<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/usb/usbip, branch linux-5.6.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>usbip: Fix error path of vhci_recv_ret_submit()</title>
<updated>2019-12-17T15:36:33+00:00</updated>
<author>
<name>Suwan Kim</name>
<email>suwan.kim027@gmail.com</email>
</author>
<published>2019-12-13T02:30:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=aabb5b833872524eaf28f52187e5987984982264'/>
<id>aabb5b833872524eaf28f52187e5987984982264</id>
<content type='text'>
If a transaction error happens in vhci_recv_ret_submit(), event
handler closes connection and changes port status to kick hub_event.
Then hub tries to flush the endpoint URBs, but that causes infinite
loop between usb_hub_flush_endpoint() and vhci_urb_dequeue() because
"vhci_priv" in vhci_urb_dequeue() was already released by
vhci_recv_ret_submit() before a transmission error occurred. Thus,
vhci_urb_dequeue() terminates early and usb_hub_flush_endpoint()
continuously calls vhci_urb_dequeue().

The root cause of this issue is that vhci_recv_ret_submit()
terminates early without giving back URB when transaction error
occurs in vhci_recv_ret_submit(). That causes the error URB to still
be linked at endpoint list without “vhci_priv".

So, in the case of transaction error in vhci_recv_ret_submit(),
unlink URB from the endpoint, insert proper error code in
urb-&gt;status and give back URB.

Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191213023055.19933-3-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If a transaction error happens in vhci_recv_ret_submit(), event
handler closes connection and changes port status to kick hub_event.
Then hub tries to flush the endpoint URBs, but that causes infinite
loop between usb_hub_flush_endpoint() and vhci_urb_dequeue() because
"vhci_priv" in vhci_urb_dequeue() was already released by
vhci_recv_ret_submit() before a transmission error occurred. Thus,
vhci_urb_dequeue() terminates early and usb_hub_flush_endpoint()
continuously calls vhci_urb_dequeue().

The root cause of this issue is that vhci_recv_ret_submit()
terminates early without giving back URB when transaction error
occurs in vhci_recv_ret_submit(). That causes the error URB to still
be linked at endpoint list without “vhci_priv".

So, in the case of transaction error in vhci_recv_ret_submit(),
unlink URB from the endpoint, insert proper error code in
urb-&gt;status and give back URB.

Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191213023055.19933-3-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: Fix receive error in vhci-hcd when using scatter-gather</title>
<updated>2019-12-17T15:36:32+00:00</updated>
<author>
<name>Suwan Kim</name>
<email>suwan.kim027@gmail.com</email>
</author>
<published>2019-12-13T02:30:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d986294ee55d719562b20aabe15a39bf8f863415'/>
<id>d986294ee55d719562b20aabe15a39bf8f863415</id>
<content type='text'>
When vhci uses SG and receives data whose size is smaller than SG
buffer size, it tries to receive more data even if it acutally
receives all the data from the server. If then, it erroneously adds
error event and triggers connection shutdown.

vhci-hcd should check if it received all the data even if there are
more SG entries left. So, check if it receivces all the data from
the server in for_each_sg() loop.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20191213023055.19933-2-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When vhci uses SG and receives data whose size is smaller than SG
buffer size, it tries to receive more data even if it acutally
receives all the data from the server. If then, it erroneously adds
error event and triggers connection shutdown.

vhci-hcd should check if it received all the data even if there are
more SG entries left. So, check if it receivces all the data from
the server in for_each_sg() loop.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Tested-by: Marek Marczykowski-Górecki &lt;marmarek@invisiblethingslab.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20191213023055.19933-2-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: Fix uninitialized symbol 'nents' in stub_recv_cmd_submit()</title>
<updated>2019-11-13T10:53:11+00:00</updated>
<author>
<name>Suwan Kim</name>
<email>suwan.kim027@gmail.com</email>
</author>
<published>2019-11-11T14:10:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2a9125317b247f2cf35c196f968906dcf062ae2d'/>
<id>2a9125317b247f2cf35c196f968906dcf062ae2d</id>
<content type='text'>
Smatch reported that nents is not initialized and used in
stub_recv_cmd_submit(). nents is currently initialized by sgl_alloc()
and used to allocate multiple URBs when host controller doesn't
support scatter-gather DMA. The use of uninitialized nents means that
buf_len is zero and use_sg is true. But buffer length should not be
zero when an URB uses scatter-gather DMA.

To prevent this situation, add the conditional that checks buf_len
and use_sg. And move the use of nents right after the sgl_alloc() to
avoid the use of uninitialized nents.

If the error occurs, it adds SDEV_EVENT_ERROR_MALLOC and stub_priv
will be released by stub event handler and connection will be shut
down.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Reported-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20191111141035.27788-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Smatch reported that nents is not initialized and used in
stub_recv_cmd_submit(). nents is currently initialized by sgl_alloc()
and used to allocate multiple URBs when host controller doesn't
support scatter-gather DMA. The use of uninitialized nents means that
buf_len is zero and use_sg is true. But buffer length should not be
zero when an URB uses scatter-gather DMA.

To prevent this situation, add the conditional that checks buf_len
and use_sg. And move the use of nents right after the sgl_alloc() to
avoid the use of uninitialized nents.

If the error occurs, it adds SDEV_EVENT_ERROR_MALLOC and stub_priv
will be released by stub event handler and connection will be shut
down.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Reported-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/20191111141035.27788-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USBIP: add config dependency for SGL_ALLOC</title>
<updated>2019-11-12T17:19:22+00:00</updated>
<author>
<name>Oliver Neukum</name>
<email>oneukum@suse.com</email>
</author>
<published>2019-11-12T15:49:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1ec13abac58b6f24e32f0d3081ef4e7456e62ed8'/>
<id>1ec13abac58b6f24e32f0d3081ef4e7456e62ed8</id>
<content type='text'>
USBIP uses lib/scatterlist.h
Hence it needs to set CONFIG_SGL_ALLOC

Signed-off-by: Oliver Neukum &lt;oneukum@suse.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191112154939.21217-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
USBIP uses lib/scatterlist.h
Hence it needs to set CONFIG_SGL_ALLOC

Signed-off-by: Oliver Neukum &lt;oneukum@suse.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191112154939.21217-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge 5.4-rc6 into usb-next</title>
<updated>2019-11-04T05:41:09+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2019-11-04T05:41:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=16c8373ecf7b3c723a8e765d798ea413bc8345a6'/>
<id>16c8373ecf7b3c723a8e765d798ea413bc8345a6</id>
<content type='text'>
We need the USB fixes in here to build on top of.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We need the USB fixes in here to build on top of.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: Fix free of unallocated memory in vhci tx</title>
<updated>2019-10-28T16:51:06+00:00</updated>
<author>
<name>Suwan Kim</name>
<email>suwan.kim027@gmail.com</email>
</author>
<published>2019-10-22T09:30:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d4d8257754c3300ea2a465dadf8d2b02c713c920'/>
<id>d4d8257754c3300ea2a465dadf8d2b02c713c920</id>
<content type='text'>
iso_buffer should be set to NULL after use and free in the while loop.
In the case of isochronous URB in the while loop, iso_buffer is
allocated and after sending it to server, buffer is deallocated. And
then, if the next URB in the while loop is not a isochronous pipe,
iso_buffer still holds the previously deallocated buffer address and
kfree tries to free wrong buffer address.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Reported-by: Julia Lawall &lt;julia.lawall@lip6.fr&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Reviewed-by: Julia Lawall &lt;julia.lawall@lip6.fr&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191022093017.8027-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
iso_buffer should be set to NULL after use and free in the while loop.
In the case of isochronous URB in the while loop, iso_buffer is
allocated and after sending it to server, buffer is deallocated. And
then, if the next URB in the while loop is not a isochronous pipe,
iso_buffer still holds the previously deallocated buffer address and
kfree tries to free wrong buffer address.

Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver")
Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Reported-by: Julia Lawall &lt;julia.lawall@lip6.fr&gt;
Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Reviewed-by: Julia Lawall &lt;julia.lawall@lip6.fr&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20191022093017.8027-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge 5.4-rc3 into usb-next</title>
<updated>2019-10-14T05:09:59+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2019-10-14T05:09:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf7c1d95af67254957d1820ac112397001e1a9a9'/>
<id>bf7c1d95af67254957d1820ac112397001e1a9a9</id>
<content type='text'>
we want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
we want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: clean up an indentation issue</title>
<updated>2019-10-04T12:09:42+00:00</updated>
<author>
<name>Colin Ian King</name>
<email>colin.king@canonical.com</email>
</author>
<published>2019-09-27T09:20:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=faf4b0dcea31f28979b5cde706d3e5d7b4ad840d'/>
<id>faf4b0dcea31f28979b5cde706d3e5d7b4ad840d</id>
<content type='text'>
There is a return statement that is indented incorrectly, fix this.

Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Link: https://lore.kernel.org/r/20190927092000.19373-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is a return statement that is indented incorrectly, fix this.

Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Link: https://lore.kernel.org/r/20190927092000.19373-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: vhci_hcd indicate failed message</title>
<updated>2019-10-04T09:02:59+00:00</updated>
<author>
<name>Mao Wenan</name>
<email>maowenan@huawei.com</email>
</author>
<published>2019-09-16T15:09:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3f384d7c490374b2ae8f61a6c67f14deab77bab2'/>
<id>3f384d7c490374b2ae8f61a6c67f14deab77bab2</id>
<content type='text'>
If the return value of vhci_init_attr_group and
sysfs_create_group is non-zero, which mean they failed
to init attr_group and create sysfs group, so it would
better add 'failed' message to indicate that.
This patch also change pr_err to dev_err to trace which
device is failed.

Fixes: 0775a9cbc694 ("usbip: vhci extension: modifications to vhci driver")
Signed-off-by: Mao Wenan &lt;maowenan@huawei.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20190916150921.152977-1-maowenan@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If the return value of vhci_init_attr_group and
sysfs_create_group is non-zero, which mean they failed
to init attr_group and create sysfs group, so it would
better add 'failed' message to indicate that.
This patch also change pr_err to dev_err to trace which
device is failed.

Fixes: 0775a9cbc694 ("usbip: vhci extension: modifications to vhci driver")
Signed-off-by: Mao Wenan &lt;maowenan@huawei.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20190916150921.152977-1-maowenan@huawei.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usbip: Implement SG support to vhci-hcd and stub driver</title>
<updated>2019-09-03T14:00:38+00:00</updated>
<author>
<name>Suwan Kim</name>
<email>suwan.kim027@gmail.com</email>
</author>
<published>2019-08-28T03:27:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ea44d190764b4422af4d1c29eaeb9e69e353b406'/>
<id>ea44d190764b4422af4d1c29eaeb9e69e353b406</id>
<content type='text'>
There are bugs on vhci with usb 3.0 storage device. In USB, each SG
list entry buffer should be divisible by the bulk max packet size.
But with native SG support, this problem doesn't matter because the
SG buffer is treated as contiguous buffer. But without native SG
support, USB storage driver breaks SG list into several URBs and the
error occurs because of a buffer size of URB that cannot be divided
by the bulk max packet size. The error situation is as follows.

When USB Storage driver requests 31.5 KB data and has SG list which
has 3584 bytes buffer followed by 7 4096 bytes buffer for some
reason. USB Storage driver splits this SG list into several URBs
because VHCI doesn't support SG and sends them separately. So the
first URB buffer size is 3584 bytes. When receiving data from device,
USB 3.0 device sends data packet of 1024 bytes size because the max
packet size of BULK pipe is 1024 bytes. So device sends 4096 bytes.
But the first URB buffer has only 3584 bytes buffer size. So host
controller terminates the transfer even though there is more data to
receive. So, vhci needs to support SG transfer to prevent this error.

In this patch, vhci supports SG regardless of whether the server's
host controller supports SG or not, because stub driver splits SG
list into several URBs if the server's host controller doesn't
support SG.

To support SG, vhci sets URB_DMA_MAP_SG flag in urb-&gt;transfer_flags
if URB has SG list and this flag will tell stub driver to use SG
list. After receiving urb from stub driver, vhci clear URB_DMA_MAP_SG
flag to avoid unnecessary DMA unmapping in HCD.

vhci sends each SG list entry to stub driver. Then, stub driver sees
the total length of the buffer and allocates SG table and pages
according to the total buffer length calling sgl_alloc(). After stub
driver receives completed URB, it again sends each SG list entry to
vhci.

If the server's host controller doesn't support SG, stub driver
breaks a single SG request into several URBs and submits them to
the server's host controller. When all the split URBs are completed,
stub driver reassembles the URBs into a single return command and
sends it to vhci.

Moreover, in the situation where vhci supports SG, but stub driver
does not, or vice versa, usbip works normally. Because there is no
protocol modification, there is no problem in communication between
server and client even if the one has a kernel without SG support.

In the case of vhci supports SG and stub driver doesn't, because
vhci sends only the total length of the buffer to stub driver as
it did before the patch applied, stub driver only needs to allocate
the required length of buffers using only kmalloc() regardless of
whether vhci supports SG or not. But stub driver has to allocate
buffer with kmalloc() as much as the total length of SG buffer which
is quite huge when vhci sends SG request, so it has overhead in
buffer allocation in this situation.

If stub driver needs to send data buffer to vhci because of IN pipe,
stub driver also sends only total length of buffer as metadata and
then sends real data as vhci does. Then vhci receive data from stub
driver and store it to the corresponding buffer of SG list entry.

And for the case of stub driver supports SG and vhci doesn't, since
the USB storage driver checks that vhci doesn't support SG and sends
the request to stub driver by splitting the SG list into multiple
URBs, stub driver allocates a buffer for each URB with kmalloc() as
it did before this patch.

* Test environment

Test uses two difference machines and two different kernel version
to make mismatch situation between the client and the server where
vhci supports SG, but stub driver does not, or vice versa. All tests
are conducted in both full SG support that both vhci and stub support
SG and half SG support that is the mismatch situation. Test kernel
version is 5.3-rc6 with commit "usb: add a HCD_DMA flag instead of
guestimating DMA capabilities" to avoid unnecessary DMA mapping and
unmapping.

 - Test kernel version
    - 5.3-rc6 with SG support
    - 5.1.20-200.fc29.x86_64 without SG support

* SG support test

 - Test devices
    - Super-speed storage device - SanDisk Ultra USB 3.0
    - High-speed storage device - SMI corporation USB 2.0 flash drive

 - Test description

Test read and write operation of mass storage device that uses the
BULK transfer. In test, the client reads and writes files whose size
is over 1G and it works normally.

* Regression test

 - Test devices
    - Super-speed device - Logitech Brio webcam
    - High-speed device  - Logitech C920 HD Pro webcam
    - Full-speed device  - Logitech bluetooth mouse
                         - Britz BR-Orion speaker
    - Low-speed device   - Logitech wired mouse

 - Test description

Moving and click test for mouse. To test the webcam, use gnome-cheese.
To test the speaker, play music and video on the client. All works
normally.

* VUDC compatibility test

VUDC also works well with this patch. Tests are done with two USB
gadget created by CONFIGFS USB gadget. Both use the BULK pipe.

        1. Serial gadget
        2. Mass storage gadget

 - Serial gadget test

Serial gadget on the host sends and receives data using cat command
on the /dev/ttyGS&lt;N&gt;. The client uses minicom to communicate with
the serial gadget.

 - Mass storage gadget test

After connecting the gadget with vhci, use "dd" to test read and
write operation on the client side.

Read  - dd if=/dev/sd&lt;N&gt; iflag=direct of=/dev/null bs=1G count=1
Write - dd if=&lt;my file path&gt; iflag=direct of=/dev/sd&lt;N&gt; bs=1G count=1

Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20190828032741.12234-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There are bugs on vhci with usb 3.0 storage device. In USB, each SG
list entry buffer should be divisible by the bulk max packet size.
But with native SG support, this problem doesn't matter because the
SG buffer is treated as contiguous buffer. But without native SG
support, USB storage driver breaks SG list into several URBs and the
error occurs because of a buffer size of URB that cannot be divided
by the bulk max packet size. The error situation is as follows.

When USB Storage driver requests 31.5 KB data and has SG list which
has 3584 bytes buffer followed by 7 4096 bytes buffer for some
reason. USB Storage driver splits this SG list into several URBs
because VHCI doesn't support SG and sends them separately. So the
first URB buffer size is 3584 bytes. When receiving data from device,
USB 3.0 device sends data packet of 1024 bytes size because the max
packet size of BULK pipe is 1024 bytes. So device sends 4096 bytes.
But the first URB buffer has only 3584 bytes buffer size. So host
controller terminates the transfer even though there is more data to
receive. So, vhci needs to support SG transfer to prevent this error.

In this patch, vhci supports SG regardless of whether the server's
host controller supports SG or not, because stub driver splits SG
list into several URBs if the server's host controller doesn't
support SG.

To support SG, vhci sets URB_DMA_MAP_SG flag in urb-&gt;transfer_flags
if URB has SG list and this flag will tell stub driver to use SG
list. After receiving urb from stub driver, vhci clear URB_DMA_MAP_SG
flag to avoid unnecessary DMA unmapping in HCD.

vhci sends each SG list entry to stub driver. Then, stub driver sees
the total length of the buffer and allocates SG table and pages
according to the total buffer length calling sgl_alloc(). After stub
driver receives completed URB, it again sends each SG list entry to
vhci.

If the server's host controller doesn't support SG, stub driver
breaks a single SG request into several URBs and submits them to
the server's host controller. When all the split URBs are completed,
stub driver reassembles the URBs into a single return command and
sends it to vhci.

Moreover, in the situation where vhci supports SG, but stub driver
does not, or vice versa, usbip works normally. Because there is no
protocol modification, there is no problem in communication between
server and client even if the one has a kernel without SG support.

In the case of vhci supports SG and stub driver doesn't, because
vhci sends only the total length of the buffer to stub driver as
it did before the patch applied, stub driver only needs to allocate
the required length of buffers using only kmalloc() regardless of
whether vhci supports SG or not. But stub driver has to allocate
buffer with kmalloc() as much as the total length of SG buffer which
is quite huge when vhci sends SG request, so it has overhead in
buffer allocation in this situation.

If stub driver needs to send data buffer to vhci because of IN pipe,
stub driver also sends only total length of buffer as metadata and
then sends real data as vhci does. Then vhci receive data from stub
driver and store it to the corresponding buffer of SG list entry.

And for the case of stub driver supports SG and vhci doesn't, since
the USB storage driver checks that vhci doesn't support SG and sends
the request to stub driver by splitting the SG list into multiple
URBs, stub driver allocates a buffer for each URB with kmalloc() as
it did before this patch.

* Test environment

Test uses two difference machines and two different kernel version
to make mismatch situation between the client and the server where
vhci supports SG, but stub driver does not, or vice versa. All tests
are conducted in both full SG support that both vhci and stub support
SG and half SG support that is the mismatch situation. Test kernel
version is 5.3-rc6 with commit "usb: add a HCD_DMA flag instead of
guestimating DMA capabilities" to avoid unnecessary DMA mapping and
unmapping.

 - Test kernel version
    - 5.3-rc6 with SG support
    - 5.1.20-200.fc29.x86_64 without SG support

* SG support test

 - Test devices
    - Super-speed storage device - SanDisk Ultra USB 3.0
    - High-speed storage device - SMI corporation USB 2.0 flash drive

 - Test description

Test read and write operation of mass storage device that uses the
BULK transfer. In test, the client reads and writes files whose size
is over 1G and it works normally.

* Regression test

 - Test devices
    - Super-speed device - Logitech Brio webcam
    - High-speed device  - Logitech C920 HD Pro webcam
    - Full-speed device  - Logitech bluetooth mouse
                         - Britz BR-Orion speaker
    - Low-speed device   - Logitech wired mouse

 - Test description

Moving and click test for mouse. To test the webcam, use gnome-cheese.
To test the speaker, play music and video on the client. All works
normally.

* VUDC compatibility test

VUDC also works well with this patch. Tests are done with two USB
gadget created by CONFIGFS USB gadget. Both use the BULK pipe.

        1. Serial gadget
        2. Mass storage gadget

 - Serial gadget test

Serial gadget on the host sends and receives data using cat command
on the /dev/ttyGS&lt;N&gt;. The client uses minicom to communicate with
the serial gadget.

 - Mass storage gadget test

After connecting the gadget with vhci, use "dd" to test read and
write operation on the client side.

Read  - dd if=/dev/sd&lt;N&gt; iflag=direct of=/dev/null bs=1G count=1
Write - dd if=&lt;my file path&gt; iflag=direct of=/dev/sd&lt;N&gt; bs=1G count=1

Signed-off-by: Suwan Kim &lt;suwan.kim027@gmail.com&gt;
Acked-by: Shuah khan &lt;skhan@linuxfoundation.org&gt;
Link: https://lore.kernel.org/r/20190828032741.12234-1-suwan.kim027@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
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