *kr_cur;
 #endif
 };

diff --git a/arch/arm64/kernel/probes/Makefile b/arch/arm64/kernel/probes/Makefile
index 24e689f44c32df5db5d802614c040fe894023dd2..8e4be92e25b17017176b7f4e8a68acb95e934308 100644 (file)
--- a/arch/arm64/kernel/probes/Makefile
+++ b/arch/arm64/kernel/probes/Makefile
@@ -4,4 +4,3 @@ obj-$(CONFIG_KPROBES)           += kprobes.o decode-insn.o      \
                                   simulate-insn.o
 obj-$(CONFIG_UPROBES)          += uprobes.o decode-insn.o      \
                                   simulate-insn.o
-obj-$(CONFIG_RETHOOK)          += rethook.o rethook_trampoline.o

diff --git a/arch/arm64/kernel/probes/rethook.c b/arch/arm64/kernel/probes/rethook.c
deleted file mode 100644 (file)
index edc6b80..0000000
--- a/arch/arm64/kernel/probes/rethook.c
+++ /dev/null
@@ -1,25 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Generic return hook for arm64.
- * Most of the code is copied from arch/arm64/kernel/probes/kprobes.c
- */
-
-#include <linux/kprobes.h>
-#include <linux/rethook.h>
-
-/* This is called from arch_rethook_trampoline() */
-unsigned long __used arch_rethook_trampoline_callback(struct pt_regs *regs)
-{
-       return rethook_trampoline_handler(regs, regs->regs[29]);
-}
-NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);
-
-void arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs *regs, bool mcount)
-{
-       rhn->ret_addr = regs->regs[30];
-       rhn->frame = regs->regs[29];
-
-       /* replace return addr (x30) with trampoline */
-       regs->regs[30] = (u64)arch_rethook_trampoline;
-}
-NOKPROBE_SYMBOL(arch_rethook_prepare);

diff --git a/arch/arm64/kernel/probes/rethook_trampoline.S b/arch/arm64/kernel/probes/rethook_trampoline.S
deleted file mode 100644 (file)
index 610f520..0000000
--- a/arch/arm64/kernel/probes/rethook_trampoline.S
+++ /dev/null
@@ -1,87 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * trampoline entry and return code for rethook.
- * Copied from arch/arm64/kernel/probes/kprobes_trampoline.S
- */
-
-#include <linux/linkage.h>
-#include <asm/asm-offsets.h>
-#include <asm/assembler.h>
-
-       .text
-
-       .macro  save_all_base_regs
-       stp x0, x1, [sp, #S_X0]
-       stp x2, x3, [sp, #S_X2]
-       stp x4, x5, [sp, #S_X4]
-       stp x6, x7, [sp, #S_X6]
-       stp x8, x9, [sp, #S_X8]
-       stp x10, x11, [sp, #S_X10]
-       stp x12, x13, [sp, #S_X12]
-       stp x14, x15, [sp, #S_X14]
-       stp x16, x17, [sp, #S_X16]
-       stp x18, x19, [sp, #S_X18]
-       stp x20, x21, [sp, #S_X20]
-       stp x22, x23, [sp, #S_X22]
-       stp x24, x25, [sp, #S_X24]
-       stp x26, x27, [sp, #S_X26]
-       stp x28, x29, [sp, #S_X28]
-       add x0, sp, #PT_REGS_SIZE
-       stp lr, x0, [sp, #S_LR]
-       /*
-        * Construct a useful saved PSTATE
-        */
-       mrs x0, nzcv
-       mrs x1, daif
-       orr x0, x0, x1
-       mrs x1, CurrentEL
-       orr x0, x0, x1
-       mrs x1, SPSel
-       orr x0, x0, x1
-       stp xzr, x0, [sp, #S_PC]
-       .endm
-
-       .macro  restore_all_base_regs
-       ldr x0, [sp, #S_PSTATE]
-       and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT)
-       msr nzcv, x0
-       ldp x0, x1, [sp, #S_X0]
-       ldp x2, x3, [sp, #S_X2]
-       ldp x4, x5, [sp, #S_X4]
-       ldp x6, x7, [sp, #S_X6]
-       ldp x8, x9, [sp, #S_X8]
-       ldp x10, x11, [sp, #S_X10]
-       ldp x12, x13, [sp, #S_X12]
-       ldp x14, x15, [sp, #S_X14]
-       ldp x16, x17, [sp, #S_X16]
-       ldp x18, x19, [sp, #S_X18]
-       ldp x20, x21, [sp, #S_X20]
-       ldp x22, x23, [sp, #S_X22]
-       ldp x24, x25, [sp, #S_X24]
-       ldp x26, x27, [sp, #S_X26]
-       ldp x28, x29, [sp, #S_X28]
-       .endm
-
-SYM_CODE_START(arch_rethook_trampoline)
-       sub sp, sp, #PT_REGS_SIZE
-
-       save_all_base_regs
-
-       /* Setup a frame pointer. */
-       add x29, sp, #S_FP
-
-       mov x0, sp
-       bl arch_rethook_trampoline_callback
-       /*
-        * Replace trampoline address in lr with actual orig_ret_addr return
-        * address.
-        */
-       mov lr, x0
-
-       /* The frame pointer (x29) is restored with other registers. */
-       restore_all_base_regs
-
-       add sp, sp, #PT_REGS_SIZE
-       ret
-
-SYM_CODE_END(arch_rethook_trampoline)

diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index efb5b85b57c26ae58e9122808bf5b71ab7580b3a..e4103e085681143e5f285c91d428f152d7013a6d 100644 (file)
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -8,7 +8,6 @@
 #include <linux/export.h>
 #include <linux/ftrace.h>
 #include <linux/kprobes.h>
-#include <linux/rethook.h>
 #include <linux/sched.h>
 #include <linux/sched/debug.h>
 #include <linux/sched/task_stack.h>
@@ -39,7 +38,7 @@ static notrace void start_backtrace(struct stackframe *frame, unsigned long fp,
 {
        frame->fp = fp;
        frame->pc = pc;
-#if defined(CONFIG_KRETPROBES) || defined(CONFIG_RETHOOK)
+#ifdef CONFIG_KRETPROBES
        frame->kr_cur = NULL;
 #endif
 
@@ -139,10 +138,6 @@ static int notrace unwind_frame(struct task_struct *tsk,
        if (is_kretprobe_trampoline(frame->pc))
                frame->pc = kretprobe_find_ret_addr(tsk, (void *)frame->fp, &frame->kr_cur);
 #endif
-#ifdef CONFIG_RETHOOK
-       if (is_rethook_trampoline(frame->pc))
-               frame->pc = rethook_find_ret_addr(tsk, frame->fp, &frame->kr_cur);
-#endif
 
        return 0;
 }