MIPS: kprobe: Add support.
This patch is based on previous work by Sony and Himanshu Chauhan.
I have done some cleanup and implemented JProbes and KRETPROBES. The
KRETPROBES part is pretty much copied verbatim from powerpc. A possible
future enhance might be to factor out the common code.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Himanshu Chauhan <hschauhan@nulltrace.org>
To: linux-mips@linux-mips.org
To: ananth@in.ibm.com,
To: anil.s.keshavamurthy@intel.com
To: davem@davemloft.net
To: masami.hiramatsu.pt@hitachi.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1525/
Patchwork: https://patchwork.linux-mips.org/patch/1530/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index b4aac42..783ad00 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -17,6 +17,7 @@
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/module.h>
+#include <linux/kprobes.h>
#include <asm/branch.h>
#include <asm/mmu_context.h>
@@ -24,13 +25,14 @@
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/highmem.h> /* For VMALLOC_END */
+#include <linux/kdebug.h>
/*
* This routine handles page faults. It determines the address,
* and the problem, and then passes it off to one of the appropriate
* routines.
*/
-asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
+asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long write,
unsigned long address)
{
struct vm_area_struct * vma = NULL;
@@ -46,6 +48,17 @@
field, regs->cp0_epc);
#endif
+#ifdef CONFIG_KPROBES
+ /*
+ * This is to notify the fault handler of the kprobes. The
+ * exception code is redundant as it is also carried in REGS,
+ * but we pass it anyhow.
+ */
+ if (notify_die(DIE_PAGE_FAULT, "page fault", regs, -1,
+ (regs->cp0_cause >> 2) & 0x1f, SIGSEGV) == NOTIFY_STOP)
+ return;
+#endif
+
info.si_code = SEGV_MAPERR;
/*