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/arm/lib/putuser.S | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 arch/arm/lib/putuser.S (limited to 'arch/arm/lib/putuser.S') diff --git a/arch/arm/lib/putuser.S b/arch/arm/lib/putuser.S new file mode 100644 index 000000000..bdd8836dc --- /dev/null +++ b/arch/arm/lib/putuser.S @@ -0,0 +1,95 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/lib/putuser.S + * + * Copyright (C) 2001 Russell King + * + * Idea from x86 version, (C) Copyright 1998 Linus Torvalds + * + * These functions have a non-standard call interface to make + * them more efficient, especially as they return an error + * value in addition to the "real" return value. + * + * __put_user_X + * + * Inputs: r0 contains the address + * r1 contains the address limit, which must be preserved + * r2, r3 contains the value + * Outputs: r0 is the error code + * lr corrupted + * + * No other registers must be altered. (see + * for specific ASM register usage). + * + * Note that ADDR_LIMIT is either 0 or 0xc0000000 + * Note also that it is intended that __put_user_bad is not global. + */ +#include +#include +#include +#include + +ENTRY(__put_user_1) + check_uaccess r0, 1, r1, ip, __put_user_bad +1: TUSER(strb) r2, [r0] + mov r0, #0 + ret lr +ENDPROC(__put_user_1) + +ENTRY(__put_user_2) + check_uaccess r0, 2, r1, ip, __put_user_bad +#if __LINUX_ARM_ARCH__ >= 6 + +2: TUSER(strh) r2, [r0] + +#else + + mov ip, r2, lsr #8 +#ifndef __ARMEB__ +2: TUSER(strb) r2, [r0], #1 +3: TUSER(strb) ip, [r0] +#else +2: TUSER(strb) ip, [r0], #1 +3: TUSER(strb) r2, [r0] +#endif + +#endif /* __LINUX_ARM_ARCH__ >= 6 */ + mov r0, #0 + ret lr +ENDPROC(__put_user_2) + +ENTRY(__put_user_4) + check_uaccess r0, 4, r1, ip, __put_user_bad +4: TUSER(str) r2, [r0] + mov r0, #0 + ret lr +ENDPROC(__put_user_4) + +ENTRY(__put_user_8) + check_uaccess r0, 8, r1, ip, __put_user_bad +#ifdef CONFIG_THUMB2_KERNEL +5: TUSER(str) r2, [r0] +6: TUSER(str) r3, [r0, #4] +#else +5: TUSER(str) r2, [r0], #4 +6: TUSER(str) r3, [r0] +#endif + mov r0, #0 + ret lr +ENDPROC(__put_user_8) + +__put_user_bad: + mov r0, #-EFAULT + ret lr +ENDPROC(__put_user_bad) + +.pushsection __ex_table, "a" + .long 1b, __put_user_bad + .long 2b, __put_user_bad +#if __LINUX_ARM_ARCH__ < 6 + .long 3b, __put_user_bad +#endif + .long 4b, __put_user_bad + .long 5b, __put_user_bad + .long 6b, __put_user_bad +.popsection -- cgit v1.3.1