* [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
@ 2026-04-11 2:36 Rosen Penev
2026-04-13 8:51 ` kernel test robot
2026-04-15 12:56 ` Heikki Krogerus
0 siblings, 2 replies; 4+ messages in thread
From: Rosen Penev @ 2026-04-11 2:36 UTC (permalink / raw)
To: linux-usb
Cc: Heikki Krogerus, Greg Kroah-Hartman, Kees Cook,
Gustavo A. R. Silva, open list,
open list:KERNEL HARDENING (not covered by other areas):Keyword:b__counted_by(_le|_be)?b
A flexible array member can be used to combine allocations and simplify
handling slightly.
Add __counted_by for extra runtime analysis.
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
drivers/usb/typec/mux/intel_pmc_mux.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c
index 1698428654ab..8b0a3dd3f940 100644
--- a/drivers/usb/typec/mux/intel_pmc_mux.c
+++ b/drivers/usb/typec/mux/intel_pmc_mux.c
@@ -151,13 +151,14 @@ struct pmc_usb {
u8 num_ports;
struct device *dev;
struct intel_scu_ipc_dev *ipc;
- struct pmc_usb_port *port;
struct acpi_device *iom_adev;
void __iomem *iom_base;
u32 iom_port_status_offset;
u8 iom_port_status_size;
struct dentry *dentry;
+
+ struct pmc_usb_port port[] __counted_by(num_ports);
};
static struct dentry *pmc_mux_debugfs_root;
@@ -731,27 +732,26 @@ static int pmc_usb_probe(struct platform_device *pdev)
{
struct fwnode_handle *fwnode = NULL;
struct pmc_usb *pmc;
+ u8 num_ports;
int i = 0;
int ret;
- pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL);
- if (!pmc)
- return -ENOMEM;
-
device_for_each_child_node(&pdev->dev, fwnode)
- pmc->num_ports++;
+ num_ports++;
/* The IOM microcontroller has a limitation of max 4 ports. */
- if (pmc->num_ports > 4) {
+ if (num_ports > 4) {
dev_err(&pdev->dev, "driver limited to 4 ports\n");
return -ERANGE;
}
- pmc->port = devm_kcalloc(&pdev->dev, pmc->num_ports,
- sizeof(struct pmc_usb_port), GFP_KERNEL);
- if (!pmc->port)
+ pmc = devm_kzalloc(&pdev->dev, struct_size(pmc, port, num_ports),
+ GFP_KERNEL);
+ if (!pmc)
return -ENOMEM;
+ pmc->num_ports = num_ports;
+
pmc->ipc = devm_intel_scu_ipc_dev_get(&pdev->dev);
if (!pmc->ipc)
return -EPROBE_DEFER;
--
2.53.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
2026-04-11 2:36 [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc Rosen Penev
@ 2026-04-13 8:51 ` kernel test robot
2026-04-13 19:47 ` Rosen Penev
2026-04-15 12:56 ` Heikki Krogerus
1 sibling, 1 reply; 4+ messages in thread
From: kernel test robot @ 2026-04-13 8:51 UTC (permalink / raw)
To: Rosen Penev, linux-usb
Hi Rosen,
kernel test robot noticed the following build warnings:
[auto build test WARNING on usb/usb-testing]
[also build test WARNING on usb/usb-next usb/usb-linus westeri-thunderbolt/next linus/master v7.0-rc7 next-20260410]
[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/Rosen-Penev/usb-typec-intel_pmc_mux-combine-kzalloc-kcalloc/20260412-223212
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
patch link: https://lore.kernel.org/r/20260411023642.146890-1-rosenp%40gmail.com
patch subject: [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
config: x86_64-allmodconfig (https://download.01.org/0day-ci/archive/20260413/202604131654.9GEXISW5-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260413/202604131654.9GEXISW5-lkp@intel.com/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 <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202604131654.9GEXISW5-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/usb/typec/mux/intel_pmc_mux.c:740:3: warning: variable 'num_ports' is uninitialized when used here [-Wuninitialized]
740 | num_ports++;
| ^~~~~~~~~
drivers/usb/typec/mux/intel_pmc_mux.c:735:14: note: initialize the variable 'num_ports' to silence this warning
735 | u8 num_ports;
| ^
| = '\0'
1 warning generated.
vim +/num_ports +740 drivers/usb/typec/mux/intel_pmc_mux.c
730
731 static int pmc_usb_probe(struct platform_device *pdev)
732 {
733 struct fwnode_handle *fwnode = NULL;
734 struct pmc_usb *pmc;
735 u8 num_ports;
736 int i = 0;
737 int ret;
738
739 device_for_each_child_node(&pdev->dev, fwnode)
> 740 num_ports++;
741
742 /* The IOM microcontroller has a limitation of max 4 ports. */
743 if (num_ports > 4) {
744 dev_err(&pdev->dev, "driver limited to 4 ports\n");
745 return -ERANGE;
746 }
747
748 pmc = devm_kzalloc(&pdev->dev, struct_size(pmc, port, num_ports),
749 GFP_KERNEL);
750 if (!pmc)
751 return -ENOMEM;
752
753 pmc->num_ports = num_ports;
754
755 pmc->ipc = devm_intel_scu_ipc_dev_get(&pdev->dev);
756 if (!pmc->ipc)
757 return -EPROBE_DEFER;
758
759 pmc->dev = &pdev->dev;
760
761 ret = pmc_usb_probe_iom(pmc);
762 if (ret)
763 return ret;
764
765 pmc->dentry = debugfs_create_dir(dev_name(pmc->dev), pmc_mux_debugfs_root);
766
767 /*
768 * For every physical USB connector (USB2 and USB3 combo) there is a
769 * child ACPI device node under the PMC mux ACPI device object.
770 */
771 for (i = 0; i < pmc->num_ports; i++) {
772 fwnode = device_get_next_child_node(pmc->dev, fwnode);
773 if (!fwnode)
774 break;
775
776 ret = pmc_usb_register_port(pmc, i, fwnode);
777 if (ret) {
778 fwnode_handle_put(fwnode);
779 goto err_remove_ports;
780 }
781
782 pmc_mux_port_debugfs_init(&pmc->port[i]);
783 }
784
785 platform_set_drvdata(pdev, pmc);
786
787 return 0;
788
789 err_remove_ports:
790 for (i = 0; i < pmc->num_ports; i++) {
791 typec_switch_unregister(pmc->port[i].typec_sw);
792 typec_mux_unregister(pmc->port[i].typec_mux);
793 usb_role_switch_unregister(pmc->port[i].usb_sw);
794 }
795
796 acpi_dev_put(pmc->iom_adev);
797
798 debugfs_remove(pmc->dentry);
799
800 return ret;
801 }
802
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
2026-04-13 8:51 ` kernel test robot
@ 2026-04-13 19:47 ` Rosen Penev
0 siblings, 0 replies; 4+ messages in thread
From: Rosen Penev @ 2026-04-13 19:47 UTC (permalink / raw)
To: kernel test robot; +Cc: linux-usb
On Mon, Apr 13, 2026 at 1:52 AM kernel test robot <lkp@intel.com> wrote:
>
> Hi Rosen,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on usb/usb-testing]
> [also build test WARNING on usb/usb-next usb/usb-linus westeri-thunderbolt/next linus/master v7.0-rc7 next-20260410]
> [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/Rosen-Penev/usb-typec-intel_pmc_mux-combine-kzalloc-kcalloc/20260412-223212
> base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> patch link: https://lore.kernel.org/r/20260411023642.146890-1-rosenp%40gmail.com
> patch subject: [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
> config: x86_64-allmodconfig (https://download.01.org/0day-ci/archive/20260413/202604131654.9GEXISW5-lkp@intel.com/config)
> compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260413/202604131654.9GEXISW5-lkp@intel.com/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 <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202604131654.9GEXISW5-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/usb/typec/mux/intel_pmc_mux.c:740:3: warning: variable 'num_ports' is uninitialized when used here [-Wuninitialized]
> 740 | num_ports++;
> | ^~~~~~~~~
> drivers/usb/typec/mux/intel_pmc_mux.c:735:14: note: initialize the variable 'num_ports' to silence this warning
> 735 | u8 num_ports;
> | ^
> | = '\0'
> 1 warning generated.
Yikes I forgot to do this. As the merge window is closed I assume this
needs to wait.
>
>
> vim +/num_ports +740 drivers/usb/typec/mux/intel_pmc_mux.c
>
> 730
> 731 static int pmc_usb_probe(struct platform_device *pdev)
> 732 {
> 733 struct fwnode_handle *fwnode = NULL;
> 734 struct pmc_usb *pmc;
> 735 u8 num_ports;
> 736 int i = 0;
> 737 int ret;
> 738
> 739 device_for_each_child_node(&pdev->dev, fwnode)
> > 740 num_ports++;
> 741
> 742 /* The IOM microcontroller has a limitation of max 4 ports. */
> 743 if (num_ports > 4) {
> 744 dev_err(&pdev->dev, "driver limited to 4 ports\n");
> 745 return -ERANGE;
> 746 }
> 747
> 748 pmc = devm_kzalloc(&pdev->dev, struct_size(pmc, port, num_ports),
> 749 GFP_KERNEL);
> 750 if (!pmc)
> 751 return -ENOMEM;
> 752
> 753 pmc->num_ports = num_ports;
> 754
> 755 pmc->ipc = devm_intel_scu_ipc_dev_get(&pdev->dev);
> 756 if (!pmc->ipc)
> 757 return -EPROBE_DEFER;
> 758
> 759 pmc->dev = &pdev->dev;
> 760
> 761 ret = pmc_usb_probe_iom(pmc);
> 762 if (ret)
> 763 return ret;
> 764
> 765 pmc->dentry = debugfs_create_dir(dev_name(pmc->dev), pmc_mux_debugfs_root);
> 766
> 767 /*
> 768 * For every physical USB connector (USB2 and USB3 combo) there is a
> 769 * child ACPI device node under the PMC mux ACPI device object.
> 770 */
> 771 for (i = 0; i < pmc->num_ports; i++) {
> 772 fwnode = device_get_next_child_node(pmc->dev, fwnode);
> 773 if (!fwnode)
> 774 break;
> 775
> 776 ret = pmc_usb_register_port(pmc, i, fwnode);
> 777 if (ret) {
> 778 fwnode_handle_put(fwnode);
> 779 goto err_remove_ports;
> 780 }
> 781
> 782 pmc_mux_port_debugfs_init(&pmc->port[i]);
> 783 }
> 784
> 785 platform_set_drvdata(pdev, pmc);
> 786
> 787 return 0;
> 788
> 789 err_remove_ports:
> 790 for (i = 0; i < pmc->num_ports; i++) {
> 791 typec_switch_unregister(pmc->port[i].typec_sw);
> 792 typec_mux_unregister(pmc->port[i].typec_mux);
> 793 usb_role_switch_unregister(pmc->port[i].usb_sw);
> 794 }
> 795
> 796 acpi_dev_put(pmc->iom_adev);
> 797
> 798 debugfs_remove(pmc->dentry);
> 799
> 800 return ret;
> 801 }
> 802
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc
2026-04-11 2:36 [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc Rosen Penev
2026-04-13 8:51 ` kernel test robot
@ 2026-04-15 12:56 ` Heikki Krogerus
1 sibling, 0 replies; 4+ messages in thread
From: Heikki Krogerus @ 2026-04-15 12:56 UTC (permalink / raw)
To: Rosen Penev
Cc: linux-usb, Greg Kroah-Hartman, Kees Cook, Gustavo A. R. Silva,
open list,
open list:KERNEL HARDENING (not covered by other areas):Keyword:b__counted_by(_le|_be)?b
Hi Rosen,
On Fri, Apr 10, 2026 at 07:36:42PM -0700, Rosen Penev wrote:
> A flexible array member can be used to combine allocations and simplify
> handling slightly.
>
> Add __counted_by for extra runtime analysis.
One nitpick below.
Otherwise this looks okay to me.
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
> drivers/usb/typec/mux/intel_pmc_mux.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c
> index 1698428654ab..8b0a3dd3f940 100644
> --- a/drivers/usb/typec/mux/intel_pmc_mux.c
> +++ b/drivers/usb/typec/mux/intel_pmc_mux.c
> @@ -151,13 +151,14 @@ struct pmc_usb {
> u8 num_ports;
> struct device *dev;
> struct intel_scu_ipc_dev *ipc;
> - struct pmc_usb_port *port;
> struct acpi_device *iom_adev;
> void __iomem *iom_base;
> u32 iom_port_status_offset;
> u8 iom_port_status_size;
>
> struct dentry *dentry;
> +
> + struct pmc_usb_port port[] __counted_by(num_ports);
> };
>
> static struct dentry *pmc_mux_debugfs_root;
> @@ -731,27 +732,26 @@ static int pmc_usb_probe(struct platform_device *pdev)
> {
> struct fwnode_handle *fwnode = NULL;
> struct pmc_usb *pmc;
> + u8 num_ports;
> int i = 0;
> int ret;
>
> - pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL);
> - if (!pmc)
> - return -ENOMEM;
> -
> device_for_each_child_node(&pdev->dev, fwnode)
> - pmc->num_ports++;
> + num_ports++;
>
> /* The IOM microcontroller has a limitation of max 4 ports. */
> - if (pmc->num_ports > 4) {
> + if (num_ports > 4) {
> dev_err(&pdev->dev, "driver limited to 4 ports\n");
> return -ERANGE;
> }
>
> - pmc->port = devm_kcalloc(&pdev->dev, pmc->num_ports,
> - sizeof(struct pmc_usb_port), GFP_KERNEL);
> - if (!pmc->port)
> + pmc = devm_kzalloc(&pdev->dev, struct_size(pmc, port, num_ports),
> + GFP_KERNEL);
One line is enough for that.
> + if (!pmc)
> return -ENOMEM;
>
> + pmc->num_ports = num_ports;
> +
> pmc->ipc = devm_intel_scu_ipc_dev_get(&pdev->dev);
> if (!pmc->ipc)
> return -EPROBE_DEFER;
> --
> 2.53.0
thanks,
--
heikki
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2026-04-15 12:57 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-11 2:36 [PATCH] usb: typec: intel_pmc_mux: combine kzalloc + kcalloc Rosen Penev
2026-04-13 8:51 ` kernel test robot
2026-04-13 19:47 ` Rosen Penev
2026-04-15 12:56 ` Heikki Krogerus
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox