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 --- arch/alpha/lib/udelay.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 arch/alpha/lib/udelay.c (limited to 'arch/alpha/lib/udelay.c') diff --git a/arch/alpha/lib/udelay.c b/arch/alpha/lib/udelay.c new file mode 100644 index 000000000..873648263 --- /dev/null +++ b/arch/alpha/lib/udelay.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 1993, 2000 Linus Torvalds + * + * Delay routines, using a pre-computed "loops_per_jiffy" value. + */ + +#include +#include /* for udelay's use of smp_processor_id */ +#include +#include +#include + +/* + * Use only for very small delays (< 1 msec). + * + * The active part of our cycle counter is only 32-bits wide, and + * we're treating the difference between two marks as signed. On + * a 1GHz box, that's about 2 seconds. + */ + +void +__delay(int loops) +{ + int tmp; + __asm__ __volatile__( + " rpcc %0\n" + " addl %1,%0,%1\n" + "1: rpcc %0\n" + " subl %1,%0,%0\n" + " bgt %0,1b" + : "=&r" (tmp), "=r" (loops) : "1"(loops)); +} +EXPORT_SYMBOL(__delay); + +#ifdef CONFIG_SMP +#define LPJ cpu_data[smp_processor_id()].loops_per_jiffy +#else +#define LPJ loops_per_jiffy +#endif + +void +udelay(unsigned long usecs) +{ + usecs *= (((unsigned long)HZ << 32) / 1000000) * LPJ; + __delay((long)usecs >> 32); +} +EXPORT_SYMBOL(udelay); + +void +ndelay(unsigned long nsecs) +{ + nsecs *= (((unsigned long)HZ << 32) / 1000000000) * LPJ; + __delay((long)nsecs >> 32); +} +EXPORT_SYMBOL(ndelay); -- cgit v1.3.1