Allow KPROBES to use the ftrace infrastructure on PA-RISC.
Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxxx>
---
.../debug/kprobes-on-ftrace/arch-support.txt | 2 +-
arch/parisc/Kconfig | 2 +
arch/parisc/kernel/entry.S | 99 +++++++++++++++++++
arch/parisc/kernel/ftrace.c | 58 ++++++++++-
4 files changed, 157 insertions(+), 4 deletions(-)
diff --git a/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt b/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt
index 68f266944d5f..4fae0464ddff 100644
--- 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 6d732e451071..ee59171edffe 100644
--- 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 d9d3387f7c47..1d1d748c227f 100644
--- 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 ea5c50de0b65..2c6086dbfe68 100644
--- 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;
@@ -190,3 +199,46 @@ 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
--
2.20.1
