From: Yuxuan Shui yshui@codeweavers.com
If wine dlls are built with frame pointers enabled, the frame pointer will be used during unwinding.
If we don't restore frame pointer before calling the user mode callback, then later when the unwinder encounters the user mode callback frame, it will set the frame pointer to something unexpected (depends on what it was during `call_user_mode_callback`). Then for the subsequent frame it adjusts the stack pointer based on the frame pointer, thus derailing the unwinding process. --- dlls/ntdll/unix/signal_x86_64.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/dlls/ntdll/unix/signal_x86_64.c b/dlls/ntdll/unix/signal_x86_64.c index 6ec662b9850..624ca111c43 100644 --- a/dlls/ntdll/unix/signal_x86_64.c +++ b/dlls/ntdll/unix/signal_x86_64.c @@ -1646,6 +1646,7 @@ __ASM_GLOBAL_FUNC( call_user_mode_callback, "movq %r10,0xa0(%rsp)\n\t" /* frame->prev_frame */ "movq %rsp,0x378(%r13)\n\t" /* thread_data->syscall_frame */ "testl $1,0x380(%r13)\n\t" /* thread_data->syscall_trace */ + "movq %r10,%r14\n\t" /* user_frame (previous thread_data->syscall_frame) */ "jz 1f\n\t" "movq %rdi,%r12\n\t" /* user_rsp */ "movl 0x2c(%r12),%edi\n\t" /* id */ @@ -1658,6 +1659,7 @@ __ASM_GLOBAL_FUNC( call_user_mode_callback, "movq %r15,%rcx\n" /* func */ /* switch to user stack */ "1:\tmovq %rdi,%rsp\n\t" /* user_rsp */ + "movq 0x98(%r14),%rbp\n\t" /* user_frame->Rbp */ #ifdef __linux__ "movw 0x338(%r13),%ax\n" /* amd64_thread_data()->fs */ "testw %ax,%ax\n\t"