Re: [PATCH v2] spi: spi-mtk-nor: fix timeout calculation overflow

Hi!

On Tue, Sep 22, 2020 at 8:02 PM Mark Brown broonie@kernel.org wrote:

On Tue, Sep 22, 2020 at 07:49:02PM +0800, Chuanhong Guo wrote:

...

          if ((op->data.dir == SPI_MEM_DATA_IN) &&
              mtk_nor_match_read(op)) {

•                 // limit size to prevent timeout calculation overflow
  

•                 if (op->data.nbytes > 0x400000)
  

•                         op->data.nbytes = 0x400000;
  

If there's a limit on transfer sizes there should also be a max_transfer_size or max_message_size set (which we should pay attention to in the core for flash stuff but IIRC we didn't do that yet).

There's already a 6-byte max_message_size limit on this controller. spi-mem dma read is the only operation which allows such a long transfer.