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From: Ian Campbell <ian.campbell@citrix.com>
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: keir@xen.org, xen-devel@lists.xensource.com,
	ian.jackson@eu.citrix.com, stefano.stabellini@eu.citrix.com
Subject: Re: [linux-3.18 bisection] complete test-amd64-amd64-xl-pvh-intel
Date: Thu, 9 Jul 2015 14:55:52 +0100	[thread overview]
Message-ID: <1436450152.23508.134.camel@citrix.com> (raw)
In-Reply-To: <E1ZDBso-0008Rm-Vt@osstest.test-lab.xenproject.org>

Boris has already requested the backport of the incremental fix to this
change.

Ian.

On Thu, 2015-07-09 at 13:28 +0000, osstest service owner wrote:
> branch xen-unstable
> xen branch xen-unstable
> job test-amd64-amd64-xl-pvh-intel
> test guest-start
> 
> Tree: linux git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> Tree: linuxfirmware git://xenbits.xen.org/osstest/linux-firmware.git
> Tree: qemu git://xenbits.xen.org/staging/qemu-xen-unstable.git
> Tree: qemuu git://xenbits.xen.org/staging/qemu-upstream-unstable.git
> Tree: xen git://xenbits.xen.org/xen.git
> 
> *** Found and reproduced problem changeset ***
> 
>   Bug is in tree:  linux git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
>   Bug introduced:  63753fac67e11fb6bac3d5c6a48bd319d9e612c2
>   Bug not present: 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29
> 
> 
>   commit 63753fac67e11fb6bac3d5c6a48bd319d9e612c2
>   Author: Andy Lutomirski <luto@amacapital.net>
>   Date:   Fri Oct 24 15:58:08 2014 -0700
>   
>       x86: Store a per-cpu shadow copy of CR4
>       
>       [ Upstream commit 1e02ce4cccdcb9688386e5b8d2c9fa4660b45389 ]
>       
>       Context switches and TLB flushes can change individual bits of CR4.
>       CR4 reads take several cycles, so store a shadow copy of CR4 in a
>       per-cpu variable.
>       
>       To avoid wasting a cache line, I added the CR4 shadow to
>       cpu_tlbstate, which is already touched in switch_mm.  The heaviest
>       users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
>       __switch_to_xtra is called shortly after switch_mm during context
>       switch, so the cacheline is likely to be hot.
>       
>       Signed-off-by: Andy Lutomirski <luto@amacapital.net>
>       Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
>       Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>       Cc: Kees Cook <keescook@chromium.org>
>       Cc: Andrea Arcangeli <aarcange@redhat.com>
>       Cc: Vince Weaver <vince@deater.net>
>       Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
>       Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
>       Cc: Paul Mackerras <paulus@samba.org>
>       Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
>       Cc: Linus Torvalds <torvalds@linux-foundation.org>
>       Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
>       Signed-off-by: Ingo Molnar <mingo@kernel.org>
>       Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
> 
> 
> For bisection revision-tuple graph see:
>    http://logs.test-lab.xenproject.org/osstest/results/bisect/linux-3.18/test-amd64-amd64-xl-pvh-intel.guest-start.html
> Revision IDs in each graph node refer, respectively, to the Trees above.
> 
> ----------------------------------------
> Searching for failure / basis pass:
>  59177 fail [host=huxelrebe0] / 58558 ok.
> Failure / basis pass flights: 59177 / 58558
> (tree with no url: ovmf)
> (tree with no url: seabios)
> Tree: linux git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> Tree: linuxfirmware git://xenbits.xen.org/osstest/linux-firmware.git
> Tree: qemu git://xenbits.xen.org/staging/qemu-xen-unstable.git
> Tree: qemuu git://xenbits.xen.org/staging/qemu-upstream-unstable.git
> Tree: xen git://xenbits.xen.org/xen.git
> Latest ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
> Basis pass d048c068d00da7d4cfa5ea7651933b99026958cf c530a75c1e6a472b0eb9558310b518f0dfcd8860 38609ae72b0a9e09b42be94f469fef928a1049fa 579e90432e995d6cb6f8520aca557fa6646f94ec 12e817e281034f5881f46e0e4f1d127820101a78
> Generating revisions with ./adhoc-revtuple-generator  git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git#d048c068d00da7d4cfa5ea7651933b99026958cf-ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 git://xenbits.xen.org/osstest/linux-firmware.git#c530a75c1e6a472b0eb9558310b518f0dfcd8860-c530a75c1e6a472b0eb9558310b518f0dfcd8860 git://xenbits.xen.org/staging/qemu-xen-unstable.git#38609ae72b0a9e09b42be94f469fef928a1049fa-3e2e51ecc1120bd59537ed19b6bc7066511c7e2e git://xenbits.xen.org/staging/qemu-upstream-unstable.git#579e90432e995d6cb6f8520aca557fa6646f94ec-c4a962ec0c61aa9b860a3635c8424472e6c2cc2c git://xenbits.xen.org/xen.git#12e817e281034f5881f46e0e4f1d127820101a78-c40317f11b3f05e7c06a2213560c8471081f2662
> + exec
> + sh -xe
> + cd /home/osstest/repos/linux-stable
> + git remote set-url origin git://cache:9419/git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/qemu-xen-unstable
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/staging/qemu-xen-unstable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/qemu-upstream-unstable
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/staging/qemu-upstream-unstable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/xen
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/xen.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/linux-stable
> + git remote set-url origin git://cache:9419/git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/qemu-xen-unstable
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/staging/qemu-xen-unstable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/qemu-upstream-unstable
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/staging/qemu-upstream-unstable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> + exec
> + sh -xe
> + cd /home/osstest/repos/xen
> + git remote set-url origin git://cache:9419/git://xenbits.xen.org/xen.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> Loaded 13308 nodes in revision graph
> Searching for test results:
>  58558 pass d048c068d00da7d4cfa5ea7651933b99026958cf c530a75c1e6a472b0eb9558310b518f0dfcd8860 38609ae72b0a9e09b42be94f469fef928a1049fa 579e90432e995d6cb6f8520aca557fa6646f94ec 12e817e281034f5881f46e0e4f1d127820101a78
>  58987 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  58976 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59001 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59027 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59015 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59041 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59075 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59050 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59171 pass 90b934b19c15a1f1a8140e93af719cb741e4cf40 c530a75c1e6a472b0eb9558310b518f0dfcd8860 38609ae72b0a9e09b42be94f469fef928a1049fa 579e90432e995d6cb6f8520aca557fa6646f94ec b58214a24231a1f2a7e09ae9cc3014eff752918b
>  59176 pass e7bc7f46a93328ef222eb39c4bd645fa028e7c57 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59116 pass d048c068d00da7d4cfa5ea7651933b99026958cf c530a75c1e6a472b0eb9558310b518f0dfcd8860 38609ae72b0a9e09b42be94f469fef928a1049fa 579e90432e995d6cb6f8520aca557fa6646f94ec 12e817e281034f5881f46e0e4f1d127820101a78
>  59178 pass 97cd3676ab52cc5943a19af63c6698639d532b8a c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59157 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59117 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59165 pass 90b934b19c15a1f1a8140e93af719cb741e4cf40 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c 5f33fa2bca6354fad1decfeda723c046311e85cc
>  59175 pass 90b934b19c15a1f1a8140e93af719cb741e4cf40 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c 005bc3b588e3e1bd07a97fd752ab17042c41f21b
>  59177 fail ea5dd38e93b3bec3427e5d3eef000bbf5d637e76 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59208 pass ccf63e05bb863b7cc821fb4e1429f0a4e7ed1686 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59211 pass 4621614dd5115749c2b04c80f0f53861cd93590e c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59215 fail 63753fac67e11fb6bac3d5c6a48bd319d9e612c2 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59218 pass 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59225 fail 63753fac67e11fb6bac3d5c6a48bd319d9e612c2 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59284 fail 63753fac67e11fb6bac3d5c6a48bd319d9e612c2 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59282 pass 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59292 fail 63753fac67e11fb6bac3d5c6a48bd319d9e612c2 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
>  59287 pass 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
> Searching for interesting versions
>  Result found: flight 58558 (pass), for basis pass
>  Result found: flight 58976 (fail), for basis failure
>  Repro found: flight 59116 (pass), for basis pass
>  Repro found: flight 59117 (fail), for basis failure
>  0 revisions at 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29 c530a75c1e6a472b0eb9558310b518f0dfcd8860 3e2e51ecc1120bd59537ed19b6bc7066511c7e2e c4a962ec0c61aa9b860a3635c8424472e6c2cc2c c40317f11b3f05e7c06a2213560c8471081f2662
> No revisions left to test, checking graph state.
>  Result found: flight 59218 (pass), for last pass
>  Result found: flight 59225 (fail), for first failure
>  Repro found: flight 59282 (pass), for last pass
>  Repro found: flight 59284 (fail), for first failure
>  Repro found: flight 59287 (pass), for last pass
>  Repro found: flight 59292 (fail), for first failure
> 
> *** Found and reproduced problem changeset ***
> 
>   Bug is in tree:  linux git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
>   Bug introduced:  63753fac67e11fb6bac3d5c6a48bd319d9e612c2
>   Bug not present: 8ca6fadf220ab0a1369a667462d8d8c0c5d6ac29
> 
> + exec
> + sh -xe
> + cd /home/osstest/repos/linux-stable
> + git remote set-url origin git://cache:9419/git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> + git fetch -p origin +refs/heads/*:refs/remotes/origin/*
> 
>   commit 63753fac67e11fb6bac3d5c6a48bd319d9e612c2
>   Author: Andy Lutomirski <luto@amacapital.net>
>   Date:   Fri Oct 24 15:58:08 2014 -0700
>   
>       x86: Store a per-cpu shadow copy of CR4
>       
>       [ Upstream commit 1e02ce4cccdcb9688386e5b8d2c9fa4660b45389 ]
>       
>       Context switches and TLB flushes can change individual bits of CR4.
>       CR4 reads take several cycles, so store a shadow copy of CR4 in a
>       per-cpu variable.
>       
>       To avoid wasting a cache line, I added the CR4 shadow to
>       cpu_tlbstate, which is already touched in switch_mm.  The heaviest
>       users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
>       __switch_to_xtra is called shortly after switch_mm during context
>       switch, so the cacheline is likely to be hot.
>       
>       Signed-off-by: Andy Lutomirski <luto@amacapital.net>
>       Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
>       Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>       Cc: Kees Cook <keescook@chromium.org>
>       Cc: Andrea Arcangeli <aarcange@redhat.com>
>       Cc: Vince Weaver <vince@deater.net>
>       Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
>       Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
>       Cc: Paul Mackerras <paulus@samba.org>
>       Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
>       Cc: Linus Torvalds <torvalds@linux-foundation.org>
>       Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
>       Signed-off-by: Ingo Molnar <mingo@kernel.org>
>       Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
> 
> pnmtopng: 248 colors found
> Revision graph left in /home/logs/results/bisect/linux-3.18/test-amd64-amd64-xl-pvh-intel.guest-start.{dot,ps,png,html}.
> ----------------------------------------
> 59292: tolerable ALL FAIL
> 
> flight 59292 linux-3.18 real-bisect [real]
> http://logs.test-lab.xenproject.org/osstest/logs/59292/
> 
> Failures :-/ but no regressions.
> 
> Tests which did not succeed,
> including tests which could not be run:
>  test-amd64-amd64-xl-pvh-intel 11 guest-start            fail baseline untested
> 
> 
> jobs:
>  test-amd64-amd64-xl-pvh-intel                                fail    
> 
> 
> ------------------------------------------------------------
> sg-report-flight on osstest.test-lab.xenproject.org
> logs: /home/logs/logs
> images: /home/logs/images
> 
> Logs, config files, etc. are available at
>     http://logs.test-lab.xenproject.org/osstest/logs
> 
> Explanation of these reports, and of osstest in general, is at
>     http://xenbits.xen.org/gitweb/?p=osstest.git;a=blob;f=README.email;hb=master
>     http://xenbits.xen.org/gitweb/?p=osstest.git;a=blob;f=README;hb=master
> 
> Test harness code can be found at
>     http://xenbits.xen.org/gitweb?p=osstest.git;a=summary
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel

  reply	other threads:[~2015-07-09 13:55 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-09 13:28 [linux-3.18 bisection] complete test-amd64-amd64-xl-pvh-intel osstest service owner
2015-07-09 13:55 ` Ian Campbell [this message]
  -- strict thread matches above, loose matches on Subject: below --
2015-09-10  8:34 osstest service owner
2017-10-11  4:54 osstest service owner
2017-10-11  7:35 ` Roger Pau Monné

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