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(-) >> >