Dave Jiang 061a785a11 ntb: Force physically contiguous allocation of rx ring buffers ... Physical addresses under IOVA on x86 platform are mapped contiguously as a side effect before the patch that removed CONFIG_DMA_REMAP. The NTB rx buffer ring is a single chunk DMA buffer that is allocated against the NTB PCI device. If the receive side is using a DMA device, then the buffers are remapped against the DMA device before being submitted via the dmaengine API. This scheme becomes a problem when the physical memory is discontiguous. When dma_map_page() is called on the kernel virtual address from the dma_alloc_coherent() call, the new IOVA mapping no longer points to all the physical memory allocated due to being discontiguous. Change dma_alloc_coherent() to dma_alloc_attrs() in order to force DMA_ATTR_FORCE_CONTIGUOUS attribute. This is the best fix for the circumstance. A potential future solution may be having the DMA mapping API providing a way to alias an existing IOVA mapping to a new device perhaps. This fix is not to fix the patch pointed to by the fixes tag, but to fix the issue arised in the ntb_transport driver on x86 platforms after the said patch is applied. Reported-by: Jerry Dai <jerry.dai@intel.com> Fixes: f5ff79fddf ("dma-mapping: remove CONFIG_DMA_REMAP") Tested-by: Jerry Dai <jerry.dai@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>		2024-09-20 10:51:25 -04:00
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hw	ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition	2024-09-20 10:50:38 -04:00
test	ntb_perf: Fix printk format	2024-09-20 10:50:38 -04:00
core.c	ntb: Constify struct bus_type	2024-09-20 10:50:38 -04:00
Kconfig
Makefile
msi.c
ntb_transport.c	ntb: Force physically contiguous allocation of rx ring buffers	2024-09-20 10:51:25 -04:00