kernel/linux.git/arch, branch v7.2.3

KVM: s390: vsie: zero stale crypto bits

2026-09-02T12:33:21+00:00

commit 34d5b5b646c91cfb9338d7a12c955a70ffb8c66b upstream. When shadowing crypto access bits from a format0 apcb (crycb 0 or 1), the bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested guest potential access to a device no longer available. Zero out the remaining bits. Fixes: 6b79de4b056e ("KVM: s390: vsie: allow guest FORMAT-1 CRYCB on host FORMAT-2") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger Reviewed-by: Claudio Imbrenda Signed-off-by: Claudio Imbrenda Message-ID: <20260811153738.206885-3-borntraeger@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Wire up kvm_x86_ops.gmem_xxx() if and only if CONFIG_KVM_AMD_SEV=y

2026-09-02T12:33:18+00:00

commit 01a96ff30dde5127c37497f1e098e639e7ae152f upstream. Wire up the SEV-SNP guest_memfd kvm_x86_ops hooks if and only if SEV is actually enabled, and drop the now-unnecessary stubs. Leaving the hooks NULL allows the static call infrastructure to elide the CALL+RET, and more importantly, referencing the hooks if and only if SEV support is enabled will allow conditionally definining the hooks using their corresponding HAVE_KVM_ARCH_GMEM_XXX Kconfig. No functional change intended. Cc: stable@vger.kernel.org # 6.12.x Reviewed-by: Ackerley Tng Link: https://patch.msgid.link/20260709204948.1988414-5-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Mark vCPU RUNNABLE after AP_CREATE, even if VMSA is unusable

2026-09-02T12:33:18+00:00

commit 98ade8c48c28c227fe2e80e545ff0c57cd4712a3 upstream. Always mark the vCPU as RUNNABLE after responding to AP_CREATE, even if the guest-specified VMSA is unusable, e.g. isn't backed by a memslot or doesn't have a backing guest_memfd page. If the VMSA is unusable, leaving the vCPU in a non-running state will effectively hang the vCPU instead of reporting an error to userspace. This will also allow retrying the VMSA load in the future, to fix a bug where KVM doesn't honor guest_memfd invalidation events, e.g. if AP_CREATION races with PUNCH_HOLE. Cc: stable@vger.kernel.org # 6.12.x Reviewed-by: Michael Roth Link: https://patch.msgid.link/20260709204948.1988414-4-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Extract loading of guest-provided VMSA to a separate helper

2026-09-02T12:33:18+00:00

commit 0060569e4f18a7dee2dd8728595e909f19a23c24 upstream. Extract the loading/retrieval of a guest-provided VMSA to a separate helper so that KVM can reuse the core logic when refreshing the VMSA after an MMU invalidation from guest_memfd. No functional change intended. Cc: stable@vger.kernel.org # 6.12.x Reviewed-by: Michael Roth Link: https://patch.msgid.link/20260709204948.1988414-3-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Track the GPA of the guest-controlled VMSA used for SNP guests

2026-09-02T12:33:18+00:00

commit 42a39ad5d592aec87a70527a4e694f6210694482 upstream. Track the GPA of the guest-provided VMSA used after AP_CREATION events when running SNP guests, instead of simply tracking whether or not the vCPU is using a guest-provided VMSA. KVM needs to know the GPA of the VMSA that's actively being used so that it can react to MMU invalidation events, i.e. so that KVM can drop the VMSA if its backing guest_memfd page is punched out of existence. Opportunistically rename snp_vmsa_gpa to clarify that it tracks the pending VMSA GPA, whereas snp_guest_vmsa_gpa now tracks the in-use VMSA GPA. Note! Take care to track the GPA, not the GFN, as VALID_PAGE() won't behave correctly if an invalid GFN is converted to a GPA for checking. Note #2! Keep snp_has_guest_vmsa so that switching to a guest-provided VMSA is sticky, even if the guest-provided VMSA becomes invalid. No functional change intended. Cc: stable@vger.kernel.org # 6.12.x Reviewed-by: Michael Roth Link: https://patch.msgid.link/20260709204948.1988414-2-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Drop FOLL_WRITE for encrypted region registration

2026-09-02T12:33:18+00:00

commit ee1a586dd1fa2f245b3b753a3e44d9263a49240b upstream. When pinning SEV guest memory, drop FOLL_WRITE and rely on FOLL_LONGTERM to break CoW, as *KVM* doesn't actually to the memory using the GUP'd pages. Omitting FOLL_WRITE fixes a regression when using file-backed guest memory that was introduced when KVM (correctly) added FOLL_LONG (e.g. to ensure anonymous memory is migrated out of MIGRATE_CMA/ZONE_MOVABLE before a long term pin). Unfortunately, as of commits: 8ac268436e6d ("mm/gup: disallow FOLL_LONGTERM GUP-nonfast writing to file-backed mappings") a6e79df92e4a ("mm/gup: disallow FOLL_LONGTERM GUP-fast writing to file-backed mappings") GUP uses FOLL_LONGTERM as a canary of sorts to detect pins that are likely to be problematic, and disallows WRITE+LONGTERM pins for file-backed memory. As a result, backing SEV+ guests with file-backed memory, e.g. virtio-pmem, fails due to the disallowed FOLL_LONGTERM+FOLL_WRITE combination. Note, in the past, FOLL_WRITE was required to trigger CoW unsharing, to prevent replacing the page in the (primary MMU's) page tables during a later write fault after already having pinned a (shared) page in MAP_PRIVATE mappings. FOLL_LONGTERM does that nowadays, even without FOLL_WRITE (see gup_must_unshare()). Fixes: 7e066cb9b71a ("KVM: SEV: Use long-term pin when registering encrypted memory regions") Cc: stable@vger.kernel.org Suggested-by: "David Hildenbrand (Arm)" Link: https://lore.kernel.org/all/ad784f05-b36c-4e91-9f17-4c5b826735d0@kernel.org/ Signed-off-by: Pankaj Gupta Acked-by: David Hildenbrand (Arm) Acked-by: Lorenzo Stoakes (ARM) Link: https://patch.msgid.link/20260715063626.65899-1-pankaj.gupta@amd.com [sean: massage changelog, add comment about CoW unsharing] Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: SEV: Allocate full pages for {DE,EN}CRYPT ops on SNP-enabled hosts

2026-09-02T12:33:18+00:00

commit a33c40b93ccf5177e042253807d40e0b92e7f206 upstream. When {de,en}crypting memory of an SEV or SEV-ES guest on an SNP-enabled host via a temporary buffer, allocate a full 4KiB page for the buffer to ensure the page containing the buffer is wholly owned by KVM, i.e. won't be concurrently allocated and accessed by other kernel code while KVM is using the buffer to {de,en}crypt memory. On SNP-enabled platforms, when sending SEV/SEV-ES commands that trigger firmware writes to memory, the to-be-written page(s) must be (temporarily) assigned to Firmware (as required by the SNP architecture, to guard against using such commands as gadgets to attack SNP guests). See snp_map_cmd_buf_desc() and friends. Unfortunately, transferring ownership of a page to Firmware makes the page inaccessible to software, and thus writes generate RMP #PF violations. If KVM uses a sub-page allocation for its temporary buffer, some other actor in the kernel can allocate and use the other portions of the page, and thus trigger unexpected (and seemingly spurious) RMP #PF violations due to software attempting to access a Firmware-owned page. BUG: unable to handle page fault for address: ffff906ae30f0300 #PF: supervisor write access in kernel mode #PF: error_code(0x80000003) - RMP violation PGD 6b1b80d067 P4D 6b1b80d067 PUD 100231e2063 PMD 10055a88063 PTE 80000100630f0163 SEV-SNP: PFN 0x100630f0 unassigned, dumping non-zero entries in 2M PFN region: [0x10063000 - 0x10063200] Oops: Oops: 0003 [#1] SMP CPU: 70 UID: 0 PID: 10658 Comm: svw_WaiterThrea Tainted: G U W O 7.1.0-smp--c22293789940-seanjc-next #1 PREEMPTLAZY Tainted: [U]=USER, [W]=WARN, [O]=OOT_MODULE Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.86.0-102 01/25/2026 RIP: 0010:memset+0xf/0x20 Call Trace: __kvmalloc_node_noprof+0x2a4/0x710 do_getxattr+0x4e/0x130 path_getxattrat+0x125/0x1b0 do_syscall_64+0x10a/0x480 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f3a22cb6daa Modules linked in: kvm_amd kvm irqbypass vfat fat ccp k10temp sha3 libsha3 i2c_piix4 gq(O) cdc_acm xhci_pci xhci_hcd gsmi: Log Shutdown Reason 0x03 CR2: ffff906ae30f0300 ---[ end trace 0000000000000000 ]--- RIP: 0010:memset+0xf/0x20 Kernel panic - not syncing: Fatal exception Kernel Offset: 0x39e00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) gsmi: Log Shutdown Reason 0x02 Fixes: 4c735bf1bc22 ("KVM: SEV: Allocate only as many bytes as needed for temp crypt buffers") Cc: stable@vger.kernel.org Cc: Michael Roth Debugged-by: Michael Roth Link: https://patch.msgid.link/20260723211306.75397-1-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

Merge tag 'x86_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-08-16T17:28:31+00:00

Pull x86 fix from Borislav Petkov: - Add a proper kernel cmdline option to control the TLB invalidation method on x86 prompted mainly by a recent finding on AMD related to INVLPGB/TYLBSYNC invalidations. Having the command line option is simply another way to alleviate the situation short-term * tag 'x86_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU: Add a tlbi= cmdline switch

Merge tag 'soc-fixes-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

2026-08-15T15:36:26+00:00

Pull SoC fixes from Arnd Bergmann: "These are three last-minute fixes for the 7.2 release, though nothing alarming: - one error handling fix for optee firmware - incorrect i2c data for the apple M3 that was added in 7.2 - a boot time warning fix for nvidia tegra" * tag 'soc-fixes-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: arm64: tegra: Add EL2 virtual timer interrupt for Tegra194 arm64: dts: apple: t8122: Fix I2C resources optee: ffa: Add NULL check in optee_ffa_lend_protmem

Merge tag 'for-linus' of https://github.com/openrisc/linux

2026-08-15T15:05:58+00:00

Pull OpenRISC fix from Stafford Horne: "A bug fix found by researchers: - mask all privileged bits when restoring the supervisor register from sigreturn" * tag 'for-linus' of https://github.com/openrisc/linux: openrisc: signal: do not restore privileged SR bits on sigreturn