search for: unplugged

virtio-scsi currently has limit of 8 outstanding notifications so when more that 8 LUNs are unplugged, some are missed. Commit 5ff843721467 ("scsi: virtio_scsi: unplug LUNs when events missed") Fixed this by checking the 'event overflow' bit and manually scanned the bus to see which LUNs are still there. However there is a corner case when all LUNs are unplugged. In this case (w...

On 07/19/2013 04:16 AM, Amit Shah wrote: > If a port gets unplugged while a user is blocked on read(), -ENODEV is > returned. However, subsequent read()s returned 0, indicating there's no > host-side connection (but not indicating the device went away). > > This also happened when a port was unplugged and the user didn't have > any blocking...

On 07/19/2013 04:16 AM, Amit Shah wrote: > If a port gets unplugged while a user is blocked on read(), -ENODEV is > returned. However, subsequent read()s returned 0, indicating there's no > host-side connection (but not indicating the device went away). > > This also happened when a port was unplugged and the user didn't have > any blocking...

...mmand line because it is in effect set by the user''s image. Therefore what I need to do is prevent Xen4 offering the facility to unplug the devices in the first place. Setting "(unpluggable 0)" in the config for the emulated NICs and disks does not appear to prevent them getting unplugged; what may be happening is that domU tries to unplug them (but fails) but still doesn''t use them. Is there a way to signal from dom0 that the kernel really shouldn''t unplug this stuff. -- Alex Bligh _______________________________________________ Xen-devel mailing list Xen-devel...

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches

...nts memory hot(un)plug > under Linux - like s390x, powerpc64, and arm64. On x86-64, it is currently > possible to add/remove memory to the system in >= 4MB granularity. > Memory hotplug works very reliably. For memory unplug, there are no > guarantees how much memory can actually get unplugged, it depends on the > setup (especially: fragmentation of physical memory). > > I am currently getting the QEMU side into shape (which will be posted as > RFC soon, see below for a link to the current state). Experimental Kata > support is in the works [4]. Also, a cloud-hypervisor i...

Hello, This series fixes a few races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches for

Hello, This series fixes a few races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches for

I just had a DomU start up where for some reason the qemu devices failed to be unplugged. Fortunately Windows saw this as two paths to the same disk instead of two separate disks so nothing got scrambled, but the network was dropping out all the time etc. Are there any circumstances under which the qemu unplug could fail to work? And if so, how could I tell? More likely some race con...

...oretically work on any Linux architecture that implements memory hot(un)plug - like s390x. On x86-64, it is currently possible to add/remove memory to the system in >= 4MB granularity. Memory hotplug works very reliable. For memory unplug, there are no guarantees how much memory can actually get unplugged, it depends on the setup. I have plans to improve that in the future. -------------------------------------------------------------------------- 1. virtio-mem -------------------------------------------------------------------------- The basic idea behind virtio-mem was presented at KVM Forum 201...

...s well. Hopefully this will be in time for the next merge window. There's one use-after-free I spotted after sending the first two versions: port_fops_release() calls send_control_msg(), which spins till the host acknowledges receipt of the buffer. While it's spinning, if the device gets unplugged, the vqs go away, and the spinning function never progresses, causing a softlockup. This is difficult to reproduce -- the host usually acknowledges the buffers fast enough. A couple of solutions for this case are possible: 1. Mark the control vq in use, and don't proceed with unplug till it&...

...s well. Hopefully this will be in time for the next merge window. There's one use-after-free I spotted after sending the first two versions: port_fops_release() calls send_control_msg(), which spins till the host acknowledges receipt of the buffer. While it's spinning, if the device gets unplugged, the vqs go away, and the spinning function never progresses, causing a softlockup. This is difficult to reproduce -- the host usually acknowledges the buffers fast enough. A couple of solutions for this case are possible: 1. Mark the control vq in use, and don't proceed with unplug till it&...

On 07/19/2013 04:16 AM, Amit Shah wrote: > Between poll() being called and processed, the port can be unplugged. > Check if this happened, and bail out. > > Signed-off-by: Amit Shah <amit.shah at redhat.com> > --- > drivers/char/virtio_console.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c > index...

On 07/19/2013 04:16 AM, Amit Shah wrote: > Between poll() being called and processed, the port can be unplugged. > Check if this happened, and bail out. > > Signed-off-by: Amit Shah <amit.shah at redhat.com> > --- > drivers/char/virtio_console.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c > index...

...ked. >> > >> > Signed-off-by: Amit Shah <amit.shah at redhat.com> >> >> How can userspace access the port now? By the time we are cleaning up >> buffers, there should be no possibility of such accesses. > > close(), can happen when the port is being unplugged. We're just > making sure here that port_fops_release() and unplug_port() don't try > to free up the same data at the same time. Why doesn't reference counting help us here? Surely the last one should clean up? >> The number of bugfixes here is deeply disturbing. > &g...

...ked. >> > >> > Signed-off-by: Amit Shah <amit.shah at redhat.com> >> >> How can userspace access the port now? By the time we are cleaning up >> buffers, there should be no possibility of such accesses. > > close(), can happen when the port is being unplugged. We're just > making sure here that port_fops_release() and unplug_port() don't try > to free up the same data at the same time. Why doesn't reference counting help us here? Surely the last one should clean up? >> The number of bugfixes here is deeply disturbing. > &g...

...wing: virsh # setvcpus pathway 3 --live virsh # setvcpus pathway 4 --live virsh # setvcpus pathway 2 --live error: internal error: unable to execute QEMU command 'device_del': acpi: device unplug request for not supported device type: qemu64-x86_64-cpu Does anyone know why it can't be unplugged ? Thanks. Brtnf -- Bernd Lentes Systemadministration Institute for Metabolism and Cell Death (MCD) Building 35.34 - Raum 208 HelmholtzZentrum münchen bernd.lentes@helmholtz-muenchen.de phone: +49 89 3187 1241 phone: +49 89 3187 3827 fax: +49 89 3187 2294 http://www.helmholtz-muenchen...

...ts virtio and implements memory hot(un)plug under Linux - like s390x, powerpc64 and arm64. On x86-64, it is currently possible to add/remove memory to the system in >= 4MB granularity. Memory hotplug works very reliably. For memory unplug, there are no guarantees how much memory can actually get unplugged, it depends on the setup (especially: fragmentation of (unmovable) memory). I have plans to improve that in the future. -------------------------------------------------------------------------- 1. virtio-mem -------------------------------------------------------------------------- The basic ide...

...ts virtio and implements memory hot(un)plug under Linux - like s390x, powerpc64 and arm64. On x86-64, it is currently possible to add/remove memory to the system in >= 4MB granularity. Memory hotplug works very reliably. For memory unplug, there are no guarantees how much memory can actually get unplugged, it depends on the setup (especially: fragmentation of (unmovable) memory). I have plans to improve that in the future. -------------------------------------------------------------------------- 1. virtio-mem -------------------------------------------------------------------------- The basic ide...