| Message ID | 20190520071514.9308-1-clg@kaod.org |
|---|---|
| Headers | show |
| Series | KVM: PPC: Book3S HV: XIVE: assorted fixes on vCPU and RAM limits | expand |
On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: > Hello, > > Here are a couple of fixes for issues in the XIVE KVM device when > testing the limits : RAM size and number of vCPUS. How serious are the problems these patches fix? I'm wondering if I need to make a backport for RHEL8.1. > > Based on 5.2-rc1. > > Available on GitHub: > > https://github.com/legoater/linux/commits/xive-5.2 > > Thanks, > > C. > > Cédric Le Goater (3): > KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released > KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when > reseting > KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU > identifier > > arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- > 1 file changed, 27 insertions(+), 19 deletions(-) >
On Thu, 23 May 2019 09:30:43 +1000 David Gibson <david@gibson.dropbear.id.au> wrote: > On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: > > Hello, > > > > Here are a couple of fixes for issues in the XIVE KVM device when > > testing the limits : RAM size and number of vCPUS. > > How serious are the problems these patches fix? I'm wondering if I > need to make a backport for RHEL8.1. > Patch 2/3 fixes a QEMU error when hot-unplugging a vCPU: qemu-system-ppc64: KVM_SET_DEVICE_ATTR failed: Group 4 attr 0x0000000000000046: Invalid argument Patch 3/3 fixes an issue where the guest freezes at some point when doing vCPU hot-plug/unplug in a loop. Both issues have a BZ at IBM. They can be mirrored to RH if needed. > > > > Based on 5.2-rc1. > > > > Available on GitHub: > > > > https://github.com/legoater/linux/commits/xive-5.2 > > > > Thanks, > > > > C. > > > > Cédric Le Goater (3): > > KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released > > KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when > > reseting > > KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU > > identifier > > > > arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- > > 1 file changed, 27 insertions(+), 19 deletions(-) > > >
On 5/23/19 1:30 AM, David Gibson wrote: > On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: >> Hello, >> >> Here are a couple of fixes for issues in the XIVE KVM device when >> testing the limits : RAM size and number of vCPUS. This summary is wrong. RAM size was fixed in QEMU. > How serious are the problems these patches fix? I'm wondering if I > need to make a backport for RHEL8.1. Patch 1 is a cleanup patch. It does not fix any critical issues. Patch 2 fixes CPU hotplug. The test on the EQ flag is at the wrong place :/ This is important I think. Patch 3 fixes the maximum number of vCPUS supported. This one is less important maybe, unless we want to run a guest with 1024 vCPUs. Which is quite slow to run on most P9 systems. QEMU emits a warning : warning: Number of SMP cpus requested (1024) exceeds the recommended cpus supported by KVM (120) May be we should refuse to run QEMU when that number is above a certain threshold ? C. >> >> Based on 5.2-rc1. >> >> Available on GitHub: >> >> https://github.com/legoater/linux/commits/xive-5.2 >> >> Thanks, >> >> C. >> >> Cédric Le Goater (3): >> KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released >> KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when >> reseting >> KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU >> identifier >> >> arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- >> 1 file changed, 27 insertions(+), 19 deletions(-) >> >
On Thu, May 23, 2019 at 08:01:23AM +0200, Greg Kurz wrote: > On Thu, 23 May 2019 09:30:43 +1000 > David Gibson <david@gibson.dropbear.id.au> wrote: > > > On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: > > > Hello, > > > > > > Here are a couple of fixes for issues in the XIVE KVM device when > > > testing the limits : RAM size and number of vCPUS. > > > > How serious are the problems these patches fix? I'm wondering if I > > need to make a backport for RHEL8.1. > > > > Patch 2/3 fixes a QEMU error when hot-unplugging a vCPU: > > qemu-system-ppc64: KVM_SET_DEVICE_ATTR failed: Group 4 attr 0x0000000000000046: Invalid argument > > > Patch 3/3 fixes an issue where the guest freezes at some point when doing > vCPU hot-plug/unplug in a loop. Oh.. weird. It's not clear to me how it would do that. > Both issues have a BZ at IBM. They can be mirrored to RH if needed. That would be helpful, thanks. > > > > > > > Based on 5.2-rc1. > > > > > > Available on GitHub: > > > > > > https://github.com/legoater/linux/commits/xive-5.2 > > > > > > Thanks, > > > > > > C. > > > > > > Cédric Le Goater (3): > > > KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released > > > KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when > > > reseting > > > KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU > > > identifier > > > > > > arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- > > > 1 file changed, 27 insertions(+), 19 deletions(-) > > > > > >
On Thu, 23 May 2019 16:27:15 +1000 David Gibson <david@gibson.dropbear.id.au> wrote: > On Thu, May 23, 2019 at 08:01:23AM +0200, Greg Kurz wrote: > > On Thu, 23 May 2019 09:30:43 +1000 > > David Gibson <david@gibson.dropbear.id.au> wrote: > > > > > On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: > > > > Hello, > > > > > > > > Here are a couple of fixes for issues in the XIVE KVM device when > > > > testing the limits : RAM size and number of vCPUS. > > > > > > How serious are the problems these patches fix? I'm wondering if I > > > need to make a backport for RHEL8.1. > > > > > > > Patch 2/3 fixes a QEMU error when hot-unplugging a vCPU: > > > > qemu-system-ppc64: KVM_SET_DEVICE_ATTR failed: Group 4 attr 0x0000000000000046: Invalid argument > > > > > > Patch 3/3 fixes an issue where the guest freezes at some point when doing > > vCPU hot-plug/unplug in a loop. > > Oh.. weird. It's not clear to me how it would do that. > Cedric provided a better description in some other mail: guest with 1024 vCPUs. > > Both issues have a BZ at IBM. They can be mirrored to RH if needed. > > That would be helpful, thanks. > Ok, I'll take care of that. > > > > > > > > > > > > > Based on 5.2-rc1. > > > > > > > > Available on GitHub: > > > > > > > > https://github.com/legoater/linux/commits/xive-5.2 > > > > > > > > Thanks, > > > > > > > > C. > > > > > > > > Cédric Le Goater (3): > > > > KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released > > > > KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when > > > > reseting > > > > KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU > > > > identifier > > > > > > > > arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- > > > > 1 file changed, 27 insertions(+), 19 deletions(-) > > > > > > > > > > > >
On Mon, May 20, 2019 at 09:15:11AM +0200, Cédric Le Goater wrote: > Hello, > > Here are a couple of fixes for issues in the XIVE KVM device when > testing the limits : RAM size and number of vCPUS. > > Based on 5.2-rc1. > > Available on GitHub: > > https://github.com/legoater/linux/commits/xive-5.2 > > Thanks, > > C. > > Cédric Le Goater (3): > KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released > KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when > reseting > KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU > identifier Thanks, series applied to my kvm-ppc-fixes branch. Paul.
Hello, Here are a couple of fixes for issues in the XIVE KVM device when testing the limits : RAM size and number of vCPUS. Based on 5.2-rc1. Available on GitHub: https://github.com/legoater/linux/commits/xive-5.2 Thanks, C. Cédric Le Goater (3): KVM: PPC: Book3S HV: XIVE: clear file mapping when device is released KVM: PPC: Book3S HV: XIVE: do not test the EQ flag validity when reseting KVM: PPC: Book3S HV: XIVE: fix the enforced limit on the vCPU identifier arch/powerpc/kvm/book3s_xive_native.c | 46 ++++++++++++++++----------- 1 file changed, 27 insertions(+), 19 deletions(-)