On Thu, Jan 31, 2019 at 09:43:42AM -0800, Linus Torvalds wrote: > On Thu, Jan 31, 2019 at 9:06 AM Jarkko Sakkinen > <jarkko.sakki...@linux.intel.com> wrote: > > > > Found something that *does* fix the issue. If I replace memcpy_*io() > > calls with regular memcpy(), the driver works and all my tests pass. > > That's not surprising, since that's what we used to do. And it's > horribly wrong because "memcpy()" can do things that are horribly > wrong on IO accesses. Like doing them twice, but alternatively also > "copy one byte at a time" which generally works, but is horrendously > slow for IO.
Yup, was just a sanity check. > Can you check *which* memcpy_*io() triggers the issue? Maybe by > "bisecting" them (first perhaps on a file-by-file basis, and then > within a file). Already did that. See my follow-up. /Jarkko