USB: uas: Reduce can_queue to MAX_CMNDS

Orabug: 23331130

[ Upstream commit 55ff8cfbc4e12a7d2187df523938cc671fbebdd1 ]

The uas driver can never queue more then MAX_CMNDS (- 1) tags and tags
are shared between luns, so there is no need to claim that we can_queue
some random large number.

Not claiming that we can_queue 65536 commands, fixes the uas driver
failing to initialize while allocating the tag map with a "Page allocation
failure (order 7)" error on systems which have been running for a while
and thus have fragmented memory.

Cc: stable@vger.kernel.org
Reported-and-tested-by: Yves-Alexis Perez <corsac@corsac.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
(cherry picked from commit 0b914b30c534502d1d6a68a5859ee65c3d7d8aa5)

Signed-off-by: Dan Duval <dan.duval@oracle.com>

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 6d3122afeed33e9cfe1b571c3acaf19dac967da4..a5984ab9c513566343a7c31154c00b15ce3b3d28 100644 (file)
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -808,7 +808,7 @@ static struct scsi_host_template uas_host_template = {
        .slave_configure = uas_slave_configure,
        .eh_abort_handler = uas_eh_abort_handler,
        .eh_bus_reset_handler = uas_eh_bus_reset_handler,
-       .can_queue = 65536,     /* Is there a limit on the _host_ ? */
+       .can_queue = MAX_CMNDS,
        .this_id = -1,
        .sg_tablesize = SG_NONE,
        .cmd_per_lun = 1,       /* until we override it */