History

Merge tag 'x86-urgent-2025-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar: - Fix AMD PCI root device caching regression that triggers on certain firmware variants - Fix the zen5_rdseed_microcode[] array to be NULL-terminated - Add more AMD models to microcode signature checking * tag 'x86-urgent-2025-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/AMD: Add more known models to entry sign checking x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode x86/amd_node: Fix AMD root device caching

Linus Torvalds committed 1 year ago

Commit 0d7bee12 parents b5c0946 d23550e4 files · +54 −100Browse files

Unified · Split

4 files
  1. arch/x86/include/asm/amd/node.h +0 −1
  2. arch/x86/kernel/amd_node.c +51 −99
  3. arch/x86/kernel/cpu/amd.c +1 −0
  4. arch/x86/kernel/cpu/microcode/amd.c +2 −0
arch/x86/include/asm/amd/node.h+0−1
@@ -23,7 +23,6 @@ · 22 unmodified lines
2323 #define AMD_NODE0_PCI_SLOT 0x18
2424
2525 struct pci_dev *amd_node_get_func(u16 node, u8 func);
26−struct pci_dev *amd_node_get_root(u16 node);
2726
2827 static inline u16 amd_num_nodes(void)
2928 {
arch/x86/kernel/amd_node.c+51−99
@@ -34,62 +34,6 @@ struct pci_dev *amd_node_get_func(u16 node, u8 func) · 33 unmodified lines
3434 return pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(AMD_NODE0_PCI_SLOT + node, func));
3535 }
3636
37−#define DF_BLK_INST_CNT 0x040
38−#define DF_CFG_ADDR_CNTL_LEGACY 0x084
39−#define DF_CFG_ADDR_CNTL_DF4 0xC04
40−
41−#define DF_MAJOR_REVISION GENMASK(27, 24)
42−
43−static u16 get_cfg_addr_cntl_offset(struct pci_dev *df_f0)
44−{
45− u32 reg;
46−
47− /*
48− * Revision fields added for DF4 and later.
49− *
50− * Major revision of '0' is found pre-DF4. Field is Read-as-Zero.
51− */
52− if (pci_read_config_dword(df_f0, DF_BLK_INST_CNT, &reg))
53− return 0;
54−
55− if (reg & DF_MAJOR_REVISION)
56− return DF_CFG_ADDR_CNTL_DF4;
57−
58− return DF_CFG_ADDR_CNTL_LEGACY;
59−}
60−
61−struct pci_dev *amd_node_get_root(u16 node)
62−{
63− struct pci_dev *root;
64− u16 cntl_off;
65− u8 bus;
66−
67− if (!cpu_feature_enabled(X86_FEATURE_ZEN))
68− return NULL;
69−
70− /*
71− * D18F0xXXX [Config Address Control] (DF::CfgAddressCntl)
72− * Bits [7:0] (SecBusNum) holds the bus number of the root device for
73− * this Data Fabric instance. The segment, device, and function will be 0.
74− */
75− struct pci_dev *df_f0 __free(pci_dev_put) = amd_node_get_func(node, 0);
76− if (!df_f0)
77− return NULL;
78−
79− cntl_off = get_cfg_addr_cntl_offset(df_f0);
80− if (!cntl_off)
81− return NULL;
82−
83− if (pci_read_config_byte(df_f0, cntl_off, &bus))
84− return NULL;
85−
86− /* Grab the pointer for the actual root device instance. */
87− root = pci_get_domain_bus_and_slot(0, bus, 0);
88−
89− pci_dbg(root, "is root for AMD node %u\n", node);
90− return root;
91−}
92−
9337 static struct pci_dev **amd_roots;
9438
9539 /* Protect the PCI config register pairs used for SMN. */
@@ -274,51 +218,21 @@ DEFINE_SHOW_STORE_ATTRIBUTE(smn_node); · 178 unmodified lines
274218 DEFINE_SHOW_STORE_ATTRIBUTE(smn_address);
275219 DEFINE_SHOW_STORE_ATTRIBUTE(smn_value);
276220
277−static int amd_cache_roots(void)
278−{
279− u16 node, num_nodes = amd_num_nodes();
280−
281− amd_roots = kcalloc(num_nodes, sizeof(*amd_roots), GFP_KERNEL);
282− if (!amd_roots)
283− return -ENOMEM;
284−
285− for (node = 0; node < num_nodes; node++)
286− amd_roots[node] = amd_node_get_root(node);
287−
288− return 0;
289−}
290−
291−static int reserve_root_config_spaces(void)
221+static struct pci_dev *get_next_root(struct pci_dev *root)
292222 {
293− struct pci_dev *root = NULL;
294− struct pci_bus *bus = NULL;
295−
296− while ((bus = pci_find_next_bus(bus))) {
297− /* Root device is Device 0 Function 0 on each Primary Bus. */
298− root = pci_get_slot(bus, 0);
299− if (!root)
223+ while ((root = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, root))) {
224+ /* Root device is Device 0 Function 0. */
225+ if (root->devfn)
300226 continue;
301227
302228 if (root->vendor != PCI_VENDOR_ID_AMD &&
303229 root->vendor != PCI_VENDOR_ID_HYGON)
304230 continue;
305231
306− pci_dbg(root, "Reserving PCI config space\n");
307−
308− /*
309− * There are a few SMN index/data pairs and other registers
310− * that shouldn't be accessed by user space.
311− * So reserve the entire PCI config space for simplicity rather
312− * than covering specific registers piecemeal.
313− */
314− if (!pci_request_config_region_exclusive(root, 0, PCI_CFG_SPACE_SIZE, NULL)) {
315− pci_err(root, "Failed to reserve config space\n");
316− return -EEXIST;
317− }
232+ break;
318233 }
319234
320− smn_exclusive = true;
321− return 0;
235+ return root;
322236 }
323237
324238 static bool enable_dfs;
@@ -332,7 +246,8 @@ __setup("amd_smn_debugfs_enable", amd_smn_enable_dfs); · 7 unmodified lines
332246
333247 static int __init amd_smn_init(void)
334248 {
335− int err;
249+ u16 count, num_roots, roots_per_node, node, num_nodes;
250+ struct pci_dev *root;
336251
337252 if (!cpu_feature_enabled(X86_FEATURE_ZEN))
338253 return 0;
@@ -342,13 +257,48 @@ static int __init amd_smn_init(void) · 3 unmodified lines
342257 if (amd_roots)
343258 return 0;
344259
345− err = amd_cache_roots();
346− if (err)
347− return err;
260+ num_roots = 0;
261+ root = NULL;
262+ while ((root = get_next_root(root))) {
263+ pci_dbg(root, "Reserving PCI config space\n");
348264
349− err = reserve_root_config_spaces();
350− if (err)
351− return err;
265+ /*
266+ * There are a few SMN index/data pairs and other registers
267+ * that shouldn't be accessed by user space. So reserve the
268+ * entire PCI config space for simplicity rather than covering
269+ * specific registers piecemeal.
270+ */
271+ if (!pci_request_config_region_exclusive(root, 0, PCI_CFG_SPACE_SIZE, NULL)) {
272+ pci_err(root, "Failed to reserve config space\n");
273+ return -EEXIST;
274+ }
275+
276+ num_roots++;
277+ }
278+
279+ pr_debug("Found %d AMD root devices\n", num_roots);
280+
281+ if (!num_roots)
282+ return -ENODEV;
283+
284+ num_nodes = amd_num_nodes();
285+ amd_roots = kcalloc(num_nodes, sizeof(*amd_roots), GFP_KERNEL);
286+ if (!amd_roots)
287+ return -ENOMEM;
288+
289+ roots_per_node = num_roots / num_nodes;
290+
291+ count = 0;
292+ node = 0;
293+ root = NULL;
294+ while (node < num_nodes && (root = get_next_root(root))) {
295+ /* Use one root for each node and skip the rest. */
296+ if (count++ % roots_per_node)
297+ continue;
298+
299+ pci_dbg(root, "is root for AMD node %u\n", node);
300+ amd_roots[node++] = root;
301+ }
352302
353303 if (enable_dfs) {
354304 debugfs_dir = debugfs_create_dir("amd_smn", arch_debugfs_dir);
@@ -358,6 +308,8 @@ static int __init amd_smn_init(void) · 3 unmodified lines
358308 debugfs_create_file("value", 0600, debugfs_dir, NULL, &smn_value_fops);
359309 }
360310
311+ smn_exclusive = true;
312+
361313 return 0;
362314 }
363315
arch/x86/kernel/cpu/amd.c+1−0
@@ -1038,6 +1038,7 @@ static void init_amd_zen4(struct cpuinfo_x86 *c) · 1037 unmodified lines
10381038 static const struct x86_cpu_id zen5_rdseed_microcode[] = {
10391039 ZEN_MODEL_STEP_UCODE(0x1a, 0x02, 0x1, 0x0b00215a),
10401040 ZEN_MODEL_STEP_UCODE(0x1a, 0x11, 0x0, 0x0b101054),
1041+ {},
10411042 };
10421043
10431044 static void init_amd_zen5(struct cpuinfo_x86 *c)
arch/x86/kernel/cpu/microcode/amd.c+2−0
@@ -220,10 +220,12 @@ static bool need_sha_check(u32 cur_rev) · 219 unmodified lines
220220 case 0xaa001: return cur_rev <= 0xaa00116; break;
221221 case 0xaa002: return cur_rev <= 0xaa00218; break;
222222 case 0xb0021: return cur_rev <= 0xb002146; break;
223+ case 0xb0081: return cur_rev <= 0xb008111; break;
223224 case 0xb1010: return cur_rev <= 0xb101046; break;
224225 case 0xb2040: return cur_rev <= 0xb204031; break;
225226 case 0xb4040: return cur_rev <= 0xb404031; break;
226227 case 0xb6000: return cur_rev <= 0xb600031; break;
228+ case 0xb6080: return cur_rev <= 0xb608031; break;
227229 case 0xb7000: return cur_rev <= 0xb700031; break;
228230 default: break;
229231 }