Re: [Xen-devel] [PATCH v7 3/3] x86: Make the GDT remapping read-only on 64-bit

2017-03-14 Thread H. Peter Anvin
,"Luis R . Rodriguez" ,Stanislaw Gruszka ,Peter Zijlstra ,Josh Poimboeuf ,Vitaly Kuznetsov ,Tim Chen ,Joerg Roedel ,=?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= ,the arch/x86 maintainers ,LKML ,linux-...@vger.kernel.org,kasan-dev ,Linux-MM ,Linux PM list ,linux-...@vger.kernel.org,xen-de...@lists.xenpr

Re: [Xen-devel] [PATCH v7 3/3] x86: Make the GDT remapping read-only on 64-bit

2017-03-14 Thread Thomas Garnier
On Tue, Mar 14, 2017 at 2:04 PM, Pavel Machek wrote: > On Tue 2017-03-14 10:05:08, Thomas Garnier wrote: >> This patch makes the GDT remapped pages read-only to prevent corruption. >> This change is done only on 64-bit. >> >> The native_load_tr_desc function was adapted to correctly handle a >> re

Re: [Xen-devel] [PATCH v7 3/3] x86: Make the GDT remapping read-only on 64-bit

2017-03-14 Thread Pavel Machek
On Tue 2017-03-14 10:05:08, Thomas Garnier wrote: > This patch makes the GDT remapped pages read-only to prevent corruption. > This change is done only on 64-bit. > > The native_load_tr_desc function was adapted to correctly handle a > read-only GDT. The LTR instruction always writes to the GDT TS

[Xen-devel] [PATCH v7 3/3] x86: Make the GDT remapping read-only on 64-bit

2017-03-14 Thread Thomas Garnier
This patch makes the GDT remapped pages read-only to prevent corruption. This change is done only on 64-bit. The native_load_tr_desc function was adapted to correctly handle a read-only GDT. The LTR instruction always writes to the GDT TSS entry. This generates a page fault if the GDT is read-only