linux-kernel - [PATCH] x86-64: Force linker to use 2MB page size

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Date:   Mon, 19 Mar 2018 13:57:46 -0700
From:   "H.J. Lu" <hjl.tools@...il.com>
To:     LKML <linux-kernel@...r.kernel.org>,
        "the arch/x86 maintainers" <x86@...nel.org>
Subject: [PATCH] x86-64: Force linker to use 2MB page size

Binutils 2.31 will enable -z separate-code by default for x86 to avoid
mixing code pages with data to improve cache performance as well as
security.  To reduce x86-64 executable and shared object sizes, the
maximum page size is reduced from 2MB to 4KB.  But x86-64 kernel must
be aligned to 2MB.  Pass -z max-page-size=0x200000 to linker to force
2MB page size regardless of the default page size used by linker.

Tested with Linux kernel 4.15.6 on x86-64.

Signed-off-by: H.J. Lu <hjl.tools@...il.com>

-- 
H.J.

View attachment "0001-x86-64-Force-linker-to-use-2MB-page-size.patch" of type "text/x-patch" (1510 bytes)