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2021-02-08x86/sgx: Maintain encl->refcount for each encl->mm_list entryJarkko Sakkinen
This has been shown in tests: [ +0.000008] WARNING: CPU: 3 PID: 7620 at kernel/rcu/srcutree.c:374 cleanup_srcu_struct+0xed/0x100 This is essentially a use-after free, although SRCU notices it as an SRCU cleanup in an invalid context. == Background == SGX has a data structure (struct sgx_encl_mm) which keeps per-mm SGX metadata. This is separate from struct sgx_encl because, in theory, an enclave can be mapped from more than one mm. sgx_encl_mm includes a pointer back to the sgx_encl. This means that sgx_encl must have a longer lifetime than all of the sgx_encl_mm's that point to it. That's usually the case: sgx_encl_mm is freed only after the mmu_notifier is unregistered in sgx_release(). However, there's a race. If the process is exiting, sgx_mmu_notifier_release() can be called in parallel with sgx_release() instead of being called *by* it. The mmu_notifier path keeps encl_mm alive past when sgx_encl can be freed. This inverts the lifetime rules and means that sgx_mmu_notifier_release() can access a freed sgx_encl. == Fix == Increase encl->refcount when encl_mm->encl is established. Release this reference when encl_mm is freed. This ensures that encl outlives encl_mm. [ bp: Massage commit message. ] Fixes: 1728ab54b4be ("x86/sgx: Add a page reclaimer") Reported-by: Haitao Huang <haitao.huang@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20210207221401.29933-1-jarkko@kernel.org
2021-02-01x86/split_lock: Enable the split lock feature on another Alder Lake CPUFenghua Yu
Add Alder Lake mobile processor to CPU list to enumerate and enable the split lock feature. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20210201190007.4031869-1-fenghua.yu@intel.com
2021-01-24Merge tag 'x86_urgent_for_v5.11_rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Add a new Intel model number for Alder Lake - Differentiate which aspects of the FPU state get saved/restored when the FPU is used in-kernel and fix a boot crash on K7 due to early MXCSR access before CR4.OSFXSR is even set. - A couple of noinstr annotation fixes - Correct die ID setting on AMD for users of topology information which need the correct die ID - A SEV-ES fix to handle string port IO to/from kernel memory properly * tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Add another Alder Lake CPU to the Intel family x86/mmx: Use KFPU_387 for MMX string operations x86/fpu: Add kernel_fpu_begin_mask() to selectively initialize state x86/topology: Make __max_die_per_package available unconditionally x86: __always_inline __{rd,wr}msr() x86/mce: Remove explicit/superfluous tracing locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEP locking/lockdep: Cure noinstr fail x86/sev: Fix nonistr violation x86/entry: Fix noinstr fail x86/cpu/amd: Set __max_die_per_package on AMD x86/sev-es: Handle string port IO to kernel memory properly
2021-01-14x86/topology: Make __max_die_per_package available unconditionallyBorislav Petkov
Move it outside of CONFIG_SMP in order to avoid ifdeffery at the usage sites. Fixes: 76e2fc63ca40 ("x86/cpu/amd: Set __max_die_per_package on AMD") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210114111814.5346-1-bp@alien8.de
2021-01-12x86/mce: Remove explicit/superfluous tracingPeter Zijlstra
There's some explicit tracing left in exc_machine_check_kernel(), remove it, as it's already implied by irqentry_nmi_enter(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210106144017.719310466@infradead.org
2021-01-12x86/cpu/amd: Set __max_die_per_package on AMDYazen Ghannam
Set the maximum DIE per package variable on AMD using the NodesPerProcessor topology value. This will be used by RAPL, among others, to determine the maximum number of DIEs on the system in order to do per-DIE manipulations. [ bp: Productize into a proper patch. ] Fixes: 028c221ed190 ("x86/CPU/AMD: Save AMD NodeId as cpu_die_id") Reported-by: Johnathan Smithinovic <johnathan.smithinovic@gmx.at> Reported-by: Rafael Kitover <rkitover@gmail.com> Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Johnathan Smithinovic <johnathan.smithinovic@gmx.at> Tested-by: Rafael Kitover <rkitover@gmail.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=210939 Link: https://lkml.kernel.org/r/20210106112106.GE5729@zn.tnic Link: https://lkml.kernel.org/r/20210111101455.1194-1-bp@alien8.de
2021-01-11Merge tag 'hyperv-fixes-signed-20210111' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - fix kexec panic/hang (Dexuan Cui) - fix occasional crashes when flushing TLB (Wei Liu) * tag 'hyperv-fixes-signed-20210111' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: check cpu mask after interrupt has been disabled x86/hyperv: Fix kexec panic/hang issues
2021-01-08x86/resctrl: Don't move a task to the same resource groupFenghua Yu
Shakeel Butt reported in [1] that a user can request a task to be moved to a resource group even if the task is already in the group. It just wastes time to do the move operation which could be costly to send IPI to a different CPU. Add a sanity check to ensure that the move operation only happens when the task is not already in the resource group. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/962ede65d8e95be793cb61102cca37f7bb018e66.1608243147.git.reinette.chatre@intel.com
2021-01-08x86/resctrl: Use an IPI instead of task_work_add() to update PQR_ASSOC MSRFenghua Yu
Currently, when moving a task to a resource group the PQR_ASSOC MSR is updated with the new closid and rmid in an added task callback. If the task is running, the work is run as soon as possible. If the task is not running, the work is executed later in the kernel exit path when the kernel returns to the task again. Updating the PQR_ASSOC MSR as soon as possible on the CPU a moved task is running is the right thing to do. Queueing work for a task that is not running is unnecessary (the PQR_ASSOC MSR is already updated when the task is scheduled in) and causing system resource waste with the way in which it is implemented: Work to update the PQR_ASSOC register is queued every time the user writes a task id to the "tasks" file, even if the task already belongs to the resource group. This could result in multiple pending work items associated with a single task even if they are all identical and even though only a single update with most recent values is needed. Specifically, even if a task is moved between different resource groups while it is sleeping then it is only the last move that is relevant but yet a work item is queued during each move. This unnecessary queueing of work items could result in significant system resource waste, especially on tasks sleeping for a long time. For example, as demonstrated by Shakeel Butt in [1] writing the same task id to the "tasks" file can quickly consume significant memory. The same problem (wasted system resources) occurs when moving a task between different resource groups. As pointed out by Valentin Schneider in [2] there is an additional issue with the way in which the queueing of work is done in that the task_struct update is currently done after the work is queued, resulting in a race with the register update possibly done before the data needed by the update is available. To solve these issues, update the PQR_ASSOC MSR in a synchronous way right after the new closid and rmid are ready during the task movement, only if the task is running. If a moved task is not running nothing is done since the PQR_ASSOC MSR will be updated next time the task is scheduled. This is the same way used to update the register when tasks are moved as part of resource group removal. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ [2] https://lore.kernel.org/lkml/20201123022433.17905-1-valentin.schneider@arm.com [ bp: Massage commit message and drop the two update_task_closid_rmid() variants. ] Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt <shakeelb@google.com> Reported-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/17aa2fb38fc12ce7bb710106b3e7c7b45acb9e94.1608243147.git.reinette.chatre@intel.com
2021-01-06x86/mtrr: Correct the range check before performing MTRR type lookupsYing-Tsun Huang
In mtrr_type_lookup(), if the input memory address region is not in the MTRR, over 4GB, and not over the top of memory, a write-back attribute is returned. These condition checks are for ensuring the input memory address region is actually mapped to the physical memory. However, if the end address is just aligned with the top of memory, the condition check treats the address is over the top of memory, and write-back attribute is not returned. And this hits in a real use case with NVDIMM: the nd_pmem module tries to map NVDIMMs as cacheable memories when NVDIMMs are connected. If a NVDIMM is the last of the DIMMs, the performance of this NVDIMM becomes very low since it is aligned with the top of memory and its memory type is uncached-minus. Move the input end address change to inclusive up into mtrr_type_lookup(), before checking for the top of memory in either mtrr_type_lookup_{variable,fixed}() helpers. [ bp: Massage commit message. ] Fixes: 0cc705f56e40 ("x86/mm/mtrr: Clean up mtrr_type_lookup()") Signed-off-by: Ying-Tsun Huang <ying-tsun.huang@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201215070721.4349-1-ying-tsun.huang@amd.com
2021-01-05x86/hyperv: Fix kexec panic/hang issuesDexuan Cui
Currently the kexec kernel can panic or hang due to 2 causes: 1) hv_cpu_die() is not called upon kexec, so the hypervisor corrupts the old VP Assist Pages when the kexec kernel runs. The same issue is fixed for hibernation in commit 421f090c819d ("x86/hyperv: Suspend/resume the VP assist page for hibernation"). Now fix it for kexec. 2) hyperv_cleanup() is called too early. In the kexec path, the other CPUs are stopped in hv_machine_shutdown() -> native_machine_shutdown(), so between hv_kexec_handler() and native_machine_shutdown(), the other CPUs can still try to access the hypercall page and cause panic. The workaround "hv_hypercall_pg = NULL;" in hyperv_cleanup() is unreliabe. Move hyperv_cleanup() to a better place. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20201222065541.24312-1-decui@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-12-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Much x86 work was pushed out to 5.12, but ARM more than made up for it. ARM: - PSCI relay at EL2 when "protected KVM" is enabled - New exception injection code - Simplification of AArch32 system register handling - Fix PMU accesses when no PMU is enabled - Expose CSV3 on non-Meltdown hosts - Cache hierarchy discovery fixes - PV steal-time cleanups - Allow function pointers at EL2 - Various host EL2 entry cleanups - Simplification of the EL2 vector allocation s390: - memcg accouting for s390 specific parts of kvm and gmap - selftest for diag318 - new kvm_stat for when async_pf falls back to sync x86: - Tracepoints for the new pagetable code from 5.10 - Catch VFIO and KVM irqfd events before userspace - Reporting dirty pages to userspace with a ring buffer - SEV-ES host support - Nested VMX support for wait-for-SIPI activity state - New feature flag (AVX512 FP16) - New system ioctl to report Hyper-V-compatible paravirtualization features Generic: - Selftest improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits) KVM: SVM: fix 32-bit compilation KVM: SVM: Add AP_JUMP_TABLE support in prep for AP booting KVM: SVM: Provide support to launch and run an SEV-ES guest KVM: SVM: Provide an updated VMRUN invocation for SEV-ES guests KVM: SVM: Provide support for SEV-ES vCPU loading KVM: SVM: Provide support for SEV-ES vCPU creation/loading KVM: SVM: Update ASID allocation to support SEV-ES guests KVM: SVM: Set the encryption mask for the SVM host save area KVM: SVM: Add NMI support for an SEV-ES guest KVM: SVM: Guest FPU state save/restore not needed for SEV-ES guest KVM: SVM: Do not report support for SMM for an SEV-ES guest KVM: x86: Update __get_sregs() / __set_sregs() to support SEV-ES KVM: SVM: Add support for CR8 write traps for an SEV-ES guest KVM: SVM: Add support for CR4 write traps for an SEV-ES guest KVM: SVM: Add support for CR0 write traps for an SEV-ES guest KVM: SVM: Add support for EFER write traps for an SEV-ES guest KVM: SVM: Support string IO operations for an SEV-ES guest KVM: SVM: Support MMIO for an SEV-ES guest KVM: SVM: Create trace events for VMGEXIT MSR protocol processing KVM: SVM: Create trace events for VMGEXIT processing ...
2020-12-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: - a few random little subsystems - almost all of the MM patches which are staged ahead of linux-next material. I'll trickle to post-linux-next work in as the dependents get merged up. Subsystems affected by this patch series: kthread, kbuild, ide, ntfs, ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc, uaccess, zram, and cleanups). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits) mm: cleanup kstrto*() usage mm: fix fall-through warnings for Clang mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at mm: shmem: convert shmem_enabled_show to use sysfs_emit_at mm:backing-dev: use sysfs_emit in macro defining functions mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening mm: use sysfs_emit for struct kobject * uses mm: fix kernel-doc markups zram: break the strict dependency from lzo zram: add stat to gather incompressible pages since zram set up zram: support page writeback mm/process_vm_access: remove redundant initialization of iov_r mm/zsmalloc.c: rework the list_add code in insert_zspage() mm/zswap: move to use crypto_acomp API for hardware acceleration mm/zswap: fix passing zero to 'PTR_ERR' warning mm/zswap: make struct kernel_param_ops definitions const userfaultfd/selftests: hint the test runner on required privilege userfaultfd/selftests: fix retval check for userfaultfd_open() userfaultfd/selftests: always dump something in modes userfaultfd: selftests: make __{s,u}64 format specifiers portable ...
2020-12-15mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aioDmitry Safonov
As kernel expect to see only one of such mappings, any further operations on the VMA-copy may be unexpected by the kernel. Maybe it's being on the safe side, but there doesn't seem to be any expected use-case for this, so restrict it now. Link: https://lkml.kernel.org/r/20201013013416.390574-4-dima@arista.com Fixes: commit e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()") Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-14Merge tag 'x86-apic-2020-12-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Thomas Gleixner: "Yet another large set of x86 interrupt management updates: - Simplification and distangling of the MSI related functionality - Let IO/APIC construct the RTE entries from an MSI message instead of having IO/APIC specific code in the interrupt remapping drivers - Make the retrieval of the parent interrupt domain (vector or remap unit) less hardcoded and use the relevant irqdomain callbacks for selection. - Allow the handling of more than 255 CPUs without a virtualized IOMMU when the hypervisor supports it. This has made been possible by the above modifications and also simplifies the existing workaround in the HyperV specific virtual IOMMU. - Cleanup of the historical timer_works() irq flags related inconsistencies" * tag 'x86-apic-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) x86/ioapic: Cleanup the timer_works() irqflags mess iommu/hyper-v: Remove I/O-APIC ID check from hyperv_irq_remapping_select() iommu/amd: Fix IOMMU interrupt generation in X2APIC mode iommu/amd: Don't register interrupt remapping irqdomain when IR is disabled iommu/amd: Fix union of bitfields in intcapxt support x86/ioapic: Correct the PCI/ISA trigger type selection x86/ioapic: Use I/O-APIC ID for finding irqdomain, not index x86/hyperv: Enable 15-bit APIC ID if the hypervisor supports it x86/kvm: Enable 15-bit extension when KVM_FEATURE_MSI_EXT_DEST_ID detected iommu/hyper-v: Disable IRQ pseudo-remapping if 15 bit APIC IDs are available x86/apic: Support 15 bits of APIC ID in MSI where available x86/ioapic: Handle Extended Destination ID field in RTE iommu/vt-d: Simplify intel_irq_remapping_select() x86: Kill all traces of irq_remapping_get_irq_domain() x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain x86/hpet: Use irq_find_matching_fwspec() to find remapping irqdomain iommu/hyper-v: Implement select() method on remapping irqdomain iommu/vt-d: Implement select() method on remapping irqdomain iommu/amd: Implement select() method on remapping irqdomain x86/apic: Add select() method on vector irqdomain ...
2020-12-14Merge tag 'core-rcu-2020-12-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Thomas Gleixner: "RCU, LKMM and KCSAN updates collected by Paul McKenney. RCU: - Avoid cpuinfo-induced IPI pileups and idle-CPU IPIs - Lockdep-RCU updates reducing the need for __maybe_unused - Tasks-RCU updates - Miscellaneous fixes - Documentation updates - Torture-test updates KCSAN: - updates for selftests, avoiding setting watchpoints on NULL pointers - fix to watchpoint encoding LKMM: - updates for documentation along with some updates to example-code litmus tests" * tag 'core-rcu-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) srcu: Take early exit on memory-allocation failure rcu/tree: Defer kvfree_rcu() allocation to a clean context rcu: Do not report strict GPs for outgoing CPUs rcu: Fix a typo in rcu_blocking_is_gp() header comment rcu: Prevent lockdep-RCU splats on lock acquisition/release rcu/tree: nocb: Avoid raising softirq for offloaded ready-to-execute CBs rcu,ftrace: Fix ftrace recursion rcu/tree: Make struct kernel_param_ops definitions const rcu/tree: Add a warning if CPU being onlined did not report QS already rcu: Clarify nocb kthreads naming in RCU_NOCB_CPU config rcu: Fix single-CPU check in rcu_blocking_is_gp() rcu: Implement rcu_segcblist_is_offloaded() config dependent list.h: Update comment to explicitly note circular lists rcu: Panic after fixed number of stalls x86/smpboot: Move rcu_cpu_starting() earlier rcu: Allow rcu_irq_enter_check_tick() from NMI tools/memory-model: Label MP tests' producers and consumers tools/memory-model: Use "buf" and "flag" for message-passing tests tools/memory-model: Add types to litmus tests tools/memory-model: Add a glossary of LKMM terms ...
2020-12-14Merge tag 'core-entry-2020-12-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core entry/exit updates from Thomas Gleixner: "A set of updates for entry/exit handling: - More generalization of entry/exit functionality - The consolidation work to reclaim TIF flags on x86 and also for non-x86 specific TIF flags which are solely relevant for syscall related work and have been moved into their own storage space. The x86 specific part had to be merged in to avoid a major conflict. - The TIF_NOTIFY_SIGNAL work which replaces the inefficient signal delivery mode of task work and results in an impressive performance improvement for io_uring. The non-x86 consolidation of this is going to come seperate via Jens. - The selective syscall redirection facility which provides a clean and efficient way to support the non-Linux syscalls of WINE by catching them at syscall entry and redirecting them to the user space emulation. This can be utilized for other purposes as well and has been designed carefully to avoid overhead for the regular fastpath. This includes the core changes and the x86 support code. - Simplification of the context tracking entry/exit handling for the users of the generic entry code which guarantee the proper ordering and protection. - Preparatory changes to make the generic entry code accomodate S390 specific requirements which are mostly related to their syscall restart mechanism" * tag 'core-entry-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) entry: Add syscall_exit_to_user_mode_work() entry: Add exit_to_user_mode() wrapper entry_Add_enter_from_user_mode_wrapper entry: Rename exit_to_user_mode() entry: Rename enter_from_user_mode() docs: Document Syscall User Dispatch selftests: Add benchmark for syscall user dispatch selftests: Add kselftest for syscall user dispatch entry: Support Syscall User Dispatch on common syscall entry kernel: Implement selective syscall userspace redirection signal: Expose SYS_USER_DISPATCH si_code type x86: vdso: Expose sigreturn address on vdso to the kernel MAINTAINERS: Add entry for common entry code entry: Fix boot for !CONFIG_GENERIC_ENTRY x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Only define schedule_user() on !HAVE_CONTEXT_TRACKING_OFFSTACK archs sched: Detect call to schedule from critical entry code context_tracking: Don't implement exception_enter/exit() on CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Introduce HAVE_CONTEXT_TRACKING_OFFSTACK x86: Reclaim unused x86 TI flags ...
2020-12-14Merge tag 'x86_cache_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cache resource control updates from Borislav Petkov: - add logic to correct MBM total and local values fixing errata SKX99 and BDF102 (Fenghua Yu) - cleanups * tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Clean up unused function parameter in rmdir path x86/resctrl: Constify kernfs_ops x86/resctrl: Correct MBM total and local values Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
2020-12-14Merge tag 'x86_cleanups_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: "Another branch with a nicely negative diffstat, just the way I like 'em: - Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in the end (Gabriel Krisman Bertazi) - All kinds of minor cleanups all over the tree" * tag 'x86_cleanups_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/ia32_signal: Propagate __user annotation properly x86/alternative: Update text_poke_bp() kernel-doc comment x86/PCI: Make a kernel-doc comment a normal one x86/asm: Drop unused RDPID macro x86/boot/compressed/64: Use TEST %reg,%reg instead of CMP $0,%reg x86/head64: Remove duplicate include x86/mm: Declare 'start' variable where it is used x86/head/64: Remove unused GET_CR2_INTO() macro x86/boot: Remove unused finalize_identity_maps() x86/uaccess: Document copy_from_user_nmi() x86/dumpstack: Make show_trace_log_lvl() static x86/mtrr: Fix a kernel-doc markup x86/setup: Remove unused MCA variables x86, libnvdimm/test: Remove COPY_MC_TEST x86: Reclaim TIF_IA32 and TIF_X32 x86/mm: Convert mmu context ia32_compat into a proper flags field x86/elf: Use e_machine to check for x32/ia32 in setup_additional_pages() elf: Expose ELF header on arch_setup_additional_pages() x86/elf: Use e_machine to select start_thread for x32 elf: Expose ELF header in compat_start_thread() ...
2020-12-14Merge tag 'x86_cpu_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: "Only AMD-specific changes this time: - Save the AMD physical die ID into cpuinfo_x86.cpu_die_id and convert all code to use it (Yazen Ghannam) - Remove a dead and unused TSEG region remapping workaround on AMD (Arvind Sankar)" * tag 'x86_cpu_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu/amd: Remove dead code for TSEG region remapping x86/topology: Set cpu_die_id only if DIE_TYPE found EDAC/mce_amd: Use struct cpuinfo_x86.cpu_die_id for AMD NodeId x86/CPU/AMD: Remove amd_get_nb_id() x86/CPU/AMD: Save AMD NodeId as cpu_die_id
2020-12-14Merge tag 'x86_sgx_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SGC support from Borislav Petkov: "Intel Software Guard eXtensions enablement. This has been long in the making, we were one revision number short of 42. :) Intel SGX is new hardware functionality that can be used by applications to populate protected regions of user code and data called enclaves. Once activated, the new hardware protects enclave code and data from outside access and modification. Enclaves provide a place to store secrets and process data with those secrets. SGX has been used, for example, to decrypt video without exposing the decryption keys to nosy debuggers that might be used to subvert DRM. Software has generally been rewritten specifically to run in enclaves, but there are also projects that try to run limited unmodified software in enclaves. Most of the functionality is concentrated into arch/x86/kernel/cpu/sgx/ except the addition of a new mprotect() hook to control enclave page permissions and support for vDSO exceptions fixup which will is used by SGX enclaves. All this work by Sean Christopherson, Jarkko Sakkinen and many others" * tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits) x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages() x86/sgx: Fix a typo in kernel-doc markup x86/sgx: Fix sgx_ioc_enclave_provision() kernel-doc comment x86/sgx: Return -ERESTARTSYS in sgx_ioc_enclave_add_pages() selftests/sgx: Use a statically generated 3072-bit RSA key x86/sgx: Clarify 'laundry_list' locking x86/sgx: Update MAINTAINERS Documentation/x86: Document SGX kernel architecture x86/sgx: Add ptrace() support for the SGX driver x86/sgx: Add a page reclaimer selftests/x86: Add a selftest for SGX x86/vdso: Implement a vDSO for Intel SGX enclave call x86/traps: Attempt to fixup exceptions in vDSO before signaling x86/fault: Add a helper function to sanitize error code x86/vdso: Add support for exception fixup in vDSO functions x86/sgx: Add SGX_IOC_ENCLAVE_PROVISION x86/sgx: Add SGX_IOC_ENCLAVE_INIT x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES x86/sgx: Add SGX_IOC_ENCLAVE_CREATE x86/sgx: Add an SGX misc driver interface ...
2020-12-14Merge tag 'x86_microcode_update_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loader update from Borislav Petkov: "This one wins the award for most boring pull request ever. But that's a good thing - this is how I like 'em and the microcode loader *should* be boring. :-) A single cleanup removing "break" after a return statement (Tom Rix)" * tag 'x86_microcode_update_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/amd: Remove unneeded break
2020-12-14Merge tag 'ras_updates_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Borislav Petkov: - Enable additional logging mode on older Xeons (Tony Luck) - Pass error records logged by firmware through the MCE decoding chain to provide human-readable error descriptions instead of raw values (Smita Koralahalli) - Some #MC handler fixes (Gabriele Paoloni) - The usual small fixes and cleanups all over. * tag 'ras_updates_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Rename kill_it to kill_current_task x86/mce: Remove redundant call to irq_work_queue() x86/mce: Panic for LMCE only if mca_cfg.tolerant < 3 x86/mce: Move the mce_panic() call and 'kill_it' assignments to the right places x86/mce, cper: Pass x86 CPER through the MCA handling chain x86/mce: Use "safe" MSR functions when enabling additional error logging x86/mce: Correct the detection of invalid notifier priorities x86/mce: Assign boolean values to a bool variable x86/mce: Enable additional error logging on certain Intel CPUs x86/mce: Remove unneeded break
2020-12-14KVM: SVM: Add GHCB accessor functions for retrieving fieldsTom Lendacky
Update the GHCB accessor functions to add functions for retrieve GHCB fields by name. Update existing code to use the new accessor functions. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <664172c53a5fb4959914e1a45d88e805649af0ad.1607620209.git.thomas.lendacky@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-14x86/cpu: Add VM page flush MSR availablility as a CPUID featureTom Lendacky
On systems that do not have hardware enforced cache coherency between encrypted and unencrypted mappings of the same physical page, the hypervisor can use the VM page flush MSR (0xc001011e) to flush the cache contents of an SEV guest page. When a small number of pages are being flushed, this can be used in place of issuing a WBINVD across all CPUs. CPUID 0x8000001f_eax[2] is used to determine if the VM page flush MSR is available. Add a CPUID feature to indicate it is supported and define the MSR. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <f1966379e31f9b208db5257509c4a089a87d33d0.1607620209.git.thomas.lendacky@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-11x86: Enumerate AVX512 FP16 CPUID feature flagKyung Min Park
Enumerate AVX512 Half-precision floating point (FP16) CPUID feature flag. Compared with using FP32, using FP16 cut the number of bits required for storage in half, reducing the exponent from 8 bits to 5, and the mantissa from 23 bits to 10. Using FP16 also enables developers to train and run inference on deep learning models fast when all precision or magnitude (FP32) is not needed. A processor supports AVX512 FP16 if CPUID.(EAX=7,ECX=0):EDX[bit 23] is present. The AVX512 FP16 requires AVX512BW feature be implemented since the instructions for manipulating 32bit masks are associated with AVX512BW. The only in-kernel usage of this is kvm passthrough. The CPU feature flag is shown as "avx512_fp16" in /proc/cpuinfo. Signed-off-by: Kyung Min Park <kyung.min.park@intel.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Message-Id: <20201208033441.28207-2-kyung.min.park@intel.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10x86/resctrl: Fix incorrect local bandwidth when mba_sc is enabledXiaochen Shen
The MBA software controller (mba_sc) is a feedback loop which periodically reads MBM counters and tries to restrict the bandwidth below a user-specified value. It tags along the MBM counter overflow handler to do the updates with 1s interval in mbm_update() and update_mba_bw(). The purpose of mbm_update() is to periodically read the MBM counters to make sure that the hardware counter doesn't wrap around more than once between user samplings. mbm_update() calls __mon_event_count() for local bandwidth updating when mba_sc is not enabled, but calls mbm_bw_count() instead when mba_sc is enabled. __mon_event_count() will not be called for local bandwidth updating in MBM counter overflow handler, but it is still called when reading MBM local bandwidth counter file 'mbm_local_bytes', the call path is as below: rdtgroup_mondata_show() mon_event_read() mon_event_count() __mon_event_count() In __mon_event_count(), m->chunks is updated by delta chunks which is calculated from previous MSR value (m->prev_msr) and current MSR value. When mba_sc is enabled, m->chunks is also updated in mbm_update() by mistake by the delta chunks which is calculated from m->prev_bw_msr instead of m->prev_msr. But m->chunks is not used in update_mba_bw() in the mba_sc feedback loop. When reading MBM local bandwidth counter file, m->chunks was changed unexpectedly by mbm_bw_count(). As a result, the incorrect local bandwidth counter which calculated from incorrect m->chunks is shown to the user. Fix this by removing incorrect m->chunks updating in mbm_bw_count() in MBM counter overflow handler, and always calling __mon_event_count() in mbm_update() to make sure that the hardware local bandwidth counter doesn't wrap around. Test steps: # Run workload with aggressive memory bandwidth (e.g., 10 GB/s) git clone https://github.com/intel/intel-cmt-cat && cd intel-cmt-cat && make ./tools/membw/membw -c 0 -b 10000 --read # Enable MBA software controller mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl # Create control group c1 mkdir /sys/fs/resctrl/c1 # Set MB throttle to 6 GB/s echo "MB:0=6000;1=6000" > /sys/fs/resctrl/c1/schemata # Write PID of the workload to tasks file echo `pidof membw` > /sys/fs/resctrl/c1/tasks # Read local bytes counters twice with 1s interval, the calculated # local bandwidth is not as expected (approaching to 6 GB/s): local_1=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes` sleep 1 local_2=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes` echo "local b/w (bytes/s):" `expr $local_2 - $local_1` Before fix: local b/w (bytes/s): 11076796416 After fix: local b/w (bytes/s): 5465014272 Fixes: ba0f26d8529c (x86/intel_rdt/mba_sc: Prepare for feedback loop) Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/1607063279-19437-1-git-send-email-xiaochen.shen@intel.com
2020-12-08x86/cpu/amd: Remove dead code for TSEG region remappingArvind Sankar
Commit 26bfa5f89486 ("x86, amd: Cleanup init_amd") moved the code that remaps the TSEG region using 4k pages from init_amd() to bsp_init_amd(). However, bsp_init_amd() is executed well before the direct mapping is actually created: setup_arch() -> early_cpu_init() -> early_identify_cpu() -> this_cpu->c_bsp_init() -> bsp_init_amd() ... -> init_mem_mapping() So the change effectively disabled the 4k remapping, because pfn_range_is_mapped() is always false at this point. It has been over six years since the commit, and no-one seems to have noticed this, so just remove the code. The original code was also incomplete, since it doesn't check how large the TSEG address range actually is, so it might remap only part of it in any case. Hygon has copied the incorrect version, so the code has never run on it since the cpu support was added two years ago. Remove it from there as well. Committer notes: This workaround is incomplete anyway: 1. The code must check MSRC001_0113.TValid (SMM TSeg Mask MSR) first, to check whether the TSeg address range is enabled. 2. The code must check whether the range is not 2M aligned - if it is, there's nothing to work around. 3. In all the BIOSes tested, the TSeg range is in a e820 reserved area and those are not mapped anymore, after 66520ebc2df3 ("x86, mm: Only direct map addresses that are marked as E820_RAM") which means, there's nothing to be worked around either. So let's rip it out. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201127171324.1846019-1-nivedita@alum.mit.edu
2020-12-03x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages()Jarkko Sakkinen
The sgx_enclave_add_pages.length field is documented as * @length: length of the data (multiple of the page size) Fail with -EINVAL, when the caller gives a zero length buffer of data to be added as pages to an enclave. Right now 'ret' is returned as uninitialized in that case. [ bp: Flesh out commit message. ] Fixes: c6d26d370767 ("x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/linux-sgx/X8ehQssnslm194ld@mwanda/ Link: https://lkml.kernel.org/r/20201203183527.139317-1-jarkko@kernel.org
2020-12-01x86/mce: Rename kill_it to kill_current_taskGabriele Paoloni
Currently, if an MCE happens in user-mode or while the kernel is copying data from user space, 'kill_it' is used to check if execution of the interrupted task can be recovered or not; the flag name however is not very meaningful, hence rename it to match its goal. [ bp: Massage commit message, rename the queue_task_work() arg too. ] Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201127161819.3106432-6-gabriele.paoloni@intel.com
2020-12-01x86/mce: Remove redundant call to irq_work_queue()Gabriele Paoloni
Currently, __mc_scan_banks() in do_machine_check() does the following callchain: __mc_scan_banks()->mce_log()->irq_work_queue(&mce_irq_work). Hence, the call to irq_work_queue() below after __mc_scan_banks() seems redundant. Just remove it. Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20201127161819.3106432-5-gabriele.paoloni@intel.com
2020-12-01x86/mce: Panic for LMCE only if mca_cfg.tolerant < 3Gabriele Paoloni
Right now for LMCE, if no_way_out is set, mce_panic() is called regardless of mca_cfg.tolerant. This is not correct as, if mca_cfg.tolerant = 3, the code should never panic. Add that check. [ bp: use local ptr 'cfg'. ] Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20201127161819.3106432-4-gabriele.paoloni@intel.com
2020-12-01x86/mce: Move the mce_panic() call and 'kill_it' assignments to the right placesGabriele Paoloni
Right now, for local MCEs the machine calls panic(), if needed, right after lmce is set. For MCE broadcasting, mce_reign() takes care of calling mce_panic(). Hence: - improve readability by moving the conditional evaluation of tolerant up to when kill_it is set first; - move the mce_panic() call up into the statement where mce_end() fails. [ bp: Massage, remove comment in the mce_end() failure case because it is superfluous; use local ptr 'cfg' in both tests. ] Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20201127161819.3106432-3-gabriele.paoloni@intel.com
2020-12-01Merge tag 'v5.10-rc6' into ras/coreBorislav Petkov
Merge the -rc6 tag to pick up dependent changes. Signed-off-by: Borislav Petkov <bp@suse.de>
2020-12-01x86/resctrl: Clean up unused function parameter in rmdir pathXiaochen Shen
Commit fd8d9db3559a ("x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leak") removed superfluous kernfs_get() calls in rdtgroup_ctrl_remove() and rdtgroup_rmdir_ctrl(). That change resulted in an unused function parameter to these two functions. Clean up the unused function parameter in rdtgroup_ctrl_remove(), rdtgroup_rmdir_mon() and their callers rdtgroup_rmdir_ctrl() and rdtgroup_rmdir(). Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/1606759618-13181-1-git-send-email-xiaochen.shen@intel.com
2020-12-01Merge tag 'v5.10-rc6' into x86/cacheBorislav Petkov
Merge -rc6 tag to pick up dependent changes. Signed-off-by: Borislav Petkov <bp@suse.de>
2020-12-01x86/resctrl: Fix AMD L3 QOS CDP enable/disableBabu Moger
When the AMD QoS feature CDP (code and data prioritization) is enabled or disabled, the CDP bit in MSR 0000_0C81 is written on one of the CPUs in an L3 domain (core complex). That is not correct - the CDP bit needs to be updated on all the logical CPUs in the domain. This was not spelled out clearly in the spec earlier. The specification has been updated and the updated document, "AMD64 Technology Platform Quality of Service Extensions Publication # 56375 Revision: 1.02 Issue Date: October 2020" is available now. Refer the section: Code and Data Prioritization. Fix the issue by adding a new flag arch_has_per_cpu_cfg in rdt_cache data structure. The documentation can be obtained at: https://developer.amd.com/wp-content/resources/56375.pdf Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 [ bp: Massage commit message. ] Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/160675180380.15628.3309402017215002347.stgit@bmoger-ubuntu
2020-11-27x86/mce: Do not overwrite no_way_out if mce_end() failsGabriele Paoloni
Currently, if mce_end() fails, no_way_out - the variable denoting whether the machine can recover from this MCE - is determined by whether the worst severity that was found across the MCA banks associated with the current CPU, is of panic severity. However, at this point no_way_out could have been already set by mca_start() after looking at all severities of all CPUs that entered the MCE handler. If mce_end() fails, check first if no_way_out is already set and, if so, stick to it, otherwise use the local worst value. [ bp: Massage. ] Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201127161819.3106432-2-gabriele.paoloni@intel.com
2020-11-25x86/speculation: Fix prctl() when spectre_v2_user={seccomp,prctl},ibpbAnand K Mistry
When spectre_v2_user={seccomp,prctl},ibpb is specified on the command line, IBPB is force-enabled and STIPB is conditionally-enabled (or not available). However, since 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") the spectre_v2_user_ibpb variable is set to SPECTRE_V2_USER_{PRCTL,SECCOMP} instead of SPECTRE_V2_USER_STRICT, which is the actual behaviour. Because the issuing of IBPB relies on the switch_mm_*_ibpb static branches, the mitigations behave as expected. Since 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") this discrepency caused the misreporting of IB speculation via prctl(). On CPUs with STIBP always-on and spectre_v2_user=seccomp,ibpb, prctl(PR_GET_SPECULATION_CTRL) would return PR_SPEC_PRCTL | PR_SPEC_ENABLE instead of PR_SPEC_DISABLE since both IBPB and STIPB are always on. It also allowed prctl(PR_SET_SPECULATION_CTRL) to set the IB speculation mode, even though the flag is ignored. Similarly, for CPUs without SMT, prctl(PR_GET_SPECULATION_CTRL) should also return PR_SPEC_DISABLE since IBPB is always on and STIBP is not available. [ bp: Massage commit message. ] Fixes: 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") Fixes: 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201110123349.1.Id0cbf996d2151f4c143c90f9028651a5b49a5908@changeid
2020-11-24x86/resctrl: Add necessary kernfs_put() calls to prevent refcount leakXiaochen Shen
On resource group creation via a mkdir an extra kernfs_node reference is obtained by kernfs_get() to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. Currently the extra kernfs_node reference count is only dropped by kernfs_put() in rdtgroup_kn_unlock() while the rdtgroup structure is removed in a few other locations that lack the matching reference drop. In call paths of rmdir and umount, when a control group is removed, kernfs_remove() is called to remove the whole kernfs nodes tree of the control group (including the kernfs nodes trees of all child monitoring groups), and then rdtgroup structure is freed by kfree(). The rdtgroup structures of all child monitoring groups under the control group are freed by kfree() in free_all_child_rdtgrp(). Before calling kfree() to free the rdtgroup structures, the kernfs node of the control group itself as well as the kernfs nodes of all child monitoring groups still take the extra references which will never be dropped to 0 and the kernfs nodes will never be freed. It leads to reference count leak and kernfs_node_cache memory leak. For example, reference count leak is observed in these two cases: (1) mount -t resctrl resctrl /sys/fs/resctrl mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 umount /sys/fs/resctrl (2) mkdir /sys/fs/resctrl/c1 mkdir /sys/fs/resctrl/c1/mon_groups/m1 rmdir /sys/fs/resctrl/c1 The same reference count leak issue also exists in the error exit paths of mkdir in mkdir_rdt_prepare() and rdtgroup_mkdir_ctrl_mon(). Fix this issue by following changes to make sure the extra kernfs_node reference on rdtgroup is dropped before freeing the rdtgroup structure. (1) Introduce rdtgroup removal helper rdtgroup_remove() to wrap up kernfs_put() and kfree(). (2) Call rdtgroup_remove() in rdtgroup removal path where the rdtgroup structure is about to be freed by kfree(). (3) Call rdtgroup_remove() or kernfs_put() as appropriate in the error exit paths of mkdir where an extra reference is taken by kernfs_get(). Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085088-31707-1-git-send-email-xiaochen.shen@intel.com
2020-11-24x86/resctrl: Remove superfluous kernfs_get() calls to prevent refcount leakXiaochen Shen
Willem reported growing of kernfs_node_cache entries in slabtop when repeatedly creating and removing resctrl subdirectories as well as when repeatedly mounting and unmounting the resctrl filesystem. On resource group (control as well as monitoring) creation via a mkdir an extra kernfs_node reference is obtained to ensure that the rdtgroup structure remains accessible for the rdtgroup_kn_unlock() calls where it is removed on deletion. The kernfs_node reference count is dropped by kernfs_put() in rdtgroup_kn_unlock(). With the above explaining the need for one kernfs_get()/kernfs_put() pair in resctrl there are more places where a kernfs_node reference is obtained without a corresponding release. The excessive amount of reference count on kernfs nodes will never be dropped to 0 and the kernfs nodes will never be freed in the call paths of rmdir and umount. It leads to reference count leak and kernfs_node_cache memory leak. Remove the superfluous kernfs_get() calls and expand the existing comments surrounding the remaining kernfs_get()/kernfs_put() pair that remains in use. Superfluous kernfs_get() calls are removed from two areas: (1) In call paths of mount and mkdir, when kernfs nodes for "info", "mon_groups" and "mon_data" directories and sub-directories are created, the reference count of newly created kernfs node is set to 1. But after kernfs_create_dir() returns, superfluous kernfs_get() are called to take an additional reference. (2) kernfs_get() calls in rmdir call paths. Fixes: 17eafd076291 ("x86/intel_rdt: Split resource group removal in two") Fixes: 4af4a88e0c92 ("x86/intel_rdt/cqm: Add mount,umount support") Fixes: f3cbeacaa06e ("x86/intel_rdt/cqm: Add rmdir support") Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data") Fixes: c7d9aac61311 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring") Fixes: 5dc1d5c6bac2 ("x86/intel_rdt: Simplify info and base file lists") Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system") Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Willem de Bruijn <willemb@google.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1604085053-31639-1-git-send-email-xiaochen.shen@intel.com
2020-11-24x86/sgx: Fix sgx_ioc_enclave_provision() kernel-doc commentBorislav Petkov
Fix ./arch/x86/kernel/cpu/sgx/ioctl.c:666: warning: Function parameter or member \ 'encl' not described in 'sgx_ioc_enclave_provision' ./arch/x86/kernel/cpu/sgx/ioctl.c:666: warning: Excess function parameter \ 'enclave' description in 'sgx_ioc_enclave_provision' Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201123181922.0c009406@canb.auug.org.au
2020-11-21x86/mce, cper: Pass x86 CPER through the MCA handling chainSmita Koralahalli
The kernel uses ACPI Boot Error Record Table (BERT) to report fatal errors that occurred in a previous boot. The MCA errors in the BERT are reported using the x86 Processor Error Common Platform Error Record (CPER) format. Currently, the record prints out the raw MSR values and AMD relies on the raw record to provide MCA information. Extract the raw MSR values of MCA registers from the BERT and feed them into mce_log() to decode them properly. The implementation is SMCA-specific as the raw MCA register values are given in the register offset order of the SMCA address space. [ bp: Massage. ] [ Fix a build breakage in patch v1. ] Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Punit Agrawal <punit1.agrawal@toshiba.co.jp> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lkml.kernel.org/r/20201119182938.151155-1-Smita.KoralahalliChannabasappa@amd.com
2020-11-19Merge branches 'cpuinfo.2020.11.06a', 'doc.2020.11.06a', ↵Paul E. McKenney
'fixes.2020.11.19b', 'lockdep.2020.11.02a', 'tasks.2020.11.06a' and 'torture.2020.11.06a' into HEAD cpuinfo.2020.11.06a: Speedups for /proc/cpuinfo. doc.2020.11.06a: Documentation updates. fixes.2020.11.19b: Miscellaneous fixes. lockdep.2020.11.02a: Lockdep-RCU updates to avoid "unused variable". tasks.2020.11.06a: Tasks-RCU updates. torture.2020.11.06a': Torture-test updates.
2020-11-19x86/smpboot: Move rcu_cpu_starting() earlierPaul E. McKenney
The call to rcu_cpu_starting() in mtrr_ap_init() is not early enough in the CPU-hotplug onlining process, which results in lockdep splats as follows: ============================= WARNING: suspicious RCU usage 5.9.0+ #268 Not tainted ----------------------------- kernel/kprobes.c:300 RCU-list traversed in non-reader section!! other info that might help us debug this: RCU used illegally from offline CPU! rcu_scheduler_active = 1, debug_locks = 1 no locks held by swapper/1/0. stack backtrace: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0+ #268 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: dump_stack+0x77/0x97 __is_insn_slot_addr+0x15d/0x170 kernel_text_address+0xba/0xe0 ? get_stack_info+0x22/0xa0 __kernel_text_address+0x9/0x30 show_trace_log_lvl+0x17d/0x380 ? dump_stack+0x77/0x97 dump_stack+0x77/0x97 __lock_acquire+0xdf7/0x1bf0 lock_acquire+0x258/0x3d0 ? vprintk_emit+0x6d/0x2c0 _raw_spin_lock+0x27/0x40 ? vprintk_emit+0x6d/0x2c0 vprintk_emit+0x6d/0x2c0 printk+0x4d/0x69 start_secondary+0x1c/0x100 secondary_startup_64_no_verify+0xb8/0xbb This is avoided by moving the call to rcu_cpu_starting up near the beginning of the start_secondary() function. Note that the raw_smp_processor_id() is required in order to avoid calling into lockdep before RCU has declared the CPU to be watched for readers. Link: https://lore.kernel.org/lkml/160223032121.7002.1269740091547117869.tip-bot2@tip-bot2/ Reported-by: Qian Cai <cai@redhat.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-19x86/resctrl: Constify kernfs_opsRikard Falkeborn
The only usage of the kf_ops field in the rftype struct is to pass it as argument to __kernfs_create_file(), which accepts a pointer to const. Make it a pointer to const. This makes it possible to make rdtgroup_kf_single_ops and kf_mondata_ops const, which allows the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lkml.kernel.org/r/20201110230228.801785-1-rikard.falkeborn@gmail.com
2020-11-19x86/topology: Set cpu_die_id only if DIE_TYPE foundYazen Ghannam
CPUID Leaf 0x1F defines a DIE_TYPE level (nb: ECX[8:15] level type == 0x5), but CPUID Leaf 0xB does not. However, detect_extended_topology() will set struct cpuinfo_x86.cpu_die_id regardless of whether a valid Die ID was found. Only set cpu_die_id if a DIE_TYPE level is found. CPU topology code may use another value for cpu_die_id, e.g. the AMD NodeId on AMD-based systems. Code ordering should be maintained so that the CPUID Leaf 0x1F Die ID value will take precedence on systems that may use another value. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201109210659.754018-5-Yazen.Ghannam@amd.com
2020-11-19x86/CPU/AMD: Remove amd_get_nb_id()Yazen Ghannam
The Last Level Cache ID is returned by amd_get_nb_id(). In practice, this value is the same as the AMD NodeId for callers of this function. The NodeId is saved in struct cpuinfo_x86.cpu_die_id. Replace calls to amd_get_nb_id() with the logical CPU's cpu_die_id and remove the function. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201109210659.754018-3-Yazen.Ghannam@amd.com
2020-11-19x86/CPU/AMD: Save AMD NodeId as cpu_die_idYazen Ghannam
AMD systems provide a "NodeId" value that represents a global ID indicating to which "Node" a logical CPU belongs. The "Node" is a physical structure equivalent to a Die, and it should not be confused with logical structures like NUMA nodes. Logical nodes can be adjusted based on firmware or other settings whereas the physical nodes/dies are fixed based on hardware topology. The NodeId value can be used when a physical ID is needed by software. Save the AMD NodeId to struct cpuinfo_x86.cpu_die_id. Use the value from CPUID or MSR as appropriate. Default to phys_proc_id otherwise. Do so for both AMD and Hygon systems. Drop the node_id parameter from cacheinfo_*_init_llc_id() as it is no longer needed. Update the x86 topology documentation. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201109210659.754018-2-Yazen.Ghannam@amd.com
2020-11-19x86/sgx: Return -ERESTARTSYS in sgx_ioc_enclave_add_pages()Jarkko Sakkinen
Return -ERESTARTSYS instead of -EINTR in sgx_ioc_enclave_add_pages() when interrupted before any pages have been processed. At this point ioctl can be obviously safely restarted. Reported-by: Haitao Huang <haitao.huang@intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201118213932.63341-1-jarkko@kernel.org