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Diffstat (limited to 'arch/s390/kernel/kprobes.c')
-rw-r--r--arch/s390/kernel/kprobes.c59
1 files changed, 39 insertions, 20 deletions
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index fc30e799bd84..aae24dc75df6 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -7,6 +7,7 @@
* s390 port, used ppc64 as template. Mike Grundy <grundym@us.ibm.com>
*/
+#include <linux/moduleloader.h>
#include <linux/kprobes.h>
#include <linux/ptrace.h>
#include <linux/preempt.h>
@@ -21,6 +22,7 @@
#include <asm/set_memory.h>
#include <asm/sections.h>
#include <asm/dis.h>
+#include "entry.h"
DEFINE_PER_CPU(struct kprobe *, current_kprobe);
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -30,19 +32,32 @@ struct kretprobe_blackpoint kretprobe_blacklist[] = { };
DEFINE_INSN_CACHE_OPS(s390_insn);
static int insn_page_in_use;
-static char insn_page[PAGE_SIZE] __aligned(PAGE_SIZE);
+
+void *alloc_insn_page(void)
+{
+ void *page;
+
+ page = module_alloc(PAGE_SIZE);
+ if (!page)
+ return NULL;
+ __set_memory((unsigned long) page, 1, SET_MEMORY_RO | SET_MEMORY_X);
+ return page;
+}
+
+void free_insn_page(void *page)
+{
+ module_memfree(page);
+}
static void *alloc_s390_insn_page(void)
{
if (xchg(&insn_page_in_use, 1) == 1)
return NULL;
- set_memory_x((unsigned long) &insn_page, 1);
- return &insn_page;
+ return &kprobes_insn_page;
}
static void free_s390_insn_page(void *page)
{
- set_memory_nx((unsigned long) page, 1);
xchg(&insn_page_in_use, 0);
}
@@ -56,25 +71,29 @@ struct kprobe_insn_cache kprobe_s390_insn_slots = {
static void copy_instruction(struct kprobe *p)
{
+ kprobe_opcode_t insn[MAX_INSN_SIZE];
s64 disp, new_disp;
u64 addr, new_addr;
+ unsigned int len;
- memcpy(p->ainsn.insn, p->addr, insn_length(*p->addr >> 8));
- p->opcode = p->ainsn.insn[0];
- if (!probe_is_insn_relative_long(p->ainsn.insn))
- return;
- /*
- * For pc-relative instructions in RIL-b or RIL-c format patch the
- * RI2 displacement field. We have already made sure that the insn
- * slot for the patched instruction is within the same 2GB area
- * as the original instruction (either kernel image or module area).
- * Therefore the new displacement will always fit.
- */
- disp = *(s32 *)&p->ainsn.insn[1];
- addr = (u64)(unsigned long)p->addr;
- new_addr = (u64)(unsigned long)p->ainsn.insn;
- new_disp = ((addr + (disp * 2)) - new_addr) / 2;
- *(s32 *)&p->ainsn.insn[1] = new_disp;
+ len = insn_length(*p->addr >> 8);
+ memcpy(&insn, p->addr, len);
+ p->opcode = insn[0];
+ if (probe_is_insn_relative_long(&insn[0])) {
+ /*
+ * For pc-relative instructions in RIL-b or RIL-c format patch
+ * the RI2 displacement field. We have already made sure that
+ * the insn slot for the patched instruction is within the same
+ * 2GB area as the original instruction (either kernel image or
+ * module area). Therefore the new displacement will always fit.
+ */
+ disp = *(s32 *)&insn[1];
+ addr = (u64)(unsigned long)p->addr;
+ new_addr = (u64)(unsigned long)p->ainsn.insn;
+ new_disp = ((addr + (disp * 2)) - new_addr) / 2;
+ *(s32 *)&insn[1] = new_disp;
+ }
+ s390_kernel_write(p->ainsn.insn, &insn, len);
}
NOKPROBE_SYMBOL(copy_instruction);