| Message ID | 20180921093252.9115-1-a.fatoum@pengutronix.de |
|---|---|
| State | Accepted |
| Delegated to: | Boris Brezillon |
| Headers | show |
| Series | mtd: spi-nor: fsl-quadspi: Don't let -EINVAL on the bus | expand |
On Fri, 21 Sep 2018 11:32:53 +0200 Ahmad Fatoum <a.fatoum@pengutronix.de> wrote: > 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. > > Cc: stable@vger.kernel.org > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Added Fixes: e46ecda764dc ("mtd: spi-nor: Add Freescale QuadSPI driver") and queued it to spi-nor/next. Thanks, Boris > --- > drivers/mtd/spi-nor/fsl-quadspi.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c > index 7d9620c7ff6c..1bb42e40c38b 100644 > --- a/drivers/mtd/spi-nor/fsl-quadspi.c > +++ b/drivers/mtd/spi-nor/fsl-quadspi.c > @@ -543,6 +543,9 @@ fsl_qspi_runcmd(struct fsl_qspi *q, u8 cmd, unsigned int addr, int len) > > /* trigger the LUT now */ > seqid = fsl_qspi_get_seqid(q, cmd); > + if (seqid < 0) > + return seqid; > + > qspi_writel(q, (seqid << QUADSPI_IPCR_SEQID_SHIFT) | len, > base + QUADSPI_IPCR); > > @@ -671,7 +674,7 @@ static void fsl_qspi_set_map_addr(struct fsl_qspi *q) > * causes the controller to clear the buffer, and use the sequence pointed > * by the QUADSPI_BFGENCR[SEQID] to initiate a read from the flash. > */ > -static void fsl_qspi_init_ahb_read(struct fsl_qspi *q) > +static int fsl_qspi_init_ahb_read(struct fsl_qspi *q) > { > void __iomem *base = q->iobase; > int seqid; > @@ -696,8 +699,12 @@ static void fsl_qspi_init_ahb_read(struct fsl_qspi *q) > > /* Set the default lut sequence for AHB Read. */ > seqid = fsl_qspi_get_seqid(q, q->nor[0].read_opcode); > + if (seqid < 0) > + return seqid; > + > qspi_writel(q, seqid << QUADSPI_BFGENCR_SEQID_SHIFT, > q->iobase + QUADSPI_BFGENCR); > + return 0; > } > > /* This function was used to prepare and enable QSPI clock */ > @@ -805,9 +812,7 @@ static int fsl_qspi_nor_setup_last(struct fsl_qspi *q) > fsl_qspi_init_lut(q); > > /* Init for AHB read */ > - fsl_qspi_init_ahb_read(q); > - > - return 0; > + return fsl_qspi_init_ahb_read(q); > } > > static const struct of_device_id fsl_qspi_dt_ids[] = {
diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c index 7d9620c7ff6c..1bb42e40c38b 100644 --- a/drivers/mtd/spi-nor/fsl-quadspi.c +++ b/drivers/mtd/spi-nor/fsl-quadspi.c @@ -543,6 +543,9 @@ fsl_qspi_runcmd(struct fsl_qspi *q, u8 cmd, unsigned int addr, int len) /* trigger the LUT now */ seqid = fsl_qspi_get_seqid(q, cmd); + if (seqid < 0) + return seqid; + qspi_writel(q, (seqid << QUADSPI_IPCR_SEQID_SHIFT) | len, base + QUADSPI_IPCR); @@ -671,7 +674,7 @@ static void fsl_qspi_set_map_addr(struct fsl_qspi *q) * causes the controller to clear the buffer, and use the sequence pointed * by the QUADSPI_BFGENCR[SEQID] to initiate a read from the flash. */ -static void fsl_qspi_init_ahb_read(struct fsl_qspi *q) +static int fsl_qspi_init_ahb_read(struct fsl_qspi *q) { void __iomem *base = q->iobase; int seqid; @@ -696,8 +699,12 @@ static void fsl_qspi_init_ahb_read(struct fsl_qspi *q) /* Set the default lut sequence for AHB Read. */ seqid = fsl_qspi_get_seqid(q, q->nor[0].read_opcode); + if (seqid < 0) + return seqid; + qspi_writel(q, seqid << QUADSPI_BFGENCR_SEQID_SHIFT, q->iobase + QUADSPI_BFGENCR); + return 0; } /* This function was used to prepare and enable QSPI clock */ @@ -805,9 +812,7 @@ static int fsl_qspi_nor_setup_last(struct fsl_qspi *q) fsl_qspi_init_lut(q); /* Init for AHB read */ - fsl_qspi_init_ahb_read(q); - - return 0; + return fsl_qspi_init_ahb_read(q); } static const struct of_device_id fsl_qspi_dt_ids[] = {
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. Cc: stable@vger.kernel.org Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> --- drivers/mtd/spi-nor/fsl-quadspi.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)