http://bugzilla.opensuse.org/show_bug.cgi?id=1033080 Bug ID: 1033080 Summary: Change in sizeof(snd_pcm_direct_share_t) breaks container that wants to reach dmix via shm Classification: openSUSE Product: openSUSE Distribution Version: Leap 42.2 Hardware: x86-64 OS: openSUSE 42.2 Status: NEW Severity: Normal Priority: P5 - None Component: Sound Assignee: tiwai@suse.com Reporter: maarten@treewalker.org QA Contact: qa-bugs@suse.de Found By: --- Blocker: --- I run applications inside a Docker container, which want to play audio via ALSA. These applications use their own copy of alsa-lib. This setup used to work by sharing the IPC resources between host and container, but broke during a recent openSUSE upgrade. I did some digging and found why: in the update from libasound2-1.1.3-6 to libasound2-1.1.3-8, the size of struct snd_pcm_direct_share_t changed from 488 bytes to 496 bytes. This size is checked as part of the SND_PCM_DIRECT_MAGIC signature to determine whether the shared memory segment belongs to dmix or not. So if the size of the struct changes, the shm segment is rejected and alsa-lib cannot play audio. For the moment, I forced a downgrade back to libasound2-1.1.3-6 and now sound from within containers works again. If it's feasible to restore the struct to its former layout, that would be much appreciated. Otherwise, having this incompatibility documented by this bug report might at least save someone else some time figuring out the problem. -- You are receiving this mail because: You are on the CC list for the bug.