Linux 5.19-rc7: WARNING: CPU: 5 PID: 50 at drivers/block/xen-blkback/xenbus.c:322 xen_blkif_disconnect+0x24f/0x260

[Sander Eikelenboom <linux@xxxxxxxxxxxxxx>]

Hi Juergen,


While trying out linux-5.19-rc7 (both for dom0 and domU's) running under 
Xen, I encounter these warnings below for every domU in my kernel log on 
dom0. The domU's don't boot any further because of lacking a block device.
Normally I use the same kernel for both dom0 and domU while booting with
direct kernel boot,

I also tried the combination of a 5.19-rc7 dom0 kernel and 5.18 domU 
kernel and then no warnings and all domU's boot fine.
Any ideas ?

--
Sander



[  144.137781] ------------[ cut here ]------------
[  144.137782] WARNING: CPU: 5 PID: 50 at 
drivers/block/xen-blkback/xenbus.c:322 xen_blkif_disconnect+0x24f/0x260
[  144.137786] Modules linked in:
[  144.137787] CPU: 5 PID: 50 Comm: xenwatch Tainted: G        W 
5.19.0-rc7-20220722-doflr-mac80211debug+ #1
[  144.137789] Hardware name: MSI MS-7640/890FXA-GD70 (MS-7640)  , BIOS 
V1.8B1 09/13/2010
[  144.137791] RIP: e030:xen_blkif_disconnect+0x24f/0x260
[  144.137794] Code: 20 48 8d 56 20 48 8d 48 e0 48 3b 54 24 08 0f 84 a7 
fe ff ff 4c 8b 74 24 10 48 89 4c 24 10 eb 82 0f 0b 0f 0b 0f 0b 0f 0b 0f 
0b <0f> 0b e9 ef fe ff ff b8 f0 ff ff ff e9 34 ff ff ff 41 54 55 48 89
[  144.137795] RSP: e02b:ffffc90000847dd8 EFLAGS: 00010202
[  144.137797] RAX: 0000000000000040 RBX: 0000000000000001 RCX: 
ffff88800fef8350
[  144.137799] RDX: 0000000000000000 RSI: 0000000000000200 RDI: 
00000000ffffffff
[  144.137800] RBP: ffff88800fef82f0 R08: ffff88807d36fd00 R09: 
0000000000028220
[  144.137802] R10: 000000000002fd60 R11: 0000000000000006 R12: 
0000000000000002
[  144.137803] R13: ffff88801d1cd000 R14: ffff88800fef8330 R15: 
ffff888006c70cc0
[  144.137807] FS:  0000000000000000(0000) GS:ffff88807d340000(0000) 
knlGS:0000000000000000
[  144.137809] CS:  e030 DS: 0000 ES: 0000 CR0: 0000000080050033
[  144.137810] CR2: 00007f536f443450 CR3: 0000000023000000 CR4: 
0000000000000660
[  144.137813] Call Trace:
[  144.137814]  <TASK>
[  144.137816]  frontend_changed+0x388/0x450
[  144.137819]  xenwatch_thread+0x9c/0x170
[  144.137822]  ? cpu_core_flags+0x10/0x10
[  144.137824]  ? find_watch+0x50/0x50
[  144.137827]  kthread+0xe3/0x110
[  144.137830]  ? kthread_complete_and_exit+0x20/0x20
[  144.137832]  ret_from_fork+0x22/0x30
[  144.137835]  </TASK>
[  144.137836] ---[ end trace 0000000000000000 ]---