This happens with both version 6.13.1 and the current tip of master (aca0a8669b538d58f018f95c9b22e6b3ec1ffe50). When I shut down X, the server segfaults in radeon_dri2_close_screen() when it tries to call drmFree(). With my current setup (acceleration disabled because firmware cannot be loaded), radeon_dri2_screen_init() is never called which is probably why radeon_dri2_close_screen() doesn't work correctly.
Mass closure: This bug has been untouched for more than six years, and is not obviously still valid. Please reopen this bug or file a new report if you continue to experience issues with current releases.
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