Commit Graph

713 Commits

Author SHA1 Message Date
Juergen Gross
3f9dfbebdc virtio: replace arch_has_restricted_virtio_memory_access()
Instead of using arch_has_restricted_virtio_memory_access() together
with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those
with platform_has() and a new platform feature
PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 only
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Borislav Petkov <bp@suse.de>
2022-06-06 08:22:01 +02:00
keliu
4f58afd6eb virtio: Directly use ida_alloc()/free()
Use ida_alloc()/ida_free() instead of deprecated
ida_simple_get()/ida_simple_remove() .

Signed-off-by: keliu <liuke94@huawei.com>
Message-Id: <20220527073302.2474073-1-liuke94@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:45:10 -04:00
Jason Wang
8b4ec69d7e virtio: harden vring IRQ
This is a rework on the previous IRQ hardening that is done for
virtio-pci where several drawbacks were found and were reverted:

1) try to use IRQF_NO_AUTOEN which is not friendly to affinity managed IRQ
   that is used by some device such as virtio-blk
2) done only for PCI transport

The vq->broken is re-used in this patch for implementing the IRQ
hardening. The vq->broken is set to true during both initialization
and reset. And the vq->broken is set to false in
virtio_device_ready(). Then vring_interrupt() can check and return
when vq->broken is true. And in this case, switch to return IRQ_NONE
to let the interrupt core aware of such invalid interrupt to prevent
IRQ storm.

The reason of using a per queue variable instead of a per device one
is that we may need it for per queue reset hardening in the future.

Note that the hardening is only done for vring interrupt since the
config interrupt hardening is already done in commit 22b7050a02
("virtio: defer config changed notifications"). But the method that is
used by config interrupt can't be reused by the vring interrupt
handler because it uses spinlock to do the synchronization which is
expensive.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-9-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
2022-05-31 12:45:10 -04:00
Jason Wang
be83f04d25 virtio: allow to unbreak virtqueue
This patch allows the new introduced __virtio_break_device() to
unbreak the virtqueue.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-8-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
2022-05-31 12:45:10 -04:00
Jason Wang
9e9b289328 virtio-mmio: implement synchronize_cbs()
Simply synchronize the platform irq that is used by us.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-6-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
2022-05-31 12:45:09 -04:00
Jason Wang
48b3dd2438 virtio-pci: implement synchronize_cbs()
We can simply reuse vp_synchronize_vectors() for .synchronize_cbs().

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-5-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
2022-05-31 12:45:09 -04:00
Jason Wang
0aa96837c3 virtio: use virtio_reset_device() when possible
This allows us to do common extension without duplicating code.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-3-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
2022-05-31 12:45:09 -04:00
Stefano Garzarella
2536b2ca15 virtio: use virtio_device_ready() in virtio_device_restore()
It will allow us to do extension on virtio_device_ready() without
duplicating code.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-2-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
2022-05-31 12:45:09 -04:00
Solomon Tan
0619eda83d virtio: Replace long long int with long long
This patch addresses the checkpatch.pl warning that long long is
preferred over long long int.

Signed-off-by: Solomon Tan <solomonbstoner@protonmail.ch>
Message-Id: <YlzTUQa06sP94zxB@ArchDesktop>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:45:09 -04:00
Solomon Tan
3153234097 virtio: Replace unsigned with unsigned int
This patch addresses the checkpatch.pl warning where unsigned int is
preferred over unsigned.

Signed-off-by: Solomon Tan <solomonbstoner@protonmail.ch>
Message-Id: <YlzS49Wo8JMDhKOt@ArchDesktop>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:45:09 -04:00
Murilo Opsfelder Araujo
7e415282b4 virtio-pci: Remove wrong address verification in vp_del_vqs()
GCC 12 enhanced -Waddress when comparing array address to null [0],
which warns:

    drivers/virtio/virtio_pci_common.c: In function ‘vp_del_vqs’:
    drivers/virtio/virtio_pci_common.c:257:29: warning: the comparison will always evaluate as ‘true’ for the pointer operand in ‘vp_dev->msix_affinity_masks + (sizetype)((long unsigned int)i * 256)’ must not be NULL [-Waddress]
      257 |                         if (vp_dev->msix_affinity_masks[i])
          |                             ^~~~~~

In fact, the verification is comparing the result of a pointer
arithmetic, the address "msix_affinity_masks + i", which will always
evaluate to true.

Under the hood, free_cpumask_var() calls kfree(), which is safe to pass
NULL, not requiring non-null verification.  So remove the verification
to make compiler happy (happy compiler, happy life).

[0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102103

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Message-Id: <20220415023002.49805-1-muriloo@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Christophe de Dinechin <dinechin@redhat.com>
2022-05-31 12:45:08 -04:00
Christophe JAILLET
7a836a2aba virtio: pci: Fix an error handling path in vp_modern_probe()
If an error occurs after a successful pci_request_selected_regions() call,
it should be undone by a corresponding pci_release_selected_regions() call,
as already done in vp_modern_remove().

Fixes: fd502729fb ("virtio-pci: introduce modern device module")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Message-Id: <237109725aad2c3c03d14549f777b1927c84b045.1648977064.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:45:08 -04:00
Gautam Dawar
ea239a6746 virtio-vdpa: don't set callback if virtio doesn't need it
There's no need for setting callbacks for the driver that doesn't care
about that.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-3-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:44:26 -04:00
Xianting Tian
b4b4ff73ef virtio_ring: add unlikely annotation for free descs check
The 'if (vq->vq.num_free < descs_used)' check will almost always be false.

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Message-Id: <20220328105817.1028065-2-xianting.tian@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2022-05-31 12:44:25 -04:00
Xianting Tian
35c51e093d virtio_ring: remove unnecessary to_vvq call in vring hot path
It passes '_vq' to virtqueue_use_indirect(), which still calls
to_vvq to get 'vq', let's directly pass 'vq'. It can avoid
unnecessary call of to_vvq in hot path.

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Message-Id: <20220328105817.1028065-1-xianting.tian@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2022-05-31 12:44:24 -04:00
Zi Yan
448b8ec3bf drivers: virtio_mem: use pageblock size as the minimum virtio_mem size.
alloc_contig_range() now only needs to be aligned to pageblock_nr_pages,
drop virtio_mem size requirement that it needs to be MAX_ORDER_NR_PAGES.

Link: https://lkml.kernel.org/r/20220425143118.2850746-7-zi.yan@sent.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric Ren <renzhengeek@gmail.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 07:20:13 -07:00
Linus Torvalds
3e732ebf73 virtio: fixes, cleanups
A couple of mlx5 fixes related to cvq
 A couple of reverts dropping useless code (code that used it got reverted
 earlier)
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael Tsirkin:
 "Fixes and cleanups:

   - A couple of mlx5 fixes related to cvq

   - A couple of reverts dropping useless code (code that used it got
     reverted earlier)"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vdpa: mlx5: synchronize driver status with CVQ
  vdpa: mlx5: prevent cvq work from hogging CPU
  Revert "virtio_config: introduce a new .enable_cbs method"
  Revert "virtio: use virtio_device_ready() in virtio_device_restore()"
2022-04-05 10:40:52 -07:00
Linus Torvalds
f4f5d7cfb2 virtio: features, fixes
vdpa generic device type support
 More virtio hardening for broken devices
 On the same theme, revert some virtio hotplug hardening patches -
 they were misusing some interrupt flags, will have to be reverted.
 RSS support in virtio-net
 max device MTU support in mlx5 vdpa
 akcipher support in virtio-crypto
 shared IRQ support in ifcvf vdpa
 a minor performance improvement in vhost
 Enable virtio mem for ARM64
 beginnings of advance dma support
 
 Cleanups, fixes all over the place.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

 - vdpa generic device type support

 - more virtio hardening for broken devices (but on the same theme,
   revert some virtio hotplug hardening patches - they were misusing
   some interrupt flags and had to be reverted)

 - RSS support in virtio-net

 - max device MTU support in mlx5 vdpa

 - akcipher support in virtio-crypto

 - shared IRQ support in ifcvf vdpa

 - a minor performance improvement in vhost

 - enable virtio mem for ARM64

 - beginnings of advance dma support

 - cleanups, fixes all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (33 commits)
  vdpa/mlx5: Avoid processing works if workqueue was destroyed
  vhost: handle error while adding split ranges to iotlb
  vdpa: support exposing the count of vqs to userspace
  vdpa: change the type of nvqs to u32
  vdpa: support exposing the config size to userspace
  vdpa/mlx5: re-create forwarding rules after mac modified
  virtio: pci: check bar values read from virtio config space
  Revert "virtio_pci: harden MSI-X interrupts"
  Revert "virtio-pci: harden INTX interrupts"
  drivers/net/virtio_net: Added RSS hash report control.
  drivers/net/virtio_net: Added RSS hash report.
  drivers/net/virtio_net: Added basic RSS support.
  drivers/net/virtio_net: Fixed padded vheader to use v1 with hash.
  virtio: use virtio_device_ready() in virtio_device_restore()
  tools/virtio: compile with -pthread
  tools/virtio: fix after premapped buf support
  virtio_ring: remove flags check for unmap packed indirect desc
  virtio_ring: remove flags check for unmap split indirect desc
  virtio_ring: rename vring_unmap_state_packed() to vring_unmap_extra_packed()
  net/mlx5: Add support for configuring max device MTU
  ...
2022-03-31 13:57:15 -07:00
Michael S. Tsirkin
7414539c5f Revert "virtio: use virtio_device_ready() in virtio_device_restore()"
This reverts commit 8d65bc9a5b.

We reverted the problematic changes, no more need for work
arounds on restore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2022-03-30 04:18:14 -04:00
Keir Fraser
3f63a1d7f6 virtio: pci: check bar values read from virtio config space
virtio pci config structures may in future have non-standard bar
values in the bar field. We should anticipate this by skipping any
structures containing such a reserved value.

The bar value should never change: check for harmful modified values
we re-read it from the config space in vp_modern_map_capability().

Also clean up an existing check to consistently use PCI_STD_NUM_BARS.

Signed-off-by: Keir Fraser <keirf@google.com>
Link: https://lore.kernel.org/r/20220323140727.3499235-1-keirf@google.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:59 -04:00
Jason Wang
eb4cecb453 Revert "virtio_pci: harden MSI-X interrupts"
This reverts commit 9e35276a53. Issue
were reported for the drivers that are using affinity managed IRQ
where manually toggling IRQ status is not expected. And we forget to
enable the interrupts in the restore path as well.

In the future, we will rework on the interrupt hardening.

Fixes: 9e35276a53 ("virtio_pci: harden MSI-X interrupts")
Reported-by: Marc Zyngier <maz@kernel.org>
Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220323031524.6555-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:59 -04:00
Jason Wang
7b79edfb86 Revert "virtio-pci: harden INTX interrupts"
This reverts commit 080cd7c3ac. Since
the MSI-X interrupts hardening will be reverted in the next patch. We
will rework the interrupt hardening in the future.

Fixes: 080cd7c3ac ("virtio-pci: harden INTX interrupts")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220323031524.6555-1-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:59 -04:00
Stefano Garzarella
8d65bc9a5b virtio: use virtio_device_ready() in virtio_device_restore()
After waking up a suspended VM, the kernel prints the following trace
for virtio drivers which do not directly call virtio_device_ready() in
the .restore:

    PM: suspend exit
    irq 22: nobody cared (try booting with the "irqpoll" option)
    Call Trace:
     <IRQ>
     dump_stack_lvl+0x38/0x49
     dump_stack+0x10/0x12
     __report_bad_irq+0x3a/0xaf
     note_interrupt.cold+0xb/0x60
     handle_irq_event+0x71/0x80
     handle_fasteoi_irq+0x95/0x1e0
     __common_interrupt+0x6b/0x110
     common_interrupt+0x63/0xe0
     asm_common_interrupt+0x1e/0x40
     ? __do_softirq+0x75/0x2f3
     irq_exit_rcu+0x93/0xe0
     sysvec_apic_timer_interrupt+0xac/0xd0
     </IRQ>
     <TASK>
     asm_sysvec_apic_timer_interrupt+0x12/0x20
     arch_cpu_idle+0x12/0x20
     default_idle_call+0x39/0xf0
     do_idle+0x1b5/0x210
     cpu_startup_entry+0x20/0x30
     start_secondary+0xf3/0x100
     secondary_startup_64_no_verify+0xc3/0xcb
     </TASK>
    handlers:
    [<000000008f9bac49>] vp_interrupt
    [<000000008f9bac49>] vp_interrupt
    Disabling IRQ #22

This happens because we don't invoke .enable_cbs callback in
virtio_device_restore(). That callback is used by some transports
(e.g. virtio-pci) to enable interrupts.

Let's fix it, by calling virtio_device_ready() as we do in
virtio_dev_probe(). This function calls .enable_cts callback and sets
DRIVER_OK status bit.

This fix also avoids setting DRIVER_OK twice for those drivers that
call virtio_device_ready() in the .restore.

Fixes: d50497eb4e ("virtio_config: introduce a new .enable_cbs method")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20220322114313.116516-1-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:59 -04:00
Xuan Zhuo
920379a465 virtio_ring: remove flags check for unmap packed indirect desc
When calling vring_unmap_desc_packed(), it will not encounter the
situation that the flags contains VRING_DESC_F_INDIRECT. So remove this
logic.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220224110402.108161-4-xuanzhuo@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:58 -04:00
Xuan Zhuo
b4282ebc71 virtio_ring: remove flags check for unmap split indirect desc
When calling vring_unmap_one_split_indirect(), it will not encounter the
situation that the flags contains VRING_DESC_F_INDIRECT. So remove this
logic.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220224110402.108161-3-xuanzhuo@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:58 -04:00
Xuan Zhuo
d80dc15bb6 virtio_ring: rename vring_unmap_state_packed() to vring_unmap_extra_packed()
The actual parameter handled by vring_unmap_state_packed() is that
vring_desc_extra, so this function should use "extra" instead of "state".

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220224110402.108161-2-xuanzhuo@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:58 -04:00
Gavin Shan
6f4abbaa1b drivers/virtio: Enable virtio mem for ARM64
This enables virtio-mem device support by allowing to enable the
corresponding kernel config option (CONFIG_VIRTIO_MEM) on the
architecture.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20220119010551.181405-1-gshan@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-28 16:52:57 -04:00
David Hildenbrand
b3d40a2b6d mm: enforce pageblock_order < MAX_ORDER
Some places in the kernel don't really expect pageblock_order >=
MAX_ORDER, and it looks like this is only possible in corner cases:

1) CONFIG_DEFERRED_STRUCT_PAGE_INIT we'll end up freeing pageblock_order
   pages via __free_pages_core(), which cannot possibly work.

2) find_zone_movable_pfns_for_nodes() will roundup the ZONE_MOVABLE
   start PFN to MAX_ORDER_NR_PAGES. Consequently with a bigger
   pageblock_order, we could have a single pageblock partially managed by
   two zones.

3) compaction code runs into __fragmentation_index() with order
   >= MAX_ORDER, when checking WARN_ON_ONCE(order >= MAX_ORDER). [1]

4) mm/page_reporting.c won't be reporting any pages with default
   page_reporting_order == pageblock_order, as we'll be skipping the
   reporting loop inside page_reporting_process_zone().

5) __rmqueue_fallback() will never be able to steal with
   ALLOC_NOFRAGMENT.

pageblock_order >= MAX_ORDER is weird either way: it's a pure
optimization for making alloc_contig_range(), as used for allcoation of
gigantic pages, a little more reliable to succeed.  However, if there is
demand for somewhat reliable allocation of gigantic pages, affected
setups should be using CMA or boottime allocations instead.

So let's make sure that pageblock_order < MAX_ORDER and simplify.

[1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com

Link: https://lkml.kernel.org/r/20220214174132.219303-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: John Garry via iommu <iommu@lists.linux-foundation.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:06 -07:00
Michael S. Tsirkin
e7c552ec89 virtio: drop default for virtio-mem
There's no special reason why virtio-mem needs a default that's
different from what kconfig provides, any more than e.g. virtio blk.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2022-03-06 06:06:50 -05:00
Si-Wei Liu
e0077cc13b vdpa: factor out vdpa_set_features_unlocked for vdpa internal use
No functional change introduced. vdpa bus driver such as virtio_vdpa
or vhost_vdpa is not supposed to take care of the locking for core
by its own. The locked API vdpa_set_features should suffice the
bus driver's need.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/1642206481-30721-2-git-send-email-si-wei.liu@oracle.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2022-03-04 11:56:33 -05:00
Michael S. Tsirkin
c46eccdaad virtio: document virtio_reset_device
Looks like most callers get driver/device removal wrong.
Document what's expected of callers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-04 08:33:22 -05:00
Michael S. Tsirkin
4fa59ede95 virtio: acknowledge all features before access
The feature negotiation was designed in a way that
makes it possible for devices to know which config
fields will be accessed by drivers.

This is broken since commit 404123c2db ("virtio: allow drivers to
validate features") with fallout in at least block and net.  We have a
partial work-around in commit 2f9a174f91 ("virtio: write back
F_VERSION_1 before validate") which at least lets devices find out which
format should config space have, but this is a partial fix: guests
should not access config space without acknowledging features since
otherwise we'll never be able to change the config space format.

To fix, split finalize_features from virtio_finalize_features and
call finalize_features with all feature bits before validation,
and then - if validation changed any bits - once again after.

Since virtio_finalize_features no longer writes out features
rename it to virtio_features_ok - since that is what it does:
checks that features are ok with the device.

As a side effect, this also reduces the amount of hypervisor accesses -
we now only acknowledge features once unless we are clearing any
features when validating (which is uncommon).

IRC I think that this was more or less always the intent in the spec but
unfortunately the way the spec is worded does not say this explicitly, I
plan to address this at the spec level, too.

Acked-by: Jason Wang <jasowang@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 404123c2db ("virtio: allow drivers to validate features")
Fixes: 2f9a174f91 ("virtio: write back F_VERSION_1 before validate")
Cc: "Halil Pasic" <pasic@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-04 08:33:21 -05:00
Michael S. Tsirkin
838d6d3461 virtio: unexport virtio_finalize_features
virtio_finalize_features is only used internally within virtio.
No reason to export it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2022-03-04 08:33:21 -05:00
Eli Cohen
aba21aff77 vdpa: Allow to configure max data virtqueues
Add netlink support to configure the max virtqueue pairs for a device.
At least one pair is required. The maximum is dictated by the device.

Example:
$ vdpa dev add name vdpa-a mgmtdev auxiliary/mlx5_core.sf.1 max_vqp 4

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-6-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
Eli Cohen
73bc0dbb59 vdpa: Sync calls set/get config/status with cf_mutex
Add wrappers to get/set status and protect these operations with
cf_mutex to serialize these operations with respect to get/set config
operations.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-4-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
Eli Cohen
a64917bc2e vdpa: Provide interface to read driver features
Provide an interface to read the negotiated features. This is needed
when building the netlink message in vdpa_dev_net_config_fill().

Also fix the implementation of vdpa_dev_net_config_fill() to use the
negotiated features instead of the device features.

To make APIs clearer, make the following name changes to struct
vdpa_config_ops so they better describe their operations:

get_features -> get_device_features
set_features -> set_driver_features

Finally, add get_driver_features to return the negotiated features and
add implementation to all the upstream drivers.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220105114646.577224-2-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
Michael S. Tsirkin
1861ba626a virtio_ring: mark ring unused on error
A recently added error path does not mark ring unused when exiting on
OOM, which will lead to BUG on the next entry in debug builds.

TODO: refactor code so we have START_USE and END_USE in the same function.

Fixes: fc6d70f40b ("virtio_ring: check desc == NULL when using indirect with packed")
Cc: "Xuan Zhuo" <xuanzhuo@linux.alibaba.com>
Cc: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
Peng Hao
49814ce9e2 virtio/virtio_pci_legacy_dev: ensure the correct return value
When pci_iomap return NULL, the return value is zero.

Signed-off-by: Peng Hao <flyingpeng@tencent.com>
Link: https://lore.kernel.org/r/20211222112014.87394-1-flyingpeng@tencent.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2022-01-14 18:50:53 -05:00
Peng Hao
cf4a4493ff virtio/virtio_mem: handle a possible NULL as a memcpy parameter
There is a check for vm->sbm.sb_states before, and it should check
it here as well.

Signed-off-by: Peng Hao <flyingpeng@tencent.com>
Link: https://lore.kernel.org/r/20211222011225.40573-1-flyingpeng@tencent.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Cc: stable@vger.kernel.org # v5.8+
2022-01-14 18:50:53 -05:00
Dapeng Mi
2b68224ec6 virtio: fix a typo in function "vp_modern_remove" comments.
Function name "vp_modern_remove" in comments is written to
"vp_modern_probe" incorrectly. Change it.

Signed-off-by: Dapeng Mi <dapeng1.mi@intel.com>
Link: https://lore.kernel.org/r/20211210073546.700783-1-dapeng1.mi@intel.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2022-01-14 18:50:53 -05:00
王贇
6017599bb2 virtio-pci: fix the confusing error message
The error message on the failure of pfn check should tell
virtio-pci rather than virtio-mmio, just fix it.

Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/ae5e154e-ac59-f0fa-a7c7-091a2201f581@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:53 -05:00
David Hildenbrand
57c5a5b304 virtio-mem: prepare fake page onlining code for granularity smaller than MAX_ORDER - 1
Let's prepare our fake page onlining code for subblock size smaller than
MAX_ORDER - 1: we might get called for ranges not covering properly
aligned MAX_ORDER - 1 pages. We have to detect the order to use
dynamically.

Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20211126134209.17332-3-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Eric Ren <renzhengeek@gmail.com>
2022-01-14 18:50:52 -05:00
David Hildenbrand
6639032acc virtio-mem: prepare page onlining code for granularity smaller than MAX_ORDER - 1
Let's prepare our page onlining code for subblock size smaller than
MAX_ORDER - 1: we'll get called for a MAX_ORDER - 1 page but might have
some subblocks in the range plugged and some unplugged. In that case,
fallback to subblock granularity to properly only expose the plugged
parts to the buddy.

Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20211126134209.17332-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Eric Ren <renzhengeek@gmail.com>
2022-01-14 18:50:52 -05:00
Michael S. Tsirkin
d9679d0013 virtio: wrap config->reset calls
This will enable cleanups down the road.
The idea is to disable cbs, then add "flush_queued_cbs" callback
as a parameter, this way drivers can flush any work
queued after callbacks have been disabled.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20211013105226.20225-1-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-14 18:50:52 -05:00
Will Deacon
817fc978b5 virtio_ring: Fix querying of maximum DMA mapping size for virtio device
virtio_max_dma_size() returns the maximum DMA mapping size of the virtio
device by querying dma_max_mapping_size() for the device when the DMA
API is in use for the vring. Unfortunately, the device passed is
initialised by register_virtio_device() and does not inherit the DMA
configuration from its parent, resulting in SWIOTLB errors when bouncing
is enabled and the default 256K mapping limit (IO_TLB_SEGSIZE) is not
respected:

  | virtio-pci 0000:00:01.0: swiotlb buffer is full (sz: 294912 bytes), total 1024 (slots), used 725 (slots)

Follow the pattern used elsewhere in the virtio_ring code when calling
into the DMA layer and pass the parent device to dma_max_mapping_size()
instead.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20211201112018.25276-1-will@kernel.org
Acked-by: Jason Wang <jasowang@redhat.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes: e6d6dd6c87 ("virtio: Introduce virtio_max_dma_size()")
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-12-08 15:04:06 -05:00
Michael S. Tsirkin
f124034faa Revert "virtio_ring: validate used buffer length"
This reverts commit 939779f515.

Attempts to validate length in the core did not work out: there turn out
to exist multiple broken devices, and in particular legacy devices are
known to be broken in this respect.

We have ideas for handling this better in the next version but for now
let's revert to a known good state to make sure drivers work for people.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-11-24 18:47:27 -05:00
David Hildenbrand
61082ad6a6 virtio-mem: support VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE
The initial virtio-mem spec states that while unplugged memory should not
be read, the device still has to allow for reading unplugged memory inside
the usable region. The primary motivation for this default handling was
to simplify bringup of virtio-mem, because there were corner cases where
Linux might have accidentially read unplugged memory inside added Linux
memory blocks.

In the meantime, we:
1. Removed /dev/kmem in commit bbcd53c960 ("drivers/char: remove
   /dev/kmem for good")
2. Disallowed access to virtio-mem device memory via /dev/mem in
   commit 2128f4e21a ("virtio-mem: disallow mapping virtio-mem memory via
   /dev/mem")
3. Sanitized access to virtio-mem device memory via /proc/kcore in
   commit 0daa322b8f ("fs/proc/kcore: don't read offline sections,
   logically offline pages and hwpoisoned pages")
4. Sanitized access to virtio-mem device memory via /proc/vmcore in
   commit ce2814622e ("virtio-mem: kdump mode to sanitize /proc/vmcore
   access")

"Accidential" access to unplugged memory is no longer possible; we can
support the new VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE feature that will be
required by some hypervisors implementing virtio-mem in the near future.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marek Kedzierski <mkedzier@redhat.com>
Cc: Hui Zhu <teawater@gmail.com>
Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
2021-11-10 15:32:38 +01:00
Linus Torvalds
59a2ceeef6 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...
2021-11-09 10:11:53 -08:00
David Hildenbrand
2128f4e21a virtio-mem: disallow mapping virtio-mem memory via /dev/mem
We don't want user space to be able to map virtio-mem device memory
directly (e.g., via /dev/mem) in order to have guarantees that in a sane
setup we'll never accidentially access unplugged memory within the
device-managed region of a virtio-mem device, just as required by the
virtio-spec.

As soon as the virtio-mem driver is loaded, the device region is visible
in /proc/iomem via the parent device region.  From that point on user
space is aware of the device region and we want to disallow mapping
anything inside that region (where we will dynamically (un)plug memory)
until the driver has been unloaded cleanly and e.g., another driver might
take over.

By creating our parent IORESOURCE_SYSTEM_RAM resource with
IORESOURCE_EXCLUSIVE, we will disallow any /dev/mem access to our device
region until the driver was unloaded cleanly and removed the parent
region.  This will work even though only some memory blocks are actually
currently added to Linux and appear as busy in the resource tree.

So access to the region from user space is only possible
a) if we don't load the virtio-mem driver.
b) after unloading the virtio-mem driver cleanly.

Don't build virtio-mem if access to /dev/mem cannot be restricticted -- if
we have CONFIG_DEVMEM=y but CONFIG_STRICT_DEVMEM is not set.

Link: https://lkml.kernel.org/r/20210920142856.17758-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09 10:02:52 -08:00
David Hildenbrand
ce2814622e virtio-mem: kdump mode to sanitize /proc/vmcore access
Although virtio-mem currently supports reading unplugged memory in the
hypervisor, this will change in the future, indicated to the device via
a new feature flag.

We similarly sanitized /proc/kcore access recently.  [1]

Let's register a vmcore callback, to allow vmcore code to check if a PFN
belonging to a virtio-mem device is either currently plugged and should
be dumped or is currently unplugged and should not be accessed, instead
mapping the shared zeropage or returning zeroes when reading.

This is important when not capturing /proc/vmcore via tools like
"makedumpfile" that can identify logically unplugged virtio-mem memory
via PG_offline in the memmap, but simply by e.g., copying the file.

Distributions that support virtio-mem+kdump have to make sure that the
virtio_mem module will be part of the kdump kernel or the kdump initrd;
dracut was recently [2] extended to include virtio-mem in the generated
initrd.  As long as no special kdump kernels are used, this will
automatically make sure that virtio-mem will be around in the kdump
initrd and sanitize /proc/vmcore access -- with dracut.

With this series, we'll send one virtio-mem state request for every ~2
MiB chunk of virtio-mem memory indicated in the vmcore that we intend to
read/map.

In the future, we might want to allow building virtio-mem for kdump mode
only, even without CONFIG_MEMORY_HOTPLUG and friends: this way, we could
support special stripped-down kdump kernels that have many other config
options disabled; we'll tackle that once required.  Further, we might
want to try sensing bigger blocks (e.g., memory sections) first before
falling back to device blocks on demand.

Tested with Fedora rawhide, which contains a recent kexec-tools version
(considering "System RAM (virtio_mem)" when creating the vmcore header)
and a recent dracut version (including the virtio_mem module in the
kdump initrd).

Link: https://lkml.kernel.org/r/20210526093041.8800-1-david@redhat.com [1]
Link: https://github.com/dracutdevs/dracut/pull/1157 [2]
Link: https://lkml.kernel.org/r/20211005121430.30136-10-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09 10:02:48 -08:00