Commit 84d5f77f authored by H.J. Lu's avatar H.J. Lu Committed by Borislav Petkov

x86, vmlinux.lds: Add RUNTIME_DISCARD_EXIT to generic DISCARDS

In the x86 kernel, .exit.text and .exit.data sections are discarded at
runtime, not by the linker. Add RUNTIME_DISCARD_EXIT to generic DISCARDS
and define it in the x86 kernel linker script to keep them.

The sections are added before the DISCARD directive so document here
only the situation explicitly as this change doesn't have any effect on
the generated kernel. Also, other architectures like ARM64 will use it
too so generalize the approach with the RUNTIME_DISCARD_EXIT define.

 [ bp: Massage and extend commit message. ]
Signed-off-by: default avatarH.J. Lu <hjl.tools@gmail.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200326193021.255002-1-hjl.tools@gmail.com
parent 645e6466
......@@ -21,6 +21,7 @@
#define LOAD_OFFSET __START_KERNEL_map
#endif
#define RUNTIME_DISCARD_EXIT
#define EMITS_PT_NOTE
#define RO_EXCEPTION_TABLE_ALIGN 16
......
......@@ -894,10 +894,17 @@
* section definitions so that such archs put those in earlier section
* definitions.
*/
#ifdef RUNTIME_DISCARD_EXIT
#define EXIT_DISCARDS
#else
#define EXIT_DISCARDS \
EXIT_TEXT \
EXIT_DATA
#endif
#define DISCARDS \
/DISCARD/ : { \
EXIT_TEXT \
EXIT_DATA \
EXIT_DISCARDS \
EXIT_CALL \
*(.discard) \
*(.discard.*) \
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment