- 14 11月, 2018 2 次提交
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由 Jim Mattson 提交于
[ Upstream commit cfb634fe ] According to volume 3 of the SDM, bits 63:15 and 12:4 of the exit qualification field for debug exceptions are reserved (cleared to 0). However, the SDM is incorrect about bit 16 (corresponding to DR6.RTM). This bit should be set if a debug exception (#DB) or a breakpoint exception (#BP) occurred inside an RTM region while advanced debugging of RTM transactional regions was enabled. Note that this is the opposite of DR6.RTM, which "indicates (when clear) that a debug exception (#DB) or breakpoint exception (#BP) occurred inside an RTM region while advanced debugging of RTM transactional regions was enabled." There is still an issue with stale DR6 bits potentially being misreported for the current debug exception. DR6 should not have been modified before vectoring the #DB exception, and the "new DR6 bits" should be available somewhere, but it was and they aren't. Fixes: b96fb439 ("KVM: nVMX: fixes to nested virt interrupt injection") Signed-off-by: NJim Mattson <jmattson@google.com> Reviewed-by: NSean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NSasha Levin <sashal@kernel.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit f77084d96355f5fba8e2c1fb3a51a393b1570de7 upstream. The WARN_ON_ONCE(__read_cr3() != build_cr3()) in switch_mm_irqs_off() triggers every once in a while during a snapshotted system upgrade. The warning triggers since commit decab088 ("x86/mm: Remove preempt_disable/enable() from __native_flush_tlb()"). The callchain is: get_page_from_freelist() -> post_alloc_hook() -> __kernel_map_pages() with CONFIG_DEBUG_PAGEALLOC enabled. Disable preemption during CR3 reset / __flush_tlb_all() and add a comment why preemption has to be disabled so it won't be removed accidentaly. Add another preemptible() check in __flush_tlb_all() to catch callers with enabled preemption when PGE is enabled, because PGE enabled does not trigger the warning in __native_flush_tlb(). Suggested by Andy Lutomirski. Fixes: decab088 ("x86/mm: Remove preempt_disable/enable() from __native_flush_tlb()") Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181017103432.zgv46nlu3hc7k4rq@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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- 17 10月, 2018 1 次提交
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x86/fpu: Fix i486 + no387 boot crash by only saving FPU registers on context switch if there is an FPU Booting an i486 with "no387 nofxsr" ends with with the following crash: math_emulate: 0060:c101987d Kernel panic - not syncing: Math emulation needed in kernel on the first context switch in user land. The reason is that copy_fpregs_to_fpstate() tries FNSAVE which does not work as the FPU is turned off. This bug was introduced in: f1c8cd01 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active") Add a check for X86_FEATURE_FPU before trying to save FPU registers (we have such a check in switch_fpu_finish() already). Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: NAndy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: f1c8cd01 ("x86/fpu: Change fpu->fpregs_active users to fpu->fpstate_active") Link: http://lkml.kernel.org/r/20181016202525.29437-4-bigeasy@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 14 10月, 2018 1 次提交
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由 Peter Zijlstra 提交于
Eric reported that a sequence count loop using this_cpu_read() got optimized out. This is wrong, this_cpu_read() must imply READ_ONCE() because the interface is IRQ-safe, therefore an interrupt can have changed the per-cpu value. Fixes: 7c3576d2 ("[PATCH] i386: Convert PDA into the percpu section") Reported-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NEric Dumazet <edumazet@google.com> Cc: hpa@zytor.com Cc: eric.dumazet@gmail.com Cc: bp@alien8.de Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20181011104019.748208519@infradead.org
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- 10 10月, 2018 1 次提交
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由 Jan Kara 提交于
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a result we will see warnings such as: BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067 addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0 file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null) CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased) Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018 Call Trace: dump_stack+0x5a/0x75 print_bad_pte+0x217/0x2c0 ? enqueue_task_fair+0x76/0x9f0 _vm_normal_page+0xe5/0x100 zap_pte_range+0x148/0x740 unmap_page_range+0x39a/0x4b0 unmap_vmas+0x42/0x90 unmap_region+0x99/0xf0 ? vma_gap_callbacks_rotate+0x1a/0x20 do_munmap+0x255/0x3a0 vm_munmap+0x54/0x80 SyS_munmap+0x1d/0x30 do_syscall_64+0x74/0x150 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 ... when mprotect(2) gets used on DAX mappings. Also there is a wide variety of other failures that can result from the missing _PAGE_DEVMAP flag when the area gets used by get_user_pages() later. Fix the problem by including _PAGE_DEVMAP in a set of flags that get preserved by mprotect(2). Fixes: 69660fd7 ("x86, mm: introduce _PAGE_DEVMAP") Fixes: ebd31197 ("powerpc/mm: Add devmap support for ppc64") Cc: <stable@vger.kernel.org> Signed-off-by: NJan Kara <jack@suse.cz> Acked-by: NMichal Hocko <mhocko@suse.com> Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de> Signed-off-by: NDan Williams <dan.j.williams@intel.com>
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- 03 10月, 2018 1 次提交
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由 Mike Travis 提交于
Introduce is_early_uv_system() which uses efi.uv_systab to decide early in the boot process whether the kernel runs on a UV system. This is needed to skip other early setup/init code that might break the UV platform if done too early such as before necessary ACPI tables parsing takes place. Suggested-by: NHedi Berriche <hedi.berriche@hpe.com> Signed-off-by: NMike Travis <mike.travis@hpe.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NRuss Anderson <rja@hpe.com> Reviewed-by: NDimitri Sivanich <sivanich@hpe.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Len Brown <len.brown@intel.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Xiaoming Gao <gxm.linux.kernel@gmail.com> Cc: Rajvi Jingar <rajvi.jingar@intel.com> Link: https://lkml.kernel.org/r/20181002180144.801700401@stormcage.americas.sgi.com
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- 02 10月, 2018 1 次提交
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由 Natarajan, Janakarajan 提交于
In Family 17h, some L3 Cache Performance events require the ThreadMask and SliceMask to be set. For other events, these fields do not affect the count either way. Set ThreadMask and SliceMask to 0xFF and 0xF respectively. Signed-off-by: NJanakarajan Natarajan <Janakarajan.Natarajan@amd.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H . Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Suravee <Suravee.Suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/Message-ID: Signed-off-by: NIngo Molnar <mingo@kernel.org>
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- 21 9月, 2018 1 次提交
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由 Feng Tang 提交于
We met a kernel panic when enabling earlycon, which is due to the fixmap address of earlycon is not statically setup. Currently the static fixmap setup in head_64.S only covers 2M virtual address space, while it actually could be in 4M space with different kernel configurations, e.g. when VSYSCALL emulation is disabled. So increase the static space to 4M for now by defining FIXMAP_PMD_NUM to 2, and add a build time check to ensure that the fixmap is covered by the initial static page tables. Fixes: 1ad83c85 ("x86_64,vsyscall: Make vsyscall emulation configurable") Suggested-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NFeng Tang <feng.tang@intel.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Tested-by: Nkernel test robot <rong.a.chen@intel.com> Reviewed-by: Juergen Gross <jgross@suse.com> (Xen parts) Cc: H Peter Anvin <hpa@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180920025828.23699-1-feng.tang@intel.com
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- 20 9月, 2018 4 次提交
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由 Drew Schmitt 提交于
Add KVM_CAP_MSR_PLATFORM_INFO so that userspace can disable guest access to reads of MSR_PLATFORM_INFO. Disabling access to reads of this MSR gives userspace the control to "expose" this platform-dependent information to guests in a clear way. As it exists today, guests that read this MSR would get unpopulated information if userspace hadn't already set it (and prior to this patch series, only the CPUID faulting information could have been populated). This existing interface could be confusing if guests don't handle the potential for incorrect/incomplete information gracefully (e.g. zero reported for base frequency). Signed-off-by: NDrew Schmitt <dasch@google.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Liran Alon 提交于
In case L1 do not intercept L2 HLT or enter L2 in HLT activity-state, it is possible for a vCPU to be blocked while it is in guest-mode. According to Intel SDM 26.6.5 Interrupt-Window Exiting and Virtual-Interrupt Delivery: "These events wake the logical processor if it just entered the HLT state because of a VM entry". Therefore, if L1 enters L2 in HLT activity-state and L2 has a pending deliverable interrupt in vmcs12->guest_intr_status.RVI, then the vCPU should be waken from the HLT state and injected with the interrupt. In addition, if while the vCPU is blocked (while it is in guest-mode), it receives a nested posted-interrupt, then the vCPU should also be waken and injected with the posted interrupt. To handle these cases, this patch enhances kvm_vcpu_has_events() to also check if there is a pending interrupt in L2 virtual APICv provided by L1. That is, it evaluates if there is a pending virtual interrupt for L2 by checking RVI[7:4] > VPPR[7:4] as specified in Intel SDM 29.2.1 Evaluation of Pending Interrupts. Note that this also handles the case of nested posted-interrupt by the fact RVI is updated in vmx_complete_nested_posted_interrupt() which is called from kvm_vcpu_check_block() -> kvm_arch_vcpu_runnable() -> kvm_vcpu_running() -> vmx_check_nested_events() -> vmx_complete_nested_posted_interrupt(). Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com> Reviewed-by: NDarren Kenny <darren.kenny@oracle.com> Signed-off-by: NLiran Alon <liran.alon@oracle.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Vitaly Kuznetsov 提交于
These structures are going to be used from KVM code so let's make their names reflect their Hyper-V origin. Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com> Acked-by: NK. Y. Srinivasan <kys@microsoft.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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由 Sean Christopherson 提交于
A VMX preemption timer value of '0' is guaranteed to cause a VMExit prior to the CPU executing any instructions in the guest. Use the preemption timer (if it's supported) to trigger immediate VMExit in place of the current method of sending a self-IPI. This ensures that pending VMExit injection to L1 occurs prior to executing any instructions in the guest (regardless of nesting level). When deferring VMExit injection, KVM generates an immediate VMExit from the (possibly nested) guest by sending itself an IPI. Because hardware interrupts are blocked prior to VMEnter and are unblocked (in hardware) after VMEnter, this results in taking a VMExit(INTR) before any guest instruction is executed. But, as this approach relies on the IPI being received before VMEnter executes, it only works as intended when KVM is running as L0. Because there are no architectural guarantees regarding when IPIs are delivered, when running nested the INTR may "arrive" long after L2 is running e.g. L0 KVM doesn't force an immediate switch to L1 to deliver an INTR. For the most part, this unintended delay is not an issue since the events being injected to L1 also do not have architectural guarantees regarding their timing. The notable exception is the VMX preemption timer[1], which is architecturally guaranteed to cause a VMExit prior to executing any instructions in the guest if the timer value is '0' at VMEnter. Specifically, the delay in injecting the VMExit causes the preemption timer KVM unit test to fail when run in a nested guest. Note: this approach is viable even on CPUs with a broken preemption timer, as broken in this context only means the timer counts at the wrong rate. There are no known errata affecting timer value of '0'. [1] I/O SMIs also have guarantees on when they arrive, but I have no idea if/how those are emulated in KVM. Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> [Use a hook for SVM instead of leaving the default in x86.c - Paolo] Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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- 16 9月, 2018 1 次提交
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由 Brijesh Singh 提交于
kvmclock defines few static variables which are shared with the hypervisor during the kvmclock initialization. When SEV is active, memory is encrypted with a guest-specific key, and if the guest OS wants to share the memory region with the hypervisor then it must clear the C-bit before sharing it. Currently, we use kernel_physical_mapping_init() to split large pages before clearing the C-bit on shared pages. But it fails when called from the kvmclock initialization (mainly because the memblock allocator is not ready that early during boot). Add a __bss_decrypted section attribute which can be used when defining such shared variable. The so-defined variables will be placed in the .bss..decrypted section. This section will be mapped with C=0 early during boot. The .bss..decrypted section has a big chunk of memory that may be unused when memory encryption is not active, free it when memory encryption is not active. Suggested-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Radim Krčmář<rkrcmar@redhat.com> Cc: kvm@vger.kernel.org Link: https://lkml.kernel.org/r/1536932759-12905-2-git-send-email-brijesh.singh@amd.com
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- 14 9月, 2018 1 次提交
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由 Joerg Roedel 提交于
This reverts commit 1f40a46c. It turned out that this patch is not sufficient to enable PTI on 32 bit systems with legacy 2-level page-tables. In this paging mode the huge-page PTEs are in the top-level page-table directory, where also the mirroring to the user-space page-table happens. So every huge PTE exits twice, in the kernel and in the user page-table. That means that accessed/dirty bits need to be fetched from two PTEs in this mode to be safe, but this is not trivial to implement because it needs changes to generic code just for the sake of enabling PTI with 32-bit legacy paging. As all systems that need PTI should support PAE anyway, remove support for PTI when 32-bit legacy paging is used. Fixes: 7757d607 ('x86/pti: Allow CONFIG_PAGE_TABLE_ISOLATION for x86_32') Reported-by: NMeelis Roos <mroos@linux.ee> Signed-off-by: NJoerg Roedel <jroedel@suse.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Link: https://lkml.kernel.org/r/1536922754-31379-1-git-send-email-joro@8bytes.org
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- 08 9月, 2018 2 次提交
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由 Nadav Amit 提交于
When page-table entries are set, the compiler might optimize their assignment by using multiple instructions to set the PTE. This might turn into a security hazard if the user somehow manages to use the interim PTE. L1TF does not make our lives easier, making even an interim non-present PTE a security hazard. Using WRITE_ONCE() to set PTEs and friends should prevent this potential security hazard. I skimmed the differences in the binary with and without this patch. The differences are (obviously) greater when CONFIG_PARAVIRT=n as more code optimizations are possible. For better and worse, the impact on the binary with this patch is pretty small. Skimming the code did not cause anything to jump out as a security hazard, but it seems that at least move_soft_dirty_pte() caused set_pte_at() to use multiple writes. Signed-off-by: NNadav Amit <namit@vmware.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180902181451.80520-1-namit@vmware.com
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由 Wanpeng Li 提交于
Dan Carpenter reported that the untrusted data returns from kvm_register_read() results in the following static checker warning: arch/x86/kvm/lapic.c:576 kvm_pv_send_ipi() error: buffer underflow 'map->phys_map' 's32min-s32max' KVM guest can easily trigger this by executing the following assembly sequence in Ring0: mov $10, %rax mov $0xFFFFFFFF, %rbx mov $0xFFFFFFFF, %rdx mov $0, %rsi vmcall As this will cause KVM to execute the following code-path: vmx_handle_exit() -> handle_vmcall() -> kvm_emulate_hypercall() -> kvm_pv_send_ipi() which will reach out-of-bounds access. This patch fixes it by adding a check to kvm_pv_send_ipi() against map->max_apic_id, ignoring destinations that are not present and delivering the rest. We also check whether or not map->phys_map[min + i] is NULL since the max_apic_id is set to the max apic id, some phys_map maybe NULL when apic id is sparse, especially kvm unconditionally set max_apic_id to 255 to reserve enough space for any xAPIC ID. Reported-by: NDan Carpenter <dan.carpenter@oracle.com> Reviewed-by: NLiran Alon <liran.alon@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Liran Alon <liran.alon@oracle.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: NWanpeng Li <wanpengli@tencent.com> [Add second "if (min > map->max_apic_id)" to complete the fix. -Radim] Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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- 07 9月, 2018 1 次提交
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由 Marc Zyngier 提交于
kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to deal with. Drop the now obsolete code. Fixes: fb1522e0 ("KVM: update to new mmu_notifier semantic v2") Cc: James Hogan <jhogan@kernel.org> Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com> Signed-off-by: NChristoffer Dall <christoffer.dall@arm.com>
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- 06 9月, 2018 1 次提交
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由 Jann Horn 提交于
When the kernel.print-fatal-signals sysctl has been enabled, a simple userspace crash will cause the kernel to write a crash dump that contains, among other things, the kernel gsbase into dmesg. As suggested by Andy, limit output to pt_regs, FS_BASE and KERNEL_GS_BASE in this case. This also moves the bitness-specific logic from show_regs() into process_{32,64}.c. Fixes: 45807a1d ("vdso: print fatal signals") Signed-off-by: NJann Horn <jannh@google.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180831194151.123586-1-jannh@google.com
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- 03 9月, 2018 1 次提交
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由 Randy Dunlap 提交于
Fix kernel-doc warnings in arch/x86/include/asm/atomic.h that are caused by having a #define macro between the kernel-doc notation and the function name. Fixed by moving the #define macro to after the function implementation. Make the same change for atomic64_{32,64}.h for consistency even though there were no kernel-doc warnings found in these header files, but there would be if they were used in generation of documentation. Fixes these kernel-doc warnings: ../arch/x86/include/asm/atomic.h:84: warning: Excess function parameter 'i' description in 'arch_atomic_sub_and_test' ../arch/x86/include/asm/atomic.h:84: warning: Excess function parameter 'v' description in 'arch_atomic_sub_and_test' ../arch/x86/include/asm/atomic.h:96: warning: Excess function parameter 'v' description in 'arch_atomic_inc' ../arch/x86/include/asm/atomic.h:109: warning: Excess function parameter 'v' description in 'arch_atomic_dec' ../arch/x86/include/asm/atomic.h:124: warning: Excess function parameter 'v' description in 'arch_atomic_dec_and_test' ../arch/x86/include/asm/atomic.h:138: warning: Excess function parameter 'v' description in 'arch_atomic_inc_and_test' ../arch/x86/include/asm/atomic.h:153: warning: Excess function parameter 'i' description in 'arch_atomic_add_negative' ../arch/x86/include/asm/atomic.h:153: warning: Excess function parameter 'v' description in 'arch_atomic_add_negative' Fixes: 18cc1814 ("atomics/treewide: Make test ops optional") Signed-off-by: NRandy Dunlap <rdunlap@infradead.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/0a1e678d-c8c5-b32c-2640-ed4e94d399d2@infradead.org
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- 02 9月, 2018 1 次提交
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由 Samuel Neves 提交于
In the __getcpu function, lsl is using the wrong target and destination registers. Luckily, the compiler tends to choose %eax for both variables, so it has been working so far. Fixes: a582c540 ("x86/vdso: Use RDPID in preference to LSL when available") Signed-off-by: NSamuel Neves <sneves@dei.uc.pt> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NAndy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180901201452.27828-1-sneves@dei.uc.pt
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- 31 8月, 2018 2 次提交
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由 Andy Lutomirski 提交于
A NMI can hit in the middle of context switching or in the middle of switch_mm_irqs_off(). In either case, CR3 might not match current->mm, which could cause copy_from_user_nmi() and friends to read the wrong memory. Fix it by adding a new nmi_uaccess_okay() helper and checking it in copy_from_user_nmi() and in __copy_from_user_nmi()'s callers. Signed-off-by: NAndy Lutomirski <luto@kernel.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NRik van Riel <riel@surriel.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/dd956eba16646fd0b15c3c0741269dfd84452dac.1535557289.git.luto@kernel.org
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由 Jann Horn 提交于
show_opcodes() is used both for dumping kernel instructions and for dumping user instructions. If userspace causes #PF by jumping to a kernel address, show_opcodes() can be reached with regs->ip controlled by the user, pointing to kernel code. Make sure that userspace can't trick us into dumping kernel memory into dmesg. Fixes: 7cccf072 ("x86/dumpstack: Add a show_ip() function") Signed-off-by: NJann Horn <jannh@google.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NKees Cook <keescook@chromium.org> Reviewed-by: NBorislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: security@kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180828154901.112726-1-jannh@google.com
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- 30 8月, 2018 7 次提交
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由 Sean Christopherson 提交于
Allowing x86_emulate_instruction() to be called directly has led to subtle bugs being introduced, e.g. not setting EMULTYPE_NO_REEXECUTE in the emulation type. While most of the blame lies on re-execute being opt-out, exporting x86_emulate_instruction() also exposes its cr2 parameter, which may have contributed to commit d391f120 ("x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested") using x86_emulate_instruction() instead of emulate_instruction() because "hey, I have a cr2!", which in turn introduced its EMULTYPE_NO_REEXECUTE bug. Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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由 Sean Christopherson 提交于
Lack of the kvm_ prefix gives the impression that it's a VMX or SVM specific function, and there's no conflict that prevents adding the kvm_ prefix. Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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由 Sean Christopherson 提交于
retry_instruction() and reexecute_instruction() are a package deal, i.e. there is no scenario where one is allowed and the other is not. Merge their controlling emulation type flags to enforce this in code. Name the combined flag EMULTYPE_ALLOW_RETRY to make it abundantly clear that we are allowing re{try,execute} to occur, as opposed to explicitly requesting retry of a previously failed instruction. Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Cc: stable@vger.kernel.org Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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由 Sean Christopherson 提交于
Re-execution of an instruction after emulation decode failure is intended to be used only when emulating shadow page accesses. Invert the flag to make allowing re-execution opt-in since that behavior is by far in the minority. Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Cc: stable@vger.kernel.org Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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由 Sean Christopherson 提交于
Re-execution after an emulation decode failure is only intended to handle a case where two or vCPUs race to write a shadowed page, i.e. we should never re-execute an instruction as part of RSM emulation. Add a new helper, kvm_emulate_instruction_from_buffer(), to support emulating from a pre-defined buffer. This eliminates the last direct call to x86_emulate_instruction() outside of kvm_mmu_page_fault(), which means x86_emulate_instruction() can be unexported in a future patch. Fixes: 7607b717 ("KVM: SVM: install RSM intercept") Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Cc: stable@vger.kernel.org Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
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由 Uros Bizjak 提交于
Replace open-coded set instructions with CC_SET()/CC_OUT(). Signed-off-by: NUros Bizjak <ubizjak@gmail.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180814165951.13538-1-ubizjak@gmail.com
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由 Nick Desaulniers 提交于
This should have been marked extern inline in order to pick up the out of line definition in arch/x86/kernel/irqflags.S. Fixes: 208cbb32 ("x86/irqflags: Provide a declaration for native_save_fl") Reported-by: NBen Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: NNick Desaulniers <ndesaulniers@google.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NJuergen Gross <jgross@suse.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180827214011.55428-1-ndesaulniers@google.com
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- 28 8月, 2018 1 次提交
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由 Juergen Gross 提交于
Using only 32-bit writes for the pte will result in an intermediate L1TF vulnerable PTE. When running as a Xen PV guest this will at once switch the guest to shadow mode resulting in a loss of performance. Use arch_atomic64_xchg() instead which will perform the requested operation atomically with all 64 bits. Some performance considerations according to: https://software.intel.com/sites/default/files/managed/ad/dc/Intel-Xeon-Scalable-Processor-throughput-latency.pdf The main number should be the latency, as there is no tight loop around native_ptep_get_and_clear(). "lock cmpxchg8b" has a latency of 20 cycles, while "lock xchg" (with a memory operand) isn't mentioned in that document. "lock xadd" (with xadd having 3 cycles less latency than xchg) has a latency of 11, so we can assume a latency of 14 for "lock xchg". Signed-off-by: NJuergen Gross <jgross@suse.com> Reviewed-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NJan Beulich <jbeulich@suse.com> Tested-by: NJason Andryuk <jandryuk@gmail.com> Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
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- 27 8月, 2018 1 次提交
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由 Andi Kleen 提交于
On Nehalem and newer core CPUs the CPU cache internally uses 44 bits physical address space. The L1TF workaround is limited by this internal cache address width, and needs to have one bit free there for the mitigation to work. Older client systems report only 36bit physical address space so the range check decides that L1TF is not mitigated for a 36bit phys/32GB system with some memory holes. But since these actually have the larger internal cache width this warning is bogus because it would only really be needed if the system had more than 43bits of memory. Add a new internal x86_cache_bits field. Normally it is the same as the physical bits field reported by CPUID, but for Nehalem and newerforce it to be at least 44bits. Change the L1TF memory size warning to use the new cache_bits field to avoid bogus warnings and remove the bogus comment about memory size. Fixes: 17dbca11 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Reported-by: NGeorge Anchev <studio@anchev.net> Reported-by: NChristopher Snowhill <kode54@gmail.com> Signed-off-by: NAndi Kleen <ak@linux.intel.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: Michael Hocko <mhocko@suse.com> Cc: vbabka@suse.cz Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180824170351.34874-1-andi@firstfloor.org
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- 24 8月, 2018 2 次提交
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由 Vlastimil Babka 提交于
Two users have reported [1] that they have an "extremely unlikely" system with more than MAX_PA/2 memory and L1TF mitigation is not effective. In fact it's a CPU with 36bits phys limit (64GB) and 32GB memory, but due to holes in the e820 map, the main region is almost 500MB over the 32GB limit: [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000081effffff] usable Suggestions to use 'mem=32G' to enable the L1TF mitigation while losing the 500MB revealed, that there's an off-by-one error in the check in l1tf_select_mitigation(). l1tf_pfn_limit() returns the last usable pfn (inclusive) and the range check in the mitigation path does not take this into account. Instead of amending the range check, make l1tf_pfn_limit() return the first PFN which is over the limit which is less error prone. Adjust the other users accordingly. [1] https://bugzilla.suse.com/show_bug.cgi?id=1105536 Fixes: 17dbca11 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Reported-by: NGeorge Anchev <studio@anchev.net> Reported-by: NChristopher Snowhill <kode54@gmail.com> Signed-off-by: NVlastimil Babka <vbabka@suse.cz> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180823134418.17008-1-vbabka@suse.cz
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由 Peter Zijlstra 提交于
If we don't use paravirt; don't play unnecessary and complicated games to free page-tables. Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NRik van Riel <riel@surriel.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 23 8月, 2018 2 次提交
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由 Peter Zijlstra 提交于
Revert commits: 95b0e635 x86/mm/tlb: Always use lazy TLB mode 64482aaf x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs ac031589 x86/mm/tlb: Make lazy TLB mode lazier 61d0beb5 x86/mm/tlb: Restructure switch_mm_irqs_off() 2ff6ddf1 x86/mm/tlb: Leave lazy TLB mode at page table free time In order to simplify the TLB invalidate fixes for x86 and unify the parts that need backporting. We'll try again later. Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NRik van Riel <riel@surriel.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Ard Biesheuvel 提交于
An ordinary arm64 defconfig build has ~64 KB worth of __ksymtab entries, each consisting of two 64-bit fields containing absolute references, to the symbol itself and to a char array containing its name, respectively. When we build the same configuration with KASLR enabled, we end up with an additional ~192 KB of relocations in the .init section, i.e., one 24 byte entry for each absolute reference, which all need to be processed at boot time. Given how the struct kernel_symbol that describes each entry is completely local to module.c (except for the references emitted by EXPORT_SYMBOL() itself), we can easily modify it to contain two 32-bit relative references instead. This reduces the size of the __ksymtab section by 50% for all 64-bit architectures, and gets rid of the runtime relocations entirely for architectures implementing KASLR, either via standard PIE linking (arm64) or using custom host tools (x86). Note that the binary search involving __ksymtab contents relies on each section being sorted by symbol name. This is implemented based on the input section names, not the names in the ksymtab entries, so this patch does not interfere with that. Given that the use of place-relative relocations requires support both in the toolchain and in the module loader, we cannot enable this feature for all architectures. So make it dependent on whether CONFIG_HAVE_ARCH_PREL32_RELOCATIONS is defined. Link: http://lkml.kernel.org/r/20180704083651.24360-4-ard.biesheuvel@linaro.orgSigned-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: NJessica Yu <jeyu@kernel.org> Acked-by: NMichael Ellerman <mpe@ellerman.id.au> Reviewed-by: NWill Deacon <will.deacon@arm.com> Acked-by: NIngo Molnar <mingo@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morris <james.morris@microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 22 8月, 2018 1 次提交
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由 Sean Christopherson 提交于
Hardware support for basic SGX virtualization adds a new execution control (ENCLS_EXITING), VMCS field (ENCLS_EXITING_BITMAP) and exit reason (ENCLS), that enables a VMM to intercept specific ENCLS leaf functions, e.g. to inject faults when the VMM isn't exposing SGX to a VM. When ENCLS_EXITING is enabled, the VMM can set/clear bits in the bitmap to intercept/allow ENCLS leaf functions in non-root, e.g. setting bit 2 in the ENCLS_EXITING_BITMAP will cause ENCLS[EINIT] to VMExit(ENCLS). Note: EXIT_REASON_ENCLS was previously added by commit 1f519992 ("KVM: VMX: add missing exit reasons"). Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20180814163334.25724-2-sean.j.christopherson@intel.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
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- 21 8月, 2018 4 次提交
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由 Juergen Gross 提交于
Remove Xen hypercall functions which are used nowhere in the kernel. Signed-off-by: NJuergen Gross <jgross@suse.com> Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
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由 Dan Williams 提交于
Currently memory_failure() returns zero if the error was handled. On that result mce_unmap_kpfn() is called to zap the page out of the kernel linear mapping to prevent speculative fetches of potentially poisoned memory. However, in the case of dax mapped devmap pages the page may be in active permanent use by the device driver, so it cannot be unmapped from the kernel. Instead of marking the page not present, marking the page UC should be sufficient for preventing poison from being pre-fetched into the cache. Convert mce_unmap_pfn() to set_mce_nospec() remapping the page as UC, to hide it from speculative accesses. Given that that persistent memory errors can be cleared by the driver, include a facility to restore the page to cacheable operation, clear_mce_nospec(). Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: <linux-edac@vger.kernel.org> Cc: <x86@kernel.org> Acked-by: NTony Luck <tony.luck@intel.com> Signed-off-by: NDan Williams <dan.j.williams@intel.com> Acked-by: NIngo Molnar <mingo@redhat.com> Signed-off-by: NDave Jiang <dave.jiang@intel.com>
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由 Vlastimil Babka 提交于
On 32bit PAE kernels on 64bit hardware with enough physical bits, l1tf_pfn_limit() will overflow unsigned long. This in turn affects max_swapfile_size() and can lead to swapon returning -EINVAL. This has been observed in a 32bit guest with 42 bits physical address size, where max_swapfile_size() overflows exactly to 1 << 32, thus zero, and produces the following warning to dmesg: [ 6.396845] Truncating oversized swap area, only using 0k out of 2047996k Fix this by using unsigned long long instead. Fixes: 17dbca11 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Fixes: 377eeaa8 ("x86/speculation/l1tf: Limit swap file size to MAX_PA/2") Reported-by: NDominique Leuenberger <dimstar@suse.de> Reported-by: NAdrian Schroeter <adrian@suse.de> Signed-off-by: NVlastimil Babka <vbabka@suse.cz> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NAndi Kleen <ak@linux.intel.com> Acked-by: NMichal Hocko <mhocko@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180820095835.5298-1-vbabka@suse.cz
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由 Arnd Bergmann 提交于
Without linux/irq.h, there is no declaration of notifier_block, leading to a build warning: In file included from arch/x86/kernel/cpu/mcheck/threshold.c:10: arch/x86/include/asm/mce.h:151:46: error: 'struct notifier_block' declared inside parameter list will not be visible outside of this definition or declaration [-Werror] It's sufficient to declare the struct tag here, which avoids pulling in more header files. Fixes: 447ae316 ("x86: Don't include linux/irq.h from asm/hardirq.h") Signed-off-by: NArnd Bergmann <arnd@arndb.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Cc: Nicolai Stange <nstange@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20180817100156.3009043-1-arnd@arndb.de
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