Re: [PULL 2/7] s390x: do a subsystem reset before the unprotect on reboot

[Matthew Rosato <mjrosato@linux.ibm.com>]

On 1/11/24 5:18 AM, Christian Borntraeger wrote:
> 
> 
> Am 11.01.24 um 10:43 schrieb Cédric Le Goater:
> [...]
>>
>>
>> On a side note, I am also seeing :
> 
> Michael?
> 

Hmm, it looks like this warning is tripping because we have a path in PCI passthrough where we don't unregister the gisc.  This warning notices that at the time we destroy the VM (it believes that are still consumers of the guest ISC so the bit in the alert mask is still on) -- after cutting the warning the code forces the alerts off at least.

Not sure yet if that is directly related to the device going into error condition or if it is an independent issue, will have a look.

>>
>> [   73.989688] ------------[ cut here ]------------
>> [   73.989696] unexpected non zero alert.mask 0x20
>> [   73.989748] WARNING: CPU: 9 PID: 4503 at arch/s390/kvm/interrupt.c:3214 kvm_s390_gisa_destroy+0xd4/0xe8 [kvm]
>> [   73.989791] Modules linked in: vfio_pci vfio_pci_core irqbypass vhost_net vhost vhost_iotlb tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink 8021q garp mrp rfkill sunrpc ext4 mbcache jbd2 vfio_ap zcrypt_cex4 vfio_ccw mdev vfio_iommu_type1 vfio drm fuse i2c_core drm_panel_orientation_quirks xfs libcrc32c dm_service_time mlx5_core sd_mod t10_pi ghash_s390 sg prng des_s390 libdes sha3_512_s390 sha3_256_s390 mlxfw tls scm_block psample eadm_sch qeth_l2 bridge stp llc dasd_eckd_mod zfcp qeth dasd_mod scsi_transport_fc ccwgroup qdio dm_multipath dm_mirror dm_region_hash dm_log dm_mod pkey zcrypt kvm aes_s390
>> [   73.989825] CPU: 9 PID: 4503 Comm: worker Kdump: loaded Not tainted 6.7.0-clg-dirty #52
>> [   73.989827] Hardware name: IBM 3931 LA1 400 (LPAR)
>> [   73.989829] Krnl PSW : 0704c00180000000 000003ff7fcd2198 (kvm_s390_gisa_destroy+0xd8/0xe8 [kvm])
>> [   73.989845]            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
>> [   73.989847] Krnl GPRS: c0000000fffeffff 0000000700000027 0000000000000023 00000007df4249c8
>> [   73.989849]            000003800649b858 000003800649b850 00000007fcb9db00 0000000000000000
>> [   73.989851]            000000008ebae8c8 0000000083a8c4f0 0000000000b69900 000000008ebac000
>> [   73.989853]            000003ff903aef68 000003800649bd98 000003ff7fcd2194 000003800649b9f8
>> [   73.989859] Krnl Code: 000003ff7fcd2188: c02000024f88    larl    %r2,000003ff7fd1c098
>>                            000003ff7fcd218e: c0e5fffea360    brasl    %r14,000003ff7fca684e
>>                           #000003ff7fcd2194: af000000        mc    0,0
>>                           >000003ff7fcd2198: e310b7680204    lg    %r1,10088(%r11)
>>                            000003ff7fcd219e: a7f4ffae        brc    15,000003ff7fcd20fa
>>                            000003ff7fcd21a2: 0707        bcr    0,%r7
>>                            000003ff7fcd21a4: 0707        bcr    0,%r7
>>                            000003ff7fcd21a6: 0707        bcr    0,%r7
>> [   73.989929] Call Trace:
>> [   73.989931]  [<000003ff7fcd2198>] kvm_s390_gisa_destroy+0xd8/0xe8 [kvm]
>> [   73.989946] ([<000003ff7fcd2194>] kvm_s390_gisa_destroy+0xd4/0xe8 [kvm])
>> [   73.989960]  [<000003ff7fcc1578>] kvm_arch_destroy_vm+0x50/0x118 [kvm]
>> [   73.989974]  [<000003ff7fcb00a2>] kvm_destroy_vm+0x15a/0x260 [kvm]
>> [   73.989985]  [<000003ff7fcb021e>] kvm_vm_release+0x36/0x48 [kvm]
>> [   73.989996]  [<00000007de4f830c>] __fput+0x94/0x2d0
>> [   73.990009]  [<00000007de20d838>] task_work_run+0x88/0xe8
>> [   73.990013]  [<00000007de1e75e0>] do_exit+0x2e0/0x4e0
>> [   73.990016]  [<00000007de1e79c0>] do_group_exit+0x40/0xb8
>> [   73.990017]  [<00000007de1f96e8>] send_sig_info+0x0/0xa8
>> [   73.990021]  [<00000007de194b26>] arch_do_signal_or_restart+0x56/0x318
>> [   73.990025]  [<00000007de28bf12>] exit_to_user_mode_prepare+0x10a/0x1a0
>> [   73.990028]  [<00000007deb607d2>] __do_syscall+0x152/0x1f8
>> [   73.990032]  [<00000007deb70ac8>] system_call+0x70/0x98
>> [   73.990036] Last Breaking-Event-Address:
>> [   73.990037]  [<00000007de1e0c58>] __warn_printk+0x78/0xe8
>>
>>