linux-kernel - [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections from bzImage

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Date:   Thu,  9 Jan 2020 10:02:18 -0500
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>
Cc:     x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections from bzImage

Discarding the sections that are unused in the compressed kernel saves
about 10 KiB on 32-bit and 6 KiB on 64-bit, mostly from .eh_frame.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
---
 arch/x86/boot/compressed/vmlinux.lds.S | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S
index 508cfa6828c5..12a20603d92e 100644
--- a/arch/x86/boot/compressed/vmlinux.lds.S
+++ b/arch/x86/boot/compressed/vmlinux.lds.S
@@ -73,4 +73,9 @@ SECTIONS
 #endif
 	. = ALIGN(PAGE_SIZE);	/* keep ZO size page aligned */
 	_end = .;
+
+	/* Discard all remaining sections */
+	/DISCARD/ : {
+		*(*)
+	}
 }
-- 
2.24.1