2015-08-03 06:07:03

by Tomer Barletz

Subject: [PATCH] Check return code from pdc20621_i2c_read()

The variable spd0 might be used uninitialized when pdc20621_i2c_read()
fails.
This also generates a compilation warning with gcc 5.1.

Signed-off-by: Tomer Barletz <[email protected]>
---
drivers/ata/sata_sx4.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/ata/sata_sx4.c b/drivers/ata/sata_sx4.c
index 3a18a8a..070b272 100644
--- a/drivers/ata/sata_sx4.c
+++ b/drivers/ata/sata_sx4.c
@@ -1238,8 +1238,11 @@ static unsigned int pdc20621_prog_dimm_global(struct ata_host *host)
readl(mmio + PDC_SDRAM_CONTROL);

/* Turn on for ECC */
- pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
- PDC_DIMM_SPD_TYPE, &spd0);
+ if (!pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
+ PDC_DIMM_SPD_TYPE, &spd0)) {
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n", PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);
+ return 1;
+ }
if (spd0 == 0x02) {
data |= (0x01 << 16);
writel(data, mmio + PDC_SDRAM_CONTROL);
@@ -1380,8 +1383,11 @@ static unsigned int pdc20621_dimm_init(struct ata_host *host)

/* ECC initiliazation. */

- pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
- PDC_DIMM_SPD_TYPE, &spd0);
+ if (!pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
+ PDC_DIMM_SPD_TYPE, &spd0)) {
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n", PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);
+ return 1;
+ }
if (spd0 == 0x02) {
void *buf;
VPRINTK("Start ECC initialization\n");
--
2.4.3

2015-08-03 15:40:06

by Sergei Shtylyov

Subject: Re: [PATCH] Check return code from pdc20621_i2c_read()

Hello.

On 08/03/2015 09:06 AM, Tomer Barletz wrote:

> The variable spd0 might be used uninitialized when pdc20621_i2c_read()
> fails.
> This also generates a compilation warning with gcc 5.1.

> Signed-off-by: Tomer Barletz <[email protected]>
> ---
> drivers/ata/sata_sx4.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)

> diff --git a/drivers/ata/sata_sx4.c b/drivers/ata/sata_sx4.c
> index 3a18a8a..070b272 100644
> --- a/drivers/ata/sata_sx4.c
> +++ b/drivers/ata/sata_sx4.c
> @@ -1238,8 +1238,11 @@ static unsigned int pdc20621_prog_dimm_global(struct ata_host *host)
> readl(mmio + PDC_SDRAM_CONTROL);
>
> /* Turn on for ECC */
> - pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
> - PDC_DIMM_SPD_TYPE, &spd0);
> + if (!pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
> + PDC_DIMM_SPD_TYPE, &spd0)) {
> + printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n", PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);
> + return 1;
> + }
> if (spd0 == 0x02) {
> data |= (0x01 << 16);
> writel(data, mmio + PDC_SDRAM_CONTROL);
> @@ -1380,8 +1383,11 @@ static unsigned int pdc20621_dimm_init(struct ata_host *host)
>
> /* ECC initiliazation. */
>
> - pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
> - PDC_DIMM_SPD_TYPE, &spd0);
> + if (!pdc20621_i2c_read(host, PDC_DIMM0_SPD_DEV_ADDRESS,
> + PDC_DIMM_SPD_TYPE, &spd0)) {
> + printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n", PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);
> + return 1;
> + }
> if (spd0 == 0x02) {
> void *buf;
> VPRINTK("Start ECC initialization\n");

$ scripts/checkpatch.pl ~/patches/Check-return-code-from-pdc20621_i2c_read.patch
ERROR: code indent should use tabs where possible
#23: FILE: drivers/ata/sata_sx4.c:1242:
+^I PDC_DIMM_SPD_TYPE, &spd0)) {$

WARNING: line over 80 characters
#24: FILE: drivers/ata/sata_sx4.c:1243:
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n",
PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);

WARNING: Prefer [subsystem eg: netdev]_err([subsystem]dev, ... then
dev_err(dev, ... then pr_err(... to printk(KERN_ERR ...
#24: FILE: drivers/ata/sata_sx4.c:1243:
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n",
PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);

ERROR: code indent should use tabs where possible
#37: FILE: drivers/ata/sata_sx4.c:1387:
+^I PDC_DIMM_SPD_TYPE, &spd0)) {$

WARNING: line over 80 characters
#38: FILE: drivers/ata/sata_sx4.c:1388:
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n",
PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);

WARNING: Prefer [subsystem eg: netdev]_err([subsystem]dev, ... then
dev_err(dev, ... then pr_err(... to printk(KERN_ERR ...
#38: FILE: drivers/ata/sata_sx4.c:1388:
+ printk(KERN_ERR "Failed in i2c read: device=%#x, subaddr=%#x\n",
PDC_DIMM0_SPD_DEV_ADDRESS, PDC_DIMM_SPD_TYPE);

total: 2 errors, 4 warnings, 26 lines checked

NOTE: Whitespace errors detected.
You may wish to use scripts/cleanpatch or scripts/cleanfile

/home/headless/patches/Check-return-code-from-pdc20621_i2c_read.patch has
style problems, please review.

NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

MBR, Sergei