Re: [PATCH v2 1/2] dma-direct: check for overflows on 32 bit DMA addresses

2019-10-31 Thread Nicolas Saenz Julienne
On Wed, 2019-10-30 at 14:41 -0700, Christoph Hellwig wrote: > On Fri, Oct 18, 2019 at 01:00:43PM +0200, Nicolas Saenz Julienne wrote: > > +#ifndef CONFIG_ARCH_DMA_ADDR_T_64BIT > > + /* Check if DMA address overflowed */ > > + if (min(addr, addr + size - 1) < > > + __phys_to_dma(dev,

Re: [PATCH v2 1/2] dma-direct: check for overflows on 32 bit DMA addresses

2019-10-30 Thread Christoph Hellwig
On Fri, Oct 18, 2019 at 01:00:43PM +0200, Nicolas Saenz Julienne wrote: > +#ifndef CONFIG_ARCH_DMA_ADDR_T_64BIT > + /* Check if DMA address overflowed */ > + if (min(addr, addr + size - 1) < > + __phys_to_dma(dev, (phys_addr_t)(min_low_pfn << PAGE_SHIFT))) > +

[PATCH v2 1/2] dma-direct: check for overflows on 32 bit DMA addresses

2019-10-18 Thread Nicolas Saenz Julienne
As seen on the new Raspberry Pi 4 and sta2x11's DMA implementation it is possible for a device configured with 32 bit DMA addresses and a partial DMA mapping located at the end of the address space to overflow. It happens when a higher physical address, not DMAable, is translated to it's DMA