Re:[PATCH] bus: mhi: host: pci_generic: Fix the physical function check

"Slark Xiao" <[email protected]> Wed, 27 May 2026 18:08:23 +0800 (CST)
Newsgroups dev.linux.lists.mhi,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
At 2026-05-27 16:52:20, "Manivannan Sadhasivam" <[email protected]> wrote:
>Commit b4d01c5b9a9d ("bus: mhi: host: pci_generic: Read SUBSYSTEM_VENDOR_ID
>for VF's to check status") added the check for physical function by
>checking for 'pdev->is_physfn. But 'pdev->is_physfn' is only set for the
>physical function of a SR-IOV capable device. But for the non-SR-IOV device
>this variable will be 0. So this check ended up breaking the health check
>functionality for all non-SR-IOV devices.
>
>Fix it by checking for '!pdev->is_virtfn' to make sure that the check is
>only skipped for virtual functions.
>
>Reported-by: Slark Xiao <[email protected]>
>Fixes: b4d01c5b9a9d ("bus: mhi: host: pci_generic: Read SUBSYSTEM_VENDOR_ID for VF's to check status")
>Signed-off-by: Manivannan Sadhasivam <[email protected]>
>---
> drivers/bus/mhi/host/pci_generic.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
>diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
>index 5836ecb0ea32..0d0d9c7ffa4b 100644
>--- a/drivers/bus/mhi/host/pci_generic.c
>+++ b/drivers/bus/mhi/host/pci_generic.c
>@@ -1261,7 +1261,7 @@ static void mhi_pci_recovery_work(struct work_struct *work)
> 
> 	dev_warn(&pdev->dev, "device recovery started\n");
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		timer_delete(&mhi_pdev->health_check_timer);
> 
> 	pm_runtime_forbid(&pdev->dev);
>@@ -1291,7 +1291,7 @@ static void mhi_pci_recovery_work(struct work_struct *work)
> 
> 	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
> 
> 	return;
>@@ -1382,7 +1382,7 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> 		mhi_cntrl_config = info->config;
> 
> 	/* Initialize health check monitor only for Physical functions */
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		timer_setup(&mhi_pdev->health_check_timer, health_check, 0);
> 
> 	mhi_cntrl = &mhi_pdev->mhi_cntrl;
>@@ -1404,7 +1404,7 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> 	mhi_cntrl->mru = info->mru_default;
> 	mhi_cntrl->name = info->name;
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		mhi_pdev->reset_on_remove = info->reset_on_remove;
> 
> 	if (info->edl_trigger)
>@@ -1453,7 +1453,7 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> 	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
> 
> 	/* start health check */
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
> 
> 	/* Allow runtime suspend only if both PME from D3Hot and M3 are supported */
>@@ -1482,7 +1482,7 @@ static void mhi_pci_remove(struct pci_dev *pdev)
> 	pm_runtime_forbid(&pdev->dev);
> 	pci_disable_sriov(pdev);
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		timer_delete_sync(&mhi_pdev->health_check_timer);
> 	cancel_work_sync(&mhi_pdev->recovery_work);
> 
>@@ -1514,7 +1514,7 @@ static void mhi_pci_reset_prepare(struct pci_dev *pdev)
> 
> 	dev_info(&pdev->dev, "reset\n");
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		timer_delete(&mhi_pdev->health_check_timer);
> 
> 	/* Clean up MHI state */
>@@ -1560,7 +1560,7 @@ static void mhi_pci_reset_done(struct pci_dev *pdev)
> 	}
> 
> 	set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status);
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
> }
> 
>@@ -1626,7 +1626,7 @@ static int  __maybe_unused mhi_pci_runtime_suspend(struct device *dev)
> 	if (test_and_set_bit(MHI_PCI_DEV_SUSPENDED, &mhi_pdev->status))
> 		return 0;
> 
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		timer_delete(&mhi_pdev->health_check_timer);
> 
> 	cancel_work_sync(&mhi_pdev->recovery_work);
>@@ -1679,7 +1679,7 @@ static int __maybe_unused mhi_pci_runtime_resume(struct device *dev)
> 	}
> 
> 	/* Resume health check */
>-	if (pdev->is_physfn)
>+	if (!pdev->is_virtfn)
> 		mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
> 
> 	/* It can be a remote wakeup (no mhi runtime_get), update access time */
>-- 
>2.51.0

Tested-by: Slark Xiao <[email protected]>

Test result is expected now with these changes.
BTW, shall we add this changes into stable version? Since kernel 6.18 and 7.0  have been affected.

Thanks