[Xen-changelog] [xen master] dom0/pvh: align allocation and mapping order to start address

[patchbot@xxxxxxx]

commit dc0b0b1f2d5792ecd9e26f2e65b36682f8ec2b27
Author:     Roger Pau Monné <roger.pau@xxxxxxxxxx>
AuthorDate: Mon Feb 18 13:42:51 2019 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Feb 18 13:42:51 2019 +0100

    dom0/pvh: align allocation and mapping order to start address
    
    The p2m and iommu mapping code always had the requirement that
    addresses and orders must be aligned when populating the p2m or the
    iommu page tables.
    
    PVH dom0 builder didn't take this requirement into account, and can
    call into the p2m/iommu mapping helpers with addresses and orders that
    are not aligned.
    
    Fix this by making sure the orders passed to the physmap population
    helpers are always aligned to the guest address to be populated.
    
    Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
    Reviewed-by: Wei Liu <wei.liu2@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
    Release-acked-by: Juergen Gross <jgross@xxxxxxxx>
---
 xen/arch/x86/hvm/dom0_build.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/xen/arch/x86/hvm/dom0_build.c b/xen/arch/x86/hvm/dom0_build.c
index 51cf490811..a571d15c13 100644
--- a/xen/arch/x86/hvm/dom0_build.c
+++ b/xen/arch/x86/hvm/dom0_build.c
@@ -152,6 +152,8 @@ static int __init pvh_populate_memory_range(struct domain 
*d,
 
         order = get_order_from_pages(end - start + 1);
         order = min(order ? order - 1 : 0, max_order);
+        /* The order allocated and populated must be aligned to the address. */
+        order = min(order, start ? find_first_set_bit(start) : MAX_ORDER);
         page = alloc_domheap_pages(d, order, dom0_memflags | MEMF_no_scrub);
         if ( page == NULL )
         {
--
generated by git-patchbot for /home/xen/git/xen.git#master

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/xen-changelog