Hi Steve, I just discussed a problem with a qemu user on IRC, which boiled down to him trying to open an image file on cifs with O_DIRECT, but not using a directio mount. I understand that this probably isn't going to work anytime soon (if at all), but it resulted in a rather unhelpful failure mode. What happens is that cifs lets the open() call succeed even with the unsupported O_DIRECT on that mount, but then fails any I/O on the file descriptor. I believe this was introduced in commit dca69288 (which I think is otherwise pretty useful). With the old behaviour, qemu detected what's going on and suggested to use a non-O_DIRECT mode to the user, but with the new one, it got rather unhappy after failing to find a working O_DIRECT alignment and ran into an assertion failure... Now I'll certainly fix the latter in qemu, but I also think that the behaviour of cifs is rather surprising. Any chance that you can make open() with O_DIRECT fail again on non-directio mounts? Thanks, Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
