Re: usbfs zerocopy broken on ARM/ARM64

2018-10-11 Thread Alan Stern
On Sun, 7 Oct 2018, Steve Markgraf wrote: > Hi, > > I'm the author of a userspace library that makes use of the usbfs > zerocopy-feature via libusb-1.0, and recently received a bug report that > garbage data is received with bulk transfers on ARM-based systems. > > When I debugged the issue, I f

usbfs zerocopy broken on ARM/ARM64

2018-10-07 Thread Steve Markgraf
Hi, I'm the author of a userspace library that makes use of the usbfs zerocopy-feature via libusb-1.0, and recently received a bug report that garbage data is received with bulk transfers on ARM-based systems. When I debugged the issue, I found out that the Kernel maps seemingly random memory to