On Wed, 27 Jan 2021 at 08:28, Wanpeng Li <[email protected]> wrote: > > On Wed, 27 Jan 2021 at 01:26, Paolo Bonzini <[email protected]> wrote: > > > > On 26/01/21 02:28, Wanpeng Li wrote: > > > pingļ¼ > > > On Mon, 18 Jan 2021 at 17:08, Wanpeng Li <[email protected]> wrote: > > >> > > >> From: Wanpeng Li <[email protected]> > > >> > > >> The per-cpu vsyscall pvclock data pointer assigns either an element of > > >> the > > >> static array hv_clock_boot (#vCPU <= 64) or dynamically allocated memory > > >> hvclock_mem (vCPU > 64), the dynamically memory will not be allocated if > > >> kvmclock vsyscall is disabled, this can result in cpu hotpluged fails in > > >> kvmclock_setup_percpu() which returns -ENOMEM. This patch fixes it by not > > >> assigning vsyscall pvclock data pointer if kvmclock vdso_clock_mode is > > >> not > > >> VDSO_CLOCKMODE_PVCLOCK. > > > > I am sorry, I still cannot figure out this patch. > > > > Is hotplug still broken if kvm vsyscall is enabled? > > Just when kvm vsyscall is disabled. :) > > # lscpu > Architecture: x86_64 > CPU op-mode(s): 32-bit, 64-bit > Byte Order: Little Endian > CPU(s): 88 > On-line CPU(s) list: 0-63 > Off-line CPU(s) list: 64-87 > > # cat /proc/cmdline > BOOT_IMAGE=/vmlinuz-5.10.0-rc3-tlinux2-0050+ root=/dev/mapper/cl-root > ro rd.lvm.lv=cl/root rhgb quiet console=ttyS0 LANG=en_US > .UTF-8 no-kvmclock-vsyscall > > # echo 1 > /sys/devices/system/cpu/cpu76/online > -bash: echo: write error: Cannot allocate memory
The original bug report is here. https://bugzilla.kernel.org/show_bug.cgi?id=210213 Wanpeng
