There's no difference in supporting S3 and S4 for virtio devices: the
vqs have to be re-created as the device has to be assumed to be reset at
restore-time. Since S4 already handles this situation, we can directly
use the same code and callbacks for S3 support.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
restore_common() was shared between restore and thaw callbacks. With
thaw gone, we don't need restore_common() anymore.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
The thaw operation was used by the balloon driver, but after the last
commit there's no reason to have separate thaw and restore callbacks.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Handle thaw, restore and freeze notifications from the PM core. Expose
these to individual virtio drivers that can quiesce and resume vq
operations. For drivers not implementing the thaw() method, use the
restore method instead.
These functions also save device-specific data so that the device can be
put in pre-suspend state after resume, and disable and enable the PCI
device in the freeze and resume functions, respectively.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The older PM API doesn't have a way to get notifications on hibernate
events. Switch to the newer one that gives us those notifications.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We were cheating with our barriers; using the smp ones rather than the
real device ones. That was fine, until rpmsg came along, which is
used to talk to a real device (a non-SMP CPU).
Unfortunately, just putting back the real barriers (reverting
d57ed95d) causes a performance regression on virtio-pci. In
particular, Amos reports netbench's TCP_RR over virtio_net CPU
utilization increased up to 35% while throughput went down by up to
14%.
By comparison, this branch is in the noise.
Reference: https://lkml.org/lkml/2011/12/11/22
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio pci device reset actually just does an I/O
write, which in PCI is really posted, that is it
can complete on CPU before the device has received it.
Further, interrupts might have been pending on
another CPU, so device callback might get invoked after reset.
This conflicts with how drivers use reset, which is typically:
reset
unregister
a callback running after reset completed can race with
unregister, potentially leading to use after free bugs.
Fix by flushing out the write, and flushing pending interrupts.
This assumes that device is never reset from
its vq/config callbacks, or in parallel with being
added/removed, document this assumption.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The forcedeth changes had a conflict with the conversion over
to atomic u64 statistics in net-next.
The libertas cfg.c code had a conflict with the bss reference
counting fix by John Linville in net-next.
Conflicts:
drivers/net/ethernet/nvidia/forcedeth.c
drivers/net/wireless/libertas/cfg.c
Add a new .bus_name to virtio_config_ops then modify virtio_net to
call through to it in an ethtool .get_drvinfo routine to report
bus_info in ethtool -i output which is consistent with other
emulated NICs and the output of lspci.
Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 31a3ddda16 introduced
a use after free in virtio-pci. The main issue is
that the release method signals removal of the virtio device,
while remove signals removal of the pci device.
For example, on driver removal or hot-unplug,
virtio_pci_release_dev is called before virtio_pci_remove.
We then might get a crash as virtio_pci_remove tries to use the
device freed by virtio_pci_release_dev.
We allocate/free all resources together with the
pci device, so we can leave the release method empty.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
For the MSI but non-per_vq_vector case, the config/change vq
also gets added to the list of vqs that need to process the
MSI interrupt. This is not needed as config has it's own
handler (vp_config_changed). In any case, vring_interrupt()
finds nothing needs to be done on this vq.
I tested this patch by testing the "Fallback:" and "Finally
fall back" cases in vp_find_vqs(). Please review.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In the case where a virtio-console port is in use (opened by a program)
and a virtio-console device is removed, the port is kept around but all
the virtio-related state is assumed to be gone.
When the port is finally released (close() called), we call
device_destroy() on the port's device. This results in the parent
device's structures to be freed as well. This includes the PCI regions
for the virtio-console PCI device.
Once this is done, however, virtio_pci_release_dev() kicks in, as the
last ref to the virtio device is now gone, and attempts to do
pci_iounmap(pci_dev, vp_dev->ioaddr);
pci_release_regions(pci_dev);
pci_disable_device(pci_dev);
which results in a double-free warning.
Move the code that releases regions, etc., to the virtio_pci_remove()
function, and all that's now left in release_dev is the final freeing of
the vp_dev.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We sometimes need to map between the virtio device and
the given pci device. One such use is OS installer that
gets the boot pci device from BIOS and needs to
find the relevant block device. Since it can't,
installation fails.
Instead of creating a top-level devices/virtio-pci
directory, create each device under the corresponding
pci device node. Symlinks to all virtio-pci
devices can be found under the pci driver link in
bus/pci/drivers/virtio-pci/devices, and all virtio
devices under drivers/bus/virtio/devices.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Gleb Natapov <gleb@redhat.com>
Tested-by: "Daniel P. Berrange" <berrange@redhat.com>
Cc: stable@kernel.org
virtio-pci resets the device at startup by writing to the status
register, but this does not clear the pci config space,
specifically msi enable status which affects register
layout.
This breaks things like kdump when they try to use e.g. virtio-blk.
Fix by forcing msi off at startup. Since pci.c already has
a routine to do this, we export and use it instead of duplicating code.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
As all virtio devices perform DMA, we
must enable bus mastering for them to be
spec compliant.
This patch fixes hotplug of virtio devices
with Linux guests and qemu 0.11-0.12.
Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
I have observed the following error on virtio-net module unload:
------------[ cut here ]------------
WARNING: at kernel/irq/manage.c:858 __free_irq+0xa0/0x14c()
Hardware name: Bochs
Trying to free already-free IRQ 0
Modules linked in: virtio_net(-) virtio_blk virtio_pci virtio_ring
virtio af_packet e1000 shpchp aacraid uhci_hcd ohci_hcd ehci_hcd [last
unloaded: scsi_wait_scan]
Pid: 1957, comm: rmmod Not tainted 2.6.33-rc8-vhost #24
Call Trace:
[<ffffffff8103e195>] warn_slowpath_common+0x7c/0x94
[<ffffffff8103e204>] warn_slowpath_fmt+0x41/0x43
[<ffffffff810a7a36>] ? __free_pages+0x5a/0x70
[<ffffffff8107cc00>] __free_irq+0xa0/0x14c
[<ffffffff8107cceb>] free_irq+0x3f/0x65
[<ffffffffa0081424>] vp_del_vqs+0x81/0xb1 [virtio_pci]
[<ffffffffa0091d29>] virtnet_remove+0xda/0x10b [virtio_net]
[<ffffffffa0075200>] virtio_dev_remove+0x22/0x4a [virtio]
[<ffffffff812709ee>] __device_release_driver+0x66/0xac
[<ffffffff81270ab7>] driver_detach+0x83/0xa9
[<ffffffff8126fc66>] bus_remove_driver+0x91/0xb4
[<ffffffff81270fcf>] driver_unregister+0x6c/0x74
[<ffffffffa0075418>] unregister_virtio_driver+0xe/0x10 [virtio]
[<ffffffffa0091c4d>] fini+0x15/0x17 [virtio_net]
[<ffffffff8106997b>] sys_delete_module+0x1c3/0x230
[<ffffffff81007465>] ? old_ich_force_enable_hpet+0x117/0x164
[<ffffffff813bb720>] ? do_page_fault+0x29c/0x2cc
[<ffffffff81028e58>] sysenter_dispatch+0x7/0x27
---[ end trace 15e88e4c576cc62b ]---
The bug is in virtio-pci: we use msix_vector as array index to get irq
entry, but some vqs do not have a dedicated vector so this causes an out
of bounds access. By chance, we seem to often get 0 value, which
results in this error.
Fix by verifying that vector is legal before using it as index.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Acked-by: Shirley Ma <xma@us.ibm.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
This is needed to compile with CONFIG_VIRTIO_PCI=y,
because virtio_pci_remove is marked __devexit.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit f68d24082e
in 2.6.32-rc1 broke requesting IRQs for per-VQ MSI-X vectors:
- vector number was used instead of the vector itself
- we try to request an IRQ for VQ which does not
have a callback handler
This is a regression that causes warnings in kernel log,
potentially lower performance as we need to scan vq list,
and might cause system failure if the interrupt
requested is in fact needed by another system.
This was not noticed earlier because in most cases
we were falling back on shared interrupt for all vqs.
The warnings often look like this:
virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 28 for MSI/MSI-X
IRQ handler type mismatch for IRQ 1
current handler: i8042
Pid: 2400, comm: modprobe Tainted: G W
2.6.32-rc3-11952-gf3ed8d8-dirty #1
Call Trace:
[<ffffffff81072aed>] ? __setup_irq+0x299/0x304
[<ffffffff81072ff3>] ? request_threaded_irq+0x144/0x1c1
[<ffffffff813455af>] ? vring_interrupt+0x0/0x30
[<ffffffff81346598>] ? vp_try_to_find_vqs+0x583/0x5c7
[<ffffffffa0015188>] ? skb_recv_done+0x0/0x34 [virtio_net]
[<ffffffff81346609>] ? vp_find_vqs+0x2d/0x83
[<ffffffff81345d00>] ? vp_get+0x3c/0x4e
[<ffffffffa0016373>] ? virtnet_probe+0x2f1/0x428 [virtio_net]
[<ffffffffa0015188>] ? skb_recv_done+0x0/0x34 [virtio_net]
[<ffffffffa00150d8>] ? skb_xmit_done+0x0/0x39 [virtio_net]
[<ffffffff8110ab92>] ? sysfs_do_create_link+0xcb/0x116
[<ffffffff81345cc2>] ? vp_get_status+0x14/0x16
[<ffffffff81345464>] ? virtio_dev_probe+0xa9/0xc8
[<ffffffff8122b11c>] ? driver_probe_device+0x8d/0x128
[<ffffffff8122b206>] ? __driver_attach+0x4f/0x6f
[<ffffffff8122b1b7>] ? __driver_attach+0x0/0x6f
[<ffffffff8122a9f9>] ? bus_for_each_dev+0x43/0x74
[<ffffffff8122a374>] ? bus_add_driver+0xea/0x22d
[<ffffffff8122b4a3>] ? driver_register+0xa7/0x111
[<ffffffffa001a000>] ? init+0x0/0xc [virtio_net]
[<ffffffff81009051>] ? do_one_initcall+0x50/0x148
[<ffffffff8106e117>] ? sys_init_module+0xc5/0x21a
[<ffffffff8100af02>] ? system_call_fastpath+0x16/0x1b
virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X
virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Reported-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
1) Rename vp_request_vectors to vp_request_msix_vectors, and take
non-MSI-X case out to caller.
2) Comment weird pci_enable_msix API
3) Rename vp_find_vq to setup_vq.
4) Fix spaces to tabs
5) Make nvectors calc internal to vp_try_to_find_vqs()
6) Rename vector to msix_vector for more clarity.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
This refactors find_vqs, making it more readable and robust, and fixing
two regressions from 2.6.30:
- double free_irq causing BUG_ON on device removal
- probe failure when vq can't be assigned to msi-x vector
(reported on old host kernels)
Tested-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Amit Shah
Rusty Russell
David S. Miller
Michael S. Tsirkin
Rick Jones
Krishna Kumar
Milton Miller
Jiri Kosina
Tejun Heo
Thomas Weber
Jamie Lokier