Hello,

I compiled the RC5 of kernel 5.11 today. Unfortunately KVM HV doesn't 
work anymore on my FSL P5040 board [1]. I tested it with QEMU 5.0.0 
today [2]. The virtual e5500 QEMU machine works with the "RC4 with KVM 
HV" and with the "RC5 without KVM HV". The complete system freezes if I 
use KVM HV with the RC5.

I have bisected and 785025820a6a565185ce9d47fdd8d23dbf91dee8 
(powerpc/mm/highmem: use __set_pte_at() for kmap_local()) [3] is the 
first bad commit.

I was able to revert this bad commit and after a new compiling, KVM HV 
works again.  I created a patch for reverting the commit. [4] Please 
find attached the kernel config. I use one uImage for the virtual 
machine and for the P5040 board.

Please check the first bad commit.

Thanks,
Christian


[1] http://wiki.amiga.org/index.php?title=X5000
[2] qemu-system-ppc64 -M ppce500 -cpu e5500 -enable-kvm -m 1024 -kernel 
uImage-5.11 -drive format=raw,file=MintPPC32-X5000.img,index=0,if=virtio 
-netdev user,id=mynet0 -device e1000,netdev=mynet0 -append "rw 
root=/dev/vda" -device virtio-vga -device virtio-mouse-pci -device 
virtio-keyboard-pci -device pci-ohci,id=newusb -device 
usb-audio,bus=newusb.0 -smp 4
[3] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.11-rc5&id=785025820a6a565185ce9d47fdd8d23dbf91dee8
[4]
diff -rupN a/arch/powerpc/include/asm/highmem.h 
b/arch/powerpc/include/asm/highmem.h

--- a/arch/powerpc/include/asm/highmem.h        2021-01-27 

16:12:40.382164118 +0100

+++ b/arch/powerpc/include/asm/highmem.h        2021-01-27 

16:10:54.055249957 +0100

@@ -58,8 +58,6 @@ extern pte_t *pkmap_page_table;

  #define flush_cache_kmaps()    flush_cache_all()

-#define arch_kmap_local_set_pte(mm, vaddr, ptep, ptev) \
-       __set_pte_at(mm, vaddr, ptep, ptev, 1)
  #define arch_kmap_local_post_map(vaddr, pteval)        \
         local_flush_tlb_page(NULL, vaddr)
  #define arch_kmap_local_post_unmap(vaddr)      \