[Crash-utility] [RFC] arm64: symbolize PLT entries in disassembling module functions
Signed-off-by: AKASHI Takahiro <takahiro.akashi(a)linaro.org>
---
arm64.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 69 insertions(+)
diff --git a/arm64.c b/arm64.c
index b9fa14d..8235e3c 100644
--- a/arm64.c
+++ b/arm64.c
@@ -2540,6 +2540,59 @@ arm64_is_task_addr(ulong task)
return (IS_KVADDR(task) && (ALIGNED_STACK_OFFSET(task) == 0));
}
+static ulong
+PLT_veneer_to_kvaddr(ulong value)
+{
+ uint32_t insn;
+ ulong addr = 0;
+ int i;
+
+ /*
+ * PLT veneer always looks:
+ * movn x16, #0x....
+ * movk x16, #0x...., lsl #16
+ * movk x16, #0x...., lsl #32
+ * br x16
+ */
+ for (i = 0; i < 4; i++) {
+ if (!readmem(value + i * sizeof(insn), KVADDR, &insn,
+ sizeof(insn), "PLT veneer", RETURN_ON_ERROR)) {
+ error(WARNING, "cannot read PLT veneer\n");
+ return value;
+ }
+ switch (i) {
+ case 0:
+ if ((insn & 0xffe0001f) != 0x92800010)
+ goto not_plt;
+ addr = ~((ulong)(insn & 0x1fffe0) >> 5);
+ break;
+ case 1:
+ if ((insn & 0xffe0001f) != 0xf2a00010)
+ goto not_plt;
+ addr &= 0xffffffff0000ffff;
+ addr |= (ulong)(insn & 0x1fffe0) << (16 - 5);
+ break;
+ case 2:
+ if ((insn & 0xffe0001f) != 0xf2c00010)
+ goto not_plt;
+ addr &= 0xffff0000ffffffff;
+ addr |= (ulong)(insn & 0x1fffe0) << (32 - 5);
+ break;
+ case 3:
+ if (insn != 0xd61f0200)
+ goto not_plt;
+ break;
+ default:
+ return value; /* to avoid any warnings */
+ }
+ }
+
+ return addr;
+
+not_plt:
+ return value;
+}
+
/*
* Filter dissassembly output if the output radix is not gdb's default 10
*/
@@ -2589,6 +2642,22 @@ arm64_dis_filter(ulong vaddr, char *inbuf, unsigned int
output_radix)
sprintf(p1, "%s", buf1);
}
+ if (IS_MODULE_VADDR(vaddr)) {
+ ulong orig_value;
+
+ p1 = &inbuf[strlen(inbuf)-1];
+ strcpy(buf1, inbuf);
+ argc = parse_line(buf1, argv);
+
+ if ((STREQ(argv[argc-2], "b") || STREQ(argv[argc-2], "bl"))
&&
+ extract_hex(argv[argc-1], &orig_value, NULLCHAR, TRUE)) {
+ value = PLT_veneer_to_kvaddr(orig_value);
+ sprintf(p1, " <%s%s>\n",
+ value == orig_value ? "" : "plt:",
+ value_to_symstr(value, buf2, output_radix));
+ }
+ }
+
console(" %s", inbuf);
return TRUE;
--
2.10.0