This patch enhances the renesas_soc_init function in
drivers/soc/renesas/renesas-soc.c by adding error handling for the
of_property_read_string call. Previously, the function did not check
for failure cases of of_property_read_string, which could lead to
improper behavior if the required device tree properties were missing
or incorrect.
Although the error addressed by this patch may not occur in the current
environment, I still suggest implementing these error handling routines
if the function is not highly time-sensitive. As the environment evolves
or the code gets reused in different contexts, there's a possibility that
these errors might occur. Addressing them now can prevent potential
debugging efforts in the future, which could be quite resource-intensive.
Signed-off-by: Haoran Liu <[email protected]>
---
drivers/soc/renesas/renesas-soc.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/soc/renesas/renesas-soc.c b/drivers/soc/renesas/renesas-soc.c
index c732d4a5b26a..7a5f5c426118 100644
--- a/drivers/soc/renesas/renesas-soc.c
+++ b/drivers/soc/renesas/renesas-soc.c
@@ -487,7 +487,13 @@ static int __init renesas_soc_init(void)
}
np = of_find_node_by_path("/");
- of_property_read_string(np, "model", &soc_dev_attr->machine);
+ ret = of_property_read_string(np, "model", &soc_dev_attr->machine);
+ if (ret) {
+ dev_err(dev, "Failed to read model property: %d\n", ret);
+ kfree(soc_dev_attr);
+ return ret;
+ }
+
of_node_put(np);
soc_dev_attr->family = kstrdup_const(family->name, GFP_KERNEL);
--
2.17.1
Hi Haoran,
kernel test robot noticed the following build errors:
[auto build test ERROR on geert-renesas-devel/next]
[also build test ERROR on linus/master v6.7-rc3 next-20231129]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Haoran-Liu/renesas-soc-Add-error-handling-in-renesas_soc_init/20231129-225113
base: https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-devel.git next
patch link: https://lore.kernel.org/r/20231129143431.34459-1-liuhaoran14%40163.com
patch subject: [PATCH] [soc/renesas] renesas-soc: Add error handling in renesas_soc_init
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20231130/[email protected]/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231130/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> drivers/soc/renesas/renesas-soc.c:492:11: error: use of undeclared identifier 'dev'
492 | dev_err(dev, "Failed to read model property: %d\n", ret);
| ^
1 error generated.
vim +/dev +492 drivers/soc/renesas/renesas-soc.c
447
448 static int __init renesas_soc_init(void)
449 {
450 struct soc_device_attribute *soc_dev_attr;
451 unsigned int product, eshi = 0, eslo;
452 const struct renesas_family *family;
453 const struct of_device_id *match;
454 const struct renesas_soc *soc;
455 const struct renesas_id *id;
456 void __iomem *chipid = NULL;
457 const char *rev_prefix = "";
458 struct soc_device *soc_dev;
459 struct device_node *np;
460 const char *soc_id;
461 int ret;
462
463 match = of_match_node(renesas_socs, of_root);
464 if (!match)
465 return -ENODEV;
466
467 soc_id = strchr(match->compatible, ',') + 1;
468 soc = match->data;
469 family = soc->family;
470
471 np = of_find_matching_node_and_match(NULL, renesas_ids, &match);
472 if (np) {
473 id = match->data;
474 chipid = of_iomap(np, 0);
475 of_node_put(np);
476 } else if (soc->id && family->reg) {
477 /* Try hardcoded CCCR/PRR fallback */
478 id = &id_prr;
479 chipid = ioremap(family->reg, 4);
480 }
481
482 soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
483 if (!soc_dev_attr) {
484 if (chipid)
485 iounmap(chipid);
486 return -ENOMEM;
487 }
488
489 np = of_find_node_by_path("/");
490 ret = of_property_read_string(np, "model", &soc_dev_attr->machine);
491 if (ret) {
> 492 dev_err(dev, "Failed to read model property: %d\n", ret);
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Haoran,
Thanks for your patch!
On Wed, Nov 29, 2023 at 3:34 PM Haoran Liu <[email protected]> wrote:
> This patch enhances the renesas_soc_init function in
> drivers/soc/renesas/renesas-soc.c by adding error handling for the
> of_property_read_string call. Previously, the function did not check
> for failure cases of of_property_read_string, which could lead to
> improper behavior if the required device tree properties were missing
Which improper behavior did you encounter? All of the
soc_device_attribute fields are optional, and drivers/base/soc.c
considers that when handling the machine field (sysfs_emit() handles
NULL pointer strings fine).
> or incorrect.
FTR, "model" is a required property of the root node.
> Although the error addressed by this patch may not occur in the current
> environment, I still suggest implementing these error handling routines
> if the function is not highly time-sensitive. As the environment evolves
> or the code gets reused in different contexts, there's a possibility that
> these errors might occur. Addressing them now can prevent potential
> debugging efforts in the future, which could be quite resource-intensive.
>
> Signed-off-by: Haoran Liu <[email protected]>
> --- a/drivers/soc/renesas/renesas-soc.c
> +++ b/drivers/soc/renesas/renesas-soc.c
> @@ -487,7 +487,13 @@ static int __init renesas_soc_init(void)
> }
>
> np = of_find_node_by_path("/");
> - of_property_read_string(np, "model", &soc_dev_attr->machine);
> + ret = of_property_read_string(np, "model", &soc_dev_attr->machine);
> + if (ret) {
> + dev_err(dev, "Failed to read model property: %d\n", ret);
As reported by the kernel test robot:
error: use of undeclared identifier 'dev'
Please do not submit completely untested patches.
> + kfree(soc_dev_attr);
> + return ret;
As the machine field is optional, there is no need for this check,
let alone to make this a fatal error condition.
> + }
> +
> of_node_put(np);
>
> soc_dev_attr->family = kstrdup_const(family->name, GFP_KERNEL);
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
Hi Haoran,
kernel test robot noticed the following build errors:
[auto build test ERROR on geert-renesas-devel/next]
[also build test ERROR on linus/master v6.7-rc3 next-20231201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Haoran-Liu/renesas-soc-Add-error-handling-in-renesas_soc_init/20231129-225113
base: https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-devel.git next
patch link: https://lore.kernel.org/r/20231129143431.34459-1-liuhaoran14%40163.com
patch subject: [PATCH] [soc/renesas] renesas-soc: Add error handling in renesas_soc_init
config: openrisc-allyesconfig (https://download.01.org/0day-ci/archive/20231201/[email protected]/config)
compiler: or1k-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231201/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
In file included from include/linux/device.h:15,
from include/linux/sys_soc.h:9,
from drivers/soc/renesas/renesas-soc.c:13:
drivers/soc/renesas/renesas-soc.c: In function 'renesas_soc_init':
>> drivers/soc/renesas/renesas-soc.c:492:25: error: 'dev' undeclared (first use in this function); did you mean 'cdev'?
492 | dev_err(dev, "Failed to read model property: %d\n", ret);
| ^~~
include/linux/dev_printk.h:110:25: note: in definition of macro 'dev_printk_index_wrap'
110 | _p_func(dev, fmt, ##__VA_ARGS__); \
| ^~~
drivers/soc/renesas/renesas-soc.c:492:17: note: in expansion of macro 'dev_err'
492 | dev_err(dev, "Failed to read model property: %d\n", ret);
| ^~~~~~~
drivers/soc/renesas/renesas-soc.c:492:25: note: each undeclared identifier is reported only once for each function it appears in
492 | dev_err(dev, "Failed to read model property: %d\n", ret);
| ^~~
include/linux/dev_printk.h:110:25: note: in definition of macro 'dev_printk_index_wrap'
110 | _p_func(dev, fmt, ##__VA_ARGS__); \
| ^~~
drivers/soc/renesas/renesas-soc.c:492:17: note: in expansion of macro 'dev_err'
492 | dev_err(dev, "Failed to read model property: %d\n", ret);
| ^~~~~~~
vim +492 drivers/soc/renesas/renesas-soc.c
447
448 static int __init renesas_soc_init(void)
449 {
450 struct soc_device_attribute *soc_dev_attr;
451 unsigned int product, eshi = 0, eslo;
452 const struct renesas_family *family;
453 const struct of_device_id *match;
454 const struct renesas_soc *soc;
455 const struct renesas_id *id;
456 void __iomem *chipid = NULL;
457 const char *rev_prefix = "";
458 struct soc_device *soc_dev;
459 struct device_node *np;
460 const char *soc_id;
461 int ret;
462
463 match = of_match_node(renesas_socs, of_root);
464 if (!match)
465 return -ENODEV;
466
467 soc_id = strchr(match->compatible, ',') + 1;
468 soc = match->data;
469 family = soc->family;
470
471 np = of_find_matching_node_and_match(NULL, renesas_ids, &match);
472 if (np) {
473 id = match->data;
474 chipid = of_iomap(np, 0);
475 of_node_put(np);
476 } else if (soc->id && family->reg) {
477 /* Try hardcoded CCCR/PRR fallback */
478 id = &id_prr;
479 chipid = ioremap(family->reg, 4);
480 }
481
482 soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
483 if (!soc_dev_attr) {
484 if (chipid)
485 iounmap(chipid);
486 return -ENOMEM;
487 }
488
489 np = of_find_node_by_path("/");
490 ret = of_property_read_string(np, "model", &soc_dev_attr->machine);
491 if (ret) {
> 492 dev_err(dev, "Failed to read model property: %d\n", ret);
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki