Re: [Kernel-packages] [Bug 1917138] Re: Bionic kernel 4.15.0-136 causes dosemu2 (with kvm mode) freezes due to lack of KVM patch
Dear Guilherme,
I just want to inform you . Today my kernel is upgraded to
version 4.15.0-139-generic, but the bug is still there.
Thank you.
On Fri, Mar 5, 2021 at 4:50 PM Stefan Bader <1917...@bugs.launchpad.net>
wrote:
> ** Changed in: linux (Ubuntu Bionic)
>Status: In Progress => Fix Committed
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1917138
>
> Title:
> Bionic kernel 4.15.0-136 causes dosemu2 (with kvm mode) freezes due to
> lack of KVM patch
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions
>
--
Bambang P
http://bpranoto.blogspot.com
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https://bugs.launchpad.net/bugs/1917138
Title:
Bionic kernel 4.15.0-136 causes dosemu2 (with kvm mode) freezes due to
lack of KVM patch
Status in Dosemu2:
New
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Bionic:
Fix Committed
Bug description:
[Impact]
* Since kernel 4.15.0-136, Bionic kernel included a very complex KVM fix for
a kind of "race" in interrupt window with irqchip-split (reported in [0]). The
fix was proposed in the form of a patch series containing 2 patches [1] - this
was merged in Ubuntu though the stable tree, in the form of the following
commit:
71cc849b7093 ("KVM: x86: Fix split-irqchip vs interrupt injection window
request") [2]
* The problem is that such commit has a companion required commit,
which was not proposed in the stable tree. In fact, there was a
confusion among KVM community and the stable maintainer [3], due to
the lack of such missing commit - because of that, the series was
removed from stable trees 4.14.y and 4.9.y, but the solo commit was
merged alone in Ubuntu kernel.
* Without the companion patch, we might have a KVM infinite "loop" condition
in the core IRQ handling, since the merged commit requires an extra check in
kvm_cpu_has_extint() and a condition "inversion" in kvm_cpu_get_extint(), only
present in the missing companion patch. Users reported that this manifested as
dosemu2 (running in KVM mode) to be stuck in kernel 4.15.0-136 and -137, while
works fine in 4.15.0-135 and the
-137 plus the companion patch.
* So, we hereby backport the companion commit, originally upstream
patch: 72c3bcdcda ("KVM: x86: handle !lapic_in_kernel case in
kvm_cpu_*_extint") [4]
[Test Case]
* The test case proposed was the reported bug: try running dosemu2 (with kvm
mode enabled) and it fails without the companion commit.
* In order to test the correctness of both fixes together, we could
rely in the test proposed in [0] (running a guest with "noapic"), but
it wasn't consistent and the VMM wasn't mentioned, so we might have a
workaround mechanism in qemu, for example, preventing such test to
reproduce the issue.
[Where problems could occur]
* Since this is a KVM core modification, it could affect interrupt handling
in KVM but without the fix, we are already experiencing a bug. Also, both
commits were backported to 5.4.y and 4.19.y, so Focal and subsequent released
are already running with them.
[0]
https://lore.kernel.org/kvm/62918f65ec78f8990278a6a0db0567968fa23e49.ca...@infradead.org/
[1]
https://lore.kernel.org/kvm/20201127112114.3219360-1-pbonz...@redhat.com/
[2] http://git.kernel.org/linus/71cc849b70
[3]
https://lore.kernel.org/stable/d29c4b25-33f6-8d99-7a45-8f4e06f5a...@redhat.com/
[4] http://git.kernel.org/linus/72c3bcdcda
With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu
16.04, dosemu2 with kvm freezes boot.
dosemu2 source: https://github.com/dosemu2/dosemu2
dosemu2 package can be obtained from
https://launchpad.net/~dosemu2/+archive/ubuntu/ppa
1. ubuntu version
lsb_release -rd
Description: Ubuntu 18.04.5 LTS
Release: 18.04
2. package version
$ apt-cache policy dosemu2
dosemu2:
Installed: (none)
Candidate: (none)
Version table:
2.0~pre8-2 -1
100 /var/lib/dpkg/status
3. What is expected to happen: The dosemu program runs fine as in previous
kernel version
4. What happened instead: The dosemu freezes on loading
I have also reported this problem to dosemu2 developer, here is my bug report:
https://github.com/dosemu2/dosemu2/issues/1404
To manage notifications about this bug go to:
https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions
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[Kernel-packages] [Bug 1917138] Re: Bionic kernel 4.15.0-136 causes dosemu2 (with kvm mode) freezes due to lack of KVM patch
** Tags removed: bot-comment verification-needed-bionic
** Tags added: verification-done-bionic
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1917138
Title:
Bionic kernel 4.15.0-136 causes dosemu2 (with kvm mode) freezes due to
lack of KVM patch
Status in Dosemu2:
New
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Bionic:
Fix Committed
Bug description:
[Impact]
* Since kernel 4.15.0-136, Bionic kernel included a very complex KVM fix for
a kind of "race" in interrupt window with irqchip-split (reported in [0]). The
fix was proposed in the form of a patch series containing 2 patches [1] - this
was merged in Ubuntu though the stable tree, in the form of the following
commit:
71cc849b7093 ("KVM: x86: Fix split-irqchip vs interrupt injection window
request") [2]
* The problem is that such commit has a companion required commit,
which was not proposed in the stable tree. In fact, there was a
confusion among KVM community and the stable maintainer [3], due to
the lack of such missing commit - because of that, the series was
removed from stable trees 4.14.y and 4.9.y, but the solo commit was
merged alone in Ubuntu kernel.
* Without the companion patch, we might have a KVM infinite "loop" condition
in the core IRQ handling, since the merged commit requires an extra check in
kvm_cpu_has_extint() and a condition "inversion" in kvm_cpu_get_extint(), only
present in the missing companion patch. Users reported that this manifested as
dosemu2 (running in KVM mode) to be stuck in kernel 4.15.0-136 and -137, while
works fine in 4.15.0-135 and the
-137 plus the companion patch.
* So, we hereby backport the companion commit, originally upstream
patch: 72c3bcdcda ("KVM: x86: handle !lapic_in_kernel case in
kvm_cpu_*_extint") [4]
[Test Case]
* The test case proposed was the reported bug: try running dosemu2 (with kvm
mode enabled) and it fails without the companion commit.
* In order to test the correctness of both fixes together, we could
rely in the test proposed in [0] (running a guest with "noapic"), but
it wasn't consistent and the VMM wasn't mentioned, so we might have a
workaround mechanism in qemu, for example, preventing such test to
reproduce the issue.
[Where problems could occur]
* Since this is a KVM core modification, it could affect interrupt handling
in KVM but without the fix, we are already experiencing a bug. Also, both
commits were backported to 5.4.y and 4.19.y, so Focal and subsequent released
are already running with them.
[0]
https://lore.kernel.org/kvm/62918f65ec78f8990278a6a0db0567968fa23e49.ca...@infradead.org/
[1]
https://lore.kernel.org/kvm/20201127112114.3219360-1-pbonz...@redhat.com/
[2] http://git.kernel.org/linus/71cc849b70
[3]
https://lore.kernel.org/stable/d29c4b25-33f6-8d99-7a45-8f4e06f5a...@redhat.com/
[4] http://git.kernel.org/linus/72c3bcdcda
With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu
16.04, dosemu2 with kvm freezes boot.
dosemu2 source: https://github.com/dosemu2/dosemu2
dosemu2 package can be obtained from
https://launchpad.net/~dosemu2/+archive/ubuntu/ppa
1. ubuntu version
lsb_release -rd
Description: Ubuntu 18.04.5 LTS
Release: 18.04
2. package version
$ apt-cache policy dosemu2
dosemu2:
Installed: (none)
Candidate: (none)
Version table:
2.0~pre8-2 -1
100 /var/lib/dpkg/status
3. What is expected to happen: The dosemu program runs fine as in previous
kernel version
4. What happened instead: The dosemu freezes on loading
I have also reported this problem to dosemu2 developer, here is my bug report:
https://github.com/dosemu2/dosemu2/issues/1404
To manage notifications about this bug go to:
https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions
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Re: [Kernel-packages] [Bug 1917138] Re: kernel 4.15.0-136 causes dosemu2 with kvm freezes
Dear Guilherme, Thank you very much for your reply. On Tue, Mar 2, 2021 at 3:00 AM Guilherme G. Piccoli < 1917...@bugs.launchpad.net> wrote: > Thanks for the report! Are you using nested virtualization (a virtual > machine inside another virtual machine) or you run dosbox directly in your > host/bare-metal system? > > I run it directly on the real hardware/bare-metal system. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1917138 Title: kernel 4.15.0-136 causes dosemu2 with kvm freezes Status in Dosemu2: New Status in linux package in Ubuntu: Confirmed Bug description: With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu 16.04, dosemu2 with kvm freezes boot. dosemu2 source: https://github.com/dosemu2/dosemu2 dosemu2 package can be obtained from https://launchpad.net/~dosemu2/+archive/ubuntu/ppa 1. ubuntu version lsb_release -rd Description: Ubuntu 18.04.5 LTS Release: 18.04 2. package version $ apt-cache policy dosemu2 dosemu2: Installed: (none) Candidate: (none) Version table: 2.0~pre8-2 -1 100 /var/lib/dpkg/status 3. What is expected to happen: The dosemu program runs fine as in previous kernel version 4. What happened instead: The dosemu freezes on loading I have also reported this problem to dosemu2 developer, here is my bug report: https://github.com/dosemu2/dosemu2/issues/1404 To manage notifications about this bug go to: https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
Re: [Kernel-packages] [Bug 1917138] Re: kernel 4.15.0-136 causes dosemu2 with kvm freezes
Dear Guilherme, I will try and come back to you later. Thanks again. On Tue, Mar 2, 2021 at 4:56 AM Guilherme G. Piccoli < 1917...@bugs.launchpad.net> wrote: > Thanks again Bambang and Hans-Christian for the report, it seems indeed > a bug in the kernel. I think I know what's going on, but I'd like to ask > you to perform some testing in order we can prove that, and then fix it. > > So, first it'll be 2 tests - depending on the result, a third test will be > necessary. > Please be sure to try both (1) and (2) with dos2emu using the KVM mode: > > (1) For the first test, please get the Bionic proposed kernel (see [0] > for information on how to do it) - the current proposed version is > 4.15.0-137. Try to reproduce with that version - I expect it to > reproduce. > > (2) Now, get the build I made for you in > https://kernel.ubuntu.com/~gpiccoli/lp1917138/ - observe that if you have > the "linux-modules-extra" and "linux-headers" already installed on your > system after test (1), please also install them from my build or else you > might have issues in the boot process. To install the packages, download > them from the link above to some directory and then run "dpkg -i *.deb" > (supposing no other .deb file is present in that directory). > Reboot the system after a successful installation and try to reproduce the > issue - I suspect it won't reproduce, dosemu2 should work fine even in KVM > mode. > > Thanks in advance, > > > Guilherme > > > [0] https://wiki.ubuntu.com/Testing/EnableProposed > (don't forget to disable the proposed repository after your tests) > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1917138 > > Title: > kernel 4.15.0-136 causes dosemu2 with kvm freezes > > To manage notifications about this bug go to: > https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions > -- Bambang P http://bpranoto.blogspot.com -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1917138 Title: kernel 4.15.0-136 causes dosemu2 with kvm freezes Status in Dosemu2: New Status in linux package in Ubuntu: Confirmed Bug description: With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu 16.04, dosemu2 with kvm freezes boot. dosemu2 source: https://github.com/dosemu2/dosemu2 dosemu2 package can be obtained from https://launchpad.net/~dosemu2/+archive/ubuntu/ppa 1. ubuntu version lsb_release -rd Description: Ubuntu 18.04.5 LTS Release: 18.04 2. package version $ apt-cache policy dosemu2 dosemu2: Installed: (none) Candidate: (none) Version table: 2.0~pre8-2 -1 100 /var/lib/dpkg/status 3. What is expected to happen: The dosemu program runs fine as in previous kernel version 4. What happened instead: The dosemu freezes on loading I have also reported this problem to dosemu2 developer, here is my bug report: https://github.com/dosemu2/dosemu2/issues/1404 To manage notifications about this bug go to: https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
Re: [Kernel-packages] [Bug 1917138] Re: kernel 4.15.0-136 causes dosemu2 with kvm freezes
Hello Guilherme, Yes you are right. The 137 from the Pre-released update doesn't work. The 137 files from https://kernel.ubuntu.com/~gpiccoli/lp1917138/ works perfectly. Thank you very much! Out of curiosity, what went wrong with the 136? On Tue, Mar 2, 2021 at 7:20 PM Guilherme G. Piccoli < 1917...@bugs.launchpad.net> wrote: > Thanks Bambang, let me know as soon as possible, so we can maybe fix > this cycle (worst case, next cycle). > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1917138 > > Title: > kernel 4.15.0-136 causes dosemu2 with kvm freezes > > To manage notifications about this bug go to: > https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions > -- Bambang P http://bpranoto.blogspot.com -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1917138 Title: kernel 4.15.0-136 causes dosemu2 with kvm freezes Status in Dosemu2: New Status in linux package in Ubuntu: Confirmed Bug description: With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu 16.04, dosemu2 with kvm freezes boot. dosemu2 source: https://github.com/dosemu2/dosemu2 dosemu2 package can be obtained from https://launchpad.net/~dosemu2/+archive/ubuntu/ppa 1. ubuntu version lsb_release -rd Description: Ubuntu 18.04.5 LTS Release: 18.04 2. package version $ apt-cache policy dosemu2 dosemu2: Installed: (none) Candidate: (none) Version table: 2.0~pre8-2 -1 100 /var/lib/dpkg/status 3. What is expected to happen: The dosemu program runs fine as in previous kernel version 4. What happened instead: The dosemu freezes on loading I have also reported this problem to dosemu2 developer, here is my bug report: https://github.com/dosemu2/dosemu2/issues/1404 To manage notifications about this bug go to: https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
Re: [Kernel-packages] [Bug 1917138] Re: kernel 4.15.0-136 causes dosemu2 with kvm freezes
Dear Guilherme, On Wed, Mar 3, 2021 at 1:45 AM Guilherme G. Piccoli < 1917...@bugs.launchpad.net> wrote: > So Bambang and/or Hans-Christian, can you please test the following > kernel build that includes the aforementioned missing commit: > > https://kernel.ubuntu.com/~gpiccoli/lp1917138-2/ > > Yes, it works very well. Thank you very much! -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1917138 Title: kernel 4.15.0-136 causes dosemu2 with kvm freezes Status in Dosemu2: Fix Released Status in linux package in Ubuntu: In Progress Bug description: With the latest kernel 4.15.0-136 updates on ubuntu 18.04 and ubuntu 16.04, dosemu2 with kvm freezes boot. dosemu2 source: https://github.com/dosemu2/dosemu2 dosemu2 package can be obtained from https://launchpad.net/~dosemu2/+archive/ubuntu/ppa 1. ubuntu version lsb_release -rd Description: Ubuntu 18.04.5 LTS Release: 18.04 2. package version $ apt-cache policy dosemu2 dosemu2: Installed: (none) Candidate: (none) Version table: 2.0~pre8-2 -1 100 /var/lib/dpkg/status 3. What is expected to happen: The dosemu program runs fine as in previous kernel version 4. What happened instead: The dosemu freezes on loading I have also reported this problem to dosemu2 developer, here is my bug report: https://github.com/dosemu2/dosemu2/issues/1404 To manage notifications about this bug go to: https://bugs.launchpad.net/dosemu2/+bug/1917138/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
