xen: swiotlb: Use swiotlb bouncing if kmalloc allocation demands it

commit cd9c058489053e172a6654cad82ee936d1b09fab upstream.

Xen swiotlb support was missed when the patch set starting with
4ab5f8ec7d ("mm/slab: decouple ARCH_KMALLOC_MINALIGN from
ARCH_DMA_MINALIGN") was merged.

When running Xen on iMX8QXP, a SoC without IOMMU, the effect was that USB
transfers ended up corrupted when there was more than one URB inflight at
the same time.

Add a call to dma_kmalloc_needs_bounce() to make sure that allocations too
small for DMA get bounced via swiotlb.

Closes: https://lore.kernel.org/linux-usb/ab2776f0-b838-4cf6-a12a-c208eb6aad59@actia.se/
Fixes: 4ab5f8ec7d ("mm/slab: decouple ARCH_KMALLOC_MINALIGN from ARCH_DMA_MINALIGN")
Cc: stable@kernel.org # v6.5+
Signed-off-by: John Ernberg <john.ernberg@actia.se>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20250502114043.1968976-2-john.ernberg@actia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
John Ernberg
2025-05-02 11:40:55 +00:00
committed by Greg Kroah-Hartman
parent 2ed98e89eb
commit ffa14d4dc7

View File

@@ -216,6 +216,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
* buffering it.
*/
if (dma_capable(dev, dev_addr, size, true) &&
!dma_kmalloc_needs_bounce(dev, size, dir) &&
!range_straddles_page_boundary(phys, size) &&
!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
!is_swiotlb_force_bounce(dev))