]> www.infradead.org Git - users/jedix/linux-maple.git/commit
x86/xen: don't write ptes directly in 32-bit PV guests
authorJuergen Gross <jgross@suse.com>
Tue, 21 Aug 2018 15:37:54 +0000 (17:37 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 15 Sep 2018 07:45:35 +0000 (09:45 +0200)
commit13b23ccfa28811333b866196e38d0bc35f68240d
treeb407bd63a6729dff31608929f0ff511f74eebd57
parentd85c2999a7b5e924172f0cc21f5804bbb1f34d69
x86/xen: don't write ptes directly in 32-bit PV guests

commit f7c90c2aa4004808dff777ba6ae2c7294dd06851 upstream.

In some cases 32-bit PAE PV guests still write PTEs directly instead of
using hypercalls. This is especially bad when clearing a PTE as this is
done via 32-bit writes which will produce intermediate L1TF attackable
PTEs.

Change the code to use hypercalls instead.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/xen/mmu_pv.c