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2025-03-29Merge tag 's390-6.15-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Add sorting of mcount locations at build time - Rework uaccess functions with C exception handling to shorten inline assembly size and enable full inlining. This yields near-optimal code for small constant copies with a ~40kb kernel size increase - Add support for a configurable STRICT_MM_TYPECHECKS which allows to generate better code, but also allows to have type checking for debug builds - Optimize get_lowcore() for common callers with alternatives that nearly revert to the pre-relocated lowcore code, while also slightly reducing syscall entry and exit time - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_* style macros that call test_facility(), and for features with additional conditions, add a new ALT_TYPE_FEATURE alternative to provide a static branch via alternative patching. Also, move machine feature detection to the decompressor for early patching and add debugging functionality to easily show which alternatives are patched - Add exception table support to early boot / startup code to get rid of the open coded exception handling - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE to ensure correct inlining and unrolling decisions - Remove 2k page table leftovers now that s390 has been switched to always allocate 4k page tables - Split kfence pool into 4k mappings in arch_kfence_init_pool() and remove the architecture-specific kfence_split_mapping() - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence spurious KASAN warnings from opportunistic ftrace argument tracing - Force __atomic_add_const() variants on s390 to always return void, ensuring compile errors for improper usage - Remove s390's ioremap_wt() and pgprot_writethrough() due to mismatched semantics and lack of known users, relying on asm-generic fallbacks - Signal eventfd in vfio-ap to notify userspace when the guest AP configuration changes, including during mdev removal - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap drivers to avoid fake flex array confusion - Cleanup trap code - Remove references to the outdated linux390@de.ibm.com address - Other various small fixes and improvements all over the code * tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (78 commits) s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies s390/kfence: Split kfence pool into 4k mappings in arch_kfence_init_pool() s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth() s390/boot: Ignore vmlinux.map s390/sysctl: Remove "vm/allocate_pgste" sysctl s390: Remove 2k vs 4k page table leftovers s390/tlb: Use mm_has_pgste() instead of mm_alloc_pgste() s390/lowcore: Use lghi instead llilh to clear register s390/syscall: Merge __do_syscall() and do_syscall() s390/spinlock: Implement SPINLOCK_LOCKVAL with inline assembly s390/smp: Implement raw_smp_processor_id() with inline assembly s390/current: Implement current with inline assembly s390/lowcore: Use inline qualifier for get_lowcore() inline assembly s390: Move s390 sysctls into their own file under arch/s390 s390/syscall: Simplify syscall_get_arguments() s390/vfio-ap: Notify userspace that guest's AP config changed when mdev removed s390: Remove ioremap_wt() and pgprot_writethrough() s390/mm: Add configurable STRICT_MM_TYPECHECKS s390/mm: Convert pgste_val() into function s390/mm: Convert pgprot_val() into function ...
2025-03-26Merge tag 'iommu-updates-v6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux Pull iommu updates from Joerg Roedel: "Core iommufd dependencies from Jason: - Change the iommufd fault handle into an always present hwpt handle in the domain - Give iommufd its own SW_MSI implementation along with some IRQ layer rework - Improvements to the handle attach API Core fixes for probe-issues from Robin Intel VT-d changes: - Checking for SVA support in domain allocation and attach paths - Move PCI ATS and PRI configuration into probe paths - Fix a pentential hang on reboot -f - Miscellaneous cleanups AMD-Vi changes: - Support for up to 2k IRQs per PCI device function - Set of smaller fixes ARM-SMMU changes: - SMMUv2 devicetree binding updates for Qualcomm implementations (QCS8300 GPU and MSM8937) - Clean up SMMUv2 runtime PM implementation to help with wider rework of pm_runtime_put_autosuspend() Rockchip driver changes: - Driver adjustments for recent DT probing changes S390 IOMMU changes: - Support for IOMMU passthrough Apple Dart changes: - Driver adjustments to meet ISP device requirements - Null-ptr deref fix - Disable subpage protection for DART 1" * tag 'iommu-updates-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: (54 commits) iommu/vt-d: Fix possible circular locking dependency iommu/vt-d: Don't clobber posted vCPU IRTE when host IRQ affinity changes iommu/vt-d: Put IRTE back into posted MSI mode if vCPU posting is disabled iommu: apple-dart: fix potential null pointer deref iommu/rockchip: Retire global dma_dev workaround iommu/rockchip: Register in a sensible order iommu/rockchip: Allocate per-device data sensibly iommu/mediatek-v1: Support COMPILE_TEST iommu/amd: Enable support for up to 2K interrupts per function iommu/amd: Rename DTE_INTTABLEN* and MAX_IRQS_PER_TABLE macro iommu/amd: Replace slab cache allocator with page allocator iommu/amd: Introduce generic function to set multibit feature value iommu: Don't warn prematurely about dodgy probes iommu/arm-smmu: Set rpm auto_suspend once during probe dt-bindings: arm-smmu: Document QCS8300 GPU SMMU iommu: Get DT/ACPI parsing into the proper probe path iommu: Keep dev->iommu state consistent iommu: Resolve ops in iommu_init_device() iommu: Handle race with default domain setup iommu: Unexport iommu_fwspec_free() ...
2025-03-25Merge tag 'timers-cleanups-2025-03-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer cleanups from Thomas Gleixner: "A treewide hrtimer timer cleanup hrtimers are initialized with hrtimer_init() and a subsequent store to the callback pointer. This turned out to be suboptimal for the upcoming Rust integration and is obviously a silly implementation to begin with. This cleanup replaces the hrtimer_init(T); T->function = cb; sequence with hrtimer_setup(T, cb); The conversion was done with Coccinelle and a few manual fixups. Once the conversion has completely landed in mainline, hrtimer_init() will be removed and the hrtimer::function becomes a private member" * tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits) wifi: rt2x00: Switch to use hrtimer_update_function() io_uring: Use helper function hrtimer_update_function() serial: xilinx_uartps: Use helper function hrtimer_update_function() ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup() RDMA: Switch to use hrtimer_setup() virtio: mem: Switch to use hrtimer_setup() drm/vmwgfx: Switch to use hrtimer_setup() drm/xe/oa: Switch to use hrtimer_setup() drm/vkms: Switch to use hrtimer_setup() drm/msm: Switch to use hrtimer_setup() drm/i915/request: Switch to use hrtimer_setup() drm/i915/uncore: Switch to use hrtimer_setup() drm/i915/pmu: Switch to use hrtimer_setup() drm/i915/perf: Switch to use hrtimer_setup() drm/i915/gvt: Switch to use hrtimer_setup() drm/i915/huc: Switch to use hrtimer_setup() drm/amdgpu: Switch to use hrtimer_setup() stm class: heartbeat: Switch to use hrtimer_setup() i2c: Switch to use hrtimer_setup() iio: Switch to use hrtimer_setup() ...
2025-03-14KVM: s390: pv: fix race when making a page secureClaudio Imbrenda
Holding the pte lock for the page that is being converted to secure is needed to avoid races. A previous commit removed the locking, which caused issues. Fix by locking the pte again. Fixes: 5cbe24350b7d ("KVM: s390: move pv gmap functions into kvm") Reported-by: David Hildenbrand <david@redhat.com> Tested-by: David Hildenbrand <david@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> [david@redhat.com: replace use of get_locked_pte() with folio_walk_start()] Link: https://lore.kernel.org/r/20250312184912.269414-2-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250312184912.269414-2-imbrenda@linux.ibm.com>
2025-03-04s390/asm-offsets: Rename __LC_PGM_INT_CODEHeiko Carstens
Avoid confusion and rename __LC_PGM_INT_CODE since it correlates to the pgm_code member of struct lowcore, and not the pgm_int_code member. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/kvm: Convert MACHINE_HAS_ESOP to machine_has_esop()Heiko Carstens
Use static branch(es) to implement and use machine_has_esop() instead of a runtime check via MACHINE_HAS_ESOP. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/tlb: Convert MACHINE_HAS_TLB_GUEST to machine_has_tlb_guest()Heiko Carstens
Use static branch(es) to implement and use machine_has_tlb_guest() instead of a runtime check via MACHINE_HAS_TLB_GUEST. Also add sclp_early_detect_machine_features() in order to allow for feature detection from the decompressor. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_GS to cpu_has_gs()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-21iommu/s390: handle IOAT registration based on domainMatthew Rosato
At this point, the dma_table is really a property of the s390-iommu domain. Rather than checking its contents elsewhere in the codebase, move the code that registers the table with firmware into s390-iommu and make a decision what to register with firmware based upon the type of domain in use for the device in question. Tested-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Link: https://lore.kernel.org/r/20250212213418.182902-4-mjrosato@linux.ibm.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-02-18KVM: s390: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/all/637865c62963fb8cddf6c4368ca12434988a8c27.1738746821.git.namcao@linutronix.de
2025-01-31KVM: s390: remove the last user of page->indexClaudio Imbrenda
Shadow page tables use page->index to keep the g2 address of the guest page table being shadowed. Instead of keeping the information in page->index, split the address and smear it over the 16-bit softbits areas of 4 PGSTEs. This removes the last s390 user of page->index. Reviewed-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-16-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-16-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: move gmap_shadow_pgt_lookup() into kvmClaudio Imbrenda
Move gmap_shadow_pgt_lookup() from mm/gmap.c into kvm/gaccess.c . Reviewed-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-13-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-13-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: move some gmap shadowing functions away from mm/gmap.cClaudio Imbrenda
Move some gmap shadowing functions from mm/gmap.c to kvm/kvm-s390.c and the newly created kvm/gmap-vsie.c This is a step toward removing gmap from mm. Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-10-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-10-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: get rid of gmap_translate()Claudio Imbrenda
Add gpa_to_hva(), which uses memslots, and use it to replace all uses of gmap_translate(). Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-9-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-9-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: get rid of gmap_fault()Claudio Imbrenda
All gmap page faults are already handled in kvm by the function kvm_s390_handle_dat_fault(); only few users of gmap_fault remained, all within kvm. Convert those calls to use kvm_s390_handle_dat_fault() instead. Remove gmap_fault() entirely since it has no more users. Acked-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-8-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-8-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: use __kvm_faultin_pfn()Claudio Imbrenda
Refactor the existing page fault handling code to use __kvm_faultin_pfn(). This possible now that memslots are always present. Acked-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-7-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-7-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: move pv gmap functions into kvmClaudio Imbrenda
Move gmap related functions from kernel/uv into kvm. Create a new file to collect gmap-related functions. Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> [fixed unpack_one(), thanks mhartmay@linux.ibm.com] Link: https://lore.kernel.org/r/20250123144627.312456-6-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-6-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: fake memslot for ucontrol VMsClaudio Imbrenda
Create a fake memslot for ucontrol VMs. The fake memslot identity-maps userspace. Now memslots will always be present, and ucontrol is not a special case anymore. Suggested-by: Sean Christopherson <seanjc@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20250123144627.312456-4-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-4-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: wrapper for KVM_BUGClaudio Imbrenda
Wrap the call to KVM_BUG; this reduces code duplication and improves readability. Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20250123144627.312456-3-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20250123144627.312456-3-imbrenda@linux.ibm.com>
2025-01-31KVM: s390: vsie: stop using "struct page" for vsie pageDavid Hildenbrand
Now that we no longer use page->index and the page refcount explicitly, let's avoid messing with "struct page" completely. Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Tested-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Message-ID: <20250107154344.1003072-5-david@redhat.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-31KVM: s390: vsie: stop messing with page refcountDavid Hildenbrand
Let's stop messing with the page refcount, and use a flag that is set / cleared atomically to remember whether a vsie page is currently in use. Note that we could use a page flag, or a lower bit of the scb_gpa. Let's keep it simple for now, we have sufficient space. While at it, stop passing "struct kvm *" to put_vsie_page(), it's unused. Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Tested-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Message-ID: <20250107154344.1003072-4-david@redhat.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-31KVM: s390: vsie: stop using page->indexDavid Hildenbrand
Let's stop using page->index, and instead use a field inside "struct vsie_page" to hold that value. We have plenty of space left in there. This is one part of stopping using "struct page" when working with vsie pages. We place the "page_to_virt(page)" strategically, so the next cleanups requires less churn. Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Tested-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Message-ID: <20250107154344.1003072-3-david@redhat.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-31KVM: s390: vsie: fix some corner-cases when grabbing vsie pagesDavid Hildenbrand
We try to reuse the same vsie page when re-executing the vsie with a given SCB address. The result is that we use the same shadow SCB -- residing in the vsie page -- and can avoid flushing the TLB when re-running the vsie on a CPU. So, when we allocate a fresh vsie page, or when we reuse a vsie page for a different SCB address -- reusing the shadow SCB in different context -- we set ihcpu=0xffff to trigger the flush. However, after we looked up the SCB address in the radix tree, but before we grabbed the vsie page by raising the refcount to 2, someone could reuse the vsie page for a different SCB address, adjusting page->index and the radix tree. In that case, we would be reusing the vsie page with a wrong page->index. Another corner case is that we might set the SCB address for a vsie page, but fail the insertion into the radix tree. Whoever would reuse that page would remove the corresponding radix tree entry -- which might now be a valid entry pointing at another page, resulting in the wrong vsie page getting removed from the radix tree. Let's handle such races better, by validating that the SCB address of a vsie page didn't change after we grabbed it (not reuse for a different SCB; the alternative would be performing another tree lookup), and by setting the SCB address to invalid until the insertion in the tree succeeded (SCB addresses are aligned to 512, so ULONG_MAX is invalid). These scenarios are rare, the effects a bit unclear, and these issues were only found by code inspection. Let's CC stable to be safe. Fixes: a3508fbe9dc6 ("KVM: s390: vsie: initial support for nested virtualization") Cc: stable@vger.kernel.org Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Tested-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Message-ID: <20250107154344.1003072-2-david@redhat.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-07KVM: s390: Reject KVM_SET_GSI_ROUTING on ucontrol VMsChristoph Schlameuss
Prevent null pointer dereference when processing KVM_IRQ_ROUTING_S390_ADAPTER routing entries. The ioctl cannot be processed for ucontrol VMs. Fixes: f65470661f36 ("KVM: s390/interrupt: do not pin adapter interrupt pages") Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Tested-by: Hariharan Mari <hari55@linux.ibm.com> Reviewed-by: Hariharan Mari <hari55@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20241216092140.329196-4-schlameuss@linux.ibm.com Message-ID: <20241216092140.329196-4-schlameuss@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-07KVM: s390: Reject setting flic pfault attributes on ucontrol VMsChristoph Schlameuss
Prevent null pointer dereference when processing the KVM_DEV_FLIC_APF_ENABLE and KVM_DEV_FLIC_APF_DISABLE_WAIT ioctls in the interrupt controller. Fixes: 3c038e6be0e2 ("KVM: async_pf: Async page fault support on s390") Reported-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Hariharan Mari <hari55@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20241216092140.329196-2-schlameuss@linux.ibm.com Message-ID: <20241216092140.329196-2-schlameuss@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2025-01-07KVM: s390: vsie: fix virtual/physical address in unpin_scb()Claudio Imbrenda
In commit 77b533411595 ("KVM: s390: VSIE: sort out virtual/physical address in pin_guest_page"), only pin_scb() has been updated. This means that in unpin_scb() a virtual address was still used directly as physical address without conversion. The resulting physical address is obviously wrong and most of the time also invalid. Since commit d0ef8d9fbebe ("KVM: s390: Use kvm_release_page_dirty() to unpin "struct page" memory"), unpin_guest_page() will directly use kvm_release_page_dirty(), instead of kvm_release_pfn_dirty(), which has since been removed. One of the checks that were performed by kvm_release_pfn_dirty() was to verify whether the page was valid at all, and silently return successfully without doing anything if the page was invalid. When kvm_release_pfn_dirty() was still used, the invalid page was thus silently ignored. Now the check is gone and the result is an Oops. This also means that when running with a V!=R kernel, the page was not released, causing a leak. The solution is simply to add the missing virt_to_phys(). Fixes: 77b533411595 ("KVM: s390: VSIE: sort out virtual/physical address in pin_guest_page") Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Nico Boehr <nrb@linux.ibm.com> Link: https://lore.kernel.org/r/20241210083948.23963-1-imbrenda@linux.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20241210083948.23963-1-imbrenda@linux.ibm.com>
2024-11-29Merge tag 's390-6.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Heiko Carstens: - Add swap entry for hugetlbfs support - Add PTE_MARKER support for hugetlbs mappings; this fixes a regression (possible page fault loop) which was introduced when support for UFFDIO_POISON for hugetlbfs was added - Add ARCH_HAS_PREEMPT_LAZY and PREEMPT_DYNAMIC support - Mark IRQ entries in entry code, so that stack tracers can filter out the non-IRQ parts of stack traces. This fixes stack depot capacity limit warnings, since without filtering the number of unique stack traces is huge - In PCI code fix leak of struct zpci_dev object, and fix potential double remove of hotplug slot - Fix pagefault_disable() / pagefault_enable() unbalance in arch_stack_user_walk_common() - A couple of inline assembly optimizations, more cmpxchg() to try_cmpxchg() conversions, and removal of usages of xchg() and cmpxchg() on one and two byte memory areas - Various other small improvements and cleanups * tag 's390-6.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (27 commits) Revert "s390/mm: Allow large pages for KASAN shadow mapping" s390/spinlock: Use flag output constraint for arch_cmpxchg_niai8() s390/spinlock: Use R constraint for arch_load_niai4() s390/spinlock: Generate shorter code for arch_spin_unlock() s390/spinlock: Remove condition code clobber from arch_spin_unlock() s390/spinlock: Use symbolic names in inline assemblies s390: Support PREEMPT_DYNAMIC s390/pci: Fix potential double remove of hotplug slot s390/pci: Fix leak of struct zpci_dev when zpci_add_device() fails s390/mm/hugetlbfs: Add missing includes s390/mm: Add PTE_MARKER support for hugetlbfs mappings s390/mm: Introduce region-third and segment table swap entries s390/mm: Introduce region-third and segment table entry present bits s390/mm: Rearrange region-third and segment table entry SW bits KVM: s390: Increase size of union sca_utility to four bytes KVM: s390: Remove one byte cmpxchg() usage KVM: s390: Use try_cmpxchg() instead of cmpxchg() loops s390/ap: Replace xchg() with WRITE_ONCE() s390/mm: Allow large pages for KASAN shadow mapping s390: Add ARCH_HAS_PREEMPT_LAZY support ...
2024-11-27KVM: s390: Remove one byte cmpxchg() usageHeiko Carstens
Within sca_clear_ext_call() cmpxchg() is used to clear one or two bytes (depending on sca format). The cmpxchg() calls are not supposed to fail; if so that would be a bug. Given that cmpxchg() usage on one and two byte areas generates very inefficient code, replace them with block concurrent WRITE_ONCE() calls, and remove the WARN_ON(). Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20241126102515.3178914-3-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-27KVM: s390: Use try_cmpxchg() instead of cmpxchg() loopsHeiko Carstens
Convert all cmpxchg() loops to try_cmpxchg() loops. With gcc 14 and the usage of flag output operands in try_cmpxchg() this allows the compiler to generate slightly better code. Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20241126102515.3178914-2-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-23Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "The biggest change here is eliminating the awful idea that KVM had of essentially guessing which pfns are refcounted pages. The reason to do so was that KVM needs to map both non-refcounted pages (for example BARs of VFIO devices) and VM_PFNMAP/VM_MIXMEDMAP VMAs that contain refcounted pages. However, the result was security issues in the past, and more recently the inability to map VM_IO and VM_PFNMAP memory that _is_ backed by struct page but is not refcounted. In particular this broke virtio-gpu blob resources (which directly map host graphics buffers into the guest as "vram" for the virtio-gpu device) with the amdgpu driver, because amdgpu allocates non-compound higher order pages and the tail pages could not be mapped into KVM. This requires adjusting all uses of struct page in the per-architecture code, to always work on the pfn whenever possible. The large series that did this, from David Stevens and Sean Christopherson, also cleaned up substantially the set of functions that provided arch code with the pfn for a host virtual addresses. The previous maze of twisty little passages, all different, is replaced by five functions (__gfn_to_page, __kvm_faultin_pfn, the non-__ versions of these two, and kvm_prefetch_pages) saving almost 200 lines of code. ARM: - Support for stage-1 permission indirection (FEAT_S1PIE) and permission overlays (FEAT_S1POE), including nested virt + the emulated page table walker - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call was introduced in PSCIv1.3 as a mechanism to request hibernation, similar to the S4 state in ACPI - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As part of it, introduce trivial initialization of the host's MPAM context so KVM can use the corresponding traps - PMU support under nested virtualization, honoring the guest hypervisor's trap configuration and event filtering when running a nested guest - Fixes to vgic ITS serialization where stale device/interrupt table entries are not zeroed when the mapping is invalidated by the VM - Avoid emulated MMIO completion if userspace has requested synchronous external abort injection - Various fixes and cleanups affecting pKVM, vCPU initialization, and selftests LoongArch: - Add iocsr and mmio bus simulation in kernel. - Add in-kernel interrupt controller emulation. - Add support for virtualization extensions to the eiointc irqchip. PPC: - Drop lingering and utterly obsolete references to PPC970 KVM, which was removed 10 years ago. - Fix incorrect documentation references to non-existing ioctls RISC-V: - Accelerate KVM RISC-V when running as a guest - Perf support to collect KVM guest statistics from host side s390: - New selftests: more ucontrol selftests and CPU model sanity checks - Support for the gen17 CPU model - List registers supported by KVM_GET/SET_ONE_REG in the documentation x86: - Cleanup KVM's handling of Accessed and Dirty bits to dedup code, improve documentation, harden against unexpected changes. Even if the hardware A/D tracking is disabled, it is possible to use the hardware-defined A/D bits to track if a PFN is Accessed and/or Dirty, and that removes a lot of special cases. - Elide TLB flushes when aging secondary PTEs, as has been done in x86's primary MMU for over 10 years. - Recover huge pages in-place in the TDP MMU when dirty page logging is toggled off, instead of zapping them and waiting until the page is re-accessed to create a huge mapping. This reduces vCPU jitter. - Batch TLB flushes when dirty page logging is toggled off. This reduces the time it takes to disable dirty logging by ~3x. - Remove the shrinker that was (poorly) attempting to reclaim shadow page tables in low-memory situations. - Clean up and optimize KVM's handling of writes to MSR_IA32_APICBASE. - Advertise CPUIDs for new instructions in Clearwater Forest - Quirk KVM's misguided behavior of initialized certain feature MSRs to their maximum supported feature set, which can result in KVM creating invalid vCPU state. E.g. initializing PERF_CAPABILITIES to a non-zero value results in the vCPU having invalid state if userspace hides PDCM from the guest, which in turn can lead to save/restore failures. - Fix KVM's handling of non-canonical checks for vCPUs that support LA57 to better follow the "architecture", in quotes because the actual behavior is poorly documented. E.g. most MSR writes and descriptor table loads ignore CR4.LA57 and operate purely on whether the CPU supports LA57. - Bypass the register cache when querying CPL from kvm_sched_out(), as filling the cache from IRQ context is generally unsafe; harden the cache accessors to try to prevent similar issues from occuring in the future. The issue that triggered this change was already fixed in 6.12, but was still kinda latent. - Advertise AMD_IBPB_RET to userspace, and fix a related bug where KVM over-advertises SPEC_CTRL when trying to support cross-vendor VMs. - Minor cleanups - Switch hugepage recovery thread to use vhost_task. These kthreads can consume significant amounts of CPU time on behalf of a VM or in response to how the VM behaves (for example how it accesses its memory); therefore KVM tried to place the thread in the VM's cgroups and charge the CPU time consumed by that work to the VM's container. However the kthreads did not process SIGSTOP/SIGCONT, and therefore cgroups which had KVM instances inside could not complete freezing. Fix this by replacing the kthread with a PF_USER_WORKER thread, via the vhost_task abstraction. Another 100+ lines removed, with generally better behavior too like having these threads properly parented in the process tree. - Revert a workaround for an old CPU erratum (Nehalem/Westmere) that didn't really work; there was really nothing to work around anyway: the broken patch was meant to fix nested virtualization, but the PERF_GLOBAL_CTRL MSR is virtualized and therefore unaffected by the erratum. - Fix 6.12 regression where CONFIG_KVM will be built as a module even if asked to be builtin, as long as neither KVM_INTEL nor KVM_AMD is 'y'. x86 selftests: - x86 selftests can now use AVX. Documentation: - Use rST internal links - Reorganize the introduction to the API document Generic: - Protect vcpu->pid accesses outside of vcpu->mutex with a rwlock instead of RCU, so that running a vCPU on a different task doesn't encounter long due to having to wait for all CPUs become quiescent. In general both reads and writes are rare, but userspace that supports confidential computing is introducing the use of "helper" vCPUs that may jump from one host processor to another. Those will be very happy to trigger a synchronize_rcu(), and the effect on performance is quite the disaster" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (298 commits) KVM: x86: Break CONFIG_KVM_X86's direct dependency on KVM_INTEL || KVM_AMD KVM: x86: add back X86_LOCAL_APIC dependency Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()" KVM: x86: switch hugepage recovery thread to vhost_task KVM: x86: expose MSR_PLATFORM_INFO as a feature MSR x86: KVM: Advertise CPUIDs for new instructions in Clearwater Forest Documentation: KVM: fix malformed table irqchip/loongson-eiointc: Add virt extension support LoongArch: KVM: Add irqfd support LoongArch: KVM: Add PCHPIC user mode read and write functions LoongArch: KVM: Add PCHPIC read and write functions LoongArch: KVM: Add PCHPIC device support LoongArch: KVM: Add EIOINTC user mode read and write functions LoongArch: KVM: Add EIOINTC read and write functions LoongArch: KVM: Add EIOINTC device support LoongArch: KVM: Add IPI user mode read and write function LoongArch: KVM: Add IPI read and write function LoongArch: KVM: Add IPI device support LoongArch: KVM: Add iocsr and mmio bus simulation in kernel KVM: arm64: Pass on SVE mapping failures ...
2024-11-18Merge tag 's390-6.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: - Add firmware sysfs interface which allows user space to retrieve the dump area size of the machine - Add 'measurement_chars_full' CHPID sysfs attribute to make the complete associated Channel-Measurements Characteristics Block available - Add virtio-mem support - Move gmap aka KVM page fault handling from the main fault handler to KVM code. This is the first step to make s390 KVM page fault handling similar to other architectures. With this first step the main fault handler does not have any special handling anymore, and therefore convert it to support LOCK_MM_AND_FIND_VMA - With gcc 14 s390 support for flag output operand support for inline assemblies was added. This allows for several optimizations: - Provide a cmpxchg inline assembly which makes use of this, and provide all variants of arch_try_cmpxchg() so that the compiler can generate slightly better code - Convert a few cmpxchg() loops to try_cmpxchg() loops - Similar to x86 add a CC_OUT() helper macro (and other macros), and convert all inline assemblies to make use of them, so that depending on compiler version better code can be generated - List installed host-key hashes in sysfs if the machine supports the Query Ultravisor Keys UVC - Add 'Retrieve Secret' ioctl which allows user space in protected execution guests to retrieve previously stored secrets from the Ultravisor - Add pkey-uv module which supports the conversion of Ultravisor retrievable secrets to protected keys - Extend the existing paes cipher to exploit the full AES-XTS hardware acceleration introduced with message-security assist extension 10 - Convert hopefully all sysfs show functions to use sysfs_emit() so that the constant flow of such patches stop - For PCI devices make use of the newly added Topology ID attribute to enable whole card multi-function support despite the change to PCHID per port. Additionally improve the overall robustness and usability of the multifunction support - Various other small improvements, fixes, and cleanups * tag 's390-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (133 commits) s390/cio/ioasm: Convert to use flag output macros s390/cio/qdio: Convert to use flag output macros s390/sclp: Convert to use flag output macros s390/dasd: Convert to use flag output macros s390/boot/physmem: Convert to use flag output macros s390/pci: Convert to use flag output macros s390/kvm: Convert to use flag output macros s390/extmem: Convert to use flag output macros s390/string: Convert to use flag output macros s390/diag: Convert to use flag output macros s390/irq: Convert to use flag output macros s390/smp: Convert to use flag output macros s390/uv: Convert to use flag output macros s390/pai: Convert to use flag output macros s390/mm: Convert to use flag output macros s390/cpu_mf: Convert to use flag output macros s390/cpcmd: Convert to use flag output macros s390/topology: Convert to use flag output macros s390/time: Convert to use flag output macros s390/pageattr: Convert to use flag output macros ...
2024-11-13s390/kvm: Convert to use flag output macrosHeiko Carstens
Use flag output macros in inline asm to allow for better code generation if the compiler has support for the flag output constraint. Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-11-12Merge tag 'kvm-s390-next-6.13-1' of ↵Paolo Bonzini
https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD - second part of the ucontrol selftest - cpumodel sanity check selftest - gen17 cpumodel changes
2024-11-11KVM: s390: add gen17 facilities to CPU modelHendrik Brueckner
Add gen17 facilities and let KVM_CAP_S390_VECTOR_REGISTERS handle the enablement of the vector extension facilities. Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241107152319.77816-4-brueckner@linux.ibm.com Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Message-ID: <20241107152319.77816-4-brueckner@linux.ibm.com>
2024-11-11KVM: s390: add msa11 to cpu modelHendrik Brueckner
Message-security-assist 11 introduces pckmo subfunctions to encrypt hmac keys. Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241107152319.77816-3-brueckner@linux.ibm.com Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Message-ID: <20241107152319.77816-3-brueckner@linux.ibm.com>
2024-11-11KVM: s390: add concurrent-function facility to cpu modelHendrik Brueckner
Adding support for concurrent-functions facility which provides additional subfunctions. Signed-off-by: Hendrik Brueckner <brueckner@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241107152319.77816-2-brueckner@linux.ibm.com Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Message-ID: <20241107152319.77816-2-brueckner@linux.ibm.com>
2024-11-08Merge tag 'kvm-riscv-6.13-1' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini
KVM/riscv changes for 6.13 - Accelerate KVM RISC-V when running as a guest - Perf support to collect KVM guest statistics from host side
2024-11-07s390/kvm: Mask extra bits from program interrupt codeClaudio Imbrenda
The program interrupt code has some extra bits that are sometimes set by hardware for various reasons; those bits should be ignored when the program interrupt number is needed for interrupt handling. Fixes: 05066cafa925 ("s390/mm/fault: Handle guest-related program interrupts in KVM") Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com> Link: https://lore.kernel.org/r/20241031120316.25462-1-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-31s390/kvm: Initialize uninitialized flags variableClaudio Imbrenda
The flags variable was being used uninitialized. Initialize it to 0 as expected. For some reason neither gcc nor clang reported a warning. Fixes: 05066cafa925 ("s390/mm/fault: Handle guest-related program interrupts in KVM") Reported-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20241030161906.85476-1-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29s390/kvm: Stop using gmap_{en,dis}able()Claudio Imbrenda
Stop using gmap_enable(), gmap_disable(), gmap_get_enabled(). The correct guest ASCE is passed as a parameter of sie64a(), there is no need to save the current gmap in lowcore. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20241022120601.167009-7-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29s390/mm/fault: Handle guest-related program interrupts in KVMClaudio Imbrenda
Any program interrupt that happens in the host during the execution of a KVM guest will now short circuit the fault handler and return to KVM immediately. Guest fault handling (including pfault) will happen entirely inside KVM. When sie64a() returns zero, current->thread.gmap_int_code will contain the program interrupt number that caused the exit, or zero if the exit was not caused by a host program interrupt. KVM will now take care of handling all guest faults in vcpu_post_run(). Since gmap faults will not be visible by the rest of the kernel, remove GMAP_FAULT, the linux fault handlers for secure execution faults, the exception table entries for the sie instruction, the nop padding after the sie instruction, and all other references to guest faults from the s390 code. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Co-developed-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20241022120601.167009-6-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-29s390/kvm: Remove kvm_arch_fault_in_page()Claudio Imbrenda
kvm_arch_fault_in_page() is a useless wrapper around gmap_fault(); just use gmap_fault() directly instead. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20241022120601.167009-3-imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-25KVM: s390: Use kvm_release_page_dirty() to unpin "struct page" memorySean Christopherson
Use kvm_release_page_dirty() when unpinning guest pages, as the pfn was retrieved via pin_guest_page(), i.e. is guaranteed to be backed by struct page memory. This will allow dropping kvm_release_pfn_dirty() and friends. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241010182427.1434605-81-seanjc@google.com>
2024-10-25KVM: Drop KVM_ERR_PTR_BAD_PAGE and instead return NULL to indicate an errorSean Christopherson
Remove KVM_ERR_PTR_BAD_PAGE and instead return NULL, as "bad page" is just a leftover bit of weirdness from days of old when KVM stuffed a "bad" page into the guest instead of actually handling missing pages. See commit cea7bb21280e ("KVM: MMU: Make gfn_to_page() always safe"). Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Tested-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241010182427.1434605-2-seanjc@google.com>
2024-10-25s390: Fix various typosHeiko Carstens
Run codespell on arch/s390 and drivers/s390 and fix all typos. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-10KVM: s390: Change virtual to physical address access in diag 0x258 handlerMichael Mueller
The parameters for the diag 0x258 are real addresses, not virtual, but KVM was using them as virtual addresses. This only happened to work, since the Linux kernel as a guest used to have a 1:1 mapping for physical vs virtual addresses. Fix KVM so that it correctly uses the addresses as real addresses. Cc: stable@vger.kernel.org Fixes: 8ae04b8f500b ("KVM: s390: Guest's memory access functions get access registers") Suggested-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Michael Mueller <mimu@linux.ibm.com> Signed-off-by: Nico Boehr <nrb@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20240917151904.74314-3-nrb@linux.ibm.com Acked-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-10KVM: s390: gaccess: Check if guest address is in memslotNico Boehr
Previously, access_guest_page() did not check whether the given guest address is inside of a memslot. This is not a problem, since kvm_write_guest_page/kvm_read_guest_page return -EFAULT in this case. However, -EFAULT is also returned when copy_to/from_user fails. When emulating a guest instruction, the address being outside a memslot usually means that an addressing exception should be injected into the guest. Failure in copy_to/from_user however indicates that something is wrong in userspace and hence should be handled there. To be able to distinguish these two cases, return PGM_ADDRESSING in access_guest_page() when the guest address is outside guest memory. In access_guest_real(), populate vcpu->arch.pgm.code such that kvm_s390_inject_prog_cond() can be used in the caller for injecting into the guest (if applicable). Since this adds a new return value to access_guest_page(), we need to make sure that other callers are not confused by the new positive return value. There are the following users of access_guest_page(): - access_guest_with_key() does the checking itself (in guest_range_to_gpas()), so this case should never happen. Even if, the handling is set up properly. - access_guest_real() just passes the return code to its callers, which are: - read_guest_real() - see below - write_guest_real() - see below There are the following users of read_guest_real(): - ar_translation() in gaccess.c which already returns PGM_* - setup_apcb10(), setup_apcb00(), setup_apcb11() in vsie.c which always return -EFAULT on read_guest_read() nonzero return - no change - shadow_crycb(), handle_stfle() always present this as validity, this could be handled better but doesn't change current behaviour - no change There are the following users of write_guest_real(): - kvm_s390_store_status_unloaded() always returns -EFAULT on write_guest_real() failure. Fixes: 2293897805c2 ("KVM: s390: add architecture compliant guest access functions") Cc: stable@vger.kernel.org Signed-off-by: Nico Boehr <nrb@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20240917151904.74314-2-nrb@linux.ibm.com Acked-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-08-19KVM: s390: Fix SORTL and DFLTCC instruction format error in __insn32_queryHariharan Mari
The __insn32_query() function incorrectly uses the RRF instruction format for both the SORTL (RRE format) and DFLTCC (RRF format) instructions. To fix this issue, add separate query functions for SORTL and DFLTCC that use the appropriate instruction formats. Additionally pass the query operand as a pointer to the entire array of 32 elements to slightly optimize performance and readability. Fixes: d668139718a9 ("KVM: s390: provide query function for instructions returning 32 byte") Suggested-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Hariharan Mari <hari55@linux.ibm.com> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2024-08-06KVM: s390: fix validity interception issue when gisa is switched offMichael Mueller
We might run into a SIE validity if gisa has been disabled either via using kernel parameter "kvm.use_gisa=0" or by setting the related sysfs attribute to N (echo N >/sys/module/kvm/parameters/use_gisa). The validity is caused by an invalid value in the SIE control block's gisa designation. That happens because we pass the uninitialized gisa origin to virt_to_phys() before writing it to the gisa designation. To fix this we return 0 in kvm_s390_get_gisa_desc() if the origin is 0. kvm_s390_get_gisa_desc() is used to determine which gisa designation to set in the SIE control block. A value of 0 in the gisa designation disables gisa usage. The issue surfaces in the host kernel with the following kernel message as soon a new kvm guest start is attemted. kvm: unhandled validity intercept 0x1011 WARNING: CPU: 0 PID: 781237 at arch/s390/kvm/intercept.c:101 kvm_handle_sie_intercept+0x42e/0x4d0 [kvm] Modules linked in: vhost_net tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT xt_tcpudp nft_compat x_tables nf_nat_tftp nf_conntrack_tftp vfio_pci_core irqbypass vhost_vsock vmw_vsock_virtio_transport_common vsock vhost vhost_iotlb kvm nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables sunrpc mlx5_ib ib_uverbs ib_core mlx5_core uvdevice s390_trng eadm_sch vfio_ccw zcrypt_cex4 mdev vfio_iommu_type1 vfio sch_fq_codel drm i2c_core loop drm_panel_orientation_quirks configfs nfnetlink lcs ctcm fsm dm_service_time ghash_s390 prng chacha_s390 libchacha aes_s390 des_s390 libdes sha3_512_s390 sha3_256_s390 sha512_s390 sha256_s390 sha1_s390 sha_common dm_mirror dm_region_hash dm_log zfcp scsi_transport_fc scsi_dh_rdac scsi_dh_emc scsi_dh_alua pkey zcrypt dm_multipath rng_core autofs4 [last unloaded: vfio_pci] CPU: 0 PID: 781237 Comm: CPU 0/KVM Not tainted 6.10.0-08682-gcad9f11498ea #6 Hardware name: IBM 3931 A01 701 (LPAR) Krnl PSW : 0704c00180000000 000003d93deb0122 (kvm_handle_sie_intercept+0x432/0x4d0 [kvm]) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 Krnl GPRS: 000003d900000027 000003d900000023 0000000000000028 000002cd00000000 000002d063a00900 00000359c6daf708 00000000000bebb5 0000000000001eff 000002cfd82e9000 000002cfd80bc000 0000000000001011 000003d93deda412 000003ff8962df98 000003d93de77ce0 000003d93deb011e 00000359c6daf960 Krnl Code: 000003d93deb0112: c020fffe7259 larl %r2,000003d93de7e5c4 000003d93deb0118: c0e53fa8beac brasl %r14,000003d9bd3c7e70 #000003d93deb011e: af000000 mc 0,0 >000003d93deb0122: a728ffea lhi %r2,-22 000003d93deb0126: a7f4fe24 brc 15,000003d93deafd6e 000003d93deb012a: 9101f0b0 tm 176(%r15),1 000003d93deb012e: a774fe48 brc 7,000003d93deafdbe 000003d93deb0132: 40a0f0ae sth %r10,174(%r15) Call Trace: [<000003d93deb0122>] kvm_handle_sie_intercept+0x432/0x4d0 [kvm] ([<000003d93deb011e>] kvm_handle_sie_intercept+0x42e/0x4d0 [kvm]) [<000003d93deacc10>] vcpu_post_run+0x1d0/0x3b0 [kvm] [<000003d93deaceda>] __vcpu_run+0xea/0x2d0 [kvm] [<000003d93dead9da>] kvm_arch_vcpu_ioctl_run+0x16a/0x430 [kvm] [<000003d93de93ee0>] kvm_vcpu_ioctl+0x190/0x7c0 [kvm] [<000003d9bd728b4e>] vfs_ioctl+0x2e/0x70 [<000003d9bd72a092>] __s390x_sys_ioctl+0xc2/0xd0 [<000003d9be0e9222>] __do_syscall+0x1f2/0x2e0 [<000003d9be0f9a90>] system_call+0x70/0x98 Last Breaking-Event-Address: [<000003d9bd3c7f58>] __warn_printk+0xe8/0xf0 Cc: stable@vger.kernel.org Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com> Fixes: fe0ef0030463 ("KVM: s390: sort out physical vs virtual pointers usage") Signed-off-by: Michael Mueller <mimu@linux.ibm.com> Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20240801123109.2782155-1-mimu@linux.ibm.com Message-ID: <20240801123109.2782155-1-mimu@linux.ibm.com> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2024-07-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - Initial infrastructure for shadow stage-2 MMUs, as part of nested virtualization enablement - Support for userspace changes to the guest CTR_EL0 value, enabling (in part) migration of VMs between heterogenous hardware - Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1 of the protocol - FPSIMD/SVE support for nested, including merged trap configuration and exception routing - New command-line parameter to control the WFx trap behavior under KVM - Introduce kCFI hardening in the EL2 hypervisor - Fixes + cleanups for handling presence/absence of FEAT_TCRX - Miscellaneous fixes + documentation updates LoongArch: - Add paravirt steal time support - Add support for KVM_DIRTY_LOG_INITIALLY_SET - Add perf kvm-stat support for loongarch RISC-V: - Redirect AMO load/store access fault traps to guest - perf kvm stat support - Use guest files for IMSIC virtualization, when available s390: - Assortment of tiny fixes which are not time critical x86: - Fixes for Xen emulation - Add a global struct to consolidate tracking of host values, e.g. EFER - Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the effective APIC bus frequency, because TDX - Print the name of the APICv/AVIC inhibits in the relevant tracepoint - Clean up KVM's handling of vendor specific emulation to consistently act on "compatible with Intel/AMD", versus checking for a specific vendor - Drop MTRR virtualization, and instead always honor guest PAT on CPUs that support self-snoop - Update to the newfangled Intel CPU FMS infrastructure - Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as it reads '0' and writes from userspace are ignored - Misc cleanups x86 - MMU: - Small cleanups, renames and refactoring extracted from the upcoming Intel TDX support - Don't allocate kvm_mmu_page.shadowed_translation for shadow pages that can't hold leafs SPTEs - Unconditionally drop mmu_lock when allocating TDP MMU page tables for eager page splitting, to avoid stalling vCPUs when splitting huge pages - Bug the VM instead of simply warning if KVM tries to split a SPTE that is non-present or not-huge. KVM is guaranteed to end up in a broken state because the callers fully expect a valid SPTE, it's all but dangerous to let more MMU changes happen afterwards x86 - AMD: - Make per-CPU save_area allocations NUMA-aware - Force sev_es_host_save_area() to be inlined to avoid calling into an instrumentable function from noinstr code - Base support for running SEV-SNP guests. API-wise, this includes a new KVM_X86_SNP_VM type, encrypting/measure the initial image into guest memory, and finalizing it before launching it. Internally, there are some gmem/mmu hooks needed to prepare gmem-allocated pages before mapping them into guest private memory ranges This includes basic support for attestation guest requests, enough to say that KVM supports the GHCB 2.0 specification There is no support yet for loading into the firmware those signing keys to be used for attestation requests, and therefore no need yet for the host to provide certificate data for those keys. To support fetching certificate data from userspace, a new KVM exit type will be needed to handle fetching the certificate from userspace. An attempt to define a new KVM_EXIT_COCO / KVM_EXIT_COCO_REQ_CERTS exit type to handle this was introduced in v1 of this patchset, but is still being discussed by community, so for now this patchset only implements a stub version of SNP Extended Guest Requests that does not provide certificate data x86 - Intel: - Remove an unnecessary EPT TLB flush when enabling hardware - Fix a series of bugs that cause KVM to fail to detect nested pending posted interrupts as valid wake eents for a vCPU executing HLT in L2 (with HLT-exiting disable by L1) - KVM: x86: Suppress MMIO that is triggered during task switch emulation Explicitly suppress userspace emulated MMIO exits that are triggered when emulating a task switch as KVM doesn't support userspace MMIO during complex (multi-step) emulation Silently ignoring the exit request can result in the WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to userspace for some other reason prior to purging mmio_needed See commit 0dc902267cb3 ("KVM: x86: Suppress pending MMIO write exits if emulator detects exception") for more details on KVM's limitations with respect to emulated MMIO during complex emulator flows Generic: - Rename the AS_UNMOVABLE flag that was introduced for KVM to AS_INACCESSIBLE, because the special casing needed by these pages is not due to just unmovability (and in fact they are only unmovable because the CPU cannot access them) - New ioctl to populate the KVM page tables in advance, which is useful to mitigate KVM page faults during guest boot or after live migration. The code will also be used by TDX, but (probably) not through the ioctl - Enable halt poll shrinking by default, as Intel found it to be a clear win - Setup empty IRQ routing when creating a VM to avoid having to synchronize SRCU when creating a split IRQCHIP on x86 - Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag that arch code can use for hooking both sched_in() and sched_out() - Take the vCPU @id as an "unsigned long" instead of "u32" to avoid truncating a bogus value from userspace, e.g. to help userspace detect bugs - Mark a vCPU as preempted if and only if it's scheduled out while in the KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest memory when retrieving guest state during live migration blackout Selftests: - Remove dead code in the memslot modification stress test - Treat "branch instructions retired" as supported on all AMD Family 17h+ CPUs - Print the guest pseudo-RNG seed only when it changes, to avoid spamming the log for tests that create lots of VMs - Make the PMU counters test less flaky when counting LLC cache misses by doing CLFLUSH{OPT} in every loop iteration" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits) crypto: ccp: Add the SNP_VLEK_LOAD command KVM: x86/pmu: Add kvm_pmu_call() to simplify static calls of kvm_pmu_ops KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops KVM: x86: Replace static_call_cond() with static_call() KVM: SEV: Provide support for SNP_EXTENDED_GUEST_REQUEST NAE event x86/sev: Move sev_guest.h into common SEV header KVM: SEV: Provide support for SNP_GUEST_REQUEST NAE event KVM: x86: Suppress MMIO that is triggered during task switch emulation KVM: x86/mmu: Clean up make_huge_page_split_spte() definition and intro KVM: x86/mmu: Bug the VM if KVM tries to split a !hugepage SPTE KVM: selftests: x86: Add test for KVM_PRE_FAULT_MEMORY KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory() KVM: x86/mmu: Make kvm_mmu_do_page_fault() return mapped level KVM: x86/mmu: Account pf_{fixed,emulate,spurious} in callers of "do page fault" KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler KVM: Add KVM_PRE_FAULT_MEMORY vcpu ioctl to pre-populate guest memory KVM: Document KVM_PRE_FAULT_MEMORY ioctl mm, virt: merge AS_UNMOVABLE and AS_INACCESSIBLE perf kvm: Add kvm-stat for loongarch64 LoongArch: KVM: Add PV steal time support in guest side ...
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