| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <aQJGlOIJBY+44Q0v@lizhi-Precision-Tower-5810>
Date: Wed, 29 Oct 2025 12:53:40 -0400
From: Frank Li <Frank.li@....com>
To: Koichiro Den <den@...inux.co.jp>
Cc: ntb@...ts.linux.dev, linux-pci@...r.kernel.org,
linux-kernel@...r.kernel.org, jdmason@...zu.us,
dave.jiang@...el.com, allenbh@...il.com, mani@...nel.org,
kwilczynski@...nel.org, kishon@...nel.org, bhelgaas@...gle.com,
jbrunet@...libre.com, lpieralisi@...nel.org, yebin10@...wei.com,
geert+renesas@...der.be, arnd@...db.de
Subject: Re: [PATCH v2 6/6] PCI: endpoint: pci-epf-vntb: manage ntb_dev
lifetime and fix vpci bus teardown
On Wed, Oct 29, 2025 at 05:03:21PM +0900, Koichiro Den wrote:
> Currently ntb_dev is embedded in epf_ntb, while configfs allows starting
> or stopping controller and linking or unlinking functions as you want.
> In fact, re-linking and re-starting is not possible with the embedded
> design and leads to oopses.
>
> Allocate ntb_dev with devm and add a .remove callback to the pci driver
> that calls ntb_unregister_device(). This allows a fresh device to be
> created on the next .bind call.
>
> With these changes, the controller can now be stopped, a function
> unlinked, configfs settings updated, and the controller re-linked and
> restarted without rebooting the endpoint, as long as the underlying
> pci_epc_ops .stop() operation is non-destructive, and .start() can
> restore normal operations.
>
> Signed-off-by: Koichiro Den <den@...inux.co.jp>
> ---
> drivers/pci/endpoint/functions/pci-epf-vntb.c | 66 +++++++++++++++----
> 1 file changed, 52 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 750a246f79c9..3059ed85a955 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -118,7 +118,7 @@ struct epf_ntb_ctrl {
> } __packed;
>
> struct epf_ntb {
> - struct ntb_dev ntb;
> + struct ntb_dev *ntb;
> struct pci_epf *epf;
> struct config_group group;
>
> @@ -144,10 +144,16 @@ struct epf_ntb {
> void __iomem *vpci_mw_addr[MAX_MW];
>
> struct delayed_work cmd_handler;
> +
> + struct pci_bus *vpci_bus;
> };
>
> #define to_epf_ntb(epf_group) container_of((epf_group), struct epf_ntb, group)
> -#define ntb_ndev(__ntb) container_of(__ntb, struct epf_ntb, ntb)
> +
> +static inline struct epf_ntb *ntb_ndev(struct ntb_dev *ntb)
> +{
> + return (struct epf_ntb *)ntb->pdev->sysdata;
> +}
>
> static struct pci_epf_header epf_ntb_header = {
> .vendorid = PCI_ANY_ID,
> @@ -173,7 +179,7 @@ static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
> else
> ntb->reg->link_status &= ~LINK_STATUS_UP;
>
> - ntb_link_event(&ntb->ntb);
> + ntb_link_event(ntb->ntb);
> return 0;
> }
>
> @@ -261,7 +267,7 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
> for (i = 1; i < ntb->db_count; i++) {
> if (ntb->epf_db[i]) {
> ntb->db |= 1 << (i - 1);
> - ntb_db_event(&ntb->ntb, i);
> + ntb_db_event(ntb->ntb, i);
> ntb->epf_db[i] = 0;
> }
> }
> @@ -1097,12 +1103,24 @@ static int vpci_scan_bus(void *sysdata)
> {
> struct pci_bus *vpci_bus;
> struct epf_ntb *ndev = sysdata;
> -
> - vpci_bus = pci_scan_bus(ndev->vbus_number, &vpci_ops, sysdata);
> + LIST_HEAD(resources);
> + static struct resource busn_res = {
> + .start = 0,
> + .end = 255,
> + .flags = IORESOURCE_BUS,
> + };
> +
> + pci_add_resource(&resources, &ioport_resource);
> + pci_add_resource(&resources, &iomem_resource);
> + pci_add_resource(&resources, &busn_res);
> +
> + vpci_bus = pci_scan_root_bus(&ndev->epf->epc->dev, ndev->vbus_number,
> + &vpci_ops, sysdata, &resources);
look this part is not belong to this patch. just change API
pci_scan_bus() to pci_scan_root_bus()?
Frank
> if (!vpci_bus) {
> pr_err("create pci bus failed\n");
> return -EINVAL;
> }
> + ndev->vpci_bus = vpci_bus;
>
> pci_bus_add_devices(vpci_bus);
>
> @@ -1147,7 +1165,7 @@ static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx,
> int ret;
> struct device *dev;
>
> - dev = &ntb->ntb.dev;
> + dev = &ntb->ntb->dev;
> barno = ntb->epf_ntb_bar[BAR_MW1 + idx];
> epf_bar = &ntb->epf->bar[barno];
> epf_bar->phys_addr = addr;
> @@ -1247,7 +1265,7 @@ static int vntb_epf_peer_db_set(struct ntb_dev *ndev, u64 db_bits)
> ret = pci_epc_raise_irq(ntb->epf->epc, func_no, vfunc_no,
> PCI_IRQ_MSI, interrupt_num + 1);
> if (ret)
> - dev_err(&ntb->ntb.dev, "Failed to raise IRQ\n");
> + dev_err(&ntb->ntb->dev, "Failed to raise IRQ\n");
>
> return ret;
> }
> @@ -1334,9 +1352,12 @@ static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> struct epf_ntb *ndev = (struct epf_ntb *)pdev->sysdata;
> struct device *dev = &pdev->dev;
>
> - ndev->ntb.pdev = pdev;
> - ndev->ntb.topo = NTB_TOPO_NONE;
> - ndev->ntb.ops = &vntb_epf_ops;
> + ndev->ntb = devm_kzalloc(dev, sizeof(*ndev->ntb), GFP_KERNEL);
> + if (!ndev->ntb)
> + return -ENOMEM;
> + ndev->ntb->pdev = pdev;
> + ndev->ntb->topo = NTB_TOPO_NONE;
> + ndev->ntb->ops = &vntb_epf_ops;
>
> ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
> if (ret) {
> @@ -1344,7 +1365,7 @@ static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> return ret;
> }
>
> - ret = ntb_register_device(&ndev->ntb);
> + ret = ntb_register_device(ndev->ntb);
> if (ret) {
> dev_err(dev, "Failed to register NTB device\n");
> return ret;
> @@ -1354,6 +1375,17 @@ static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> return 0;
> }
>
> +static void pci_vntb_remove(struct pci_dev *pdev)
> +{
> + struct epf_ntb *ndev = (struct epf_ntb *)pdev->sysdata;
> +
> + if (!ndev || !ndev->ntb)
> + return;
> +
> + ntb_unregister_device(ndev->ntb);
> + ndev->ntb = NULL;
> +}
> +
> static struct pci_device_id pci_vntb_table[] = {
> {
> PCI_DEVICE(0xffff, 0xffff),
> @@ -1365,6 +1397,7 @@ static struct pci_driver vntb_pci_driver = {
> .name = "pci-vntb",
> .id_table = pci_vntb_table,
> .probe = pci_vntb_probe,
> + .remove = pci_vntb_remove,
> };
>
> /* ============ PCIe EPF Driver Bind ====================*/
> @@ -1447,10 +1480,15 @@ static void epf_ntb_unbind(struct pci_epf *epf)
> {
> struct epf_ntb *ntb = epf_get_drvdata(epf);
>
> + pci_unregister_driver(&vntb_pci_driver);
> +
> + pci_lock_rescan_remove();
> + pci_stop_root_bus(ntb->vpci_bus);
> + pci_remove_root_bus(ntb->vpci_bus);
> + pci_unlock_rescan_remove();
> +
> epf_ntb_epc_cleanup(ntb);
> epf_ntb_config_spad_bar_free(ntb);
> -
> - pci_unregister_driver(&vntb_pci_driver);
> }
>
> // EPF driver probe
> --
> 2.48.1
>
Powered by blists - more mailing lists