s390/qdio: don't touch the dsci in tiqdio_add_input_queues()
authorJulian Wiedmann <jwi@linux.ibm.com>
Tue, 18 Jun 2019 11:12:20 +0000 (13:12 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 21 Jul 2019 07:06:08 +0000 (09:06 +0200)
commit2aa57f707fe9f187bd731475c1ec85147afc5bdb
tree3f8f19d03e7c10f65a5cf20edbb1e51df28eaa44
parent355dbc42bfb47a9033d740b69c1ea4dcfbe009f8
s390/qdio: don't touch the dsci in tiqdio_add_input_queues()

commit ac6639cd3db607d386616487902b4cc1850a7be5 upstream.

Current code sets the dsci to 0x00000080. Which doesn't make any sense,
as the indicator area is located in the _left-most_ byte.

Worse: if the dsci is the _shared_ indicator, this potentially clears
the indication of activity for a _different_ device.
tiqdio_thinint_handler() will then have no reason to call that device's
IRQ handler, and the device ends up stalling.

Fixes: d0c9d4a89fff ("[S390] qdio: set correct bit in dsci")
Cc: <stable@vger.kernel.org>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/s390/cio/qdio_thinint.c