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2025-04-28x86/sgx: Use SHA-256 library API instead of crypto_shash APIEric Biggers3-31/+3
This user of SHA-256 does not support any other algorithm, so the crypto_shash abstraction provides no value. Just use the SHA-256 library API instead, which is much simpler and easier to use. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20250428183838.799333-1-ebiggers%40kernel.org
2025-04-28x86/microcode/AMD: Use sha256() instead of init/update/finalEric Biggers1-4/+1
Just call sha256() instead of doing the init/update/final sequence. No functional changes. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250428183006.782501-1-ebiggers@kernel.org
2025-04-28x86/sev: Remove unnecessary GFP_KERNEL_ACCOUNT for temporary variablesPeng Hao1-2/+2
Some variables allocated in sev_send_update_data are released when the function exits, so there is no need to set GFP_KERNEL_ACCOUNT. Signed-off-by: Peng Hao <flyingpeng@tencent.com> Link: https://lore.kernel.org/r/20250428063013.62311-1-flyingpeng@tencent.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: x86/mmu: Check and free obsolete roots in kvm_mmu_reload()Yan Zhao2-0/+4
Check request KVM_REQ_MMU_FREE_OBSOLETE_ROOTS to free obsolete roots in kvm_mmu_reload() to prevent kvm_mmu_reload() from seeing a stale obsolete root. Since kvm_mmu_reload() can be called outside the vcpu_enter_guest() path (e.g., kvm_arch_vcpu_pre_fault_memory()), it may be invoked after a root has been marked obsolete and before vcpu_enter_guest() is invoked to process KVM_REQ_MMU_FREE_OBSOLETE_ROOTS and set root.hpa to invalid. This causes kvm_mmu_reload() to fail to load a new root, which can lead to kvm_arch_vcpu_pre_fault_memory() being stuck in the while loop in kvm_tdp_map_page() since RET_PF_RETRY is always returned due to is_page_fault_stale(). Keep the existing check of KVM_REQ_MMU_FREE_OBSOLETE_ROOTS in vcpu_enter_guest() since the cost of kvm_check_request() is negligible, especially a check that's guarded by kvm_request_pending(). Export symbol of kvm_mmu_free_obsolete_roots() as kvm_mmu_reload() is inline and may be called outside of kvm.ko. Fixes: 6e01b7601dfe ("KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()") Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250318013333.5817-1-yan.y.zhao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: x86/mmu: Warn if PFN changes on shadow-present SPTE in shadow MMUYan Zhao1-2/+3
Warn if PFN changes on shadow-present SPTE in mmu_set_spte(). KVM should _never_ change the PFN of a shadow-present SPTE. In mmu_set_spte(), there is a WARN_ON_ONCE() on pfn changes on shadow-present SPTE in mmu_spte_update() to detect this condition. However, that WARN_ON_ONCE() is not hittable since mmu_set_spte() invokes drop_spte() earlier before mmu_spte_update(), which clears SPTE to a !shadow-present state. So, before invoking drop_spte(), add a WARN_ON_ONCE() in mmu_set_spte() to warn PFN change of a shadow-present SPTE. For the spurious prefetch fault, only return RET_PF_SPURIOUS directly when PFN is not changed. When PFN changes, fall through to follow the sequence of drop_spte(), warn of PFN change, make_spte(), flush tlb, rmap_add(). Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250318013310.5781-1-yan.y.zhao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: x86/tdp_mmu: WARN if PFN changes for spurious faultsYan Zhao1-1/+3
Add a WARN() to assert that KVM does _not_ change the PFN of a shadow-present SPTE during spurious fault handling. KVM should _never_ change the PFN of a shadow-present SPTE and TDP MMU already BUG()s on this. However, spurious faults just return early before the existing BUG() could be hit. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250318013238.5732-1-yan.y.zhao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: x86/tdp_mmu: Merge prefetch and access checks for spurious faultsYan Zhao1-5/+1
Combine prefetch and is_access_allowed() checks into a unified path to detect spurious faults, since both cases now share identical logic. No functional changes. Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250318013210.5701-1-yan.y.zhao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: x86/mmu: Further check old SPTE is leaf for spurious prefetch faultYan Zhao2-2/+3
Instead of simply treating a prefetch fault as spurious when there's a shadow-present old SPTE, further check if the old SPTE is leaf to determine if a prefetch fault is spurious. It's not reasonable to treat a prefetch fault as spurious when there's a shadow-present non-leaf SPTE without a corresponding shadow-present leaf SPTE. e.g., in the following sequence, a prefetch fault should not be considered spurious: 1. add a memslot with size 4K 2. prefault GPA A in the memslot 3. delete the memslot (zap all disabled) 4. re-add the memslot with size 2M 5. prefault GPA A again. In step 5, the prefetch fault attempts to install a 2M huge entry. Since step 3 zaps the leaf SPTE for GPA A while keeping the non-leaf SPTE, the leaf entry will remain empty after step 5 if the fetch fault is regarded as spurious due to a shadow-present non-leaf SPTE. Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250318013111.5648-1-yan.y.zhao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: VMX: Flush shadow VMCS on emergency rebootChao Gao1-1/+4
Ensure the shadow VMCS cache is evicted during an emergency reboot to prevent potential memory corruption if the cache is evicted after reboot. This issue was identified through code inspection, as __loaded_vmcs_clear() flushes both the normal VMCS and the shadow VMCS. Avoid checking the "launched" state during an emergency reboot, unlike the behavior in __loaded_vmcs_clear(). This is important because reboot NMIs can interfere with operations like copy_shadow_to_vmcs12(), where shadow VMCSes are loaded directly using VMPTRLD. In such cases, if NMIs occur right after the VMCS load, the shadow VMCSes will be active but the "launched" state may not be set. Fixes: 16f5b9034b69 ("KVM: nVMX: Copy processor-specific shadow-vmcs to VMCS12") Cc: stable@vger.kernel.org Signed-off-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20250324140849.2099723-1-chao.gao@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28KVM: SVM: Treat DEBUGCTL[5:2] as reservedSean Christopherson1-11/+0
Stop ignoring DEBUGCTL[5:2] on AMD CPUs and instead treat them as reserved. KVM has never properly virtualized AMD's legacy PBi bits, but did allow the guest (and host userspace) to set the bits. To avoid breaking guests when running on CPUs with BusLockTrap, which redefined bit 2 to BLCKDB and made bits 5:3 reserved, a previous KVM change ignored bits 5:3, e.g. so that legacy guest software wouldn't inadvertently enable BusLockTrap or hit a VMRUN failure due to setting reserved. To allow for virtualizing BusLockTrap and whatever future features may use bits 5:3, treat bits 5:2 as reserved (and hope that doing so doesn't break any existing guests). Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-28x86/bugs: Allow retbleed=stuff only on IntelDavid Kaplan1-0/+4
The retbleed=stuff mitigation is only applicable for Intel CPUs affected by retbleed. If this option is selected for another vendor, print a warning and fall back to the AUTO option. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-10-david.kaplan@amd.com
2025-04-28x86/bugs: Restructure spectre_v1 mitigationDavid Kaplan1-2/+8
Restructure spectre_v1 to use select/apply functions to create consistent vulnerability handling. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-9-david.kaplan@amd.com
2025-04-28x86/crc: drop "glue" from filenamesEric Biggers4-3/+3
The use of the term "glue" in filenames is a Crypto API-ism that rarely shows up elsewhere in lib/ or arch/*/lib/. I think adopting it there was a mistake. The library just uses standard functions, so the amount of code that could be considered "glue" is quite small. And while often the C functions just wrap the assembly functions, there are also cases like crc32c_arch() in arch/x86/lib/crc32-glue.c that blur the line by in-lining the actual implementation into the C function. That's not "glue code", but rather the actual code. Therefore, let's drop "glue" from the filenames and instead use e.g. crc32.c instead of crc32-glue.c. Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250424002038.179114-8-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
2025-04-28lib/crc: make the CPU feature static keys __ro_after_initEric Biggers3-4/+4
All of the CRC library's CPU feature static_keys are initialized by initcalls and never change afterwards, so there's no need for them to be in the regular .data section. Put them in .data..ro_after_init instead. Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390 Link: https://lore.kernel.org/r/20250413154350.10819-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
2025-04-28x86/bugs: Restructure GDS mitigationDavid Kaplan1-14/+29
Restructure GDS mitigation to use select/apply functions to create consistent vulnerability handling. Define new AUTO mitigation for GDS. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-8-david.kaplan@amd.com
2025-04-28x86/bugs: Restructure SRBDS mitigationDavid Kaplan1-4/+16
Restructure SRBDS to use select/apply functions to create consistent vulnerability handling. Define new AUTO mitigation for SRBDS. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-7-david.kaplan@amd.com
2025-04-28x86/bugs: Remove md_clear_*_mitigation()David Kaplan1-65/+0
The functionality in md_clear_update_mitigation() and md_clear_select_mitigation() is now integrated into the select/update functions for the MDS, TAA, MMIO, and RFDS vulnerabilities. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-6-david.kaplan@amd.com
2025-04-28x86/bugs: Restructure RFDS mitigationDavid Kaplan1-5/+36
Restructure RFDS mitigation to use select/update/apply functions to create consistent vulnerability handling. [ bp: Rename the oneline helper to what it checks. ] Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-5-david.kaplan@amd.com
2025-04-28crypto: x86/polyval - Use API partial block handlingHerbert Xu1-52/+20
Use the Crypto API partial block handling. Also remove the unnecessary SIMD fallback path. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-28crypto: lib/poly1305 - remove INTERNAL symbol and selection of CRYPTOEric Biggers1-1/+1
Now that the architecture-optimized Poly1305 kconfig symbols are defined regardless of CRYPTO, there is no need for CRYPTO_LIB_POLY1305 to select CRYPTO. So, remove that. This makes the indirection through the CRYPTO_LIB_POLY1305_INTERNAL symbol unnecessary, so get rid of that and just use CRYPTO_LIB_POLY1305 directly. Finally, make the fallback to the generic implementation use a default value instead of a select; this makes it consistent with how the arch-optimized code gets enabled and also with how CRYPTO_LIB_BLAKE2S_GENERIC gets enabled. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-28crypto: lib/chacha - remove INTERNAL symbol and selection of CRYPTOEric Biggers1-1/+1
Now that the architecture-optimized ChaCha kconfig symbols are defined regardless of CRYPTO, there is no need for CRYPTO_LIB_CHACHA to select CRYPTO. So, remove that. This makes the indirection through the CRYPTO_LIB_CHACHA_INTERNAL symbol unnecessary, so get rid of that and just use CRYPTO_LIB_CHACHA directly. Finally, make the fallback to the generic implementation use a default value instead of a select; this makes it consistent with how the arch-optimized code gets enabled and also with how CRYPTO_LIB_BLAKE2S_GENERIC gets enabled. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-28crypto: x86 - move library functions to arch/x86/lib/crypto/Eric Biggers14-40/+47
Continue disentangling the crypto library functions from the generic crypto infrastructure by moving the x86 BLAKE2s, ChaCha, and Poly1305 library functions into a new directory arch/x86/lib/crypto/ that does not depend on CRYPTO. This mirrors the distinction between crypto/ and lib/crypto/. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-28crypto: x86 - drop redundant dependencies on X86Eric Biggers1-34/+33
arch/x86/crypto/Kconfig is sourced only when CONFIG_X86=y, so there is no need for the symbols defined inside it to depend on X86. In the case of CRYPTO_TWOFISH_586 and CRYPTO_TWOFISH_X86_64, the dependency was actually on '(X86 || UML_X86)', which suggests that these two symbols were intended to be available under user-mode Linux as well. Yet, again these symbols were defined only when CONFIG_X86=y, so that was not the case. Just remove this redundant dependency. Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2025-04-28x86/bugs: Restructure MMIO mitigationDavid Kaplan1-24/+50
Restructure MMIO mitigation to use select/update/apply functions to create consistent vulnerability handling. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-4-david.kaplan@amd.com
2025-04-28x86/bugs: Restructure TAA mitigationDavid Kaplan1-35/+59
Restructure TAA mitigation to use select/update/apply functions to create consistent vulnerability handling. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-3-david.kaplan@amd.com
2025-04-28x86/bugs: Restructure MDS mitigationDavid Kaplan1-2/+59
Restructure MDS mitigation selection to use select/update/apply functions to create consistent vulnerability handling. [ bp: rename and beef up comment over VERW mitigation selected var for maximum clarity. ] Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/20250418161721.1855190-2-david.kaplan@amd.com
2025-04-26Merge tag 'x86-urgent-2025-04-26' of ↵Linus Torvalds7-17/+28
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Ingo Molnar: - Fix 32-bit kernel boot crash if passed physical memory with more than 32 address bits - Fix Xen PV crash - Work around build bug in certain limited build environments - Fix CTEST instruction decoding in insn_decoder_test * tag 'x86-urgent-2025-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/insn: Fix CTEST instruction decoding x86/boot: Work around broken busybox 'truncate' tool x86/mm: Fix _pgd_alloc() for Xen PV mode x86/e820: Discard high memory that can't be addressed by 32-bit systems
2025-04-26Merge tag 'perf-urgent-2025-04-26' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc perf events fixes from Ingo Molnar: - Use POLLERR for events in error state, instead of the ambiguous POLLHUP error value - Fix non-sampling (counting) events on certain x86 platforms * tag 'perf-urgent-2025-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix non-sampling (counting) events on certain x86 platforms perf/core: Change to POLLERR for pinned events with error
2025-04-26platform/x86/amd/pmc: Use FCH_PM_BASE definitionMario Limonciello1-0/+1
The s2idle MMIO quirk uses a scratch register in the FCH. Adjust the code to clarify that. Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Cc: platform-driver-x86@vger.kernel.org Link: https://lore.kernel.org/r/20250422234830.2840784-5-superm1@kernel.org
2025-04-26i2c: piix4, x86/platform: Move the SB800 PIIX4 FCH definitions to ↵Mario Limonciello1-0/+11
<asm/amd/fch.h> SB800_PIIX4_FCH_PM_ADDR is used to indicate the base address for the FCH PM registers. Multiple drivers may need this base address, so move related defines to a common header location and rename them accordingly. Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andi Shyti <andi.shyti@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Jean Delvare <jdelvare@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Sanket Goswami <Sanket.Goswami@amd.com> Cc: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Cc: linux-i2c@vger.kernel.org Link: https://lore.kernel.org/r/20250422234830.2840784-4-superm1@kernel.org
2025-04-26KVM: SVM: avoid frequency indirect callsPeng Hao1-0/+4
When retpoline is enabled, indirect function calls introduce additional performance overhead. Avoid frequent indirect calls to VMGEXIT when SEV is enabled. Signed-off-by: Peng Hao <flyingpeng@tencent.com> Link: https://lore.kernel.org/r/20250306075425.66693-1-flyingpeng@tencent.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SEV: Configure "ALLOWED_SEV_FEATURES" VMCB FieldKim Phillips3-1/+13
AMD EPYC 5th generation processors have introduced a feature that allows the hypervisor to control the SEV_FEATURES that are set for, or by, a guest [1]. ALLOWED_SEV_FEATURES can be used by the hypervisor to enforce that SEV-ES and SEV-SNP guests cannot enable features that the hypervisor does not want to be enabled. Always enable ALLOWED_SEV_FEATURES. A VMRUN will fail if any non-reserved bits are 1 in SEV_FEATURES but are 0 in ALLOWED_SEV_FEATURES. Some SEV_FEATURES - currently PmcVirtualization and SecureAvic (see Appendix B, Table B-4) - require an opt-in via ALLOWED_SEV_FEATURES, i.e. are off-by-default, whereas all other features are effectively on-by-default, but still honor ALLOWED_SEV_FEATURES. [1] Section 15.36.20 "Allowed SEV Features", AMD64 Architecture Programmer's Manual, Pub. 24593 Rev. 3.42 - March 2024: https://bugzilla.kernel.org/attachment.cgi?id=306250 Co-developed-by: Kishon Vijay Abraham I <kvijayab@amd.com> Signed-off-by: Kishon Vijay Abraham I <kvijayab@amd.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250310201603.1217954-3-kim.phillips@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26x86/cpufeatures: Add "Allowed SEV Features" FeatureKishon Vijay Abraham I1-0/+1
Add CPU feature detection for "Allowed SEV Features" to allow the Hypervisor to enforce that SEV-ES and SEV-SNP guest VMs cannot enable features (via SEV_FEATURES) that the Hypervisor does not support or wish to be enabled. Signed-off-by: Kishon Vijay Abraham I <kvijayab@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/20250310201603.1217954-2-kim.phillips@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SVM: Add a mutex to dump_vmcb() to prevent concurrent outputTom Lendacky1-0/+5
If multiple VMRUN instructions fail, resulting in calls to dump_vmcb(), the output can become interleaved and it is impossible to identify which line of output belongs to which VMCB. Add a mutex to dump_vmcb() so that the output is serialized. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/a880678afd9488e1dd6017445802712f7c02cc6d.1742477213.git.thomas.lendacky@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SVM: Include the vCPU ID when dumping a VMCBTom Lendacky1-2/+2
Provide the vCPU ID of the VMCB in dump_vmcb(). Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/ee0af5a6c1a49aebb4a8291071c3f68cacf107b2.1742477213.git.thomas.lendacky@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SVM: Add the type of VM for which the VMCB/VMSA is being dumpedTom Lendacky1-2/+7
Add the type of VM (SVM, SEV, SEV-ES, or SEV-SNP) being dumped to the dump_vmcb() function. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/7a183a8beedf4ee26c42001160e073a884fe466e.1742477213.git.thomas.lendacky@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SVM: Dump guest register state in dump_vmcb()Tom Lendacky1-0/+53
Guest register state can be useful when debugging, include it as part of dump_vmcb(). Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/a4131a10c082a93610cac12b35dca90292e50f50.1742477213.git.thomas.lendacky@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-26KVM: SVM: Decrypt SEV VMSA in dump_vmcb() if debugging is enabledTom Lendacky3-0/+122
An SEV-ES/SEV-SNP VM save area (VMSA) can be decrypted if the guest policy allows debugging. Update the dump_vmcb() routine to output some of the SEV VMSA contents if possible. This can be useful for debug purposes. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Kim Phillips <kim.phillips@amd.com> Link: https://lore.kernel.org/r/ea3b852c295b6f4b200925ed6b6e2c90d9475e71.1742477213.git.thomas.lendacky@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-25Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds5-61/+82
Pull kvm fixes from Paolo Bonzini: "ARM: - Single fix for broken usage of 'multi-MIDR' infrastructure in PI code, adding an open-coded erratum check for everyone's favorite pile of sand: Cavium ThunderX x86: - Bugfixes from a planned posted interrupt rework - Do not use kvm_rip_read() unconditionally to cater for guests with inaccessible register state" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Do not use kvm_rip_read() unconditionally for KVM_PROFILING KVM: x86: Do not use kvm_rip_read() unconditionally in KVM tracepoints KVM: SVM: WARN if an invalid posted interrupt IRTE entry is added iommu/amd: WARN if KVM attempts to set vCPU affinity without posted intrrupts iommu/amd: Return an error if vCPU affinity is set for non-vCPU IRTE KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer KVM: x86: Explicitly treat routing entry type changes as changes KVM: x86: Reset IRTE to host control if *new* route isn't postable KVM: SVM: Allocate IR data using atomic allocation KVM: SVM: Don't update IRTEs if APICv/AVIC is disabled KVM: arm64, x86: make kvm_arch_has_irq_bypass() inline arm64: Rework checks for broken Cavium HW in the PI code
2025-04-25perf/x86: Optimize the is_x86_eventKan Liang1-9/+10
The current is_x86_event has to go through the hybrid_pmus list to find the matched pmu, then check if it's a X86 PMU and a X86 event. It's not necessary. The X86 PMU has a unique type ID on a non-hybrid machine, and a unique capability type. They are good enough to do the check. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250424134718.311934-5-kan.liang@linux.intel.com
2025-04-25perf/x86/intel: Check the X86 leader for ACR groupKan Liang1-1/+1
The auto counter reload group also requires a group flag in the leader. The leader must be a X86 event. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250424134718.311934-4-kan.liang@linux.intel.com
2025-04-25Merge branch 'perf/urgent'Peter Zijlstra14-90/+88
Merge urgent fixes for dependencies. Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2025-04-25perf/x86/intel/ds: Fix counter backwards of non-precise events ↵Kan Liang1-2/+19
counters-snapshotting The counter backwards may be observed in the PMI handler when counters-snapshotting some non-precise events in the freq mode. For the non-precise events, it's possible the counters-snapshotting records a positive value for an overflowed PEBS event. Then the HW auto-reload mechanism reset the counter to 0 immediately. Because the pebs_event_reset is cleared in the freq mode, which doesn't set the PERF_X86_EVENT_AUTO_RELOAD. In the PMI handler, 0 will be read rather than the positive value recorded in the counters-snapshotting record. The counters-snapshotting case has to be specially handled. Since the event value has been updated when processing the counters-snapshotting record, only needs to set the new period for the counter via x86_pmu_set_period(). Fixes: e02e9b0374c3 ("perf/x86/intel: Support PEBS counters snapshotting") Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250424134718.311934-6-kan.liang@linux.intel.com
2025-04-25perf/x86/intel: Check the X86 leader for pebs_counter_event_groupKan Liang1-1/+1
The PEBS counters snapshotting group also requires a group flag in the leader. The leader must be a X86 event. Fixes: e02e9b0374c3 ("perf/x86/intel: Support PEBS counters snapshotting") Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250424134718.311934-3-kan.liang@linux.intel.com
2025-04-25perf/x86/intel: Only check the group flag for X86 leaderKan Liang2-2/+9
A warning in intel_pmu_lbr_counters_reorder() may be triggered by below perf command. perf record -e "{cpu-clock,cycles/call-graph="lbr"/}" -- sleep 1 It's because the group is mistakenly treated as a branch counter group. The hw.flags of the leader are used to determine whether a group is a branch counters group. However, the hw.flags is only available for a hardware event. The field to store the flags is a union type. For a software event, it's a hrtimer. The corresponding bit may be set if the leader is a software event. For a branch counter group and other groups that have a group flag (e.g., topdown, PEBS counters snapshotting, and ACR), the leader must be a X86 event. Check the X86 event before checking the flag. The patch only fixes the issue for the branch counter group. The following patch will fix the other groups. There may be an alternative way to fix the issue by moving the hw.flags out of the union type. It should work for now. But it's still possible that the flags will be used by other types of events later. As long as that type of event is used as a leader, a similar issue will be triggered. So the alternative way is dropped. Fixes: 33744916196b ("perf/x86/intel: Support branch counters logging") Closes: https://lore.kernel.org/lkml/20250412091423.1839809-1-luogengkun@huaweicloud.com/ Reported-by: Luo Gengkun <luogengkun@huaweicloud.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20250424134718.311934-2-kan.liang@linux.intel.com
2025-04-24KVM: VMX: Use LEAVE in vmx_do_interrupt_irqoff()Uros Bizjak1-2/+1
Micro-optimize vmx_do_interrupt_irqoff() by substituting MOV %RBP,%RSP; POP %RBP instruction sequence with equivalent LEAVE instruction. GCC compiler does this by default for a generic tuning and for all modern processors: DEF_TUNE (X86_TUNE_USE_LEAVE, "use_leave", m_386 | m_CORE_ALL | m_K6_GEODE | m_AMD_MULTIPLE | m_ZHAOXIN | m_TREMONT | m_CORE_HYBRID | m_CORE_ATOM | m_GENERIC) The new code also saves a couple of bytes, from: 27: 48 89 ec mov %rbp,%rsp 2a: 5d pop %rbp to: 27: c9 leave No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lore.kernel.org/r/20250414081131.97374-2-ubizjak@gmail.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-24KVM: nVMX: Check MSR load/store list counts during VM-Enter consistency checksSean Christopherson1-11/+20
Explicitly verify the MSR load/store list counts are below the advertised limit as part of the initial consistency checks on the lists, so that code that consumes the count doesn't need to worry about extreme edge cases. Enforcing the limit during the initial checks fixes a flaw on 32-bit KVM where a sufficiently high @count could lead to overflow: arch/x86/kvm/vmx/nested.c:834 nested_vmx_check_msr_switch() warn: potential user controlled sizeof overflow 'addr + count * 16' '0-u64max + 16-68719476720' arch/x86/kvm/vmx/nested.c 827 static int nested_vmx_check_msr_switch(struct kvm_vcpu *vcpu, 828 u32 count, u64 addr) 829 { 830 if (count == 0) 831 return 0; 832 833 if (!kvm_vcpu_is_legal_aligned_gpa(vcpu, addr, 16) || --> 834 !kvm_vcpu_is_legal_gpa(vcpu, (addr + count * sizeof(struct vmx_msr_entry) - 1))) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ While the SDM doesn't explicitly state an illegal count results in VM-Fail, the SDM states that exceeding the limit may result in undefined behavior. I.e. the SDM gives hardware, and thus KVM, carte blanche to do literally anything in response to a count that exceeds the "recommended" limit. If the limit is exceeded, undefined processor behavior may result (including a machine check during the VMX transition). KVM already enforces the limit when processing the MSRs, i.e. already signals a late VM-Exit Consistency Check for VM-Enter, and generates a VMX Abort for VM-Exit. I.e. explicitly checking the limits simply means KVM will signal VM-Fail instead of VM-Exit or VMX Abort. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/all/44961459-2759-4164-b604-f6bd43da8ce9@stanley.mountain Link: https://lore.kernel.org/r/20250315024402.2363098-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-24KVM: SVM: Fix SNP AP destroy race with VMRUNTom Lendacky2-5/+4
An AP destroy request for a target vCPU is typically followed by an RMPADJUST to remove the VMSA attribute from the page currently being used as the VMSA for the target vCPU. This can result in a vCPU that is about to VMRUN to exit with #VMEXIT_INVALID. This usually does not happen as APs are typically sitting in HLT when being destroyed and therefore the vCPU thread is not running at the time. However, if HLT is allowed inside the VM, then the vCPU could be about to VMRUN when the VMSA attribute is removed from the VMSA page, resulting in a #VMEXIT_INVALID when the vCPU actually issues the VMRUN and causing the guest to crash. An RMPADJUST against an in-use (already running) VMSA results in a #NPF for the vCPU issuing the RMPADJUST, so the VMSA attribute cannot be changed until the VMRUN for target vCPU exits. The Qemu command line option '-overcommit cpu-pm=on' is an example of allowing HLT inside the guest. Update the KVM_REQ_UPDATE_PROTECTED_GUEST_STATE event to include the KVM_REQUEST_WAIT flag. The kvm_vcpu_kick() function will not wait for requests to be honored, so create kvm_make_request_and_kick() that will add a new event request and honor the KVM_REQUEST_WAIT flag. This will ensure that the target vCPU sees the AP destroy request before returning to the initiating vCPU should the target vCPU be in guest mode. Fixes: e366f92ea99e ("KVM: SEV: Support SEV-SNP AP Creation NAE event") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/fe2c885bf35643dd224e91294edb6777d5df23a4.1743097196.git.thomas.lendacky@amd.com [sean: add a comment explaining the use of smp_send_reschedule()] Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-24x86/irq: KVM: Add helper for harvesting PIR to deduplicate KVM and posted MSIsSean Christopherson3-61/+69
Now that posted MSI and KVM harvesting of PIR is identical, extract the code (and posted MSI's wonderful comment) to a common helper. No functional change intended. Link: https://lore.kernel.org/r/20250401163447.846608-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-04-24KVM: VMX: Use arch_xchg() when processing PIR to avoid instrumentationSean Christopherson1-1/+1
Use arch_xchg() when moving IRQs from the PIR to the vIRR, purely to avoid instrumentation so that KVM is compatible with the needs of posted MSI. This will allow extracting the core PIR logic to common code and sharing it between KVM and posted MSI handling. Link: https://lore.kernel.org/r/20250401163447.846608-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>