On 05/02/2014 11:07 AM, Kamal Mostafa wrote: > Dirk Behme points out that this "Cc: stable" commit breaks the > lttng-modules userspace API when applied to stable kernels. Stable > versions 3.2, 3.8, 3.11, and 3.13 (at least) have all queued it: > > af5040da01ef980670b3741b3e10733ee3e33566 > blktrace: fix accounting of partially completed requests > > > On Thu, 2014-05-01 at 10:28 +0200, Dirk Behme wrote: >> [...] might break the build of the user space lttng-modules >> (lttng-probe-block.c) due the the API change of >> trace_block_rq_complete(). > >> [...] On the other hand, looking into the lttng-modules git >> https://urldefense.proofpoint.com/v1/url?u=http://git.lttng.org/?p%3Dlttng-modules.git%3Ba%3Dcommitdiff%3Bh%3D1c53e689434a6bdd7dc3f54c07bfb72750d1d24c&k=ZVNjlDMF0FElm4dQtryO4A%3D%3D%0A&r=3JMVyziIyZtZ5cv9eWNLwQ%3D%3D%0A&m=D2KNsLv3tBvujVWNGEitr5chlVfb7ID4dAFp7olp%2Blg%3D%0A&s=c0eb7f0e5e827dce7b172578d29632d4092d1572c475a54109cefc97ad37e789 >> looks like this is the necessary user space adaption to the kernel >> change? So this looks like that lttng-modules expects a KERNEL_VERSION >>> = (3,15,0) to have this commit? > > > My inclination is that we probably need to revert/drop "af5040d > blktrace: fix accounting..." from the stable kernels to unbreak the > userspace API. > > I'm looking for opinions and advice from other stable maintainers and/or > lttng folks. This is crazy. The trace point was wrong for partial completions, it's fixing a bug. I'm all for keeping user space compatibility, but this is a source level change. -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html