# git-describe --contains 4 messages from 2017-08-11 to 2017-08-13. Participants: Davide Cavallari, Nicolas Morey-Chaisemartin, Andreas Schwab. Thread: https://gitlist.dev/t/46565 ## Davide Cavallari, 2017-08-11 06:50 Subject: git-describe --contains Message-ID: URL: https://gitlist.dev/e/CANOKeme4j9fHuQoQY3MQeoNuietjez8m1wPkAO%3D1eSDtHG3J9w%40mail.gmail.com ``` Please help me understand how this command works. There is one case in the linux kernel repository that puzzles me. Let's consider patch "drm/i915/ execlists: Reset RING registers upon resume" [1]. This patch was committed 641 commits after version 4.8-rc2: ~$ git describe bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae v4.8-rc2-641-gbafb2f7d4755 So I would expect to find it in version 4.8-rc3 and later versions. However, if I search for the tag that follows (and hence contains) that commit, I do not find version 4.8-rc3, nor version 4.8, nor version 4.9, but 4.10-rc1: ~$ git describe --contains bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae v4.10-rc1~154^2~44^2~178 Why? Why not v4.8-rc3? This means that the patch has been included neither in v4.8 nor in v4.9, but only in version 4.10-rc1, right? Why so much time was needed, considering it was the 621st commit on top ov v4.8-rc2? BTW, what are the numbers 154^2~44^2~178 that follow the tag name? Thanks & Regards, Davide [1] https://patchwork.freedesktop.org/patch/111587/ ``` ## Nicolas Morey-Chaisemartin, 2017-08-11 09:12 Subject: Re: git-describe --contains Message-ID: <476ddcbb-6d66-bc6b-5fbd-aa43851dec30@suse.de> URL: https://gitlist.dev/e/476ddcbb-6d66-bc6b-5fbd-aa43851dec30%40suse.de In-Reply-To: ``` Le 11/08/2017 à 08:50, Davide Cavallari a écrit : > Please help me understand how this command works. There is one case in the > linux kernel repository that puzzles me. Let's consider patch "drm/i915/ > execlists: Reset RING registers upon resume" [1]. This patch was committed 641 > commits after version 4.8-rc2: > > ~$ git describe bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae > v4.8-rc2-641-gbafb2f7d4755 > > So I would expect to find it in version 4.8-rc3 and later versions. > > However, if I search for the tag that follows (and hence contains) that > commit, I do not find version 4.8-rc3, nor version 4.8, nor version 4.9, but > 4.10-rc1: > > ~$ git describe --contains bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae > v4.10-rc1~154^2~44^2~178 > > Why? Why not v4.8-rc3? This means that the patch has been included neither in > v4.8 nor in v4.9, but only in version 4.10-rc1, right? Why so much time was > needed, considering it was the 621st commit on top ov v4.8-rc2? Because it was not in v4.8-rc3. This probably means it was applied on a branch that started from somewhere between 4.8-rc2 and 4.8-rc3 but it was only merge into master after v4.9 was released > > BTW, what are the numbers 154^2~44^2~178 that follow the tag name? This is due to merges. You have basically a roadmap to go up the ancestry graph. ~154 means 154 commit before the tag ^2 means the 2nd parent of this commit. and so on... The format is detailed (among other tings) in man gitrevisions Nicolas ``` ## Andreas Schwab, 2017-08-11 09:39 Subject: Re: git-describe --contains Message-ID: <87shgyh2a3.fsf@linux-m68k.org> URL: https://gitlist.dev/e/87shgyh2a3.fsf%40linux-m68k.org In-Reply-To: ``` On Aug 11 2017, Davide Cavallari wrote: > Please help me understand how this command works. There is one case in the > linux kernel repository that puzzles me. Let's consider patch "drm/i915/ > execlists: Reset RING registers upon resume" [1]. This patch was committed 641 > commits after version 4.8-rc2: > > ~$ git describe bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae > v4.8-rc2-641-gbafb2f7d4755 > > So I would expect to find it in version 4.8-rc3 and later versions. > > However, if I search for the tag that follows (and hence contains) that > commit, I do not find version 4.8-rc3, nor version 4.8, nor version 4.9, but > 4.10-rc1: > > ~$ git describe --contains bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae > v4.10-rc1~154^2~44^2~178 > > Why? Why not v4.8-rc3? This means that the patch has been included neither in > v4.8 nor in v4.9, but only in version 4.10-rc1, right? Why so much time was > needed, considering it was the 621st commit on top ov v4.8-rc2? You have to ask that the maintainers of the drm subsystem. If you look at commit 5481e27f6fd06b7cb902072e81d6b083db8155eb you see that the branch containing the above commit was merged into a branch that follows v4.9-rc2, which eventually was merged into v4.10-rc1. > BTW, what are the numbers 154^2~44^2~178 that follow the tag name? See git-rev-parse(1). '~N' means to go back N parents, ^N means to pick parent N of a merge commit. Andreas. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different." ``` ## Davide Cavallari, 2017-08-13 06:39 Subject: Re: git-describe --contains Message-ID: URL: https://gitlist.dev/e/CANOKemdSA0OgaLosQ6ez%3DYPGJWOCCax6qQ5s%3DXSv1DQ4DwuMUw%40mail.gmail.com In-Reply-To: ``` Thanks Andreas and Nicholas, I'll check it out. ```