linux-dev/arch/powerpc/kvm, branch master

KVM: PPC: BookS PR-KVM and BookE do not support context tracking

2022-10-18T11:46:19Z

The context tracking code in PR-KVM and BookE implementations is not complete, and can cause host crashes if context tracking is enabled. Make these implementations depend on !CONTEXT_TRACKING_USER. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221014030729.2077151-2-npiggin@gmail.com

Merge tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-14T19:28:43Z

Pull more MM updates from Andrew Morton: - fix a race which causes page refcounting errors in ZONE_DEVICE pages (Alistair Popple) - fix userfaultfd test harness instability (Peter Xu) - various other patches in MM, mainly fixes * tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits) highmem: fix kmap_to_page() for kmap_local_page() addresses mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page mm/selftest: uffd: explain the write missing fault check mm/hugetlb: use hugetlb_pte_stable in migration race check mm/hugetlb: fix race condition of uffd missing/minor handling zram: always expose rw_page LoongArch: update local TLB if PTE entry exists mm: use update_mmu_tlb() on the second thread kasan: fix array-bounds warnings in tests hmm-tests: add test for migrate_device_range() nouveau/dmem: evict device private memory during release nouveau/dmem: refactor nouveau_dmem_fault_copy_one() mm/migrate_device.c: add migrate_device_range() mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page() mm/memremap.c: take a pgmap reference on page allocation mm: free device private pages have zero refcount mm/memory.c: fix race when faulting a device private page mm/damon: use damon_sz_region() in appropriate place mm/damon: move sz_damon_region to damon_sz_region lib/test_meminit: add checks for the allocation functions ...

mm: free device private pages have zero refcount

2022-10-13T01:51:49Z

Since 27674ef6c73f ("mm: remove the extra ZONE_DEVICE struct page refcount") device private pages have no longer had an extra reference count when the page is in use. However before handing them back to the owning device driver we add an extra reference count such that free pages have a reference count of one. This makes it difficult to tell if a page is free or not because both free and in use pages will have a non-zero refcount. Instead we should return pages to the drivers page allocator with a zero reference count. Kernel code can then safely use kernel functions such as get_page_unless_zero(). Link: https://lkml.kernel.org/r/cf70cf6f8c0bdb8aaebdbfb0d790aea4c683c3c6.1664366292.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple Acked-by: Felix Kuehling Cc: Jason Gunthorpe Cc: Michael Ellerman Cc: Alex Deucher Cc: Christian König Cc: Ben Skeggs Cc: Lyude Paul Cc: Ralph Campbell Cc: Alex Sierra Cc: John Hubbard Cc: Dan Williams Cc: David Hildenbrand Cc: "Huang, Ying" Cc: Matthew Wilcox Cc: Yang Shi Cc: Zi Yan Signed-off-by: Andrew Morton

mm/memory.c: fix race when faulting a device private page

2022-10-13T01:51:49Z

Patch series "Fix several device private page reference counting issues", v2 This series aims to fix a number of page reference counting issues in drivers dealing with device private ZONE_DEVICE pages. These result in use-after-free type bugs, either from accessing a struct page which no longer exists because it has been removed or accessing fields within the struct page which are no longer valid because the page has been freed. During normal usage it is unlikely these will cause any problems. However without these fixes it is possible to crash the kernel from userspace. These crashes can be triggered either by unloading the kernel module or unbinding the device from the driver prior to a userspace task exiting. In modules such as Nouveau it is also possible to trigger some of these issues by explicitly closing the device file-descriptor prior to the task exiting and then accessing device private memory. This involves some minor changes to both PowerPC and AMD GPU code. Unfortunately I lack hardware to test either of those so any help there would be appreciated. The changes mimic what is done in for both Nouveau and hmm-tests though so I doubt they will cause problems. This patch (of 8): When the CPU tries to access a device private page the migrate_to_ram() callback associated with the pgmap for the page is called. However no reference is taken on the faulting page. Therefore a concurrent migration of the device private page can free the page and possibly the underlying pgmap. This results in a race which can crash the kernel due to the migrate_to_ram() function pointer becoming invalid. It also means drivers can't reliably read the zone_device_data field because the page may have been freed with memunmap_pages(). Close the race by getting a reference on the page while holding the ptl to ensure it has not been freed. Unfortunately the elevated reference count will cause the migration required to handle the fault to fail. To avoid this failure pass the faulting page into the migrate_vma functions so that if an elevated reference count is found it can be checked to see if it's expected or not. [mpe@ellerman.id.au: fix build] Link: https://lkml.kernel.org/r/87fsgbf3gh.fsf@mpe.ellerman.id.au Link: https://lkml.kernel.org/r/cover.60659b549d8509ddecafad4f498ee7f03bb23c69.1664366292.git-series.apopple@nvidia.com Link: https://lkml.kernel.org/r/d3e813178a59e565e8d78d9b9a4e2562f6494f90.1664366292.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple Acked-by: Felix Kuehling Cc: Jason Gunthorpe Cc: John Hubbard Cc: Ralph Campbell Cc: Michael Ellerman Cc: Lyude Paul Cc: Alex Deucher Cc: Alex Sierra Cc: Ben Skeggs Cc: Christian König Cc: Dan Williams Cc: David Hildenbrand Cc: "Huang, Ying" Cc: Matthew Wilcox Cc: Yang Shi Cc: Zi Yan Signed-off-by: Andrew Morton

Merge tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2022-10-09T21:05:15Z

Pull powerpc updates from Michael Ellerman: - Remove our now never-true definitions for pgd_huge() and p4d_leaf(). - Add pte_needs_flush() and huge_pmd_needs_flush() for 64-bit. - Add support for syscall wrappers. - Add support for KFENCE on 64-bit. - Update 64-bit HV KVM to use the new guest state entry/exit accounting API. - Support execute-only memory when using the Radix MMU (P9 or later). - Implement CONFIG_PARAVIRT_TIME_ACCOUNTING for pseries guests. - Updates to our linker script to move more data into read-only sections. - Allow the VDSO to be randomised on 32-bit. - Many other small features and fixes. Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Christophe Leroy, David Hildenbrand, Disha Goel, Fabiano Rosas, Gaosheng Cui, Gustavo A. R. Silva, Haren Myneni, Hari Bathini, Jilin Yuan, Joel Stanley, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He, Li Huafei, Lukas Bulwahn, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Rohan McLure, Russell Currey, Sachin Sant, Segher Boessenkool, Shrikanth Hegde, Tyrel Datwyler, Wolfram Sang, ye xingchen, and Zheng Yongjun. * tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) KVM: PPC: Book3S HV: Fix stack frame regs marker powerpc: Don't add __powerpc_ prefix to syscall entry points powerpc/64s/interrupt: Fix stack frame regs marker powerpc/64: Fix msr_check_and_set/clear MSR[EE] race powerpc/64s/interrupt: Change must-hard-mask interrupt check from BUG to WARN powerpc/pseries: Add firmware details to the hardware description powerpc/powernv: Add opal details to the hardware description powerpc: Add device-tree model to the hardware description powerpc/64: Add logical PVR to the hardware description powerpc: Add PVR & CPU name to hardware description powerpc: Add hardware description string powerpc/configs: Enable PPC_UV in powernv_defconfig powerpc/configs: Update config files for removed/renamed symbols powerpc/mm: Fix UBSAN warning reported on hugetlb powerpc/mm: Always update max/min_low_pfn in mem_topology_setup() powerpc/mm/book3s/hash: Rename flush_tlb_pmd_range powerpc: Drops STABS_DEBUG from linker scripts powerpc/64s: Remove lost/old comment powerpc/64s: Remove old STAB comment powerpc: remove orphan systbl_chk.sh ...

KVM: PPC: Book3S HV: Fix stack frame regs marker

2022-10-07T10:30:25Z

The hard-coded marker is out of date now, fix it using the nice define. Fixes: 17773afdcd15 ("powerpc/64: use 32-bit immediate for STACK_FRAME_REGS_MARKER") Reported-by: Joel Stanley Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221006143345.129077-1-npiggin@gmail.com

KVM: PPC: Book3S HV: Implement scheduling wait interval counters in the VPA

2022-09-30T08:35:38Z

PAPR specifies accumulated virtual processor wait intervals that relate to partition scheduling interval times. Implement these counters in the same way as they are repoted by dtl. Reviewed-by: Fabiano Rosas Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220908132545.4085849-5-npiggin@gmail.com

Merge branch 'topic/ppc-kvm' into next

2022-09-30T08:35:16Z

Merge some KVM commits we are keeping in our topic branch.

powerpc/64: provide a helper macro to load r2 with the kernel TOC

2022-09-28T09:22:12Z

A later change stops the kernel using r2 and loads it with a poison value. Provide a PACATOC loading abstraction which can hide this detail. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220926034057.2360083-5-npiggin@gmail.com

KVM: PPC: Book3S HV P9: Restore stolen time logging in dtl

2022-09-27T15:07:19Z

Stolen time logging in dtl was removed from the P9 path, so guests had no stolen time accounting. Add it back in a simpler way that still avoids locks and per-core accounting code. Fixes: ecb6a7207f92 ("KVM: PPC: Book3S HV P9: Remove most of the vcore logic") Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220908132545.4085849-4-npiggin@gmail.com