On Tue, Jun 25, 2019 at 11:46:23AM +0900, Damien Le Moal wrote: > To allow the SCSI subsystem scsi_execute_req() function to issue > requests using large buffers that are better allocated with vmalloc() > rather than kmalloc(), modify bio_map_kern() to allow passing a buffer > allocated with the vmalloc() function. To do so, simply test the buffer > address using is_vmalloc_addr() and use vmalloc_to_page() instead of > virt_to_page() to obtain the pages of vmalloc-ed buffers. This is broken on architectures with VIVT caches. You need to flush and invalidate the caches based on the virtual address on those before performing DMA operations.
