The fix for bug 754568 has caused some rendering corruption in Emacs. Specifically, when preparing a surface for software rendering, the pixmap header is leaving the size as is. A workaround for the corruption is to set the size to size of the pixmap backing images for the surface. Which suggests that the bug might be that rendering to a pixmap is offset, and then the pixmap itself is also rendered with an offset origin, leading to excessive clipping.
If this is not fixed by 17 GOLD, suggest a release note about the emacs corruption.
Given the approaching end-of-life for F17, and that F17 qxl hasn't been updated in a year, I don't think this bug will be fixed. If anyone can reproduce with F19, please reopen.