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/sh/intc/userimask.c | 95 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 drivers/sh/intc/userimask.c (limited to 'drivers/sh/intc/userimask.c') diff --git a/drivers/sh/intc/userimask.c b/drivers/sh/intc/userimask.c new file mode 100644 index 000000000..a363f7788 --- /dev/null +++ b/drivers/sh/intc/userimask.c @@ -0,0 +1,95 @@ +/* + * Support for hardware-assisted userspace interrupt masking. + * + * Copyright (C) 2010 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#define pr_fmt(fmt) "intc: " fmt + +#include +#include +#include +#include +#include +#include +#include "internals.h" + +static void __iomem *uimask; + +static ssize_t +show_intc_userimask(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", (__raw_readl(uimask) >> 4) & 0xf); +} + +static ssize_t +store_intc_userimask(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned long level; + int ret; + + ret = kstrtoul(buf, 10, &level); + if (ret != 0) + return ret; + + /* + * Minimal acceptable IRQ levels are in the 2 - 16 range, but + * these are chomped so as to not interfere with normal IRQs. + * + * Level 1 is a special case on some CPUs in that it's not + * directly settable, but given that USERIMASK cuts off below a + * certain level, we don't care about this limitation here. + * Level 0 on the other hand equates to user masking disabled. + * + * We use the default priority level as a cut off so that only + * special case opt-in IRQs can be mangled. + */ + if (level >= intc_get_dfl_prio_level()) + return -EINVAL; + + __raw_writel(0xa5 << 24 | level << 4, uimask); + + return count; +} + +static DEVICE_ATTR(userimask, S_IRUSR | S_IWUSR, + show_intc_userimask, store_intc_userimask); + + +static int __init userimask_sysdev_init(void) +{ + struct device *dev_root; + int ret = 0; + + if (unlikely(!uimask)) + return -ENXIO; + + dev_root = bus_get_dev_root(&intc_subsys); + if (dev_root) { + ret = device_create_file(dev_root, &dev_attr_userimask); + put_device(dev_root); + } + return ret; +} +late_initcall(userimask_sysdev_init); + +int register_intc_userimask(unsigned long addr) +{ + if (unlikely(uimask)) + return -EBUSY; + + uimask = ioremap(addr, SZ_4K); + if (unlikely(!uimask)) + return -ENOMEM; + + pr_info("userimask support registered for levels 0 -> %d\n", + intc_get_dfl_prio_level() - 1); + + return 0; +} -- cgit v1.3.1