s390: discard .interp section

commit e9c9cb90e76ffaabcc7ca8f275d9e82195fd6367 upstream.

When debugging vmlinux with QEMU + GDB, the following GDB error may
occur:

    (gdb) c
    Continuing.
    Warning:
    Cannot insert breakpoint -1.
    Cannot access memory at address 0xffffffffffff95c0

    Command aborted.
    (gdb)

The reason is that, when .interp section is present, GDB tries to
locate the file specified in it in memory and put a number of
breakpoints there (see enable_break() function in gdb/solib-svr4.c).
Sometimes GDB finds a bogus location that matches its heuristics,
fails to set a breakpoint and stops. This makes further debugging
impossible.

The .interp section contains misleading information anyway (vmlinux
does not need ld.so), so fix by discarding it.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 4df41695caec8a7382258f4197be46a23b70956b..99053c80388e438fbcb1b695c8a56f69548d3848 100644 (file)
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -189,5 +189,6 @@ SECTIONS
        DISCARDS
        /DISCARD/ : {
                *(.eh_frame)
+               *(.interp)
        }
 }