Messages in this thread | | | Subject | Re: [PATCH] x86/xen: add physically contiguous check to xen_destroy_contiguous_region | From | Joe Jin <> | Date | Thu, 25 Oct 2018 21:17:10 -0700 |
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I did not realized range_straddles_page_boundary() only available on xen-swiotlb, please ignore this patch.
Sorry for the bother.
Thanks, Joe On 10/25/18 5:16 PM, Joe Jin wrote: > xen_destroy_contiguous_region() used to exchange physically > contiguous memory with hypervisor, but it does not verify > that the memory is physically contiguous or no, passing > non-contiguous memory to xen_destroy_contiguous_region() > will lead kernel panic. > > Signed-off-by: Joe Jin <joe.jin@oracle.com> > Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> > Cc: Juergen Gross <jgross@suse.com> > --- > arch/x86/xen/mmu_pv.c | 3 +++ > drivers/xen/swiotlb-xen.c | 3 +-- > 2 files changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c > index 70ea598a37d2..c2f081f8ebe3 100644 > --- a/arch/x86/xen/mmu_pv.c > +++ b/arch/x86/xen/mmu_pv.c > @@ -2649,6 +2649,9 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) > if (unlikely(order > MAX_CONTIG_ORDER)) > return; > > + if (range_straddles_page_boundary(pstart, PAGE_SIZE << order)) > + return; > + > vstart = (unsigned long)phys_to_virt(pstart); > memset((void *) vstart, 0, PAGE_SIZE << order); > > diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c > index f5c1af4ce9ab..432eeae02d7d 100644 > --- a/drivers/xen/swiotlb-xen.c > +++ b/drivers/xen/swiotlb-xen.c > @@ -357,8 +357,7 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, > /* Convert the size to actually allocated. */ > size = 1UL << (order + XEN_PAGE_SHIFT); > > - if (((dev_addr + size - 1 <= dma_mask)) || > - range_straddles_page_boundary(phys, size)) > + if (dev_addr + size - 1 <= dma_mask) > xen_destroy_contiguous_region(phys, order); > > xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); >
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