On Wed, May 29, 2019 at 01:28:41PM +0300, laurentiu.tudor@xxxxxxx wrote: > From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> > > In preparation for dropping the existing "coherent" dma mem declaration > APIs, replace the current dma_declare_coherent_memory() based mechanism > with the creation of a genalloc pool that will be used in the OHCI > subsystem as replacement for the DMA APIs. > > For context, see thread here: https://lkml.org/lkml/2019/4/22/357 > > Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> This patch results in usb access failures when trying to boot from the sm501-usb controller on sh4 with qemu. usb 1-2.1: reset full-speed USB device number 4 using sm501-usb sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=0x00 sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 08 7c 00 00 f0 00 print_req_error: I/O error, dev sda, sector 2172 flags 80700 usb 1-2.1: reset full-speed USB device number 4 using sm501-usb sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=0x00 sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 01 da 00 00 f0 00 print_req_error: I/O error, dev sda, sector 474 flags 84700 usb 1-2.1: reset full-speed USB device number 4 using sm501-usb sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=0x00 sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 02 da 00 00 f0 00 print_req_error: I/O error, dev sda, sector 730 flags 84700 usb 1-2.1: reset full-speed USB device number 4 using sm501-usb sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=0x00 sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 0b 50 00 00 f0 00 print_req_error: I/O error, dev sda, sector 2896 flags 84700 Qemu command line is: The qemu command line is: qemu-system-sh4 -M r2d \ -kernel ./arch/sh/boot/zImage \ -snapshot \ -usb -device usb-storage,drive=d0 \ -drive file=rootfs.ext2,if=none,id=d0,format=raw \ -append 'panic=-1 slub_debug=FZPUA root=/dev/sda rootwait console=ttySC1,115200 earlycon=scif,mmio16,0xffe80000 noiotrap' \ -serial null -serial stdio \ -net nic,model=rtl8139 -net user -nographic -monitor null Reverting this patch as well as "USB: drop HCD_LOCAL_MEM flag" fixes the problem. Reverting "USB: drop HCD_LOCAL_MEM flag" alone does not help. Guenter