similar to: [PATCH 00/10] virtio: console: fixes for races with port unplug

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write() and close(). I started coding up an alternative locking mechanism based on the discussion earlier in this series, but some of what we already have has to remain, and the new code is sufficiently different, so I'd rather it bakes for a while, and I ensure there are no regressions

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write() and close(). I started coding up an alternative locking mechanism based on the discussion earlier in this series, but some of what we already have has to remain, and the new code is sufficiently different, so I'd rather it bakes for a while, and I ensure there are no regressions

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

Hey Rusty, This patchset is on top of the previous one. It sends a SIGIO signal to apps that request signals for host activity. SIGIO is sent on host connect, disconnect as well as hot-unplug (which can be seen as a special case of host disconnect). Tested using several testcases in the test-virtserial repo: http://fedorapeople.org/gitweb?p=amitshah/public_git/test-virtserial.git Please apply.

Hey Rusty, This patchset is on top of the previous one. It sends a SIGIO signal to apps that request signals for host activity. SIGIO is sent on host connect, disconnect as well as hot-unplug (which can be seen as a special case of host disconnect). Tested using several testcases in the test-virtserial repo: http://fedorapeople.org/gitweb?p=amitshah/public_git/test-virtserial.git Please apply.

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 operation pending. If the

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 operation pending. If the

Hi Rusty, The main thing in these patches is the introduction of injecting SIGIO on host-side connect/disconnect events and when new data is available for ports. The first two patches fix bugs that I haven't seen, but look like the right thing to do. These have been tested extensively using the test-virtserial test suite. Please apply, Amit. Amit Shah (4): virtio: console: Un-block

Hi Rusty, The main thing in these patches is the introduction of injecting SIGIO on host-side connect/disconnect events and when new data is available for ports. The first two patches fix bugs that I haven't seen, but look like the right thing to do. These have been tested extensively using the test-virtserial test suite. Please apply, Amit. Amit Shah (4): virtio: console: Un-block

Hey Rusty, These are the patches that rework a few bits to make hot-unplug while ports are open not crash apps (or kernels). The problem is when hot-unplug is performed when a port is open, the cdev struct is kept around by the file pointers and when the app later does a 'close', things go boom-boom. This patch series makes sure port as well as device hot-unplug is now safe to perform

Hey Rusty, These are the patches that rework a few bits to make hot-unplug while ports are open not crash apps (or kernels). The problem is when hot-unplug is performed when a port is open, the cdev struct is kept around by the file pointers and when the app later does a 'close', things go boom-boom. This patch series makes sure port as well as device hot-unplug is now safe to perform

Returning EMFILE (process has too many open files) is incorrect to indicate a port is already open by another process. Use EBUSY for that. This does change what we report to userspace, but I believe userspace can look at it this way: it gets EBUSY, a new error code, instead of EMFILE. It's still an error, and that's not changing. Reported-by: Mateusz Guzik <mguzik at redhat.com>

Returning EMFILE (process has too many open files) is incorrect to indicate a port is already open by another process. Use EBUSY for that. This does change what we report to userspace, but I believe userspace can look at it this way: it gets EBUSY, a new error code, instead of EMFILE. It's still an error, and that's not changing. Reported-by: Mateusz Guzik <mguzik at redhat.com>

Amit Shah <amit.shah at redhat.com> writes: > On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >> On 07/19/2013 03:48 PM, Amit Shah wrote: >> > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> >> On 07/19/2013 04:16 AM, Amit Shah wrote: >> >>> Between poll() being called and processed, the port can be unplugged. >> >>> Check

Amit Shah <amit.shah at redhat.com> writes: > On (Fri) 19 Jul 2013 [18:17:32], Jason Wang wrote: >> On 07/19/2013 03:48 PM, Amit Shah wrote: >> > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> >> On 07/19/2013 04:16 AM, Amit Shah wrote: >> >>> Between poll() being called and processed, the port can be unplugged. >> >>> Check

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

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

On 07/19/2013 03:48 PM, Amit Shah wrote: > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> 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> >>> --- >>>

On 07/19/2013 03:48 PM, Amit Shah wrote: > On (Fri) 19 Jul 2013 [15:03:50], Jason Wang wrote: >> 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> >>> --- >>>