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| author | Alex Nixon <alex.nixon@citrix.com> | 2010-02-19 13:31:06 -0500 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2010-06-07 14:33:13 -0400 |
| commit | 7347b4082e55ac4a673f06a0a0ce25c37273c9ec (patch) | |
| tree | b39ef6d8aaf3081b97a12fa06ca86ffb668d1b68 /arch/x86/xen/enlighten.c | |
| parent | c0011dbfce69467b23b08fb4a64c39a409a935fb (diff) | |
| download | linux-7347b4082e55ac4a673f06a0a0ce25c37273c9ec.tar.gz linux-7347b4082e55ac4a673f06a0a0ce25c37273c9ec.tar.bz2 linux-7347b4082e55ac4a673f06a0a0ce25c37273c9ec.zip | |
xen: Allow unprivileged Xen domains to create iomap pages
PV DomU domains are allowed to map hardware MFNs for PCI passthrough,
but are not generally allowed to map raw machine pages. In particular,
various pieces of code try to map DMI and ACPI tables in the ISA ROM
range. We disallow _PAGE_IOMAP for those mappings, so that they are
redirected to a set of local zeroed pages we reserve for that purpose.
[ Impact: prevent passthrough of ISA space, as we only allow PCI ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'arch/x86/xen/enlighten.c')
| -rw-r--r-- | arch/x86/xen/enlighten.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 65d8d79b46a8..3254e8bc4cd7 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1145,6 +1145,10 @@ asmlinkage void __init xen_start_kernel(void) pgd = (pgd_t *)xen_start_info->pt_base; + if (!xen_initial_domain()) + __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); + + __supported_pte_mask |= _PAGE_IOMAP; /* Don't do the full vcpu_info placement stuff until we have a possible map and a non-dummy shared_info. */ per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; |