Merge tag 'x86-urgent-2025-03-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull more x86 fixes from Ingo Molnar:

 - Add more model IDs to the AMD microcode version check, more people
   are hitting these checks

 - Fix a Xen guest boot warning related to AMD northbridge setup

 - Fix SEV guest bugs related to a recent changes in its locking logic

 - Fix a missing definition of PTRS_PER_PMD that assembly builds can hit

* tag 'x86-urgent-2025-03-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add some forgotten models to the SHA check
  x86/mm: Define PTRS_PER_PMD for assembly code too
  virt: sev-guest: Move SNP Guest Request data pages handling under snp_cmd_mutex
  virt: sev-guest: Allocate request data dynamically
  x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range()

Author: torvalds

arch/x86/coco/sev/core.c

@@ -2853,19 +2853,8 @@ struct snp_msg_desc *snp_msg_alloc(void)
 	if (!mdesc->response)
 		goto e_free_request;
 
-	mdesc->certs_data = alloc_shared_pages(SEV_FW_BLOB_MAX_SIZE);
-	if (!mdesc->certs_data)
-		goto e_free_response;
-
-	/* initial the input address for guest request */
-	mdesc->input.req_gpa = __pa(mdesc->request);
-	mdesc->input.resp_gpa = __pa(mdesc->response);
-	mdesc->input.data_gpa = __pa(mdesc->certs_data);
-
 	return mdesc;
 
-e_free_response:
-	free_shared_pages(mdesc->response, sizeof(struct snp_guest_msg));
 e_free_request:
 	free_shared_pages(mdesc->request, sizeof(struct snp_guest_msg));
 e_unmap:
@@ -2885,7 +2874,6 @@ void snp_msg_free(struct snp_msg_desc *mdesc)
 	kfree(mdesc->ctx);
 	free_shared_pages(mdesc->response, sizeof(struct snp_guest_msg));
 	free_shared_pages(mdesc->request, sizeof(struct snp_guest_msg));
-	free_shared_pages(mdesc->certs_data, SEV_FW_BLOB_MAX_SIZE);
 	iounmap((__force void __iomem *)mdesc->secrets);
 
 	memset(mdesc, 0, sizeof(*mdesc));
@@ -3054,7 +3042,7 @@ static int __handle_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_r
 	 * sequence number must be incremented or the VMPCK must be deleted to
 	 * prevent reuse of the IV.
 	 */
-	rc = snp_issue_guest_request(req, &mdesc->input, rio);
+	rc = snp_issue_guest_request(req, &req->input, rio);
 	switch (rc) {
 	case -ENOSPC:
 		/*
@@ -3064,7 +3052,7 @@ static int __handle_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_r
 		 * order to increment the sequence number and thus avoid
 		 * IV reuse.
 		 */
-		override_npages = mdesc->input.data_npages;
+		override_npages = req->input.data_npages;
 		req->exit_code	= SVM_VMGEXIT_GUEST_REQUEST;
 
 		/*
@@ -3120,7 +3108,7 @@ static int __handle_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_r
 	}
 
 	if (override_npages)
-		mdesc->input.data_npages = override_npages;
+		req->input.data_npages = override_npages;
 
 	return rc;
 }
@@ -3158,6 +3146,11 @@ int snp_send_guest_request(struct snp_msg_desc *mdesc, struct snp_guest_req *req
 	 */
 	memcpy(mdesc->request, &mdesc->secret_request, sizeof(mdesc->secret_request));
 
+	/* Initialize the input address for guest request */
+	req->input.req_gpa = __pa(mdesc->request);
+	req->input.resp_gpa = __pa(mdesc->response);
+	req->input.data_gpa = req->certs_data ? __pa(req->certs_data) : 0;
+
 	rc = __handle_guest_request(mdesc, req, rio);
 	if (rc) {
 		if (rc == -EIO &&

arch/x86/include/asm/pgtable-2level_types.h

@@ -23,17 +23,17 @@ typedef union {
 #define ARCH_PAGE_TABLE_SYNC_MASK	PGTBL_PMD_MODIFIED
 
 /*
- * traditional i386 two-level paging structure:
+ * Traditional i386 two-level paging structure:
  */
 
 #define PGDIR_SHIFT	22
 #define PTRS_PER_PGD	1024
 
-
 /*
- * the i386 is two-level, so we don't really have any
- * PMD directory physically.
+ * The i386 is two-level, so we don't really have any
+ * PMD directory physically:
  */
+#define PTRS_PER_PMD	1
 
 #define PTRS_PER_PTE	1024
 

arch/x86/include/asm/sev.h

@@ -203,6 +203,9 @@ struct snp_guest_req {
 	unsigned int vmpck_id;
 	u8 msg_version;
 	u8 msg_type;
+
+	struct snp_req_data input;
+	void *certs_data;
 };
 
 /*
@@ -263,9 +266,6 @@ struct snp_msg_desc {
 	struct snp_guest_msg secret_request, secret_response;
 
 	struct snp_secrets_page *secrets;
-	struct snp_req_data input;
-
-	void *certs_data;
 
 	struct aesgcm_ctx *ctx;
 

arch/x86/kernel/amd_nb.c

@@ -143,21 +143,18 @@ bool __init early_is_amd_nb(u32 device)
 
 struct resource *amd_get_mmconfig_range(struct resource *res)
 {
-	u32 address;
 	u64 base, msr;
 	unsigned int segn_busn_bits;
 
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
 		return NULL;
 
-	/* assume all cpus from fam10h have mmconfig */
-	if (boot_cpu_data.x86 < 0x10)
+	/* Assume CPUs from Fam10h have mmconfig, although not all VMs do */
+	if (boot_cpu_data.x86 < 0x10 ||
+	    rdmsrl_safe(MSR_FAM10H_MMIO_CONF_BASE, &msr))
 		return NULL;
 
-	address = MSR_FAM10H_MMIO_CONF_BASE;
-	rdmsrl(address, msr);
-
 	/* mmconfig is not enabled */
 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
 		return NULL;

arch/x86/kernel/cpu/microcode/amd.c

@@ -175,23 +175,29 @@ static bool need_sha_check(u32 cur_rev)
 {
 	switch (cur_rev >> 8) {
 	case 0x80012: return cur_rev <= 0x800126f; break;
+	case 0x80082: return cur_rev <= 0x800820f; break;
 	case 0x83010: return cur_rev <= 0x830107c; break;
 	case 0x86001: return cur_rev <= 0x860010e; break;
 	case 0x86081: return cur_rev <= 0x8608108; break;
 	case 0x87010: return cur_rev <= 0x8701034; break;
 	case 0x8a000: return cur_rev <= 0x8a0000a; break;
+	case 0xa0010: return cur_rev <= 0xa00107a; break;
 	case 0xa0011: return cur_rev <= 0xa0011da; break;
 	case 0xa0012: return cur_rev <= 0xa001243; break;
+	case 0xa0082: return cur_rev <= 0xa00820e; break;
 	case 0xa1011: return cur_rev <= 0xa101153; break;
 	case 0xa1012: return cur_rev <= 0xa10124e; break;
 	case 0xa1081: return cur_rev <= 0xa108109; break;
 	case 0xa2010: return cur_rev <= 0xa20102f; break;
 	case 0xa2012: return cur_rev <= 0xa201212; break;
+	case 0xa4041: return cur_rev <= 0xa404109; break;
+	case 0xa5000: return cur_rev <= 0xa500013; break;
 	case 0xa6012: return cur_rev <= 0xa60120a; break;
 	case 0xa7041: return cur_rev <= 0xa704109; break;
 	case 0xa7052: return cur_rev <= 0xa705208; break;
 	case 0xa7080: return cur_rev <= 0xa708009; break;
 	case 0xa70c0: return cur_rev <= 0xa70C009; break;
+	case 0xaa001: return cur_rev <= 0xaa00116; break;
 	case 0xaa002: return cur_rev <= 0xaa00218; break;
 	default: break;
 	}

drivers/virt/coco/sev-guest/sev-guest.c

@@ -38,12 +38,6 @@ struct snp_guest_dev {
 	struct miscdevice misc;
 
 	struct snp_msg_desc *msg_desc;
-
-	union {
-		struct snp_report_req report;
-		struct snp_derived_key_req derived_key;
-		struct snp_ext_report_req ext_report;
-	} req;
 };
 
 /*
@@ -71,7 +65,7 @@ struct snp_req_resp {
 
 static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg)
 {
-	struct snp_report_req *report_req = &snp_dev->req.report;
+	struct snp_report_req *report_req __free(kfree) = NULL;
 	struct snp_msg_desc *mdesc = snp_dev->msg_desc;
 	struct snp_report_resp *report_resp;
 	struct snp_guest_req req = {};
@@ -80,6 +74,10 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io
 	if (!arg->req_data || !arg->resp_data)
 		return -EINVAL;
 
+	report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT);
+	if (!report_req)
+		return -ENOMEM;
+
 	if (copy_from_user(report_req, (void __user *)arg->req_data, sizeof(*report_req)))
 		return -EFAULT;
 
@@ -116,7 +114,7 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io
 
 static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg)
 {
-	struct snp_derived_key_req *derived_key_req = &snp_dev->req.derived_key;
+	struct snp_derived_key_req *derived_key_req __free(kfree) = NULL;
 	struct snp_derived_key_resp derived_key_resp = {0};
 	struct snp_msg_desc *mdesc = snp_dev->msg_desc;
 	struct snp_guest_req req = {};
@@ -136,6 +134,10 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque
 	if (sizeof(buf) < resp_len)
 		return -ENOMEM;
 
+	derived_key_req = kzalloc(sizeof(*derived_key_req), GFP_KERNEL_ACCOUNT);
+	if (!derived_key_req)
+		return -ENOMEM;
+
 	if (copy_from_user(derived_key_req, (void __user *)arg->req_data,
 			   sizeof(*derived_key_req)))
 		return -EFAULT;
@@ -168,16 +170,21 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 			  struct snp_req_resp *io)
 
 {
-	struct snp_ext_report_req *report_req = &snp_dev->req.ext_report;
+	struct snp_ext_report_req *report_req __free(kfree) = NULL;
 	struct snp_msg_desc *mdesc = snp_dev->msg_desc;
 	struct snp_report_resp *report_resp;
 	struct snp_guest_req req = {};
 	int ret, npages = 0, resp_len;
 	sockptr_t certs_address;
+	struct page *page;
 
 	if (sockptr_is_null(io->req_data) || sockptr_is_null(io->resp_data))
 		return -EINVAL;
 
+	report_req = kzalloc(sizeof(*report_req), GFP_KERNEL_ACCOUNT);
+	if (!report_req)
+		return -ENOMEM;
+
 	if (copy_from_sockptr(report_req, io->req_data, sizeof(*report_req)))
 		return -EFAULT;
 
@@ -203,8 +210,20 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 	 * the host. If host does not supply any certs in it, then copy
 	 * zeros to indicate that certificate data was not provided.
 	 */
-	memset(mdesc->certs_data, 0, report_req->certs_len);
 	npages = report_req->certs_len >> PAGE_SHIFT;
+	page = alloc_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO,
+			   get_order(report_req->certs_len));
+	if (!page)
+		return -ENOMEM;
+
+	req.certs_data = page_address(page);
+	ret = set_memory_decrypted((unsigned long)req.certs_data, npages);
+	if (ret) {
+		pr_err("failed to mark page shared, ret=%d\n", ret);
+		__free_pages(page, get_order(report_req->certs_len));
+		return -EFAULT;
+	}
+
 cmd:
 	/*
 	 * The intermediate response buffer is used while decrypting the
@@ -213,10 +232,12 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 	 */
 	resp_len = sizeof(report_resp->data) + mdesc->ctx->authsize;
 	report_resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT);
-	if (!report_resp)
-		return -ENOMEM;
+	if (!report_resp) {
+		ret = -ENOMEM;
+		goto e_free_data;
+	}
 
-	mdesc->input.data_npages = npages;
+	req.input.data_npages = npages;
 
 	req.msg_version = arg->msg_version;
 	req.msg_type = SNP_MSG_REPORT_REQ;
@@ -231,7 +252,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 
 	/* If certs length is invalid then copy the returned length */
 	if (arg->vmm_error == SNP_GUEST_VMM_ERR_INVALID_LEN) {
-		report_req->certs_len = mdesc->input.data_npages << PAGE_SHIFT;
+		report_req->certs_len = req.input.data_npages << PAGE_SHIFT;
 
 		if (copy_to_sockptr(io->req_data, report_req, sizeof(*report_req)))
 			ret = -EFAULT;
@@ -240,7 +261,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 	if (ret)
 		goto e_free;
 
-	if (npages && copy_to_sockptr(certs_address, mdesc->certs_data, report_req->certs_len)) {
+	if (npages && copy_to_sockptr(certs_address, req.certs_data, report_req->certs_len)) {
 		ret = -EFAULT;
 		goto e_free;
 	}
@@ -250,6 +271,13 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques
 
 e_free:
 	kfree(report_resp);
+e_free_data:
+	if (npages) {
+		if (set_memory_encrypted((unsigned long)req.certs_data, npages))
+			WARN_ONCE(ret, "failed to restore encryption mask (leak it)\n");
+		else
+			__free_pages(page, get_order(report_req->certs_len));
+	}
 	return ret;
 }