linux_dsm_epyc7002/include
Dmitry Safonov effa467870 iommu/vt-d: Don't queue_iova() if there is no flush queue
Intel VT-d driver was reworked to use common deferred flushing
implementation. Previously there was one global per-cpu flush queue,
afterwards - one per domain.

Before deferring a flush, the queue should be allocated and initialized.

Currently only domains with IOMMU_DOMAIN_DMA type initialize their flush
queue. It's probably worth to init it for static or unmanaged domains
too, but it may be arguable - I'm leaving it to iommu folks.

Prevent queuing an iova flush if the domain doesn't have a queue.
The defensive check seems to be worth to keep even if queue would be
initialized for all kinds of domains. And is easy backportable.

On 4.19.43 stable kernel it has a user-visible effect: previously for
devices in si domain there were crashes, on sata devices:

 BUG: spinlock bad magic on CPU#6, swapper/0/1
  lock: 0xffff88844f582008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
 CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #1
 Call Trace:
  <IRQ>
  dump_stack+0x61/0x7e
  spin_bug+0x9d/0xa3
  do_raw_spin_lock+0x22/0x8e
  _raw_spin_lock_irqsave+0x32/0x3a
  queue_iova+0x45/0x115
  intel_unmap+0x107/0x113
  intel_unmap_sg+0x6b/0x76
  __ata_qc_complete+0x7f/0x103
  ata_qc_complete+0x9b/0x26a
  ata_qc_complete_multiple+0xd0/0xe3
  ahci_handle_port_interrupt+0x3ee/0x48a
  ahci_handle_port_intr+0x73/0xa9
  ahci_single_level_irq_intr+0x40/0x60
  __handle_irq_event_percpu+0x7f/0x19a
  handle_irq_event_percpu+0x32/0x72
  handle_irq_event+0x38/0x56
  handle_edge_irq+0x102/0x121
  handle_irq+0x147/0x15c
  do_IRQ+0x66/0xf2
  common_interrupt+0xf/0xf
 RIP: 0010:__do_softirq+0x8c/0x2df

The same for usb devices that use ehci-pci:
 BUG: spinlock bad magic on CPU#0, swapper/0/1
  lock: 0xffff88844f402008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #4
 Call Trace:
  <IRQ>
  dump_stack+0x61/0x7e
  spin_bug+0x9d/0xa3
  do_raw_spin_lock+0x22/0x8e
  _raw_spin_lock_irqsave+0x32/0x3a
  queue_iova+0x77/0x145
  intel_unmap+0x107/0x113
  intel_unmap_page+0xe/0x10
  usb_hcd_unmap_urb_setup_for_dma+0x53/0x9d
  usb_hcd_unmap_urb_for_dma+0x17/0x100
  unmap_urb_for_dma+0x22/0x24
  __usb_hcd_giveback_urb+0x51/0xc3
  usb_giveback_urb_bh+0x97/0xde
  tasklet_action_common.isra.4+0x5f/0xa1
  tasklet_action+0x2d/0x30
  __do_softirq+0x138/0x2df
  irq_exit+0x7d/0x8b
  smp_apic_timer_interrupt+0x10f/0x151
  apic_timer_interrupt+0xf/0x20
  </IRQ>
 RIP: 0010:_raw_spin_unlock_irqrestore+0x17/0x39

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: <stable@vger.kernel.org> # 4.14+
Fixes: 13cf017446 ("iommu/vt-d: Make use of iova deferred flushing")
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:43:06 +02:00
..
acpi
asm-generic Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2019-07-17 13:13:41 -07:00
clocksource
crypto
drm drm fixes for -rc1: 2019-07-19 12:29:43 -07:00
dt-bindings ARM: Device-tree updates 2019-07-19 17:19:24 -07:00
keys
kvm
linux iommu/vt-d: Don't queue_iova() if there is no flush queue 2019-07-22 17:43:06 +02:00
math-emu
media
misc powerpc updates for 5.3 2019-07-13 16:08:36 -07:00
net tcp: fix tcp_set_congestion_control() use from bpf hook 2019-07-18 20:33:48 -07:00
pcmcia
ras
rdma
scsi SCSI fixes on 20190720 2019-07-20 10:04:58 -07:00
soc ARM: SoC-related driver updates 2019-07-19 17:13:56 -07:00
sound ALSA: hda - Don't resume forcibly i915 HDMI/DP codec 2019-07-16 22:46:13 +02:00
target
trace NFS client updates for Linux 5.3 2019-07-18 14:32:33 -07:00
uapi drm fixes for -rc1: 2019-07-19 12:29:43 -07:00
vdso
video drm main pull request for v5.3-rc1 (sans mm changes) 2019-07-15 19:04:27 -07:00
xen xen: remove tmem driver 2019-07-17 08:09:58 +02:00
Kbuild kbuild: update compile-test header list for v5.3-rc1 2019-07-20 11:19:29 +09:00