From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- drivers/usb/host/ehci-sysfs.c | 168 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 168 insertions(+) create mode 100644 drivers/usb/host/ehci-sysfs.c (limited to 'drivers/usb/host/ehci-sysfs.c') diff --git a/drivers/usb/host/ehci-sysfs.c b/drivers/usb/host/ehci-sysfs.c new file mode 100644 index 000000000..5e6b545c3 --- /dev/null +++ b/drivers/usb/host/ehci-sysfs.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2007 by Alan Stern + */ + +/* this file is part of ehci-hcd.c */ + + +/* Display the ports dedicated to the companion controller */ +static ssize_t companion_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ehci_hcd *ehci; + int nports, index; + int len = 0; + + ehci = hcd_to_ehci(dev_get_drvdata(dev)); + nports = HCS_N_PORTS(ehci->hcs_params); + + for (index = 0; index < nports; ++index) { + if (test_bit(index, &ehci->companion_ports)) + len += sysfs_emit_at(buf, len, "%d\n", index + 1); + } + return len; +} + +/* + * Dedicate or undedicate a port to the companion controller. + * Syntax is "[-]portnum", where a leading '-' sign means + * return control of the port to the EHCI controller. + */ +static ssize_t companion_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ehci_hcd *ehci; + int portnum, new_owner; + + ehci = hcd_to_ehci(dev_get_drvdata(dev)); + new_owner = PORT_OWNER; /* Owned by companion */ + if (sscanf(buf, "%d", &portnum) != 1) + return -EINVAL; + if (portnum < 0) { + portnum = - portnum; + new_owner = 0; /* Owned by EHCI */ + } + if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params)) + return -ENOENT; + portnum--; + if (new_owner) + set_bit(portnum, &ehci->companion_ports); + else + clear_bit(portnum, &ehci->companion_ports); + set_owner(ehci, portnum, new_owner); + return count; +} +static DEVICE_ATTR_RW(companion); + + +/* + * Display / Set uframe_periodic_max + */ +static ssize_t uframe_periodic_max_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ehci_hcd *ehci; + + ehci = hcd_to_ehci(dev_get_drvdata(dev)); + return sysfs_emit(buf, "%d\n", ehci->uframe_periodic_max); +} + + +static ssize_t uframe_periodic_max_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ehci_hcd *ehci; + unsigned uframe_periodic_max; + unsigned uframe; + unsigned long flags; + ssize_t ret; + + ehci = hcd_to_ehci(dev_get_drvdata(dev)); + if (kstrtouint(buf, 0, &uframe_periodic_max) < 0) + return -EINVAL; + + if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) { + ehci_info(ehci, "rejecting invalid request for " + "uframe_periodic_max=%u\n", uframe_periodic_max); + return -EINVAL; + } + + ret = -EINVAL; + + /* + * lock, so that our checking does not race with possible periodic + * bandwidth allocation through submitting new urbs. + */ + spin_lock_irqsave (&ehci->lock, flags); + + /* + * for request to decrease max periodic bandwidth, we have to check + * to see whether the decrease is possible. + */ + if (uframe_periodic_max < ehci->uframe_periodic_max) { + u8 allocated_max = 0; + + for (uframe = 0; uframe < EHCI_BANDWIDTH_SIZE; ++uframe) + allocated_max = max(allocated_max, + ehci->bandwidth[uframe]); + + if (allocated_max > uframe_periodic_max) { + ehci_info(ehci, + "cannot decrease uframe_periodic_max because " + "periodic bandwidth is already allocated " + "(%u > %u)\n", + allocated_max, uframe_periodic_max); + goto out_unlock; + } + } + + /* increasing is always ok */ + + ehci_info(ehci, "setting max periodic bandwidth to %u%% " + "(== %u usec/uframe)\n", + 100*uframe_periodic_max/125, uframe_periodic_max); + + if (uframe_periodic_max != 100) + ehci_warn(ehci, "max periodic bandwidth set is non-standard\n"); + + ehci->uframe_periodic_max = uframe_periodic_max; + ret = count; + +out_unlock: + spin_unlock_irqrestore (&ehci->lock, flags); + return ret; +} +static DEVICE_ATTR_RW(uframe_periodic_max); + + +static inline int create_sysfs_files(struct ehci_hcd *ehci) +{ + struct device *controller = ehci_to_hcd(ehci)->self.controller; + int i = 0; + + /* with integrated TT there is no companion! */ + if (!ehci_is_TDI(ehci)) + i = device_create_file(controller, &dev_attr_companion); + if (i) + goto out; + + i = device_create_file(controller, &dev_attr_uframe_periodic_max); +out: + return i; +} + +static inline void remove_sysfs_files(struct ehci_hcd *ehci) +{ + struct device *controller = ehci_to_hcd(ehci)->self.controller; + + /* with integrated TT there is no companion! */ + if (!ehci_is_TDI(ehci)) + device_remove_file(controller, &dev_attr_companion); + + device_remove_file(controller, &dev_attr_uframe_periodic_max); +} -- cgit v1.3.1