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

From: Slark Xiao

Date: Wed May 27 2026 - 06:15:32 EST


At 2026-05-27 16:52:20, "Manivannan Sadhasivam" <manivannan.sadhasivam@xxxxxxxxxxxxxxxx> 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 <slark_xiao@xxxxxxx>
>Fixes: b4d01c5b9a9d ("bus: mhi: host: pci_generic: Read SUBSYSTEM_VENDOR_ID for VF's to check status")
>Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
>---
> 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 <slark_xiao@xxxxxxx>

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