fsl_qspi_get_seqid() may return -EINVAL, but fsl_qspi_init_ahb_read()
doesn't check for error codes with the result that -EINVAL could find
itself signalled over the bus.
In conjunction with the LS1046A SoC's A-009283 errata
("Illegal accesses to SPI flash memory can result in a system hang")
this illegal access to SPI flash memory results in a system hang
if userspace attempts reading later on.
Avoid this by always checking fsl_qspi_get_seqid()'s return value
and bail out otherwise.
Fixes: e46ecda764 ("mtd: spi-nor: Add Freescale QuadSPI driver")
Cc: stable@vger.kernel.org
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
0004122763