| Message ID | 20220617073630.535914-2-chen.zhang@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce QEMU userspace ebpf support | expand |
On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > Make iovisor/ubpf project be a git submodule for QEMU. > It will auto clone ubpf project when configure QEMU. I don't think we need todo this. As it is brand new functionality we don't have any back compat issues. We should just expect the distros to ship ubpf if they want their QEMU builds to take advantage of it. With regards, Daniel
> -----Original Message----- > From: Daniel P. Berrangé <berrange@redhat.com> > Sent: Friday, June 17, 2022 4:05 PM > To: Zhang, Chen <chen.zhang@intel.com> > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus > Armbruster <armbru@redhat.com>; Peter Maydell > <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; Laurent > Vivier <lvivier@redhat.com>; Yuri Benditovich > <yuri.benditovich@daynix.com>; Andrew Melnychenko > <andrew@daynix.com> > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > submodule for QEMU > > On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > Make iovisor/ubpf project be a git submodule for QEMU. > > It will auto clone ubpf project when configure QEMU. > > I don't think we need todo this. As it is brand new functionality we don't have > any back compat issues. We should just expect the distros to ship ubpf if > they want their QEMU builds to take advantage of it. > Yes, agree. It's the best way to use the uBPF project. But current status is distros(ubuntu, RHEL...) does not ship the iovisor/ubpf like the iovisor/bcc. So I have to do it. Or do you have any better suggestions? Thanks Chen > > With regards, > Daniel > -- > |: https://berrange.com -o- > https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- > https://www.instagram.com/dberrange :|
On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > > > > -----Original Message----- > > From: Daniel P. Berrangé <berrange@redhat.com> > > Sent: Friday, June 17, 2022 4:05 PM > > To: Zhang, Chen <chen.zhang@intel.com> > > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus > > Armbruster <armbru@redhat.com>; Peter Maydell > > <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; Laurent > > Vivier <lvivier@redhat.com>; Yuri Benditovich > > <yuri.benditovich@daynix.com>; Andrew Melnychenko > > <andrew@daynix.com> > > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > > submodule for QEMU > > > > On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > > Make iovisor/ubpf project be a git submodule for QEMU. > > > It will auto clone ubpf project when configure QEMU. > > > > I don't think we need todo this. As it is brand new functionality we don't have > > any back compat issues. We should just expect the distros to ship ubpf if > > they want their QEMU builds to take advantage of it. > > > > Yes, agree. It's the best way to use the uBPF project. > But current status is distros(ubuntu, RHEL...) does not ship > the iovisor/ubpf like the iovisor/bcc. So I have to do it. > Or do you have any better suggestions? If distros want to support the functionality, they can add packages for it IMHO. With regards, Daniel
On 20/06/2022 10.11, Daniel P. Berrangé wrote: > On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: >> >> >>> -----Original Message----- >>> From: Daniel P. Berrangé <berrange@redhat.com> >>> Sent: Friday, June 17, 2022 4:05 PM >>> To: Zhang, Chen <chen.zhang@intel.com> >>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- >>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo >>> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus >>> Armbruster <armbru@redhat.com>; Peter Maydell >>> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; Laurent >>> Vivier <lvivier@redhat.com>; Yuri Benditovich >>> <yuri.benditovich@daynix.com>; Andrew Melnychenko >>> <andrew@daynix.com> >>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a >>> submodule for QEMU >>> >>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: >>>> Make iovisor/ubpf project be a git submodule for QEMU. >>>> It will auto clone ubpf project when configure QEMU. >>> >>> I don't think we need todo this. As it is brand new functionality we don't have >>> any back compat issues. We should just expect the distros to ship ubpf if >>> they want their QEMU builds to take advantage of it. >>> >> >> Yes, agree. It's the best way to use the uBPF project. >> But current status is distros(ubuntu, RHEL...) does not ship >> the iovisor/ubpf like the iovisor/bcc. So I have to do it. >> Or do you have any better suggestions? > > If distros want to support the functionality, they can add packages for > it IMHO. Yes, let's please avoid new submodules. Submodules can sometimes be a real PITA (e.g. if you forget to update before rsync'ing your code to a machine that has limited internet access), and if users install QEMU from sources, they can also install ubpf from sources, too. And if distros want to support this feature, they can package ubpf on their own, as Daniel said. Thomas
> -----Original Message----- > From: Thomas Huth <thuth@redhat.com> > Sent: Monday, June 20, 2022 4:47 PM > To: Daniel P. Berrangé <berrange@redhat.com>; Zhang, Chen > <chen.zhang@intel.com> > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus > Armbruster <armbru@redhat.com>; Peter Maydell > <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri > Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > <andrew@daynix.com> > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > submodule for QEMU > > On 20/06/2022 10.11, Daniel P. Berrangé wrote: > > On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > >> > >> > >>> -----Original Message----- > >>> From: Daniel P. Berrangé <berrange@redhat.com> > >>> Sent: Friday, June 17, 2022 4:05 PM > >>> To: Zhang, Chen <chen.zhang@intel.com> > >>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > >>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > >>> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > >>> Markus Armbruster <armbru@redhat.com>; Peter Maydell > >>> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; > Laurent > >>> Vivier <lvivier@redhat.com>; Yuri Benditovich > >>> <yuri.benditovich@daynix.com>; Andrew Melnychenko > >>> <andrew@daynix.com> > >>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project > >>> as a submodule for QEMU > >>> > >>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > >>>> Make iovisor/ubpf project be a git submodule for QEMU. > >>>> It will auto clone ubpf project when configure QEMU. > >>> > >>> I don't think we need todo this. As it is brand new functionality we > >>> don't have any back compat issues. We should just expect the distros > >>> to ship ubpf if they want their QEMU builds to take advantage of it. > >>> > >> > >> Yes, agree. It's the best way to use the uBPF project. > >> But current status is distros(ubuntu, RHEL...) does not ship the > >> iovisor/ubpf like the iovisor/bcc. So I have to do it. > >> Or do you have any better suggestions? > > > > If distros want to support the functionality, they can add packages > > for it IMHO. > > Yes, let's please avoid new submodules. Submodules can sometimes be a > real PITA (e.g. if you forget to update before rsync'ing your code to a > machine that has limited internet access), and if users install QEMU from > sources, they can also install ubpf from sources, too. > And if distros want to support this feature, they can package ubpf on their > own, as Daniel said. Hi Daniel and Thomas, I don't know much the background history of QEMU submodules, but meson build is a submodule for QEMU too. It means user can't install QEMU from sources with limited internet access. And back to Daniel's comments, Yes, the best way is distros add the ubpf packages, But maybe it's too late to implement new features for us. We can introduce the submodule now and auto change to the distros's lib when distros add it. For example QEMU's submodule SLIRP do it in the same way. It's already added by most distros and still as a QEMU submodule. It make user experience the latest technology with no other dependencies. uBPF infrastructure have the ability to extend the capabilities without requiring changing source code. If we not allow it, we have to re-implement all the eBPF assembler, disassembler, interpreter, and JIT compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by license issue). Thanks Chen > > Thomas
On 20/06/2022 11.29, Zhang, Chen wrote: > > >> -----Original Message----- >> From: Thomas Huth <thuth@redhat.com> >> Sent: Monday, June 20, 2022 4:47 PM >> To: Daniel P. Berrangé <berrange@redhat.com>; Zhang, Chen >> <chen.zhang@intel.com> >> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- >> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo >> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus >> Armbruster <armbru@redhat.com>; Peter Maydell >> <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri >> Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko >> <andrew@daynix.com> >> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a >> submodule for QEMU >> >> On 20/06/2022 10.11, Daniel P. Berrangé wrote: >>> On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: >>>> >>>> >>>>> -----Original Message----- >>>>> From: Daniel P. Berrangé <berrange@redhat.com> >>>>> Sent: Friday, June 17, 2022 4:05 PM >>>>> To: Zhang, Chen <chen.zhang@intel.com> >>>>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- >>>>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo >>>>> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; >>>>> Markus Armbruster <armbru@redhat.com>; Peter Maydell >>>>> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; >> Laurent >>>>> Vivier <lvivier@redhat.com>; Yuri Benditovich >>>>> <yuri.benditovich@daynix.com>; Andrew Melnychenko >>>>> <andrew@daynix.com> >>>>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project >>>>> as a submodule for QEMU >>>>> >>>>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: >>>>>> Make iovisor/ubpf project be a git submodule for QEMU. >>>>>> It will auto clone ubpf project when configure QEMU. >>>>> >>>>> I don't think we need todo this. As it is brand new functionality we >>>>> don't have any back compat issues. We should just expect the distros >>>>> to ship ubpf if they want their QEMU builds to take advantage of it. >>>>> >>>> >>>> Yes, agree. It's the best way to use the uBPF project. >>>> But current status is distros(ubuntu, RHEL...) does not ship the >>>> iovisor/ubpf like the iovisor/bcc. So I have to do it. >>>> Or do you have any better suggestions? >>> >>> If distros want to support the functionality, they can add packages >>> for it IMHO. >> >> Yes, let's please avoid new submodules. Submodules can sometimes be a >> real PITA (e.g. if you forget to update before rsync'ing your code to a >> machine that has limited internet access), and if users install QEMU from >> sources, they can also install ubpf from sources, too. >> And if distros want to support this feature, they can package ubpf on their >> own, as Daniel said. > > Hi Daniel and Thomas, > > I don't know much the background history of QEMU submodules, but meson build > is a submodule for QEMU too. It means user can't install QEMU from sources > with limited internet access. There is no written policy, but I think the general consensus is that we only ship code in submodules if: 1) It's not available in a required version in distros yet and 2) it is essentially required to build QEMU (like meson) or if the feature has been part of the QEMU sources before and then moved to a separate repository (like slirp). We ship meson as a submodule since we require some meson features that are not available with the meson versions in the distros yet. Once the distros catch up, we'll likely remove the meson submodule from QEMU. > And back to Daniel's comments, Yes, the best way is distros add the ubpf packages, > But maybe it's too late to implement new features for us. We can introduce the submodule now and > auto change to the distros's lib when distros add it. For example QEMU's submodule SLIRP do it in the same way. slirp used to be part of the QEMU repository, but then has been moved to a separate project a while ago. However, at that point in time there weren't any packages ins distros yet, so we had to include it as a submodule. Now that the distros ship it, too, we're planning to remove the slirp submodule from QEMU soon, see: https://lists.gnu.org/archive/html/qemu-devel/2022-04/msg00974.html > It make user experience the latest technology > with no other dependencies. Well, that's only true if we update the submodule in QEMU regularly. If we forget to update, we could easily miss some important (maybe even security related) fixes from the upstream projects. This can be a nightmare for distros, when they then have to go around and look into each and every projects whether they embed a certain code module that needs a CVE fix. It's better if it can be fixed in one central spot instead. > uBPF infrastructure have the ability to extend the capabilities without requiring > changing source code. If we not allow it, we have to re-implement all the eBPF assembler, disassembler, > interpreter, and JIT compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by license issue). Not sure whether I understood that statement right ... nobody said that QEMU should not allow it - we just suggested to rely on a system installation of ubpf instead of embedding the code. Or is that not possible?? (I don't know that project yet - isn't it possible to compile it as a shared library?) Thomas
On Mon, Jun 20, 2022 at 09:29:05AM +0000, Zhang, Chen wrote: > > > > > On 20/06/2022 10.11, Daniel P. Berrangé wrote: > > > On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > > >> > > >> > > >>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > >>>> Make iovisor/ubpf project be a git submodule for QEMU. > > >>>> It will auto clone ubpf project when configure QEMU. > > >>> > > >>> I don't think we need todo this. As it is brand new functionality we > > >>> don't have any back compat issues. We should just expect the distros > > >>> to ship ubpf if they want their QEMU builds to take advantage of it. > > >>> > > >> > > >> Yes, agree. It's the best way to use the uBPF project. > > >> But current status is distros(ubuntu, RHEL...) does not ship the > > >> iovisor/ubpf like the iovisor/bcc. So I have to do it. > > >> Or do you have any better suggestions? > > > > > > If distros want to support the functionality, they can add packages > > > for it IMHO. > > > > Yes, let's please avoid new submodules. Submodules can sometimes be a > > real PITA (e.g. if you forget to update before rsync'ing your code to a > > machine that has limited internet access), and if users install QEMU from > > sources, they can also install ubpf from sources, too. > > And if distros want to support this feature, they can package ubpf on their > > own, as Daniel said. > > Hi Daniel and Thomas, > > I don't know much the background history of QEMU submodules, but meson build > is a submodule for QEMU too. It means user can't install QEMU from sources > with limited internet access. > And back to Daniel's comments, Yes, the best way is distros add the ubpf packages, > But maybe it's too late to implement new features for us. We can introduce the submodule now and > auto change to the distros's lib when distros add it. For example QEMU's submodule SLIRP do it in the same way. > It's already added by most distros and still as a QEMU submodule. It make user experience the latest technology > with no other dependencies. uBPF infrastructure have the ability to extend the capabilities without requiring > changing source code. If we not allow it, we have to re-implement all the eBPF assembler, disassembler, > interpreter, and JIT compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by license issue). Slirp is a different scenario. That was functionality that was historically integrated into QEMU and was then spun out into a standalone project. Since we had existing users on existing distro releases dependant on Slirp, we wanted to give a smooth upgrade experiance by bundling Slirp. Essentially the goal was to avoid the regression if someone deployed new QEMU on existing distros. Meson is a fairly similar scenario. We wanted to swap the build system in QEMU over to Meson, and that change would affect all existing users of QEMU. Many distros didn't have a new enough meson, and so bundling it in QEMU enables us to give a smooth upgrade path without any regression for existing users on existing distros. This patch, however, is proposing an entirely new piece of functionality that has no existing users and even once present will be used by relatively few users compartively speaking. As such there is no upgrade compatibility / regression scenario that we need to worry about. Anyone interested in the new functionality can be reasonably asked to either wait for the distro to package it, or build it themselves. With regards, Daniel
> -----Original Message----- > From: Daniel P. Berrangé <berrange@redhat.com> > Sent: Monday, June 20, 2022 6:01 PM > To: Zhang, Chen <chen.zhang@intel.com> > Cc: Thomas Huth <thuth@redhat.com>; Jason Wang > <jasowang@redhat.com>; qemu-dev <qemu-devel@nongnu.org>; Paolo > Bonzini <pbonzini@redhat.com>; Eduardo Habkost <eduardo@habkost.net>; > Eric Blake <eblake@redhat.com>; Markus Armbruster > <armbru@redhat.com>; Peter Maydell <peter.maydell@linaro.org>; Laurent > Vivier <lvivier@redhat.com>; Yuri Benditovich > <yuri.benditovich@daynix.com>; Andrew Melnychenko > <andrew@daynix.com> > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > submodule for QEMU > > On Mon, Jun 20, 2022 at 09:29:05AM +0000, Zhang, Chen wrote: > > > > > > > > On 20/06/2022 10.11, Daniel P. Berrangé wrote: > > > > On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > > > >> > > > >> > > > >>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > > >>>> Make iovisor/ubpf project be a git submodule for QEMU. > > > >>>> It will auto clone ubpf project when configure QEMU. > > > >>> > > > >>> I don't think we need todo this. As it is brand new > > > >>> functionality we don't have any back compat issues. We should > > > >>> just expect the distros to ship ubpf if they want their QEMU builds to > take advantage of it. > > > >>> > > > >> > > > >> Yes, agree. It's the best way to use the uBPF project. > > > >> But current status is distros(ubuntu, RHEL...) does not ship the > > > >> iovisor/ubpf like the iovisor/bcc. So I have to do it. > > > >> Or do you have any better suggestions? > > > > > > > > If distros want to support the functionality, they can add > > > > packages for it IMHO. > > > > > > Yes, let's please avoid new submodules. Submodules can sometimes be > > > a real PITA (e.g. if you forget to update before rsync'ing your code > > > to a machine that has limited internet access), and if users install > > > QEMU from sources, they can also install ubpf from sources, too. > > > And if distros want to support this feature, they can package ubpf > > > on their own, as Daniel said. > > > > Hi Daniel and Thomas, > > > > I don't know much the background history of QEMU submodules, but > meson > > build is a submodule for QEMU too. It means user can't install QEMU > > from sources with limited internet access. > > And back to Daniel's comments, Yes, the best way is distros add the > > ubpf packages, But maybe it's too late to implement new features for > > us. We can introduce the submodule now and auto change to the distros's > lib when distros add it. For example QEMU's submodule SLIRP do it in the > same way. > > It's already added by most distros and still as a QEMU submodule. It > > make user experience the latest technology with no other dependencies. > > uBPF infrastructure have the ability to extend the capabilities > > without requiring changing source code. If we not allow it, we have to re- > implement all the eBPF assembler, disassembler, interpreter, and JIT > compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by > license issue). > > Slirp is a different scenario. That was functionality that was historically > integrated into QEMU and was then spun out into a standalone project. Since > we had existing users on existing distro releases dependant on Slirp, we > wanted to give a smooth upgrade experiance by bundling Slirp. Essentially > the goal was to avoid the regression if someone deployed new QEMU on > existing distros. > > Meson is a fairly similar scenario. We wanted to swap the build system in > QEMU over to Meson, and that change would affect all existing users of > QEMU. > Many distros didn't have a new enough meson, and so bundling it in QEMU > enables us to give a smooth upgrade path without any regression for existing > users on existing distros. > > This patch, however, is proposing an entirely new piece of functionality that > has no existing users and even once present will be used by relatively few > users compartively speaking. As such there is no upgrade compatibility / > regression scenario that we need to worry about. Anyone interested in the > new functionality can be reasonably asked to either wait for the distro to > package it, or build it themselves. > OK, got your point. For this series, should we introduce an external library "libubpf" in QEMU configure? If this library is found, the relevant files will be compiled and the feature can be enabled in QEMU. Thanks Chen > With regards, > Daniel > -- > |: https://berrange.com -o- > https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- > https://www.instagram.com/dberrange :|
> -----Original Message----- > From: Thomas Huth <thuth@redhat.com> > Sent: Monday, June 20, 2022 5:44 PM > To: Zhang, Chen <chen.zhang@intel.com>; Daniel P. Berrangé > <berrange@redhat.com> > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus > Armbruster <armbru@redhat.com>; Peter Maydell > <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri > Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > <andrew@daynix.com> > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > submodule for QEMU > > On 20/06/2022 11.29, Zhang, Chen wrote: > > > > > >> -----Original Message----- > >> From: Thomas Huth <thuth@redhat.com> > >> Sent: Monday, June 20, 2022 4:47 PM > >> To: Daniel P. Berrangé <berrange@redhat.com>; Zhang, Chen > >> <chen.zhang@intel.com> > >> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > >> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > >> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > Markus > >> Armbruster <armbru@redhat.com>; Peter Maydell > >> <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri > >> Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > >> <andrew@daynix.com> > >> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as > >> a submodule for QEMU > >> > >> On 20/06/2022 10.11, Daniel P. Berrangé wrote: > >>> On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > >>>> > >>>> > >>>>> -----Original Message----- > >>>>> From: Daniel P. Berrangé <berrange@redhat.com> > >>>>> Sent: Friday, June 17, 2022 4:05 PM > >>>>> To: Zhang, Chen <chen.zhang@intel.com> > >>>>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > >>>>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > >>>>> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > >>>>> Markus Armbruster <armbru@redhat.com>; Peter Maydell > >>>>> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; > >> Laurent > >>>>> Vivier <lvivier@redhat.com>; Yuri Benditovich > >>>>> <yuri.benditovich@daynix.com>; Andrew Melnychenko > >>>>> <andrew@daynix.com> > >>>>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project > >>>>> as a submodule for QEMU > >>>>> > >>>>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > >>>>>> Make iovisor/ubpf project be a git submodule for QEMU. > >>>>>> It will auto clone ubpf project when configure QEMU. > >>>>> > >>>>> I don't think we need todo this. As it is brand new functionality > >>>>> we don't have any back compat issues. We should just expect the > >>>>> distros to ship ubpf if they want their QEMU builds to take advantage > of it. > >>>>> > >>>> > >>>> Yes, agree. It's the best way to use the uBPF project. > >>>> But current status is distros(ubuntu, RHEL...) does not ship the > >>>> iovisor/ubpf like the iovisor/bcc. So I have to do it. > >>>> Or do you have any better suggestions? > >>> > >>> If distros want to support the functionality, they can add packages > >>> for it IMHO. > >> > >> Yes, let's please avoid new submodules. Submodules can sometimes be a > >> real PITA (e.g. if you forget to update before rsync'ing your code to > >> a machine that has limited internet access), and if users install > >> QEMU from sources, they can also install ubpf from sources, too. > >> And if distros want to support this feature, they can package ubpf on > >> their own, as Daniel said. > > > > Hi Daniel and Thomas, > > > > I don't know much the background history of QEMU submodules, but > meson > > build is a submodule for QEMU too. It means user can't install QEMU > > from sources with limited internet access. > > There is no written policy, but I think the general consensus is that we only > ship code in submodules if: > > 1) It's not available in a required version in distros yet > > and > > 2) it is essentially required to build QEMU (like meson) or if the feature has > been part of the QEMU sources before and then moved to a separate > repository (like slirp). > > We ship meson as a submodule since we require some meson features that > are not available with the meson versions in the distros yet. Once the distros > catch up, we'll likely remove the meson submodule from QEMU. > > > And back to Daniel's comments, Yes, the best way is distros add the > > ubpf packages, But maybe it's too late to implement new features for > > us. We can introduce the submodule now and auto change to the distros's > lib when distros add it. For example QEMU's submodule SLIRP do it in the > same way. > > slirp used to be part of the QEMU repository, but then has been moved to a > separate project a while ago. However, at that point in time there weren't > any packages ins distros yet, so we had to include it as a submodule. > > Now that the distros ship it, too, we're planning to remove the slirp > submodule from QEMU soon, see: > > https://lists.gnu.org/archive/html/qemu-devel/2022-04/msg00974.html > > > It make user experience the latest technology with no other > > dependencies. > > Well, that's only true if we update the submodule in QEMU regularly. If we > forget to update, we could easily miss some important (maybe even security > related) fixes from the upstream projects. This can be a nightmare for distros, > when they then have to go around and look into each and every projects > whether they embed a certain code module that needs a CVE fix. It's better > if it can be fixed in one central spot instead. > > > uBPF infrastructure have the ability to extend the capabilities > > without requiring changing source code. If we not allow it, we have to > > re-implement all the eBPF assembler, disassembler, interpreter, and JIT > compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by > license issue). > > Not sure whether I understood that statement right ... nobody said that > QEMU should not allow it - we just suggested to rely on a system installation > of ubpf instead of embedding the code. Or is that not possible?? (I don't > know that project yet - isn't it possible to compile it as a shared library?) Thanks for your details explanation. It looks better to introduce the uBPF shared library for QEMU. For example: ./configure --ubpf-lib=path If yes, I think it's fine for me. Thanks Chen > > Thomas
On Mon, Jun 20, 2022 at 10:29:14AM +0000, Zhang, Chen wrote: > > > > -----Original Message----- > > From: Thomas Huth <thuth@redhat.com> > > Sent: Monday, June 20, 2022 5:44 PM > > To: Zhang, Chen <chen.zhang@intel.com>; Daniel P. Berrangé > > <berrange@redhat.com> > > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; Markus > > Armbruster <armbru@redhat.com>; Peter Maydell > > <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri > > Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > > <andrew@daynix.com> > > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > > submodule for QEMU > > > > On 20/06/2022 11.29, Zhang, Chen wrote: > > > > > > > > >> -----Original Message----- > > >> From: Thomas Huth <thuth@redhat.com> > > >> Sent: Monday, June 20, 2022 4:47 PM > > >> To: Daniel P. Berrangé <berrange@redhat.com>; Zhang, Chen > > >> <chen.zhang@intel.com> > > >> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > >> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > >> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > > Markus > > >> Armbruster <armbru@redhat.com>; Peter Maydell > > >> <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; Yuri > > >> Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > > >> <andrew@daynix.com> > > >> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as > > >> a submodule for QEMU > > >> > > >> On 20/06/2022 10.11, Daniel P. Berrangé wrote: > > >>> On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > > >>>> > > >>>> > > >>>>> -----Original Message----- > > >>>>> From: Daniel P. Berrangé <berrange@redhat.com> > > >>>>> Sent: Friday, June 17, 2022 4:05 PM > > >>>>> To: Zhang, Chen <chen.zhang@intel.com> > > >>>>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > >>>>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > >>>>> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > > >>>>> Markus Armbruster <armbru@redhat.com>; Peter Maydell > > >>>>> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>; > > >> Laurent > > >>>>> Vivier <lvivier@redhat.com>; Yuri Benditovich > > >>>>> <yuri.benditovich@daynix.com>; Andrew Melnychenko > > >>>>> <andrew@daynix.com> > > >>>>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project > > >>>>> as a submodule for QEMU > > >>>>> > > >>>>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > >>>>>> Make iovisor/ubpf project be a git submodule for QEMU. > > >>>>>> It will auto clone ubpf project when configure QEMU. > > >>>>> > > >>>>> I don't think we need todo this. As it is brand new functionality > > >>>>> we don't have any back compat issues. We should just expect the > > >>>>> distros to ship ubpf if they want their QEMU builds to take advantage > > of it. > > >>>>> > > >>>> > > >>>> Yes, agree. It's the best way to use the uBPF project. > > >>>> But current status is distros(ubuntu, RHEL...) does not ship the > > >>>> iovisor/ubpf like the iovisor/bcc. So I have to do it. > > >>>> Or do you have any better suggestions? > > >>> > > >>> If distros want to support the functionality, they can add packages > > >>> for it IMHO. > > >> > > >> Yes, let's please avoid new submodules. Submodules can sometimes be a > > >> real PITA (e.g. if you forget to update before rsync'ing your code to > > >> a machine that has limited internet access), and if users install > > >> QEMU from sources, they can also install ubpf from sources, too. > > >> And if distros want to support this feature, they can package ubpf on > > >> their own, as Daniel said. > > > > > > Hi Daniel and Thomas, > > > > > > I don't know much the background history of QEMU submodules, but > > meson > > > build is a submodule for QEMU too. It means user can't install QEMU > > > from sources with limited internet access. > > > > There is no written policy, but I think the general consensus is that we only > > ship code in submodules if: > > > > 1) It's not available in a required version in distros yet > > > > and > > > > 2) it is essentially required to build QEMU (like meson) or if the feature has > > been part of the QEMU sources before and then moved to a separate > > repository (like slirp). > > > > We ship meson as a submodule since we require some meson features that > > are not available with the meson versions in the distros yet. Once the distros > > catch up, we'll likely remove the meson submodule from QEMU. > > > > > And back to Daniel's comments, Yes, the best way is distros add the > > > ubpf packages, But maybe it's too late to implement new features for > > > us. We can introduce the submodule now and auto change to the distros's > > lib when distros add it. For example QEMU's submodule SLIRP do it in the > > same way. > > > > slirp used to be part of the QEMU repository, but then has been moved to a > > separate project a while ago. However, at that point in time there weren't > > any packages ins distros yet, so we had to include it as a submodule. > > > > Now that the distros ship it, too, we're planning to remove the slirp > > submodule from QEMU soon, see: > > > > https://lists.gnu.org/archive/html/qemu-devel/2022-04/msg00974.html > > > > > It make user experience the latest technology with no other > > > dependencies. > > > > Well, that's only true if we update the submodule in QEMU regularly. If we > > forget to update, we could easily miss some important (maybe even security > > related) fixes from the upstream projects. This can be a nightmare for distros, > > when they then have to go around and look into each and every projects > > whether they embed a certain code module that needs a CVE fix. It's better > > if it can be fixed in one central spot instead. > > > > > uBPF infrastructure have the ability to extend the capabilities > > > without requiring changing source code. If we not allow it, we have to > > > re-implement all the eBPF assembler, disassembler, interpreter, and JIT > > compiler like DPDK userspace eBPF support (DPDK can't use ubpf project by > > license issue). > > > > Not sure whether I understood that statement right ... nobody said that > > QEMU should not allow it - we just suggested to rely on a system installation > > of ubpf instead of embedding the code. Or is that not possible?? (I don't > > know that project yet - isn't it possible to compile it as a shared library?) > > Thanks for your details explanation. > It looks better to introduce the uBPF shared library for QEMU. > For example: > ./configure --ubpf-lib=path I've not looked, so maybe it already does this, but ideally 'uBPF' would ship a 'pkg-config' file, so that apps can automatically find it and set the right cflags/libs etc for the compiler. For configure integration, normally we'd expect it to be --enable-ubpf/--disable-ubpf, with it automatically enabling itself if the pkg-config file is found. Take a look at handling of some existing libraries we depend on for examples. With regards, Daniel
> -----Original Message----- > From: Daniel P. Berrangé <berrange@redhat.com> > Sent: Monday, June 20, 2022 6:37 PM > To: Zhang, Chen <chen.zhang@intel.com> > Cc: Thomas Huth <thuth@redhat.com>; Jason Wang > <jasowang@redhat.com>; qemu-dev <qemu-devel@nongnu.org>; Paolo > Bonzini <pbonzini@redhat.com>; Eduardo Habkost <eduardo@habkost.net>; > Eric Blake <eblake@redhat.com>; Markus Armbruster > <armbru@redhat.com>; Peter Maydell <peter.maydell@linaro.org>; Laurent > Vivier <lvivier@redhat.com>; Yuri Benditovich > <yuri.benditovich@daynix.com>; Andrew Melnychenko > <andrew@daynix.com> > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project as a > submodule for QEMU > > On Mon, Jun 20, 2022 at 10:29:14AM +0000, Zhang, Chen wrote: > > > > > > > -----Original Message----- > > > From: Thomas Huth <thuth@redhat.com> > > > Sent: Monday, June 20, 2022 5:44 PM > > > To: Zhang, Chen <chen.zhang@intel.com>; Daniel P. Berrangé > > > <berrange@redhat.com> > > > Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > > devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > > Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > > > Markus Armbruster <armbru@redhat.com>; Peter Maydell > > > <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; > > > Yuri Benditovich <yuri.benditovich@daynix.com>; Andrew Melnychenko > > > <andrew@daynix.com> > > > Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf project > > > as a submodule for QEMU > > > > > > On 20/06/2022 11.29, Zhang, Chen wrote: > > > > > > > > > > > >> -----Original Message----- > > > >> From: Thomas Huth <thuth@redhat.com> > > > >> Sent: Monday, June 20, 2022 4:47 PM > > > >> To: Daniel P. Berrangé <berrange@redhat.com>; Zhang, Chen > > > >> <chen.zhang@intel.com> > > > >> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > > >> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; Eduardo > > > >> Habkost <eduardo@habkost.net>; Eric Blake <eblake@redhat.com>; > > > Markus > > > >> Armbruster <armbru@redhat.com>; Peter Maydell > > > >> <peter.maydell@linaro.org>; Laurent Vivier <lvivier@redhat.com>; > > > >> Yuri Benditovich <yuri.benditovich@daynix.com>; Andrew > > > >> Melnychenko <andrew@daynix.com> > > > >> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf > > > >> project as a submodule for QEMU > > > >> > > > >> On 20/06/2022 10.11, Daniel P. Berrangé wrote: > > > >>> On Mon, Jun 20, 2022 at 05:59:06AM +0000, Zhang, Chen wrote: > > > >>>> > > > >>>> > > > >>>>> -----Original Message----- > > > >>>>> From: Daniel P. Berrangé <berrange@redhat.com> > > > >>>>> Sent: Friday, June 17, 2022 4:05 PM > > > >>>>> To: Zhang, Chen <chen.zhang@intel.com> > > > >>>>> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu- > > > >>>>> devel@nongnu.org>; Paolo Bonzini <pbonzini@redhat.com>; > > > >>>>> Eduardo Habkost <eduardo@habkost.net>; Eric Blake > > > >>>>> <eblake@redhat.com>; Markus Armbruster > <armbru@redhat.com>; > > > >>>>> Peter Maydell <peter.maydell@linaro.org>; Thomas Huth > > > >>>>> <thuth@redhat.com>; > > > >> Laurent > > > >>>>> Vivier <lvivier@redhat.com>; Yuri Benditovich > > > >>>>> <yuri.benditovich@daynix.com>; Andrew Melnychenko > > > >>>>> <andrew@daynix.com> > > > >>>>> Subject: Re: [RFC PATCH 01/12] configure: Add iovisor/ubpf > > > >>>>> project as a submodule for QEMU > > > >>>>> > > > >>>>> On Fri, Jun 17, 2022 at 03:36:19PM +0800, Zhang Chen wrote: > > > >>>>>> Make iovisor/ubpf project be a git submodule for QEMU. > > > >>>>>> It will auto clone ubpf project when configure QEMU. > > > >>>>> > > > >>>>> I don't think we need todo this. As it is brand new > > > >>>>> functionality we don't have any back compat issues. We should > > > >>>>> just expect the distros to ship ubpf if they want their QEMU > > > >>>>> builds to take advantage > > > of it. > > > >>>>> > > > >>>> > > > >>>> Yes, agree. It's the best way to use the uBPF project. > > > >>>> But current status is distros(ubuntu, RHEL...) does not ship > > > >>>> the iovisor/ubpf like the iovisor/bcc. So I have to do it. > > > >>>> Or do you have any better suggestions? > > > >>> > > > >>> If distros want to support the functionality, they can add > > > >>> packages for it IMHO. > > > >> > > > >> Yes, let's please avoid new submodules. Submodules can sometimes > > > >> be a real PITA (e.g. if you forget to update before rsync'ing > > > >> your code to a machine that has limited internet access), and if > > > >> users install QEMU from sources, they can also install ubpf from > sources, too. > > > >> And if distros want to support this feature, they can package > > > >> ubpf on their own, as Daniel said. > > > > > > > > Hi Daniel and Thomas, > > > > > > > > I don't know much the background history of QEMU submodules, but > > > meson > > > > build is a submodule for QEMU too. It means user can't install > > > > QEMU from sources with limited internet access. > > > > > > There is no written policy, but I think the general consensus is > > > that we only ship code in submodules if: > > > > > > 1) It's not available in a required version in distros yet > > > > > > and > > > > > > 2) it is essentially required to build QEMU (like meson) or if the > > > feature has been part of the QEMU sources before and then moved to a > > > separate repository (like slirp). > > > > > > We ship meson as a submodule since we require some meson features > > > that are not available with the meson versions in the distros yet. > > > Once the distros catch up, we'll likely remove the meson submodule from > QEMU. > > > > > > > And back to Daniel's comments, Yes, the best way is distros add > > > > the ubpf packages, But maybe it's too late to implement new > > > > features for us. We can introduce the submodule now and auto > > > > change to the distros's > > > lib when distros add it. For example QEMU's submodule SLIRP do it > > > in the same way. > > > > > > slirp used to be part of the QEMU repository, but then has been > > > moved to a separate project a while ago. However, at that point in > > > time there weren't any packages ins distros yet, so we had to include it as > a submodule. > > > > > > Now that the distros ship it, too, we're planning to remove the > > > slirp submodule from QEMU soon, see: > > > > > > > > > https://lists.gnu.org/archive/html/qemu-devel/2022-04/msg00974.html > > > > > > > It make user experience the latest technology with no other > > > > dependencies. > > > > > > Well, that's only true if we update the submodule in QEMU regularly. > > > If we forget to update, we could easily miss some important (maybe > > > even security > > > related) fixes from the upstream projects. This can be a nightmare > > > for distros, when they then have to go around and look into each and > > > every projects whether they embed a certain code module that needs a > > > CVE fix. It's better if it can be fixed in one central spot instead. > > > > > > > uBPF infrastructure have the ability to extend the capabilities > > > > without requiring changing source code. If we not allow it, we > > > > have to re-implement all the eBPF assembler, disassembler, > > > > interpreter, and JIT > > > compiler like DPDK userspace eBPF support (DPDK can't use ubpf > > > project by license issue). > > > > > > Not sure whether I understood that statement right ... nobody said > > > that QEMU should not allow it - we just suggested to rely on a > > > system installation of ubpf instead of embedding the code. Or is > > > that not possible?? (I don't know that project yet - isn't it > > > possible to compile it as a shared library?) > > > > Thanks for your details explanation. > > It looks better to introduce the uBPF shared library for QEMU. > > For example: > > ./configure --ubpf-lib=path > > I've not looked, so maybe it already does this, but ideally 'uBPF' > would ship a 'pkg-config' file, so that apps can automatically find it and set > the right cflags/libs etc for the compiler. For configure integration, normally > we'd expect it to be --enable-ubpf/--disable-ubpf, with it automatically > enabling itself if the pkg-config file is found. > Take a look at handling of some existing libraries we depend on for examples. > OK, thanks your comments. I reviewed uBPF code, but no pkg-config file. The make install just copy the libubpf.so/.a to /usr/lib. Fortunately, writing this file looks easy. I will try to do it and make QEMU use the libubpf.so like "pixman". Thanks Chen > With regards, > Daniel > -- > |: https://berrange.com -o- > https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- > https://www.instagram.com/dberrange :|
diff --git a/.gitmodules b/.gitmodules index b8bff47df8..30fb082f39 100644 --- a/.gitmodules +++ b/.gitmodules @@ -64,3 +64,6 @@ [submodule "tests/lcitool/libvirt-ci"] path = tests/lcitool/libvirt-ci url = https://gitlab.com/libvirt/libvirt-ci.git +[submodule "ubpf"] + path = ubpf + url = https://github.com/iovisor/ubpf.git diff --git a/configure b/configure index e69537c756..7dde1429dc 100755 --- a/configure +++ b/configure @@ -326,6 +326,7 @@ else slirp="auto" fi fdt="auto" +ubpf="auto" # 2. Automatically enable/disable other options tcg="enabled" @@ -820,6 +821,14 @@ for opt do ;; --enable-slirp=*) slirp="$optarg" ;; + --disable-ubpf) ubpf="disabled" + ;; + --enable-ubpf) ubpf="enabled" + ;; + --enable-ubpf=git) ubpf="internal" + ;; + --enable-ubpf=*) ubpf="$optarg" + ;; --disable-tcg) tcg="disabled" plugins="no" ;; @@ -2176,6 +2185,16 @@ if test "$have_ubsan" = "yes"; then QEMU_LDFLAGS="-fsanitize=undefined $QEMU_LDFLAGS" fi +########################################## +# check for ubpf + +case "$ubpf" in + auto | enabled | internal) + # Simpler to always update submodule, even if not needed. + git_submodules="${git_submodules} ubpf" + ;; +esac + ########################################## # Exclude --warn-common with TSan to suppress warnings from the TSan libraries. @@ -2664,6 +2683,7 @@ if test "$skip_meson" = no; then # QEMU options test "$cfi" != false && meson_option_add "-Dcfi=$cfi" test "$fdt" != auto && meson_option_add "-Dfdt=$fdt" + test "$ubpf" != auto && meson_option_add "-Dubpf=$ubpf" test -n "${LIB_FUZZING_ENGINE+xxx}" && meson_option_add "-Dfuzzing_engine=$LIB_FUZZING_ENGINE" test "$qemu_suffix" != qemu && meson_option_add "-Dqemu_suffix=$qemu_suffix" test "$slirp" != auto && meson_option_add "-Dslirp=$slirp" diff --git a/ubpf b/ubpf new file mode 160000 index 0000000000..0dd334daf4 --- /dev/null +++ b/ubpf @@ -0,0 +1 @@ +Subproject commit 0dd334daf4849137fa40d2b7676d2bf920d5c81d
Make iovisor/ubpf project be a git submodule for QEMU. It will auto clone ubpf project when configure QEMU. Signed-off-by: Zhang Chen <chen.zhang@intel.com> --- .gitmodules | 3 +++ configure | 20 ++++++++++++++++++++ ubpf | 1 + 3 files changed, 24 insertions(+) create mode 160000 ubpf