From: Halil Pasic <pasic@linux.ibm.com>
To: Tony Krowiak <akrowiak@linux.ibm.com>
Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
kvm@vger.kernel.org, jjherne@linux.ibm.com, freude@linux.ibm.com,
borntraeger@de.ibm.com, cohuck@redhat.com,
mjrosato@linux.ibm.com, alex.williamson@redhat.com,
kwankhede@nvidia.com, fiuczy@linux.ibm.com,
frankja@linux.ibm.com, david@redhat.com, hca@linux.ibm.com,
gor@linux.ibm.com
Subject: Re: [PATCH v15 00/13] s390/vfio-ap: dynamic configuration support
Date: Thu, 8 Apr 2021 22:38:04 +0200 [thread overview]
Message-ID: <20210408223804.0ca5ba36.pasic@linux.ibm.com> (raw)
In-Reply-To: <20210406153122.22874-1-akrowiak@linux.ibm.com>
On Tue, 6 Apr 2021 11:31:09 -0400
Tony Krowiak <akrowiak@linux.ibm.com> wrote:
> Tony Krowiak (13):
> s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks
The subsequent patches, re introduce this circular locking dependency
problem. See my kernel messages for the details. The link we severe
in the above patch is re-introduced at several places. One of them is
assign_adapter_store().
Regards,
Halil
[ +0.000236] vfio_ap matrix: MDEV: Registered
[ +0.037919] vfio_mdev 4f77ad87-1e62-4959-8b7a-c677c98d2194: Adding to iommu group 1
[ +0.000092] vfio_mdev 4f77ad87-1e62-4959-8b7a-c677c98d2194: MDEV: group_id = 1
[Apr 8 22:31] ======================================================
[ +0.000002] WARNING: possible circular locking dependency detected
[ +0.000002] 5.12.0-rc6-00016-g5bea90816c56 #57 Not tainted
[ +0.000002] ------------------------------------------------------
[ +0.000002] CPU 1/KVM/6651 is trying to acquire lock:
[ +0.000002] 00000000cef9d508 (&matrix_dev->lock){+.+.}-{3:3}, at: handle_pqap+0x56/0x1c8 [vfio_ap]
[ +0.000011]
but task is already holding lock:
[ +0.000001] 00000000d41f4308 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x90/0x898 [kvm]
[ +0.000038]
which lock already depends on the new lock.
[ +0.000002]
the existing dependency chain (in reverse order) is:
[ +0.000001]
-> #2 (&vcpu->mutex){+.+.}-{3:3}:
[ +0.000004] validate_chain+0x796/0xa20
[ +0.000006] __lock_acquire+0x420/0x7c8
[ +0.000003] lock_acquire.part.0+0xec/0x1e8
[ +0.000002] lock_acquire+0xb8/0x208
[ +0.000002] __mutex_lock+0xa2/0x928
[ +0.000005] mutex_lock_nested+0x32/0x40
[ +0.000002] kvm_s390_cpus_to_pv+0x4e/0xf8 [kvm]
[ +0.000019] kvm_s390_handle_pv+0x1ce/0x6b0 [kvm]
[ +0.000018] kvm_arch_vm_ioctl+0x3ec/0x550 [kvm]
[ +0.000019] kvm_vm_ioctl+0x40e/0x4a8 [kvm]
[ +0.000018] __s390x_sys_ioctl+0xc0/0x100
[ +0.000004] do_syscall+0x7e/0xd0
[ +0.000043] __do_syscall+0xc0/0xd8
[ +0.000004] system_call+0x72/0x98
[ +0.000004]
-> #1 (&kvm->lock){+.+.}-{3:3}:
[ +0.000004] validate_chain+0x796/0xa20
[ +0.000002] __lock_acquire+0x420/0x7c8
[ +0.000002] lock_acquire.part.0+0xec/0x1e8
[ +0.000002] lock_acquire+0xb8/0x208
[ +0.000003] __mutex_lock+0xa2/0x928
[ +0.000002] mutex_lock_nested+0x32/0x40
[ +0.000002] kvm_arch_crypto_set_masks+0x4a/0x2b8 [kvm]
[ +0.000018] vfio_ap_mdev_refresh_apcb+0xd0/0xe0 [vfio_ap]
[ +0.000003] assign_adapter_store+0x1f2/0x240 [vfio_ap]
[ +0.000003] kernfs_fop_write_iter+0x13e/0x1e0
[ +0.000003] new_sync_write+0x10a/0x198
[ +0.000003] vfs_write.part.0+0x196/0x290
[ +0.000002] ksys_write+0x6c/0xf8
[ +0.000003] do_syscall+0x7e/0xd0
[ +0.000002] __do_syscall+0xc0/0xd8
[ +0.000003] system_call+0x72/0x98
[ +0.000002]
-> #0 (&matrix_dev->lock){+.+.}-{3:3}:
[ +0.000004] check_noncircular+0x16e/0x190
[ +0.000002] check_prev_add+0xec/0xf38
[ +0.000002] validate_chain+0x796/0xa20
[ +0.000002] __lock_acquire+0x420/0x7c8
[ +0.000002] lock_acquire.part.0+0xec/0x1e8
[ +0.000002] lock_acquire+0xb8/0x208
[ +0.000002] __mutex_lock+0xa2/0x928
[ +0.000002] mutex_lock_nested+0x32/0x40
[ +0.000003] handle_pqap+0x56/0x1c8 [vfio_ap]
[ +0.000002] handle_pqap+0xe2/0x1d8 [kvm]
[ +0.000019] kvm_handle_sie_intercept+0x134/0x248 [kvm]
[ +0.000019] vcpu_post_run+0x2b6/0x580 [kvm]
[ +0.000018] __vcpu_run+0x27e/0x388 [kvm]
[ +0.000019] kvm_arch_vcpu_ioctl_run+0x10a/0x278 [kvm]
[ +0.000018] kvm_vcpu_ioctl+0x2cc/0x898 [kvm]
[ +0.000018] __s390x_sys_ioctl+0xc0/0x100
[ +0.000003] do_syscall+0x7e/0xd0
[ +0.000002] __do_syscall+0xc0/0xd8
[ +0.000002] system_call+0x72/0x98
[ +0.000003]
other info that might help us debug this:
[ +0.000001] Chain exists of:
&matrix_dev->lock --> &kvm->lock --> &vcpu->mutex
[ +0.000005] Possible unsafe locking scenario:
[ +0.000001] CPU0 CPU1
[ +0.000001] ---- ----
[ +0.000002] lock(&vcpu->mutex);
[ +0.000002] lock(&kvm->lock);
[ +0.000002] lock(&vcpu->mutex);
[ +0.000002] lock(&matrix_dev->lock);
[ +0.000002]
*** DEADLOCK ***
[ +0.000002] 2 locks held by CPU 1/KVM/6651:
[ +0.000002] #0: 00000000d41f4308 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x90/0x898 [kvm]
[ +0.000023] #1: 00000000da2fc508 (&kvm->srcu){....}-{0:0}, at: __vcpu_run+0x1ec/0x388 [kvm]
[ +0.000021]
stack backtrace:
[ +0.000002] CPU: 6 PID: 6651 Comm: CPU 1/KVM Not tainted 5.12.0-rc6-00016-g5bea90816c56 #57
[ +0.000004] Hardware name: IBM 8561 T01 701 (LPAR)
[ +0.000001] Call Trace:
[ +0.000002] [<00000002010e7ef0>] show_stack+0x90/0xf8
[ +0.000007] [<00000002010fb5b2>] dump_stack+0xba/0x108
[ +0.000002] [<000000020053feb6>] check_noncircular+0x16e/0x190
[ +0.000003] [<0000000200541424>] check_prev_add+0xec/0xf38
[ +0.000002] [<0000000200542a06>] validate_chain+0x796/0xa20
[ +0.000003] [<0000000200545430>] __lock_acquire+0x420/0x7c8
[ +0.000002] [<00000002005441a4>] lock_acquire.part.0+0xec/0x1e8
[ +0.000002] [<0000000200544358>] lock_acquire+0xb8/0x208
[ +0.000003] [<000000020110aeea>] __mutex_lock+0xa2/0x928
[ +0.000002] [<000000020110b7a2>] mutex_lock_nested+0x32/0x40
[ +0.000003] [<000003ff8060fb5e>] handle_pqap+0x56/0x1c8 [vfio_ap]
[ +0.000003] [<000003ff80597412>] handle_pqap+0xe2/0x1d8 [kvm]
[ +0.000018] [<000003ff8058c924>] kvm_handle_sie_intercept+0x134/0x248 [kvm]
[ +0.000020] [<000003ff80588e96>] vcpu_post_run+0x2b6/0x580 [kvm]
[ +0.000019] [<000003ff805893de>] __vcpu_run+0x27e/0x388 [kvm]
[ +0.000018] [<000003ff80589d0a>] kvm_arch_vcpu_ioctl_run+0x10a/0x278 [kvm]
[ +0.000019] [<000003ff805704d4>] kvm_vcpu_ioctl+0x2cc/0x898 [kvm]
[ +0.000019] [<0000000200801ee8>] __s390x_sys_ioctl+0xc0/0x100
[ +0.000003] [<000000020046e7ae>] do_syscall+0x7e/0xd0
[ +0.000003] [<00000002010ffc20>] __do_syscall+0xc0/0xd8
[ +0.000002] [<0000000201110c42>] system_call+0x72/0x98
[ +0.000003] INFO: lockdep is turned off.
[ +6.846296] vfio_mdev 4f77ad87-1e62-4959-8b7a-c677c98d2194: Removing from iommu group 1
[ +0.000028] vfio_mdev 4f77ad87-1e62-4959-8b7a-c677c98d2194: MDEV: detaching iommu
[ +0.007677] vfio_ap matrix: MDEV: Unregistering
> s390/vfio-ap: use new AP bus interface to search for queue devices
> s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.c
> s390/vfio-ap: manage link between queue struct and matrix mdev
> s390/vfio-ap: introduce shadow APCB
> s390/vfio-ap: refresh guest's APCB by filtering APQNs assigned to mdev
> s390/vfio-ap: allow assignment of unavailable AP queues to mdev device
> s390/vfio-ap: allow hot plug/unplug of AP resources using mdev device
> s390/zcrypt: driver callback to indicate resource in use
> s390/vfio-ap: implement in-use callback for vfio_ap driver
> s390/vfio-ap: sysfs attribute to display the guest's matrix
> s390/zcrypt: notify drivers on config changed and scan complete
> callbacks
> s390/vfio-ap: update docs to include dynamic config support
next prev parent reply other threads:[~2021-04-08 20:38 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-06 15:31 [PATCH v15 00/13] s390/vfio-ap: dynamic configuration support Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 01/13] s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 02/13] s390/vfio-ap: use new AP bus interface to search for queue devices Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 03/13] s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.c Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 04/13] s390/vfio-ap: manage link between queue struct and matrix mdev Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 05/13] s390/vfio-ap: introduce shadow APCB Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 06/13] s390/vfio-ap: refresh guest's APCB by filtering APQNs assigned to mdev Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 07/13] s390/vfio-ap: allow assignment of unavailable AP queues to mdev device Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 08/13] s390/vfio-ap: allow hot plug/unplug of AP resources using " Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 09/13] s390/zcrypt: driver callback to indicate resource in use Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 10/13] s390/vfio-ap: implement in-use callback for vfio_ap driver Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 11/13] s390/vfio-ap: sysfs attribute to display the guest's matrix Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 12/13] s390/zcrypt: notify drivers on config changed and scan complete callbacks Tony Krowiak
2021-04-06 15:31 ` [PATCH v15 13/13] s390/vfio-ap: update docs to include dynamic config support Tony Krowiak
2021-04-08 20:38 ` Halil Pasic [this message]
2021-04-09 13:26 ` [PATCH v15 00/13] s390/vfio-ap: dynamic configuration support Tony Krowiak
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210408223804.0ca5ba36.pasic@linux.ibm.com \
--to=pasic@linux.ibm.com \
--cc=akrowiak@linux.ibm.com \
--cc=alex.williamson@redhat.com \
--cc=borntraeger@de.ibm.com \
--cc=cohuck@redhat.com \
--cc=david@redhat.com \
--cc=fiuczy@linux.ibm.com \
--cc=frankja@linux.ibm.com \
--cc=freude@linux.ibm.com \
--cc=gor@linux.ibm.com \
--cc=hca@linux.ibm.com \
--cc=jjherne@linux.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=kwankhede@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=mjrosato@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.