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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Jeremy Linton <jeremy.linton@arm.com>,
        Andre Przywara <andre.przywara@arm.com>,
        Jonathan Corbet <corbet@lwn.net>
Subject: [PATCH 4.14 26/46] Documentation: Document arm64 kpti control
Date:   Tue, 28 Jan 2020 14:58:00 +0100
Message-Id: <20200128135753.205297926@linuxfoundation.org>
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From: Jeremy Linton <jeremy.linton@arm.com>

commit de19055564c8f8f9d366f8db3395836da0b2176c upstream.

For a while Arm64 has been capable of force enabling
or disabling the kpti mitigations. Lets make sure the
documentation reflects that.

Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 Documentation/admin-guide/kernel-parameters.txt |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1845,6 +1845,12 @@
 			Built with CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF=y,
 			the default is off.
 
+	kpti=		[ARM64] Control page table isolation of user
+			and kernel address spaces.
+			Default: enabled on cores which need mitigation.
+			0: force disabled
+			1: force enabled
+
 	kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
 			Default is 0 (don't ignore, but inject #GP)