e5d9b714fe
For root partition the VP assist pages are pre-determined by the hypervisor. The root kernel is not allowed to change them to different locations. And thus, we are getting below stack as in current implementation root is trying to perform write to specific MSR. [ 2.778197] unchecked MSR access error: WRMSR to 0x40000073 (tried to write 0x0000000145ac5001) at rIP: 0xffffffff810c1084 (native_write_msr+0x4/0x30) [ 2.784867] Call Trace: [ 2.791507] hv_cpu_init+0xf1/0x1c0 [ 2.798144] ? hyperv_report_panic+0xd0/0xd0 [ 2.804806] cpuhp_invoke_callback+0x11a/0x440 [ 2.811465] ? hv_resume+0x90/0x90 [ 2.818137] cpuhp_issue_call+0x126/0x130 [ 2.824782] __cpuhp_setup_state_cpuslocked+0x102/0x2b0 [ 2.831427] ? hyperv_report_panic+0xd0/0xd0 [ 2.838075] ? hyperv_report_panic+0xd0/0xd0 [ 2.844723] ? hv_resume+0x90/0x90 [ 2.851375] __cpuhp_setup_state+0x3d/0x90 [ 2.858030] hyperv_init+0x14e/0x410 [ 2.864689] ? enable_IR_x2apic+0x190/0x1a0 [ 2.871349] apic_intr_mode_init+0x8b/0x100 [ 2.878017] x86_late_time_init+0x20/0x30 [ 2.884675] start_kernel+0x459/0x4fb [ 2.891329] secondary_startup_64_no_verify+0xb0/0xbb Since the hypervisor already provides the VP assist pages for root partition, we need to memremap the memory from hypervisor for root kernel to use. The mapping is done in hv_cpu_init during bringup and is unmapped in hv_cpu_die during teardown. Signed-off-by: Praveen Kumar <kumarpraveen@linux.microsoft.com> Reviewed-by: Sunil Muthuswamy <sunilmut@microsoft.com> Link: https://lore.kernel.org/r/20210731120519.17154-1-kumarpraveen@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org> |
||
---|---|---|
.. | ||
boot | ||
configs | ||
crypto | ||
entry | ||
events | ||
hyperv | ||
ia32 | ||
include | ||
kernel | ||
kvm | ||
lib | ||
math-emu | ||
mm | ||
net | ||
pci | ||
platform | ||
power | ||
purgatory | ||
ras | ||
realmode | ||
tools | ||
um | ||
video | ||
xen | ||
.gitignore | ||
Kbuild | ||
Kconfig | ||
Kconfig.assembler | ||
Kconfig.cpu | ||
Kconfig.debug | ||
Makefile | ||
Makefile_32.cpu | ||
Makefile.um |