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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KYsAxXCstZBrVVF1uI2yvTNFeS0THzO9LIS1reiv5/Cl1IYAbPDqTwppdJXV?= =?us-ascii?Q?fEifdl7PZTlPpZDJe6hntHOvMYN1s3pU9qccFMvNVQUga/H5fuLU7dS8sUG4?= =?us-ascii?Q?x+U55azK6bu/8wcYU+aa+GCdfcbaHEMzaHQeWQfulA1JwqPAUaeh5tLiokXg?= =?us-ascii?Q?tGh7Gy8yKJutopOS6R5N4Z8BvsW+UuPPgYZyK/ZlPo91jivmxW5iBkry3seC?= =?us-ascii?Q?zhjiNI9Tw7Rjfmnv4zNHWjp35gQTV7QgmwBs0xekOXEuJReKPI0yJ20G8Tep?= =?us-ascii?Q?GzVyleaXebP8tfEDb14jlVCsDhJ1Bdb06q4HyhxK+GK0e+iGdYp0j/1MwlTD?= =?us-ascii?Q?g4bLlBA6QFrcTA4CZ1Xzbt5w7OP7rWwu+G33HIDGdBXnK9yP3Uu5YSJjdWfh?= =?us-ascii?Q?ruCTfRLJpAbGq5qhEdCG3KXGUTmbV2lUFKni14UkIac5ayu68RQf2IC0PViE?= =?us-ascii?Q?orTgPaC0r6JfuJcMXHFXDTLthSi7WtCE9s7zlk13wIKhRYGzNgMS1xSuUT1n?= =?us-ascii?Q?gxV3mevgJO9gNKV9feaiV36uKgkWwDi6dRSs4Cn8kezVnoIarAGcax51BIFG?= =?us-ascii?Q?6O3CzKJkh4loEJHwPJeyAU/GCRGwRAoe9vssGVnSro74m3eKhfWov949XM8i?= =?us-ascii?Q?VEsl8d6Zd2pS7sCxgnDFx+O4dp3hFyBCv6YpxaQnA3DfxTpBQJR4W1dbJr15?= =?us-ascii?Q?W+KuAvn7WgqOIGQY2AemRSNMYNCxErbN1hs1ubR0h3+dcsqn47hIPwjDA+eO?= =?us-ascii?Q?gUjlVeZ7fYVcqGgYMjK0/WFW7sIQlVHkdY1MniY5nLlr2iOWvbtVGht+Jd3C?= =?us-ascii?Q?ioez+HiQ8cT6LuMb96Sl9LuVGJdsrL5xw5KSG+60HJiTIJgcci7EyT3juGGo?= =?us-ascii?Q?Qa5Hm63LHCTMC+n8M3MkiOKsBCuFoWUUQxHXX3xNE/0f76pQ9PUHBhaTrqYF?= =?us-ascii?Q?AnvqjYBqaEmaKe12XEmLaDJjrSL0uei7q0evioO+IG38ETNkM479cUrkyGUb?= =?us-ascii?Q?64vtsPmDZMyx4Y1vrI3avXh7iJ79V9MJynTYWd1OXO8EYZuG7R4DqnZ++nnq?= =?us-ascii?Q?k8B7Ul967U604MUHH8vAjx8+r2cD7jO4XJCHIQdkNcpPRJXiBMDXi9oe2dKf?= =?us-ascii?Q?WeS7hWzHzk2vS7QWL3FdefxIWpjRgyf320AFPqm5EgkGHRyppVjGh3ym7s+M?= =?us-ascii?Q?LVn5tHdeWFF8oIC+UDnly/7XXLkYZWs7cBfdX1xRCkIzdR9wznIh43zR2Gui?= =?us-ascii?Q?G1yDjhHz+HXg2ecErD7fjNPua4kUN0jzRra/FmkY9XNiGZNSvySI3Pkn/F9s?= =?us-ascii?Q?Q1mbUctJblhjc1zGd0H96UiEeOR1wBsf68DMvVBAWHu35mIk155JSxZ7kKq9?= =?us-ascii?Q?puUX8CgS7BeAikiMp9ethfOnG1GIs0BngIM1an+P0mriABvY4BD24kPggnwC?= =?us-ascii?Q?ZtS/ZqDPKpQ3dVm5+3J3hZjE7RCZx2funHvu+BFRYvhVsqbc5RfawYWDTPIS?= =?us-ascii?Q?GURGma9wkx2GwcQ9FGse+wIFivQe347alZgfEE2k02VjCemJpM6LSXNK8Ery?= =?us-ascii?Q?CEdTb6i77pK+QYo24Hbfh+gboLAf/D+t9rb3zZ4Y?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2e9b7659-b1d5-4470-e595-08de32ae27d4 X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6373.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Dec 2025 20:54:30.9018 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: q4p6N28gqjBHeIqlff6RRIGE047kXCqaWt8iESXh6rwu07/WTumPzfjhmOG6Mlpn2FpIWd2QmaBbRgD/Thh5mQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYYPR12MB8923 On Fri, Nov 14, 2025 at 07:57:46PM +0000, Steven Noonan wrote: > We should be checking the `smn_exclusive` flag before anything else, > because that indicates whether we got through `amd_smn_init` > successfully. > > Without this change, we dereference `amd_roots` even though it may not > be allocated. > > Signed-off-by: Steven Noonan > Signed-off-by: Ariadne Conill > CC: Yazen Ghannam > CC: x86@vger.kernel.org > CC: stable@vger.kernel.org Same feedback here as for patch 1. > --- > arch/x86/kernel/amd_node.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kernel/amd_node.c b/arch/x86/kernel/amd_node.c > index cdc6ba224d4ad..919932339f4a2 100644 > --- a/arch/x86/kernel/amd_node.c > +++ b/arch/x86/kernel/amd_node.c > @@ -88,6 +88,9 @@ static int __amd_smn_rw(u8 i_off, u8 d_off, u16 node, u32 address, u32 *value, b > struct pci_dev *root; > int err = -ENODEV; > > + if (!smn_exclusive) > + return err; > + > if (node >= amd_num_nodes()) > return err; > > @@ -95,9 +98,6 @@ static int __amd_s > mn_rw(u8 i_off, u8 d_off, u16 node, u32 address, u32 *value, b > if (!root) > return err; > > - if (!smn_exclusive) > - return err; > - > guard(mutex)(&smn_mutex); > > err = pci_write_config_dword(root, i_off, address); > -- This change looks good. Did you encounter a NULL pointer dereference? Or did you find this by code inspection? Thanks, Yazen