| Message ID | 4469eba2-188b-aab7-07d1-5c77313fc42f@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | Guard pci_create_sysfs_dev_files with atomic value | expand |
Hi, Am Montag, 29. August 2022, 21:14:43 CEST schrieb Korneliusz Osmenda: > On Gateworks Ventana there is a number of PCI devices and: > - imx6_pcie_probe takes longer than start of late init > - pci_sysfs_init sets up flag sysfs_initialized > - pci_sysfs_init initializes already found devices > - imx6_pcie_probe tries to reinitialize device > > Bug: https://bugzilla.kernel.org/show_bug.cgi?id=215515 > > Signed-off-by: Korneliusz Osmenda <korneliuszo@gmail.com> > --- > drivers/pci/pci-sysfs.c | 6 ++++++ > include/linux/pci.h | 2 ++ > 2 files changed, 8 insertions(+) > > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > index fc804e08e3cb..a6648239e235 100644 > --- a/drivers/pci/pci-sysfs.c > +++ b/drivers/pci/pci-sysfs.c > @@ -1378,6 +1378,9 @@ int __must_check pci_create_sysfs_dev_files(struct > pci_dev *pdev) > if (!sysfs_initialized) > return -EACCES; > > + if (atomic_cmpxchg(&pdev->sysfs_init_cnt,0,1) == 1) > + return 0; /* already added */ > + > return pci_create_resource_files(pdev); > } > > @@ -1392,6 +1395,9 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev) > if (!sysfs_initialized) > return; > > + if (atomic_cmpxchg(&pdev->sysfs_init_cnt,1,0) == 0) > + return; /* already removed */ > + > pci_remove_resource_files(pdev); > } > > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 060af91bafcd..5477de2ef057 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -465,6 +465,8 @@ struct pci_dev { > pci_dev_flags_t dev_flags; > atomic_t enable_cnt; /* pci_enable_device has been called */ > > + atomic_t sysfs_init_cnt; /* pci_create_sysfs_dev_files has been called */ > + > u32 saved_config_space[16]; /* Config space saved at suspend time */ > struct hlist_head saved_cap_space; > int rom_attr_enabled; /* Display of ROM attribute enabled? */ Is there any feedback here? I'm hitting the same issue on TQMa6x+MBa6x. Having this patch applied my PCIe device using several bridges is detected fine. root@tqma6-common:~# lspci 00:00.0 PCI bridge: Synopsys, Inc. DWC_usb3 / PCIe bridge (rev 01) 01:00.0 PCI bridge: Pericom Semiconductor Device a303 (rev 03) 02:01.0 PCI bridge: Pericom Semiconductor Device a303 (rev 03) 02:02.0 PCI bridge: Pericom Semiconductor Device a303 (rev 03) 03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0c) 04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0c) root@tqma6-common:~# lspci -t -[0000:00]---00.0-[01-ff]----00.0-[02-04]--+-01.0-[03]----00.0 \-02.0-[04]----00.0 Best regards, Alexander
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index fc804e08e3cb..a6648239e235 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1378,6 +1378,9 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) if (!sysfs_initialized) return -EACCES; + if (atomic_cmpxchg(&pdev->sysfs_init_cnt,0,1) == 1) + return 0; /* already added */ + return pci_create_resource_files(pdev); } @@ -1392,6 +1395,9 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev) if (!sysfs_initialized) return; + if (atomic_cmpxchg(&pdev->sysfs_init_cnt,1,0) == 0) + return; /* already removed */ + pci_remove_resource_files(pdev); } diff --git a/include/linux/pci.h b/include/linux/pci.h index 060af91bafcd..5477de2ef057 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -465,6 +465,8 @@ struct pci_dev { pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ + atomic_t sysfs_init_cnt; /* pci_create_sysfs_dev_files has been called */ + u32 saved_config_space[16]; /* Config space saved at suspend time */ struct hlist_head saved_cap_space; int rom_attr_enabled; /* Display of ROM attribute enabled? */
On Gateworks Ventana there is a number of PCI devices and: - imx6_pcie_probe takes longer than start of late init - pci_sysfs_init sets up flag sysfs_initialized - pci_sysfs_init initializes already found devices - imx6_pcie_probe tries to reinitialize device Bug: https://bugzilla.kernel.org/show_bug.cgi?id=215515 Signed-off-by: Korneliusz Osmenda <korneliuszo@gmail.com> --- drivers/pci/pci-sysfs.c | 6 ++++++ include/linux/pci.h | 2 ++ 2 files changed, 8 insertions(+)