parisc/ftrace: Add KPROBES_ON_FTRACE

Allow KPROBES to use the ftrace infrastructure on PA-RISC.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt b/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt
index 68f266944d5fce3aecd8a85e7e3f5717bdfba778..4fae0464ddff27807da70c2fcc664fa2ba8f8680 100644 (file)
--- a/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt
+++ b/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt
@@ -21,7 +21,7 @@
     |       nds32: | TODO |
     |       nios2: | TODO |
     |    openrisc: | TODO |
-    |      parisc: | TODO |
+    |      parisc: |  ok  |
     |     powerpc: |  ok  |
     |       riscv: | TODO |
     |        s390: | TODO |

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 6d732e4510713391989914fa244f2798d37052be..ee59171edffe358781e1f8dd60135f4b85d1e86f 100644 (file)
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -61,6 +61,8 @@ config PARISC
        select HAVE_KRETPROBES
        select HAVE_DYNAMIC_FTRACE if $(cc-option,-fpatchable-function-entry=1,1)
        select HAVE_FTRACE_MCOUNT_RECORD if HAVE_DYNAMIC_FTRACE
+       select HAVE_KPROBES_ON_FTRACE
+       select HAVE_DYNAMIC_FTRACE_WITH_REGS
 
        help
          The PA-RISC microprocessor is designed by Hewlett-Packard and used

diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S
index d9d3387f7c478bc6f53f12c0fa34384fefabe0c9..1d1d748c227f075685f79dc327bfc52a029885d1 100644 (file)
--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -1996,6 +1996,7 @@ _mcount:
         * calling mcount(), and 2 instructions for ftrace_stub().  That way we
         * have all on one L1 cacheline.
         */
+       ldi     0, %arg3
        b       ftrace_function_trampoline
        copy    %r3, %arg2      /* caller original %sp */
 ftrace_stub:
@@ -2048,6 +2049,7 @@ ftrace_caller:
        LDREG   0(%r3), %r25
        copy    %rp, %r26
        ldo     -8(%r25), %r25
+       ldi     0, %r23         /* no pt_regs */
        b,l     ftrace_function_trampoline, %rp
        copy    %r3, %r24
 
@@ -2075,6 +2077,103 @@ ftrace_caller:
 
 ENDPROC_CFI(ftrace_caller)
 
+#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS
+ENTRY_CFI(ftrace_regs_caller,caller,frame=FTRACE_FRAME_SIZE+PT_SZ_ALGN,
+       CALLS,SAVE_RP,SAVE_SP)
+ftrace_regs_caller:
+       .global ftrace_regs_caller
+
+       ldo     -FTRACE_FRAME_SIZE(%sp), %r1
+       STREG   %rp, -RP_OFFSET(%r1)
+
+       copy    %sp, %r1
+       ldo     PT_SZ_ALGN(%sp), %sp
+
+       STREG   %rp, PT_GR2(%r1)
+       STREG   %r3, PT_GR3(%r1)
+       STREG   %r4, PT_GR4(%r1)
+       STREG   %r5, PT_GR5(%r1)
+       STREG   %r6, PT_GR6(%r1)
+       STREG   %r7, PT_GR7(%r1)
+       STREG   %r8, PT_GR8(%r1)
+       STREG   %r9, PT_GR9(%r1)
+       STREG   %r10, PT_GR10(%r1)
+       STREG   %r11, PT_GR11(%r1)
+       STREG   %r12, PT_GR12(%r1)
+       STREG   %r13, PT_GR13(%r1)
+       STREG   %r14, PT_GR14(%r1)
+       STREG   %r15, PT_GR15(%r1)
+       STREG   %r16, PT_GR16(%r1)
+       STREG   %r17, PT_GR17(%r1)
+       STREG   %r18, PT_GR18(%r1)
+       STREG   %r19, PT_GR19(%r1)
+       STREG   %r20, PT_GR20(%r1)
+       STREG   %r21, PT_GR21(%r1)
+       STREG   %r22, PT_GR22(%r1)
+       STREG   %r23, PT_GR23(%r1)
+       STREG   %r24, PT_GR24(%r1)
+       STREG   %r25, PT_GR25(%r1)
+       STREG   %r26, PT_GR26(%r1)
+       STREG   %r27, PT_GR27(%r1)
+       STREG   %r28, PT_GR28(%r1)
+       STREG   %r29, PT_GR29(%r1)
+       STREG   %r30, PT_GR30(%r1)
+       STREG   %r31, PT_GR31(%r1)
+       mfctl   %cr11, %r26
+       STREG   %r26, PT_SAR(%r1)
+
+       copy    %rp, %r26
+       LDREG   -FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25
+       ldo     -8(%r25), %r25
+       copy    %r3, %arg2
+       b,l     ftrace_function_trampoline, %rp
+       copy    %r1, %arg3 /* struct pt_regs */
+
+       ldo     -PT_SZ_ALGN(%sp), %r1
+
+       LDREG   PT_SAR(%r1), %rp
+       mtctl   %rp, %cr11
+
+       LDREG   PT_GR2(%r1), %rp
+       LDREG   PT_GR3(%r1), %r3
+       LDREG   PT_GR4(%r1), %r4
+       LDREG   PT_GR5(%r1), %r5
+       LDREG   PT_GR6(%r1), %r6
+       LDREG   PT_GR7(%r1), %r7
+       LDREG   PT_GR8(%r1), %r8
+       LDREG   PT_GR9(%r1), %r9
+       LDREG   PT_GR10(%r1),%r10
+       LDREG   PT_GR11(%r1),%r11
+       LDREG   PT_GR12(%r1),%r12
+       LDREG   PT_GR13(%r1),%r13
+       LDREG   PT_GR14(%r1),%r14
+       LDREG   PT_GR15(%r1),%r15
+       LDREG   PT_GR16(%r1),%r16
+       LDREG   PT_GR17(%r1),%r17
+       LDREG   PT_GR18(%r1),%r18
+       LDREG   PT_GR19(%r1),%r19
+       LDREG   PT_GR20(%r1),%r20
+       LDREG   PT_GR21(%r1),%r21
+       LDREG   PT_GR22(%r1),%r22
+       LDREG   PT_GR23(%r1),%r23
+       LDREG   PT_GR24(%r1),%r24
+       LDREG   PT_GR25(%r1),%r25
+       LDREG   PT_GR26(%r1),%r26
+       LDREG   PT_GR27(%r1),%r27
+       LDREG   PT_GR28(%r1),%r28
+       LDREG   PT_GR29(%r1),%r29
+       LDREG   PT_GR30(%r1),%r30
+       LDREG   PT_GR31(%r1),%r31
+
+       ldo     -PT_SZ_ALGN(%sp), %sp
+       LDREGM  -FTRACE_FRAME_SIZE(%sp), %r1
+       /* Adjust return point to jump back to beginning of traced function */
+       ldo     -4(%r1), %r1
+       bv,n    (%r1)
+
+ENDPROC_CFI(ftrace_regs_caller)
+
+#endif
 #endif
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER

diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c
index 23ce416787ac33709056cc82cce3583d99717483..b836fc61a24f4b7cd1cdb7975fddc4962cef8a97 100644 (file)
--- a/arch/parisc/kernel/ftrace.c
+++ b/arch/parisc/kernel/ftrace.c
@@ -13,6 +13,8 @@
 #include <linux/init.h>
 #include <linux/ftrace.h>
 #include <linux/uaccess.h>
+#include <linux/kprobes.h>
+#include <linux/ptrace.h>
 
 #include <asm/assembly.h>
 #include <asm/sections.h>
@@ -48,7 +50,8 @@ static void __hot prepare_ftrace_return(unsigned long *parent,
 
 void notrace __hot ftrace_function_trampoline(unsigned long parent,
                                unsigned long self_addr,
-                               unsigned long org_sp_gr3)
+                               unsigned long org_sp_gr3,
+                               struct pt_regs *regs)
 {
 #ifndef CONFIG_DYNAMIC_FTRACE
        extern ftrace_func_t ftrace_trace_function;
@@ -58,11 +61,11 @@ void notrace __hot ftrace_function_trampoline(unsigned long parent,
        if (function_trace_op->flags & FTRACE_OPS_FL_ENABLED &&
            ftrace_trace_function != ftrace_stub)
                ftrace_trace_function(self_addr, parent,
-                               function_trace_op, NULL);
+                               function_trace_op, regs);
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
        if (ftrace_graph_return != (trace_func_graph_ret_t) ftrace_stub ||
-               ftrace_graph_entry != ftrace_graph_entry_stub) {
+           ftrace_graph_entry != ftrace_graph_entry_stub) {
                unsigned long *parent_rp;
 
                /* calculate pointer to %rp in stack */
@@ -100,6 +103,12 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
        return 0;
 }
 
+int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
+                       unsigned long addr)
+{
+       return 0;
+}
+
 unsigned long ftrace_call_adjust(unsigned long addr)
 {
        return addr+(FTRACE_PATCHABLE_FUNCTION_SIZE-1)*4;
@@ -191,3 +200,46 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
        return 0;
 }
 #endif
+
+#ifdef CONFIG_KPROBES_ON_FTRACE
+void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
+                          struct ftrace_ops *ops, struct pt_regs *regs)
+{
+       struct kprobe_ctlblk *kcb;
+       struct kprobe *p = get_kprobe((kprobe_opcode_t *)ip);
+
+       if (unlikely(!p) || kprobe_disabled(p))
+               return;
+
+       if (kprobe_running()) {
+               kprobes_inc_nmissed_count(p);
+               return;
+       }
+
+       __this_cpu_write(current_kprobe, p);
+
+       kcb = get_kprobe_ctlblk();
+       kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+
+       regs->iaoq[0] = ip;
+       regs->iaoq[1] = ip + 4;
+
+       if (!p->pre_handler || !p->pre_handler(p, regs)) {
+               regs->iaoq[0] = ip + 4;
+               regs->iaoq[1] = ip + 8;
+
+               if (unlikely(p->post_handler)) {
+                       kcb->kprobe_status = KPROBE_HIT_SSDONE;
+                       p->post_handler(p, regs, 0);
+               }
+       }
+       __this_cpu_write(current_kprobe, NULL);
+}
+NOKPROBE_SYMBOL(kprobe_ftrace_handler);
+
+int arch_prepare_kprobe_ftrace(struct kprobe *p)
+{
+       p->ainsn.insn = NULL;
+       return 0;
+}
+#endif