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 cbf9c1b0beda4a8a82c5821fc97f23410d5ecd31..729d4f949cfe85b03148585c46206a8a1bb0d17b 100644 (file)
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -228,5 +228,6 @@ SECTIONS
        DISCARDS
        /DISCARD/ : {
                *(.eh_frame)
+               *(.interp)
        }
 }