docs/submittingpatches.html - platform/external/mesa3d - Git at Google

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   <h1>The Mesa 3D Graphics Library</h1>
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 <iframe src="contents.html"></iframe>
 <div class="content">

 <h1>Submitting patches</h1>


 <ul>
 <li><a href="#guidelines">Basic guidelines</a>
 <li><a href="#formatting">Patch formatting</a>
 <li><a href="#testing">Testing Patches</a>
 <li><a href="#mailing">Mailing Patches</a>
 <li><a href="#reviewing">Reviewing Patches</a>
 <li><a href="#nominations">Nominating a commit for a stable branch</a>
 <li><a href="#criteria">Criteria for accepting patches to the stable branch</a>
 <li><a href="#gittips">Git tips</a>
 </ul>

 <h2 id="guidelines">Basic guidelines</h2>

 <ul>
 <li>Patches should not mix code changes with code formatting changes (except,
 perhaps, in very trivial cases.)
 <li>Code patches should follow Mesa
 <a href="codingstyle.html" target="_parent">coding conventions</a>.
 <li>Whenever possible, patches should only effect individual Mesa/Gallium
 components.
 <li>Patches should never introduce build breaks and should be bisectable (see
 <code>git bisect</code>.)
 <li>Patches should be properly <a href="#formatting">formatted</a>.
 <li>Patches should be sufficiently <a href="#testing">tested</a> before submitting.
 <li>Patches should be submitted to <a href="#mailing">mesa-dev</a>
 for <a href="#reviewing">review</a> using <code>git send-email</code>.

 </ul>

 <h2 id="formatting">Patch formatting</h2>

 <ul>
 <li>Lines should be limited to 75 characters or less so that git logs
 displayed in 80-column terminals avoid line wrapping.  Note that git
 log uses 4 spaces of indentation (4 + 75 &lt; 80).
 <li>The first line should be a short, concise summary of the change prefixed
 with a module name.  Examples:
 <pre>
     mesa: Add support for querying GL_VERTEX_ATTRIB_ARRAY_LONG

     gallium: add PIPE_CAP_DEVICE_RESET_STATUS_QUERY

     i965: Fix missing type in local variable declaration.
 </pre>
 <li>Subsequent patch comments should describe the change in more detail,
 if needed.  For example:
 <pre>
     i965: Remove end-of-thread SEND alignment code.

     This was present in Eric's initial implementation of the compaction code
     for Sandybridge (commit 077d01b6). There is no documentation saying this
     is necessary, and removing it causes no regressions in piglit on any
     platform.
 </pre>
 <li>A "Signed-off-by:" line is not required, but not discouraged either.
 <li>If a patch address a bugzilla issue, that should be noted in the
 patch comment.  For example:
 <pre>
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89689
 </pre>
 <li>If there have been several revisions to a patch during the review
 process, they should be noted such as in this example:
 <pre>
     st/mesa: add ARB_texture_stencil8 support (v4)

     if we support stencil texturing, enable texture_stencil8
     there is no requirement to support native S8 for this,
     the texture can be converted to x24s8 fine.

     v2: fold fixes from Marek in:
        a) put S8 last in the list
        b) fix renderable to always test for d/s renderable
         fixup the texture case to use a stencil only format
         for picking the format for the texture view.
     v3: hit fallback for getteximage
     v4: put s8 back in front, it shouldn't get picked now (Ilia)
 </pre>
 <li>If someone tested your patch, document it with a line like this:
 <pre>
     Tested-by: Joe Hacker &lt;jhacker@foo.com&gt;
 </pre>
 <li>If the patch was reviewed (usually the case) or acked by someone,
 that should be documented with:
 <pre>
     Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
     Acked-by: Joe Hacker &lt;jhacker@foo.com&gt;
 </pre>
 <li>If sending later revision of a patch, add all the tags - ack, r-b,
 Cc: mesa-stable and/or other. This provides reviewers with quick feedback if the
 patch has already been reviewed.
 <li>In order for your patch to reach the prospective reviewer easier/faster,
 use the script scripts/get_reviewer.pl to get a list of individuals and include
 them in the CC list.
 <br>
 Please use common sense and do <strong>not</strong> blindly add everyone.
 <br>
 <pre>
     $ scripts/get_reviewer.pl --help # to get the the help screen
     $ scripts/get_reviewer.pl -f src/egl/drivers/dri2/platform_android.c
     Rob Herring <robh@kernel.org> (reviewer:ANDROID EGL SUPPORT,added_lines:188/700=27%,removed_lines:58/283=20%)
     Tomasz Figa <tfiga@chromium.org> (reviewer:ANDROID EGL SUPPORT,authored:12/41=29%,added_lines:308/700=44%,removed_lines:115/283=41%)
     Emil Velikov <emil.l.velikov@gmail.com> (authored:13/41=32%,removed_lines:76/283=27%)
 </pre>
 </ul>


 <h2 id="testing">Testing Patches</h2>

 <p>
 It should go without saying that patches must be tested.  In general,
 do whatever testing is prudent.
 </p>

 <p>
 You should always run the Mesa test suite before submitting patches.
 The test suite can be run using the 'make check' command. All tests
 must pass before patches will be accepted, this may mean you have
 to update the tests themselves.
 </p>

 <p>
 Whenever possible and applicable, test the patch with
 <a href="http://piglit.freedesktop.org">Piglit</a> and/or
 <a href="https://android.googlesource.com/platform/external/deqp/">dEQP</a>
 to check for regressions.
 </p>


 <h2 id="mailing">Mailing Patches</h2>

 <p>
 Patches should be sent to the mesa-dev mailing list for review:
 <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev">
 mesa-dev@lists.freedesktop.org</a>.
 When submitting a patch make sure to use
 <a href="https://git-scm.com/docs/git-send-email">git send-email</a>
 rather than attaching patches to emails. Sending patches as
 attachments prevents people from being able to provide in-line review
 comments.
 </p>

 <p>
 When submitting follow-up patches you can use --in-reply-to to make v2, v3,
 etc patches show up as replies to the originals. This usually works well
 when you're sending out updates to individual patches (as opposed to
 re-sending the whole series). Using --in-reply-to makes
 it harder for reviewers to accidentally review old patches.
 </p>

 <p>
 When submitting follow-up patches you should also login to
 <a href="https://patchwork.freedesktop.org">patchwork</a> and change the
 state of your old patches to Superseded.
 </p>

 <h2 id="reviewing">Reviewing Patches</h2>

 <p>
 When you've reviewed a patch on the mailing list, please be unambiguous
 about your review.  That is, state either
 </p>
 <pre>
     Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
 </pre>
 or
 <pre>
     Acked-by: Joe Hacker &lt;jhacker@foo.com&gt;
 </pre>
 <p>
 Rather than saying just "LGTM" or "Seems OK".
 </p>

 <p>
 If small changes are suggested, it's OK to say something like:
 </p>
 <pre>
    With the above fixes, Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
 </pre>
 <p>
 which tells the patch author that the patch can be committed, as long
 as the issues are resolved first.
 </p>


 <h2 id="nominations">Nominating a commit for a stable branch</h2>

 <p>
 There are three ways to nominate patch for inclusion of the stable branch and
 release.
 </p>
 <ul>
 <li> By adding the Cc: mesa-stable@ tag as described below.
 <li> Sending the commit ID (as seen in master branch) to the mesa-stable@ mailing list.
 <li> Forwarding the patch from the mesa-dev@ mailing list.
 </li>
 </ul>
 <p>
 Note: resending patch identical to one on mesa-dev@ or one that differs only
 by the extra mesa-stable@ tag is <strong>not</strong> recommended.
 </p>


 <h3 id="thetag">The stable tag</h3>

 <p>
 If you want a commit to be applied to a stable branch,
 you should add an appropriate note to the commit message.
 </p>

 <p>
 Here are some examples of such a note:
 </p>
 <ul>
   <li>CC: &lt;mesa-stable@lists.freedesktop.org&gt;</li>
   <li>CC: "9.2 10.0" &lt;mesa-stable@lists.freedesktop.org&gt;</li>
   <li>CC: "10.0" &lt;mesa-stable@lists.freedesktop.org&gt;</li>
 </ul>

 Simply adding the CC to the mesa-stable list address is adequate to nominate
 the commit for the most-recently-created stable branch. It is only necessary
 to specify a specific branch name, (such as "9.2 10.0" or "10.0" in the
 examples above), if you want to nominate the commit for an older stable
 branch. And, as in these examples, you can nominate the commit for the older
 branch in addition to the more recent branch, or nominate the commit
 exclusively for the older branch.

 This "CC" syntax for patch nomination will cause patches to automatically be
 copied to the mesa-stable@ mailing list when you use "git send-email" to send
 patches to the mesa-dev@ mailing list. If you prefer using --suppress-cc that
 won't have any effect negative effect on the patch nomination.

 <p>
 Note: by removing the tag [as the commit is pushed] the patch is
 <strong>explicitly</strong> rejected from inclusion in the stable branch(es).
 <br>
 Thus, drop the line <strong>only</strong> if you want to cancel the nomination.
 </p>

 <h2 id="criteria">Criteria for accepting patches to the stable branch</h2>

 Mesa has a designated release manager for each stable branch, and the release
 manager is the only developer that should be pushing changes to these
 branches. Everyone else should simply nominate patches using the mechanism
 described above.

 The stable-release manager will work with the list of nominated patches, and
 for each patch that meets the criteria below will cherry-pick the patch with:
 <code>git cherry-pick -x &lt;commit&gt;</code>. The <code>-x</code> option is
 important so that the picked patch references the commit ID of the original
 patch.

 The stable-release manager may at times need to force-push changes to the
 stable branches, for example, to drop a previously-picked patch that was later
 identified as causing a regression). These force-pushes may cause changes to
 be lost from the stable branch if developers push things directly. Consider
 yourself warned.

 The stable-release manager is also given broad discretion in rejecting patches
 that have been nominated for the stable branch. The most basic rule is that
 the stable branch is for bug fixes only, (no new features, no
 regressions). Here is a non-exhaustive list of some reasons that a patch may
 be rejected:

 <ul>
   <li>Patch introduces a regression. Any reported build breakage or other
   regression caused by a particular patch, (game no longer work, piglit test
   changes from PASS to FAIL), is justification for rejecting a patch.</li>

   <li>Patch is too large, (say, larger than 100 lines)</li>

   <li>Patch is not a fix. For example, a commit that moves code around with no
   functional change should be rejected.</li>

   <li>Patch fix is not clearly described. For example, a commit message
   of only a single line, no description of the bug, no mention of bugzilla,
   etc.</li>

   <li>Patch has not obviously been reviewed, For example, the commit message
   has no Reviewed-by, Signed-off-by, nor Tested-by tags from anyone but the
   author.</li>

   <li>Patch has not already been merged to the master branch. As a rule, bug
   fixes should never be applied first to a stable branch. Patches should land
   first on the master branch and then be cherry-picked to a stable
   branch. (This is to avoid future releases causing regressions if the patch
   is not also applied to master.) The only things that might look like
   exceptions would be backports of patches from master that happen to look
   significantly different.</li>

   <li>Patch depends on too many other patches. Ideally, all stable-branch
   patches should be self-contained. It sometimes occurs that a single, logical
   bug-fix occurs as two separate patches on master, (such as an original
   patch, then a subsequent fix-up to that patch). In such a case, these two
   patches should be squashed into a single, self-contained patch for the
   stable branch. (Of course, if the squashing makes the patch too large, then
   that could be a reason to reject the patch.)</li>

   <li>Patch includes new feature development, not bug fixes. New OpenGL
   features, extensions, etc. should be applied to Mesa master and included in
   the next major release. Stable releases are intended only for bug fixes.

   Note: As an exception to this rule, the stable-release manager may accept
   hardware-enabling "features". For example, backports of new code to support
   a newly-developed hardware product can be accepted if they can be reasonably
   determined to not have effects on other hardware.</li>

   <li>Patch is a performance optimization. As a rule, performance patches are
   not candidates for the stable branch. The only exception might be a case
   where an application's performance was recently severely impacted so as to
   become unusable. The fix for this performance regression could then be
   considered for a stable branch. The optimization must also be
   non-controversial and the patches still need to meet the other criteria of
   being simple and self-contained</li>

   <li>Patch introduces a new failure mode (such as an assert). While the new
   assert might technically be correct, for example to make Mesa more
   conformant, this is not the kind of "bug fix" we want in a stable
   release. The potential problem here is that an OpenGL program that was
   previously working, (even if technically non-compliant with the
   specification), could stop working after this patch. So that would be a
   regression that is unacceptable for the stable branch.</li>
 </ul>

 <h2 id="gittips">Git tips</h2>

 <ul>
 <li><code>git rebase -i ...</code> is your friend. Don't be afraid to use it.
 <li>Apply a fixup to commit FOO.
 <pre>
     git add ...
     git commit --fixup=FOO
     git rebase -i --autosquash ...
 </pre>
 <li>Test for build breakage between patches e.g last 8 commits.
 <pre>
     git rebase -i --exec="make -j4" HEAD~8
 </pre>
 <li>Sets the default mailing address for your repo.
 <pre>
     git config --local sendemail.to mesa-dev@lists.freedesktop.org
 </pre>
 <li> Add version to subject line of patch series in this case for the last 8
 commits before sending.
 <pre>
     git send-email --subject-prefix="PATCH v4" HEAD~8
     git send-email -v4 @~8 # shorter version, inherited from git format-patch
 </pre>
 <li> Configure git to use the get_reviewer.pl script interactively. Thus you
 can avoid adding the world to the CC list.
 <pre>
     git config sendemail.cccmd "./scripts/get_reviewer.pl -i"
 </pre>
 </ul>


 </div>
 </body>
 </html>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
	<html lang="en">
	<head>
	<meta http-equiv="content-type" content="text/html; charset=utf-8">
	<title>Submitting patches</title>
	<link rel="stylesheet" type="text/css" href="mesa.css">
	</head>
	<body>

	<div class="header">
	<h1>The Mesa 3D Graphics Library</h1>
	</div>

	<iframe src="contents.html"></iframe>
	<div class="content">

	<h1>Submitting patches</h1>


	<ul>
	<li><a href="#guidelines">Basic guidelines</a>
	<li><a href="#formatting">Patch formatting</a>
	<li><a href="#testing">Testing Patches</a>
	<li><a href="#mailing">Mailing Patches</a>
	<li><a href="#reviewing">Reviewing Patches</a>
	<li><a href="#nominations">Nominating a commit for a stable branch</a>
	<li><a href="#criteria">Criteria for accepting patches to the stable branch</a>
	<li><a href="#gittips">Git tips</a>
	</ul>

	<h2 id="guidelines">Basic guidelines</h2>

	<ul>
	<li>Patches should not mix code changes with code formatting changes (except,
	perhaps, in very trivial cases.)
	<li>Code patches should follow Mesa
	<a href="codingstyle.html" target="_parent">coding conventions</a>.
	<li>Whenever possible, patches should only effect individual Mesa/Gallium
	components.
	<li>Patches should never introduce build breaks and should be bisectable (see
	<code>git bisect</code>.)
	<li>Patches should be properly <a href="#formatting">formatted</a>.
	<li>Patches should be sufficiently <a href="#testing">tested</a> before submitting.
	<li>Patches should be submitted to <a href="#mailing">mesa-dev</a>
	for <a href="#reviewing">review</a> using <code>git send-email</code>.

	</ul>

	<h2 id="formatting">Patch formatting</h2>

	<ul>
	<li>Lines should be limited to 75 characters or less so that git logs
	displayed in 80-column terminals avoid line wrapping. Note that git
	log uses 4 spaces of indentation (4 + 75 < 80).
	<li>The first line should be a short, concise summary of the change prefixed
	with a module name. Examples:
	<pre>
	mesa: Add support for querying GL_VERTEX_ATTRIB_ARRAY_LONG

	gallium: add PIPE_CAP_DEVICE_RESET_STATUS_QUERY

	i965: Fix missing type in local variable declaration.
	</pre>
	<li>Subsequent patch comments should describe the change in more detail,
	if needed. For example:
	<pre>
	i965: Remove end-of-thread SEND alignment code.

	This was present in Eric's initial implementation of the compaction code
	for Sandybridge (commit 077d01b6). There is no documentation saying this
	is necessary, and removing it causes no regressions in piglit on any
	platform.
	</pre>
	<li>A "Signed-off-by:" line is not required, but not discouraged either.
	<li>If a patch address a bugzilla issue, that should be noted in the
	patch comment. For example:
	<pre>
	Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89689
	</pre>
	<li>If there have been several revisions to a patch during the review
	process, they should be noted such as in this example:
	<pre>
	st/mesa: add ARB_texture_stencil8 support (v4)

	if we support stencil texturing, enable texture_stencil8
	there is no requirement to support native S8 for this,
	the texture can be converted to x24s8 fine.

	v2: fold fixes from Marek in:
	a) put S8 last in the list
	b) fix renderable to always test for d/s renderable
	fixup the texture case to use a stencil only format
	for picking the format for the texture view.
	v3: hit fallback for getteximage
	v4: put s8 back in front, it shouldn't get picked now (Ilia)
	</pre>
	<li>If someone tested your patch, document it with a line like this:
	<pre>
	Tested-by: Joe Hacker <jhacker@foo.com>
	</pre>
	<li>If the patch was reviewed (usually the case) or acked by someone,
	that should be documented with:
	<pre>
	Reviewed-by: Joe Hacker <jhacker@foo.com>
	Acked-by: Joe Hacker <jhacker@foo.com>
	</pre>
	<li>If sending later revision of a patch, add all the tags - ack, r-b,
	Cc: mesa-stable and/or other. This provides reviewers with quick feedback if the
	patch has already been reviewed.
	<li>In order for your patch to reach the prospective reviewer easier/faster,
	use the script scripts/get_reviewer.pl to get a list of individuals and include
	them in the CC list.
	<br>
	Please use common sense and do <strong>not</strong> blindly add everyone.
	<br>
	<pre>
	$ scripts/get_reviewer.pl --help # to get the the help screen
	$ scripts/get_reviewer.pl -f src/egl/drivers/dri2/platform_android.c
	Rob Herring <robh@kernel.org> (reviewer:ANDROID EGL SUPPORT,added_lines:188/700=27%,removed_lines:58/283=20%)
	Tomasz Figa <tfiga@chromium.org> (reviewer:ANDROID EGL SUPPORT,authored:12/41=29%,added_lines:308/700=44%,removed_lines:115/283=41%)
	Emil Velikov <emil.l.velikov@gmail.com> (authored:13/41=32%,removed_lines:76/283=27%)
	</pre>
	</ul>



	<h2 id="testing">Testing Patches</h2>

	<p>
	It should go without saying that patches must be tested. In general,
	do whatever testing is prudent.
	</p>

	<p>
	You should always run the Mesa test suite before submitting patches.
	The test suite can be run using the 'make check' command. All tests
	must pass before patches will be accepted, this may mean you have
	to update the tests themselves.
	</p>

	<p>
	Whenever possible and applicable, test the patch with
	<a href="http://piglit.freedesktop.org">Piglit</a> and/or
	<a href="https://android.googlesource.com/platform/external/deqp/">dEQP</a>
	to check for regressions.
	</p>


	<h2 id="mailing">Mailing Patches</h2>

	<p>
	Patches should be sent to the mesa-dev mailing list for review:
	<a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev">
	mesa-dev@lists.freedesktop.org</a>.
	When submitting a patch make sure to use
	<a href="https://git-scm.com/docs/git-send-email">git send-email</a>
	rather than attaching patches to emails. Sending patches as
	attachments prevents people from being able to provide in-line review
	comments.
	</p>

	<p>
	When submitting follow-up patches you can use --in-reply-to to make v2, v3,
	etc patches show up as replies to the originals. This usually works well
	when you're sending out updates to individual patches (as opposed to
	re-sending the whole series). Using --in-reply-to makes
	it harder for reviewers to accidentally review old patches.
	</p>

	<p>
	When submitting follow-up patches you should also login to
	<a href="https://patchwork.freedesktop.org">patchwork</a> and change the
	state of your old patches to Superseded.
	</p>

	<h2 id="reviewing">Reviewing Patches</h2>

	<p>
	When you've reviewed a patch on the mailing list, please be unambiguous
	about your review. That is, state either
	</p>
	<pre>
	Reviewed-by: Joe Hacker <jhacker@foo.com>
	</pre>
	or
	<pre>
	Acked-by: Joe Hacker <jhacker@foo.com>
	</pre>
	<p>
	Rather than saying just "LGTM" or "Seems OK".
	</p>

	<p>
	If small changes are suggested, it's OK to say something like:
	</p>
	<pre>
	With the above fixes, Reviewed-by: Joe Hacker <jhacker@foo.com>
	</pre>
	<p>
	which tells the patch author that the patch can be committed, as long
	as the issues are resolved first.
	</p>


	<h2 id="nominations">Nominating a commit for a stable branch</h2>

	<p>
	There are three ways to nominate patch for inclusion of the stable branch and
	release.
	</p>
	<ul>
	<li> By adding the Cc: mesa-stable@ tag as described below.
	<li> Sending the commit ID (as seen in master branch) to the mesa-stable@ mailing list.
	<li> Forwarding the patch from the mesa-dev@ mailing list.
	</li>
	</ul>
	<p>
	Note: resending patch identical to one on mesa-dev@ or one that differs only
	by the extra mesa-stable@ tag is <strong>not</strong> recommended.
	</p>


	<h3 id="thetag">The stable tag</h3>

	<p>
	If you want a commit to be applied to a stable branch,
	you should add an appropriate note to the commit message.
	</p>

	<p>
	Here are some examples of such a note:
	</p>
	<ul>
	<li>CC: <mesa-stable@lists.freedesktop.org></li>
	<li>CC: "9.2 10.0" <mesa-stable@lists.freedesktop.org></li>
	<li>CC: "10.0" <mesa-stable@lists.freedesktop.org></li>
	</ul>

	Simply adding the CC to the mesa-stable list address is adequate to nominate
	the commit for the most-recently-created stable branch. It is only necessary
	to specify a specific branch name, (such as "9.2 10.0" or "10.0" in the
	examples above), if you want to nominate the commit for an older stable
	branch. And, as in these examples, you can nominate the commit for the older
	branch in addition to the more recent branch, or nominate the commit
	exclusively for the older branch.

	This "CC" syntax for patch nomination will cause patches to automatically be
	copied to the mesa-stable@ mailing list when you use "git send-email" to send
	patches to the mesa-dev@ mailing list. If you prefer using --suppress-cc that
	won't have any effect negative effect on the patch nomination.

	<p>
	Note: by removing the tag [as the commit is pushed] the patch is
	<strong>explicitly</strong> rejected from inclusion in the stable branch(es).
	<br>
	Thus, drop the line <strong>only</strong> if you want to cancel the nomination.
	</p>

	<h2 id="criteria">Criteria for accepting patches to the stable branch</h2>

	Mesa has a designated release manager for each stable branch, and the release
	manager is the only developer that should be pushing changes to these
	branches. Everyone else should simply nominate patches using the mechanism
	described above.

	The stable-release manager will work with the list of nominated patches, and
	for each patch that meets the criteria below will cherry-pick the patch with:
	<code>git cherry-pick -x <commit></code>. The <code>-x</code> option is
	important so that the picked patch references the commit ID of the original
	patch.

	The stable-release manager may at times need to force-push changes to the
	stable branches, for example, to drop a previously-picked patch that was later
	identified as causing a regression). These force-pushes may cause changes to
	be lost from the stable branch if developers push things directly. Consider
	yourself warned.

	The stable-release manager is also given broad discretion in rejecting patches
	that have been nominated for the stable branch. The most basic rule is that
	the stable branch is for bug fixes only, (no new features, no
	regressions). Here is a non-exhaustive list of some reasons that a patch may
	be rejected:

	<ul>
	<li>Patch introduces a regression. Any reported build breakage or other
	regression caused by a particular patch, (game no longer work, piglit test
	changes from PASS to FAIL), is justification for rejecting a patch.</li>

	<li>Patch is too large, (say, larger than 100 lines)</li>

	<li>Patch is not a fix. For example, a commit that moves code around with no
	functional change should be rejected.</li>

	<li>Patch fix is not clearly described. For example, a commit message
	of only a single line, no description of the bug, no mention of bugzilla,
	etc.</li>

	<li>Patch has not obviously been reviewed, For example, the commit message
	has no Reviewed-by, Signed-off-by, nor Tested-by tags from anyone but the
	author.</li>

	<li>Patch has not already been merged to the master branch. As a rule, bug
	fixes should never be applied first to a stable branch. Patches should land
	first on the master branch and then be cherry-picked to a stable
	branch. (This is to avoid future releases causing regressions if the patch
	is not also applied to master.) The only things that might look like
	exceptions would be backports of patches from master that happen to look
	significantly different.</li>

	<li>Patch depends on too many other patches. Ideally, all stable-branch
	patches should be self-contained. It sometimes occurs that a single, logical
	bug-fix occurs as two separate patches on master, (such as an original
	patch, then a subsequent fix-up to that patch). In such a case, these two
	patches should be squashed into a single, self-contained patch for the
	stable branch. (Of course, if the squashing makes the patch too large, then
	that could be a reason to reject the patch.)</li>

	<li>Patch includes new feature development, not bug fixes. New OpenGL
	features, extensions, etc. should be applied to Mesa master and included in
	the next major release. Stable releases are intended only for bug fixes.

	Note: As an exception to this rule, the stable-release manager may accept
	hardware-enabling "features". For example, backports of new code to support
	a newly-developed hardware product can be accepted if they can be reasonably
	determined to not have effects on other hardware.</li>

	<li>Patch is a performance optimization. As a rule, performance patches are
	not candidates for the stable branch. The only exception might be a case
	where an application's performance was recently severely impacted so as to
	become unusable. The fix for this performance regression could then be
	considered for a stable branch. The optimization must also be
	non-controversial and the patches still need to meet the other criteria of
	being simple and self-contained</li>

	<li>Patch introduces a new failure mode (such as an assert). While the new
	assert might technically be correct, for example to make Mesa more
	conformant, this is not the kind of "bug fix" we want in a stable
	release. The potential problem here is that an OpenGL program that was
	previously working, (even if technically non-compliant with the
	specification), could stop working after this patch. So that would be a
	regression that is unacceptable for the stable branch.</li>
	</ul>

	<h2 id="gittips">Git tips</h2>

	<ul>
	<li><code>git rebase -i ...</code> is your friend. Don't be afraid to use it.
	<li>Apply a fixup to commit FOO.
	<pre>
	git add ...
	git commit --fixup=FOO
	git rebase -i --autosquash ...
	</pre>
	<li>Test for build breakage between patches e.g last 8 commits.
	<pre>
	git rebase -i --exec="make -j4" HEAD~8
	</pre>
	<li>Sets the default mailing address for your repo.
	<pre>
	git config --local sendemail.to mesa-dev@lists.freedesktop.org
	</pre>
	<li> Add version to subject line of patch series in this case for the last 8
	commits before sending.
	<pre>
	git send-email --subject-prefix="PATCH v4" HEAD~8
	git send-email -v4 @~8 # shorter version, inherited from git format-patch
	</pre>
	<li> Configure git to use the get_reviewer.pl script interactively. Thus you
	can avoid adding the world to the CC list.
	<pre>
	git config sendemail.cccmd "./scripts/get_reviewer.pl -i"
	</pre>
	</ul>


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