aarch64: fix stack missing after sp is updated

Message ID 20210105015920.31812-1-wangshuo47@huawei.com
State Committed
Commit cd6274089f7a7603cdaf2a24cef575fa61d3772e
Headers
Series aarch64: fix stack missing after sp is updated |

Commit Message

Shuo Wang Jan. 5, 2021, 1:59 a.m. UTC
  After sp is updated, the CFA offset should be set before next instruction.
Tested in glibc-2.28:
Thread 2 "xxxxxxx" hit Breakpoint 1, _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
149		stp	x1,  x2, [sp, #-32]!
Missing separate debuginfos, use: dnf debuginfo-install libgcc-7.3.0-20190804.h24.aarch64
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:149
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
150		stp	x3,  x4, [sp, #16]
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:150
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) ni
_dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
157		mrs	x4, tpidr_el0
(gdb) bt
#0  _dl_tlsdesc_dynamic () at ../sysdeps/aarch64/dl-tlsdesc.S:157
#1  0x0000ffffbe4fbb44 in OurFunction (threadId=3194870184)
    at /home/test/test_function.c:30
#2  0x0000000000400c08 in initaaa () at thread.c:58
#3  0x0000000000400c50 in thread_proc (param=0x0) at thread.c:71
#4  0x0000ffffbf6918bc in start_thread (arg=0xfffffffff29f) at pthread_create.c:486
#5  0x0000ffffbf5669ec in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78

Co-authored-by: liqingqing <liqingqing3@huawei.com>
---
 sysdeps/aarch64/dl-tlsdesc.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Patch

diff --git a/sysdeps/aarch64/dl-tlsdesc.S b/sysdeps/aarch64/dl-tlsdesc.S
index 0046d29f9b..425e45a50f 100644
--- a/sysdeps/aarch64/dl-tlsdesc.S
+++ b/sysdeps/aarch64/dl-tlsdesc.S
@@ -150,8 +150,8 @@  _dl_tlsdesc_dynamic:
 	/* Save just enough registers to support fast path, if we fall
 	   into slow path we will save additional registers.  */
 	stp	x1,  x2, [sp, #-32]!
-	stp	x3,  x4, [sp, #16]
 	cfi_adjust_cfa_offset (32)
+	stp	x3,  x4, [sp, #16]
 	cfi_rel_offset (x1, 0)
 	cfi_rel_offset (x2, 8)
 	cfi_rel_offset (x3, 16)