[PATCH 1/2] mailbox: zynqmp-ipi: Fix CPU hotplug state cleanup

[PATCH 1/2] mailbox: zynqmp-ipi: Fix CPU hotplug state cleanup

[Prasanna Kumar T S M]

On driver removal, the CPUHP_AP_ONLINE_DYN CPU hotplug state is removed
instead of the its actual state. This can leave the mailbox driver
callbacks dangling. Use the actual CPU hotplug state during driver
removal.

Hotplug registration failures are also ignored, allowing probe to
succeed without the callbacks needed to enable interrupts on CPUs
brought online later.

Fixes: 6ffb1635341be ("mailbox: zynqmp: handle SGI for shared IPI")
Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
---
 drivers/mailbox/zynqmp-ipi-mailbox.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/mailbox/zynqmp-ipi-mailbox.c b/drivers/mailbox/zynqmp-ipi-mailbox.c
index 42d2583e44ca..b0643ee75db0 100644
--- a/drivers/mailbox/zynqmp-ipi-mailbox.c
+++ b/drivers/mailbox/zynqmp-ipi-mailbox.c
@@ -136,6 +136,7 @@ struct zynqmp_ipi_pdata {
 	unsigned int method;
 	u32 local_id;
 	int virq_sgi;
+	enum cpuhp_state hp_state;
 	int num_mboxes;
 	struct zynqmp_ipi_mbox ipi_mboxes[] __counted_by(num_mboxes);
 };
@@ -863,15 +864,22 @@ static int xlnx_mbox_init_sgi(struct platform_device *pdev,
 	irq_set_status_flags(pdata->virq_sgi, IRQ_PER_CPU);
 
 	/* Setup function for the CPU hot-plug cases */
-	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mailbox/sgi:starting",
-			  xlnx_mbox_cpuhp_start, xlnx_mbox_cpuhp_down);
+	pdata->hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+			  "mailbox/sgi:starting", xlnx_mbox_cpuhp_start,
+			  xlnx_mbox_cpuhp_down);
+	if (pdata->hp_state < 0) {
+		irq_clear_status_flags(pdata->virq_sgi, IRQ_PER_CPU);
+		free_percpu_irq(pdata->virq_sgi, &per_cpu_pdata);
+		irq_dispose_mapping(pdata->virq_sgi);
+		return pdata->hp_state;
+	}
 
 	return ret;
 }
 
 static void xlnx_mbox_cleanup_sgi(struct zynqmp_ipi_pdata *pdata)
 {
-	cpuhp_remove_state(CPUHP_AP_ONLINE_DYN);
+	cpuhp_remove_state(pdata->hp_state);
 
 	on_each_cpu(xlnx_disable_percpu_irq, NULL, 1);
 
-- 
2.49.0

[PATCH 2/2] soc: xilinx: Fix event manager CPU hotplug state cleanup

[Prasanna Kumar T S M]

On driver removal, the event manager removes the CPUHP_AP_ONLINE_DYN
CPU hotplug state instead of the its actual state. This can leave the
event manager callbacks dangling. Use the actual CPU hotplug state
during driver removal.

Hotplug registration failures are also ignored, allowing probe to
succeed without the callbacks needed to enable event interrupts on
CPUs brought online later.

Fixes: c7fdb2404f66 ("drivers: soc: xilinx: add xilinx event management driver")
Signed-off-by: Prasanna Kumar T S M <ptsm@linux.microsoft.com>
---
 drivers/soc/xilinx/xlnx_event_manager.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/soc/xilinx/xlnx_event_manager.c b/drivers/soc/xilinx/xlnx_event_manager.c
index f733dc42b3b1..2d8bfeab4190 100644
--- a/drivers/soc/xilinx/xlnx_event_manager.c
+++ b/drivers/soc/xilinx/xlnx_event_manager.c
@@ -24,6 +24,7 @@ static DEFINE_PER_CPU_READ_MOSTLY(int, dummy_cpu_number);
 
 static int virq_sgi;
 static int event_manager_availability = -EACCES;
+static enum cpuhp_state hp_state;
 
 /* SGI number used for Event management driver */
 #define XLNX_EVENT_SGI_NUM	(15)
@@ -625,8 +626,6 @@ static int xlnx_event_init_sgi(struct platform_device *pdev)
 
 static void xlnx_event_cleanup_sgi(struct platform_device *pdev)
 {
-	cpuhp_remove_state(CPUHP_AP_ONLINE_DYN);
-
 	on_each_cpu(xlnx_disable_percpu_irq, NULL, 1);
 
 	irq_clear_status_flags(virq_sgi, IRQ_PER_CPU);
@@ -660,8 +659,13 @@ static int xlnx_event_manager_probe(struct platform_device *pdev)
 	}
 
 	/* Setup function for the CPU hot-plug cases */
-	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "soc/event:starting",
-			  xlnx_event_cpuhp_start, xlnx_event_cpuhp_down);
+	hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+			"soc/event:starting", xlnx_event_cpuhp_start,
+			xlnx_event_cpuhp_down);
+	if (hp_state < 0) {
+		xlnx_event_cleanup_sgi(pdev);
+		return hp_state;
+	}
 
 	ret = zynqmp_pm_register_sgi(sgi_num, 0);
 	if (ret) {
@@ -670,6 +674,7 @@ static int xlnx_event_manager_probe(struct platform_device *pdev)
 		else
 			dev_err(&pdev->dev, "SGI %d registration failed, err %d\n", sgi_num, ret);
 
+		cpuhp_remove_state(hp_state);
 		xlnx_event_cleanup_sgi(pdev);
 		return ret;
 	}
@@ -704,6 +709,7 @@ static void xlnx_event_manager_remove(struct platform_device *pdev)
 	if (ret)
 		dev_err(&pdev->dev, "SGI unregistration over TF-A failed with %d\n", ret);
 
+	cpuhp_remove_state(hp_state);
 	xlnx_event_cleanup_sgi(pdev);
 
 	event_manager_availability = -EACCES;
-- 
2.49.0

Re: [PATCH 2/2] soc: xilinx: Fix event manager CPU hotplug state cleanup

[Jay Buddhabhatti]

Hi Prasanna,

On Mon, Nov 02, 2026 at 10:35:15PM -0800, Prasanna Kumar T S M wrote:
 > On driver removal, the event manager removes the CPUHP_AP_ONLINE_DYN
 > CPU hotplug state instead of the its actual state. This can leave the
 > event manager callbacks dangling. Use the actual CPU hotplug state
 > during driver removal.
 >
 > Hotplug registration failures are also ignored, allowing probe to
 > succeed without the callbacks needed to enable event interrupts on
 > CPUs brought online later.
 >
 > Fixes: c7fdb2404f66 ("drivers: soc: xilinx: add xilinx event 
management driver")
 > Signed-off-by: Prasanna Kumar T S M ptsm@linux.microsoft.com

This looks good to me.

A couple of small nits:

- "instead of the its actual state" -> "instead of its actual state"
- Minor alignment on the cpuhp_setup_state() continuation lines;
   checkpatch --strict complains.
	CHECK: Alignment should match open parenthesis
	#49: FILE: drivers/soc/xilinx/xlnx_event_manager.c:663:
	+       hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
	+                       "soc/event:starting", xlnx_event_cpuhp_start,

	total: 0 errors, 0 warnings, 1 checks, 44 lines checked

Worth Cc: stable@vger.kernel.org as well, given the Fixes tag.

Reviewed-by: Jay Buddhabhatti <jay.buddhabhatti@amd.com>

Thanks,
Jay

Re: [PATCH 2/2] soc: xilinx: Fix event manager CPU hotplug state cleanup

[Prasanna Kumar T S M]

Hi Jay,

On 03-11-2026 17:56, Jay Buddhabhatti wrote:
> Hi Prasanna,
> 
> On Mon, Nov 02, 2026 at 10:35:15PM -0800, Prasanna Kumar T S M wrote:
>  > On driver removal, the event manager removes the CPUHP_AP_ONLINE_DYN
>  > CPU hotplug state instead of the its actual state. This can leave the
>  > event manager callbacks dangling. Use the actual CPU hotplug state
>  > during driver removal.
>  >
>  > Hotplug registration failures are also ignored, allowing probe to
>  > succeed without the callbacks needed to enable event interrupts on
>  > CPUs brought online later.
>  >
>  > Fixes: c7fdb2404f66 ("drivers: soc: xilinx: add xilinx event 
> management driver")
>  > Signed-off-by: Prasanna Kumar T S M ptsm@linux.microsoft.com
> 
> This looks good to me.
> 
> A couple of small nits:
> 
> - "instead of the its actual state" -> "instead of its actual state"

Thanks for catching this.

> - Minor alignment on the cpuhp_setup_state() continuation lines;
>    checkpatch --strict complains.
>      CHECK: Alignment should match open parenthesis
>      #49: FILE: drivers/soc/xilinx/xlnx_event_manager.c:663:
>      +       hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
>      +                       "soc/event:starting", xlnx_event_cpuhp_start,
> 
>      total: 0 errors, 0 warnings, 1 checks, 44 lines checked

I missed this.

I think the issues are minor. Is it possible to fix this while merging 
the patch?

> 
> Worth Cc: stable@vger.kernel.org as well, given the Fixes tag.

Do I need to send v2 to address this?

> 
> Reviewed-by: Jay Buddhabhatti <jay.buddhabhatti@amd.com>
> 
> Thanks,
> Jay

Thanks,
Prasanna Kumar