Created attachment 288869 [details]
dmesg part including call trace

Hi,

after upgrading the Kernel from 5.4.x to any 5.6.x or even a current RC-kernel of the 5.7 series, I'm unable to start a KVM-based virtual machine. Shortly after passing the ed2k-firmware boot stage the VM hangs and the kernel outputs (see attached file for extended log output):

[   85.108980] BUG: stack guard page was hit at 0000000058db6ab1 (stack is 0000000033777485..00000000bcf1c827)
[   85.118710] kernel stack overflow (double-fault): 0000 [#1] SMP NOPTI
[   85.125141] CPU: 0 PID: 1843 Comm: qemu-system-x86 Not tainted 5.6.8 #1
[   85.131745] Hardware name: ASUS All Series/X99-E WS/USB 3.1, BIOS 3803 06/26/2018
[   85.139238] RIP: 0010:pic_update_irq+0x5/0x70 [kvm]
[   85.144111] Code: e2 fb 48 83 c2 18 48 39 d7 45 0f 44 c2 eb ae 31 f6 eb 9f 31 d2 eb cf 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 0f 1f 44 00 00 <53> 48 89 fb 48 83 c7 38 e8 2e ff ff ff 85 c0 79 29 48 8d 7b 18 e8
[   85.162848] RSP: 0018:ffffc90001dd8000 EFLAGS: 00010246
[   85.168066] RAX: 0000000000000020 RBX: 0000000000000000 RCX: 0000000000000020
[   85.175188] RDX: 00000000000000ff RSI: 0000000000000020 RDI: ffff88881a0bf300
[   85.182313] RBP: 0000000000000005 R08: ffffc90001bad000 R09: ffff88883927e000
[   85.189437] R10: 0000000000000000 R11: ffff888815f50000 R12: 00000000ffffffff
[   85.196561] R13: 0000000000000000 R14: 0000000000000000 R15: ffff88881a0bf300
[   85.203688] FS:  00007ffa9582bc40(0000) GS:ffff88884fa00000(0000) knlGS:0000000000000000
[   85.211762] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   85.217501] CR2: ffffc90001dd7ff8 CR3: 0000000805b1e002 CR4: 00000000001626f0

This issue is reproducible. I've skipped kernel 5.5 entirely.