linux-toradex.git/drivers/hv, branch v3.2.68

Drivers: hv: vmbus: incorrect device name is printed when child device is unregistered

2015-03-06T00:39:19+00:00

commit 84672369ffb98a51d4ddf74c20a23636da3ad615 upstream.

Whenever a device is unregistered in vmbus_device_unregister (drivers/hv/vmbus_drv.c), the device name in the log message may contain garbage as the memory has already been freed by the time pr_info is called. Log example:
 [ 3149.170475] hv_vmbus: child device àõsèè0_5 unregistered

By logging the message just before calling device_unregister, the correct device name is printed:
[ 3145.034652] hv_vmbus: child device vmbus_0_5 unregistered

Also changing register & unregister messages to debug to avoid unnecessarily cluttering the kernel log.

Signed-off-by: Fernando M Soto 
Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Cleanup hv_post_message()

2014-12-14T16:23:44+00:00

commit b29ef3546aecb253a5552b198cef23750d56e1e4 upstream.

Minimize failures in this function by pre-allocating the buffer
for posting messages. The hypercall for posting the message can fail
for a number of reasons:

        1. Transient resource related issues
        2. Buffer alignment
        3. Buffer cannot span a page boundry

We address issues 2 and 3 by preallocating a per-cpu page for the buffer.
Transient resource related failures are handled by retrying by the callers
of this function.

This patch is based on the investigation
done by Dexuan Cui .

I would like to thank Sitsofe Wheeler 
for reporting the issue and helping in debuggging.

Signed-off-by: K. Y. Srinivasan 
Reported-by: Sitsofe Wheeler 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.2:
 - s/NR_CPUS/MAX_NUM_CPUS/
 - Adjust context, indentation
 - Also free the page in hv_synic_init() error path]
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Cleanup vmbus_close_internal()

2014-12-14T16:23:44+00:00

commit 98d731bb064a9d1817a6ca9bf8b97051334a7cfe upstream.

Eliminate calls to BUG_ON() in vmbus_close_internal().
We have chosen to potentially leak memory, than crash the guest
in case of failures.

In this version of the patch I have addressed comments from
Dan Carpenter (dan.carpenter@oracle.com).

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.2: function is extern; don't change the return
 type to int as callers will ignore the value]
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Fix a bug in vmbus_open()

2014-12-14T16:23:43+00:00

commit 45d727cee9e200f5b351528b9fb063b69cf702c8 upstream.

Fix a bug in vmbus_open() and properly propagate the error. I would
like to thank Dexuan Cui  for identifying the
issue.

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Cleanup vmbus_establish_gpadl()

2014-12-14T16:23:43+00:00

commit 72c6b71c245dac8f371167d97ef471b367d0b66b upstream.

Eliminate the call to BUG_ON() by waiting for the host to respond. We are
trying to reclaim the ownership of memory that was given to the host and so
we will have to wait until the host responds.

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Cleanup vmbus_teardown_gpadl()

2014-12-14T16:23:43+00:00

commit 66be653083057358724d56d817e870e53fb81ca7 upstream.

Eliminate calls to BUG_ON() by properly handling errors. In cases where
rollback is possible, we will return the appropriate error to have the
calling code decide how to rollback state. In the case where we are
transferring ownership of the guest physical pages to the host,
we will wait for the host to respond.

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Cleanup vmbus_post_msg()

2014-12-14T16:23:43+00:00

commit fdeebcc62279119dbeafbc1a2e39e773839025fd upstream.

Posting messages to the host can fail because of transient resource
related failures. Correctly deal with these failures and increase the
number of attempts to post the message before giving up.

In this version of the patch, I have normalized the error code to
Linux error code.

Signed-off-by: K. Y. Srinivasan 
Tested-by: Sitsofe Wheeler 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

drivers: hv: additional switch to use mb() instead of smp_mb()

2014-04-30T15:23:27+00:00

commit e4af376d04b0(drivers: hv: switch to use mb() instead of smp_mb()),
the adjustment mistakenly dropped the change in hv_ringbuffer_read,
so add it.

Signed-off-by: Qiang Huang 
Signed-off-by: Ben Hutchings

Drivers: hv: vmbus: Don't timeout during the initial connection with host

2014-04-01T23:58:49+00:00

commit 269f979467cf49f2ea8132316c1f00f8c9678f7c upstream.

When the guest attempts to connect with the host when there may already be a
connection with the host (as would be the case during the kdump/kexec path),
it is difficult to guarantee timely response from the host. Starting with
WS2012 R2, the host supports this ability to re-connect with the host
(explicitly to support kexec). Prior to responding to the guest, the host
needs to ensure that device states based on the previous connection to
the host have been properly torn down. This may introduce unbounded delays.
To deal with this issue, don't do a timed wait during the initial connect
with the host.

Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

drivers: hv: switch to use mb() instead of smp_mb()

2013-07-27T04:34:12+00:00

commit 35848f68b07df3f917cb13fc3c134718669f569b upstream.

Even if guest were compiled without SMP support, it could not assume that host
wasn't. So switch to use mb() instead of smp_mb() to force memory barriers for
UP guest.

Signed-off-by: Jason Wang 
Cc: Haiyang Zhang 
Signed-off-by: K. Y. Srinivasan 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.2:
 - Drop changes to functions that don't exist here
 - hv_ringbuffer_write() has only a write memory barrier]
Signed-off-by: Ben Hutchings