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2020-07-22x86/ioperm: Fix io bitmap invalidation on Xen PVAndy Lutomirski3-0/+22
commit cadfad870154e14f745ec845708bc17d166065f2 upstream. tss_invalidate_io_bitmap() wasn't wired up properly through the pvop machinery, so the TSS and Xen's io bitmap would get out of sync whenever disabling a valid io bitmap. Add a new pvop for tss_invalidate_io_bitmap() to fix it. This is XSA-329. Fixes: 22fe5b0439dd ("x86/ioperm: Move TSS bitmap update to exit to user work") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/d53075590e1f91c19f8af705059d3ff99424c020.1595030016.git.luto@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22x86/fpu: Reset MXCSR to default in kernel_fpu_begin()Petteri Aimonen1-0/+5
[ Upstream commit 7ad816762f9bf89e940e618ea40c43138b479e10 ] Previously, kernel floating point code would run with the MXCSR control register value last set by userland code by the thread that was active on the CPU core just before kernel call. This could affect calculation results if rounding mode was changed, or a crash if a FPU/SIMD exception was unmasked. Restore MXCSR to the kernel's default value. [ bp: Carve out from a bigger patch by Petteri, add feature check, add FNINIT call too (amluto). ] Signed-off-by: Petteri Aimonen <jpa@git.mail.kapsi.fi> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://bugzilla.kernel.org/show_bug.cgi?id=207979 Link: https://lkml.kernel.org/r/20200624114646.28953-2-bp@alien8.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-16x86/entry: Increase entry_stack size to a full pagePeter Zijlstra1-1/+1
[ Upstream commit c7aadc09321d8f9a1d3bd1e6d8a47222ecddf6c5 ] Marco crashed in bad_iret with a Clang11/KCSAN build due to overflowing the stack. Now that we run C code on it, expand it to a full page. Suggested-by: Andy Lutomirski <luto@amacapital.net> Reported-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com> Tested-by: Marco Elver <elver@google.com> Link: https://lkml.kernel.org/r/20200618144801.819246178@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeupSean Christopherson1-0/+5
commit 5d5103595e9e53048bb7e70ee2673c897ab38300 upstream. Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case where firmware doesn't initialize or save/restore across S3. This fixes a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON taking a #GP due to VMX not being fully enabled, i.e. breaks KVM. Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals with the case where the MSR is locked, and because APs already redo init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being used to reinitialize APs upon wakeup. Do the call in the early wakeup flow to avoid dependencies in the syscore_ops chain, e.g. simply adding a resume hook is not guaranteed to work, as KVM does VMXON in its own resume hook, kvm_resume(), when KVM has active guests. Fixes: 21bd3467a58e ("KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR") Reported-by: Brad Campbell <lists2009@fnarfbargle.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Tested-by: Brad Campbell <lists2009@fnarfbargle.com> Cc: stable@vger.kernel.org # v5.6 Link: https://lkml.kernel.org/r/20200608174134.11157-1-sean.j.christopherson@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30KVM: VMX: Stop context switching MSR_IA32_UMWAIT_CONTROLSean Christopherson1-2/+0
commit bf09fb6cba4f7099620cc9ed32d94c27c4af992e upstream. Remove support for context switching between the guest's and host's desired UMWAIT_CONTROL. Propagating the guest's value to hardware isn't required for correct functionality, e.g. KVM intercepts reads and writes to the MSR, and the latency effects of the settings controlled by the MSR are not architecturally visible. As a general rule, KVM should not allow the guest to control power management settings unless explicitly enabled by userspace, e.g. see KVM_CAP_X86_DISABLE_EXITS. E.g. Intel's SDM explicitly states that C0.2 can improve the performance of SMT siblings. A devious guest could disable C0.2 so as to improve the performance of their workloads at the detriment to workloads running in the host or on other VMs. Wholesale removal of UMWAIT_CONTROL context switching also fixes a race condition where updates from the host may cause KVM to enter the guest with the incorrect value. Because updates are are propagated to all CPUs via IPI (SMP function callback), the value in hardware may be stale with respect to the cached value and KVM could enter the guest with the wrong value in hardware. As above, the guest can't observe the bad value, but it's a weird and confusing wart in the implementation. Removal also fixes the unnecessary usage of VMX's atomic load/store MSR lists. Using the lists is only necessary for MSRs that are required for correct functionality immediately upon VM-Enter/VM-Exit, e.g. EFER on old hardware, or for MSRs that need to-the-uop precision, e.g. perf related MSRs. For UMWAIT_CONTROL, the effects are only visible in the kernel via TPAUSE/delay(), and KVM doesn't do any form of delay in vcpu_vmx_run(). Using the atomic lists is undesirable as they are more expensive than direct RDMSR/WRMSR. Furthermore, even if giving the guest control of the MSR is legitimate, e.g. in pass-through scenarios, it's not clear that the benefits would outweigh the overhead. E.g. saving and restoring an MSR across a VMX roundtrip costs ~250 cycles, and if the guest diverged from the host that cost would be paid on every run of the guest. In other words, if there is a legitimate use case then it should be enabled by a new per-VM capability. Note, KVM still needs to emulate MSR_IA32_UMWAIT_CONTROL so that it can correctly expose other WAITPKG features to the guest, e.g. TPAUSE, UMWAIT and UMONITOR. Fixes: 6e3ba4abcea56 ("KVM: vmx: Emulate MSR IA32_UMWAIT_CONTROL") Cc: stable@vger.kernel.org Cc: Jingqi Liu <jingqi.liu@intel.com> Cc: Tao Xu <tao3.xu@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200623005135.10414-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30KVM: nVMX: Plumb L2 GPA through to PML emulationSean Christopherson1-1/+1
commit 2dbebf7ae1ed9a420d954305e2c9d5ed39ec57c3 upstream. Explicitly pass the L2 GPA to kvm_arch_write_log_dirty(), which for all intents and purposes is vmx_write_pml_buffer(), instead of having the latter pull the GPA from vmcs.GUEST_PHYSICAL_ADDRESS. If the dirty bit update is the result of KVM emulation (rare for L2), then the GPA in the VMCS may be stale and/or hold a completely unrelated GPA. Fixes: c5f983f6e8455 ("nVMX: Implement emulated Page Modification Logging") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200622215832.22090-2-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30x86/resctrl: Support CPUID enumeration of MBM counter widthReinette Chatre1-1/+2
[ Upstream commit f3d44f18b0662327c42128b9d3604489bdb6e36f ] The original Memory Bandwidth Monitoring (MBM) architectural definition defines counters of up to 62 bits in the IA32_QM_CTR MSR while the first-generation MBM implementation uses statically defined 24 bit counters. Expand the MBM CPUID enumeration properties to include the MBM counter width. The previously undefined EAX output register contains, in bits [7:0], the MBM counter width encoded as an offset from 24 bits. Enumerating this property is only specified for Intel CPUs. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/afa3af2f753f6bc301fb743bc8944e749cb24afa.1588715690.git.reinette.chatre@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30x86/cpu: Move resctrl CPUID code to resctrl/Reinette Chatre1-0/+3
[ Upstream commit 0118ad82c2a64ebcf15d7565ed35361407efadfa ] The function determining a platform's support and properties of cache occupancy and memory bandwidth monitoring (properties of X86_FEATURE_CQM_LLC) can be found among the common CPU code. After the feature's properties is populated in the per-CPU data the resctrl subsystem is the only consumer (via boot_cpu_data). Move the function that obtains the CPU information used by resctrl to the resctrl subsystem and rename it from init_cqm() to resctrl_cpu_detect(). The function continues to be called from the common CPU code. This move is done in preparation of the addition of some vendor specific code. No functional change. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/38433b99f9d16c8f4ee796f8cc42b871531fa203.1588715690.git.reinette.chatre@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22x86,smap: Fix smap_{save,restore}() alternativesPeter Zijlstra1-3/+8
[ Upstream commit 1ff865e343c2b59469d7e41d370a980a3f972c71 ] As reported by objtool: lib/ubsan.o: warning: objtool: .altinstr_replacement+0x0: alternative modifies stack lib/ubsan.o: warning: objtool: .altinstr_replacement+0x7: alternative modifies stack the smap_{save,restore}() alternatives violate (the newly enforced) rule on stack invariance. That is, due to there only being a single ORC table it must be valid to any alternative. These alternatives violate this with the direct result that unwinds will not be correct when it hits between the PUSH and POP instructions. Rewrite the functions to only have a conditional jump. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20200429101802.GI13592@hirez.programming.kicks-ass.net Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-17x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisonedTony Luck1-6/+13
commit 17fae1294ad9d711b2c3dd0edef479d40c76a5e8 upstream. An interesting thing happened when a guest Linux instance took a machine check. The VMM unmapped the bad page from guest physical space and passed the machine check to the guest. Linux took all the normal actions to offline the page from the process that was using it. But then guest Linux crashed because it said there was a second machine check inside the kernel with this stack trace: do_memory_failure set_mce_nospec set_memory_uc _set_memory_uc change_page_attr_set_clr cpa_flush clflush_cache_range_opt This was odd, because a CLFLUSH instruction shouldn't raise a machine check (it isn't consuming the data). Further investigation showed that the VMM had passed in another machine check because is appeared that the guest was accessing the bad page. Fix is to check the scope of the poison by checking the MCi_MISC register. If the entire page is affected, then unmap the page. If only part of the page is affected, then mark the page as uncacheable. This assumes that VMMs will do the logical thing and pass in the "whole page scope" via the MCi_MISC register (since they unmapped the entire page). [ bp: Adjust to x86/entry changes. ] Fixes: 284ce4011ba6 ("x86/memory_failure: Introduce {set, clear}_mce_nospec()") Reported-by: Jue Wang <juew@google.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jue Wang <juew@google.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200520163546.GA7977@agluck-desk2.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-17x86/vdso: Unbreak paravirt VDSO clocksThomas Gleixner1-0/+18
commit 7778d8417b74aded842eeb372961cfc460417fa0 upstream. The conversion of x86 VDSO to the generic clock mode storage broke the paravirt and hyperv clocksource logic. These clock sources have their own internal sequence counter to validate the clocksource at the point of reading it. This is necessary because the hypervisor can invalidate the clocksource asynchronously so a check during the VDSO data update is not sufficient. If the internal check during read invalidates the clocksource the read return U64_MAX. The original code checked this efficiently by testing whether the result (casted to signed) is negative, i.e. bit 63 is set. This was done that way because an extra indicator for the validity had more overhead. The conversion broke this check because the check was replaced by a check for a valid VDSO clock mode. The wreckage manifests itself when the paravirt clock is installed as a valid VDSO clock and during runtime invalidated by the hypervisor, e.g. after a host suspend/resume cycle. After the invalidation the read function returns U64_MAX which is used as cycles and makes the clock jump by ~2200 seconds, and become stale until the 2200 seconds have elapsed where it starts to jump again. The period of this effect depends on the shift/mult pair of the clocksource and the jumps and staleness are an artifact of undefined but reproducible behaviour of math overflow. Implement an x86 version of the new vdso_cycles_ok() inline which adds this check back and a variant of vdso_clocksource_ok() which lets the compiler optimize it out to avoid the extra conditional. That's suboptimal when the system does not have a VDSO capable clocksource, but that's not the case which is optimized for. Fixes: 5d51bee725cc ("clocksource: Add common vdso clock mode storage") Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Miklos Szeredi <mszeredi@redhat.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200606221532.080560273@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-10x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigationMark Gross2-0/+6
commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-10x86/cpu: Add a steppings field to struct x86_cpu_idMark Gross1-3/+24
commit e9d7144597b10ff13ff2264c059f7d4a7fbc89ac upstream Intel uses the same family/model for several CPUs. Sometimes the stepping must be checked to tell them apart. On x86 there can be at most 16 steppings. Add a steppings bitmask to x86_cpu_id and a X86_MATCH_VENDOR_FAMILY_MODEL_STEPPING_FEATURE macro and support for matching against family/model/stepping. [ bp: Massage. ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-07mm: Fix mremap not considering huge pmd devmapFan Yang1-0/+1
commit 5bfea2d9b17f1034a68147a8b03b9789af5700f9 upstream. The original code in mm/mremap.c checks huge pmd by: if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { However, a DAX mapped nvdimm is mapped as huge page (by default) but it is not transparent huge page (_PAGE_PSE | PAGE_DEVMAP). This commit changes the condition to include the case. This addresses CVE-2020-10757. Fixes: 5c7fb56e5e3f ("mm, dax: dax-pmd vs thp-pmd vs hugetlbfs-pmd") Cc: <stable@vger.kernel.org> Reported-by: Fan Yang <Fan_Yang@sjtu.edu.cn> Signed-off-by: Fan Yang <Fan_Yang@sjtu.edu.cn> Tested-by: Fan Yang <Fan_Yang@sjtu.edu.cn> Tested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-31Merge tag 'x86-urgent-2020-05-31' of ↵Linus Torvalds2-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A pile of x86 fixes: - Prevent a memory leak in ioperm which was caused by the stupid assumption that the exit cleanup is always called for current, which is not the case when fork fails after taking a reference on the ioperm bitmap. - Fix an arithmething overflow in the DMA code on 32bit systems - Fill gaps in the xstate copy with defaults instead of leaving them uninitialized - Revert: "Make __X32_SYSCALL_BIT be unsigned long" as it turned out that existing user space fails to build" * tag 'x86-urgent-2020-05-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ioperm: Prevent a memory leak when fork fails x86/dma: Fix max PFN arithmetic overflow on 32 bit systems copy_xstate_to_kernel(): don't leave parts of destination uninitialized x86/syscalls: Revert "x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long"
2020-05-28x86/ioperm: Prevent a memory leak when fork failsJay Lang1-2/+2
In the copy_process() routine called by _do_fork(), failure to allocate a PID (or further along in the function) will trigger an invocation to exit_thread(). This is done to clean up from an earlier call to copy_thread_tls(). Naturally, the child task is passed into exit_thread(), however during the process, io_bitmap_exit() nullifies the parent's io_bitmap rather than the child's. As copy_thread_tls() has been called ahead of the failure, the reference count on the calling thread's io_bitmap is incremented as we would expect. However, io_bitmap_exit() doesn't accept any arguments, and thus assumes it should trash the current thread's io_bitmap reference rather than the child's. This is pretty sneaky in practice, because in all instances but this one, exit_thread() is called with respect to the current task and everything works out. A determined attacker can issue an appropriate ioctl (i.e. KDENABIO) to get a bitmap allocated, and force a clone3() syscall to fail by passing in a zeroed clone_args structure. The kernel handles the erroneous struct and the buggy code path is followed, and even though the parent's reference to the io_bitmap is trashed, the child still holds a reference and thus the structure will never be freed. Fix this by tweaking io_bitmap_exit() and its subroutines to accept a task_struct argument which to operate on. Fixes: ea5f1cd7ab49 ("x86/ioperm: Remove bitmap if all permissions dropped") Signed-off-by: Jay Lang <jaytlang@mit.edu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable#@vger.kernel.org Link: https://lkml.kernel.org/r/20200524162742.253727-1-jaytlang@mit.edu
2020-05-28x86/dma: Fix max PFN arithmetic overflow on 32 bit systemsAlexander Dahl1-1/+1
The intermediate result of the old term (4UL * 1024 * 1024 * 1024) is 4 294 967 296 or 0x100000000 which is no problem on 64 bit systems. The patch does not change the later overall result of 0x100000 for MAX_DMA32_PFN (after it has been shifted by PAGE_SHIFT). The new calculation yields the same result, but does not require 64 bit arithmetic. On 32 bit systems the old calculation suffers from an arithmetic overflow in that intermediate term in braces: 4UL aka unsigned long int is 4 byte wide and an arithmetic overflow happens (the 0x100000000 does not fit in 4 bytes), the in braces result is truncated to zero, the following right shift does not alter that, so MAX_DMA32_PFN evaluates to 0 on 32 bit systems. That wrong value is a problem in a comparision against MAX_DMA32_PFN in the init code for swiotlb in pci_swiotlb_detect_4gb() to decide if swiotlb should be active. That comparison yields the opposite result, when compiling on 32 bit systems. This was not possible before 1b7e03ef7570 ("x86, NUMA: Enable emulation on 32bit too") when that MAX_DMA32_PFN was first made visible to x86_32 (and which landed in v3.0). In practice this wasn't a problem, unless CONFIG_SWIOTLB is active on x86-32. However if one has set CONFIG_IOMMU_INTEL, since c5a5dc4cbbf4 ("iommu/vt-d: Don't switch off swiotlb if bounce page is used") there's a dependency on CONFIG_SWIOTLB, which was not necessarily active before. That landed in v5.4, where we noticed it in the fli4l Linux distribution. We have CONFIG_IOMMU_INTEL active on both 32 and 64 bit kernel configs there (I could not find out why, so let's just say historical reasons). The effect is at boot time 64 MiB (default size) were allocated for bounce buffers now, which is a noticeable amount of memory on small systems like pcengines ALIX 2D3 with 256 MiB memory, which are still frequently used as home routers. We noticed this effect when migrating from kernel v4.19 (LTS) to v5.4 (LTS) in fli4l and got that kernel messages for example: Linux version 5.4.22 (buildroot@buildroot) (gcc version 7.3.0 (Buildroot 2018.02.8)) #1 SMP Mon Nov 26 23:40:00 CET 2018 … Memory: 183484K/261756K available (4594K kernel code, 393K rwdata, 1660K rodata, 536K init, 456K bss , 78272K reserved, 0K cma-reserved, 0K highmem) … PCI-DMA: Using software bounce buffering for IO (SWIOTLB) software IO TLB: mapped [mem 0x0bb78000-0x0fb78000] (64MB) The initial analysis and the suggested fix was done by user 'sourcejedi' at stackoverflow and explicitly marked as GPLv2 for inclusion in the Linux kernel: https://unix.stackexchange.com/a/520525/50007 The new calculation, which does not suffer from that overflow, is the same as for arch/mips now as suggested by Robin Murphy. The fix was tested by fli4l users on round about two dozen different systems, including both 32 and 64 bit archs, bare metal and virtualized machines. [ bp: Massage commit message. ] Fixes: 1b7e03ef7570 ("x86, NUMA: Enable emulation on 32bit too") Reported-by: Alan Jenkins <alan.christopher.jenkins@gmail.com> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Alexander Dahl <post@lespocky.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://unix.stackexchange.com/q/520065/50007 Link: https://web.nettworks.org/bugs/browse/FFL-2560 Link: https://lkml.kernel.org/r/20200526175749.20742-1-post@lespocky.de
2020-05-27x86: Hide the archdata.iommu field behind generic IOMMU_APIKrzysztof Kozlowski1-1/+1
There is a generic, kernel wide configuration symbol for enabling the IOMMU specific bits: CONFIG_IOMMU_API. Implementations (including INTEL_IOMMU and AMD_IOMMU driver) select it so use it here as well. This makes the conditional archdata.iommu field consistent with other platforms and also fixes any compile test builds of other IOMMU drivers, when INTEL_IOMMU or AMD_IOMMU are not selected). For the case when INTEL_IOMMU/AMD_IOMMU and COMPILE_TEST are not selected, this should create functionally equivalent code/choice. With COMPILE_TEST this field could appear if other IOMMU drivers are chosen but neither INTEL_IOMMU nor AMD_IOMMU are not. Reported-by: kbuild test robot <lkp@intel.com> Fixes: e93a1695d7fb ("iommu: Enable compile testing for some of drivers") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20200518120855.27822-2-krzk@kernel.org Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-05-23x86: bitops: fix build regressionNick Desaulniers1-6/+6
This is easily reproducible via CC=clang + CONFIG_STAGING=y + CONFIG_VT6656=m. It turns out that if your config tickles __builtin_constant_p via differences in choices to inline or not, these statements produce invalid assembly: $ cat foo.c long a(long b, long c) { asm("orb %1, %0" : "+q"(c): "r"(b)); return c; } $ gcc foo.c foo.c: Assembler messages: foo.c:2: Error: `%rax' not allowed with `orb' Use the `%b` "x86 Operand Modifier" to instead force register allocation to select a lower-8-bit GPR operand. The "q" constraint only has meaning on -m32 otherwise is treated as "r". Not all GPRs have low-8-bit aliases for -m32. Fixes: 1651e700664b4 ("x86: Fix bitops.h warning with a moved cast") Reported-by: kernelci.org bot <bot@kernelci.org> Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Suggested-by: Brian Gerst <brgerst@gmail.com> Suggested-by: H. Peter Anvin <hpa@zytor.com> Suggested-by: Ilie Halip <ilie.halip@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com> [build, clang-11] Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-By: Brian Gerst <brgerst@gmail.com> Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Marco Elver <elver@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Daniel Axtens <dja@axtens.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Link: http://lkml.kernel.org/r/20200508183230.229464-1-ndesaulniers@google.com Link: https://github.com/ClangBuiltLinux/linux/issues/961 Link: https://lore.kernel.org/lkml/20200504193524.GA221287@google.com/ Link: https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#x86Operandmodifiers Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-17Merge tag 'x86_urgent_for_v5.7-rc7' of ↵Linus Torvalds1-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fix from Borislav Petkov: "A single fix for early boot crashes of kernels built with gcc10 and stack protector enabled" * tag 'x86_urgent_for_v5.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix early boot crash on gcc-10, third try
2020-05-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-2/+2
Pull kvm fixes from Paolo Bonzini: "A new testcase for guest debugging (gdbstub) that exposed a bunch of bugs, mostly for AMD processors. And a few other x86 fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Fix off-by-one error in kvm_vcpu_ioctl_x86_setup_mce KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.c KVM: SVM: Disable AVIC before setting V_IRQ KVM: Introduce kvm_make_all_cpus_request_except() KVM: VMX: pass correct DR6 for GD userspace exit KVM: x86, SVM: isolate vcpu->arch.dr6 from vmcb->save.dr6 KVM: SVM: keep DR6 synchronized with vcpu->arch.dr6 KVM: nSVM: trap #DB and #BP to userspace if guest debugging is on KVM: selftests: Add KVM_SET_GUEST_DEBUG test KVM: X86: Fix single-step with KVM_SET_GUEST_DEBUG KVM: X86: Set RTM for DB_VECTOR too for KVM_EXIT_DEBUG KVM: x86: fix DR6 delivery for various cases of #DB injection KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly
2020-05-15x86: Fix early boot crash on gcc-10, third tryBorislav Petkov1-1/+6
... or the odyssey of trying to disable the stack protector for the function which generates the stack canary value. The whole story started with Sergei reporting a boot crash with a kernel built with gcc-10: Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 Call Trace: dump_stack panic ? start_secondary __stack_chk_fail start_secondary secondary_startup_64 -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary This happens because gcc-10 tail-call optimizes the last function call in start_secondary() - cpu_startup_entry() - and thus emits a stack canary check which fails because the canary value changes after the boot_init_stack_canary() call. To fix that, the initial attempt was to mark the one function which generates the stack canary with: __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) however, using the optimize attribute doesn't work cumulatively as the attribute does not add to but rather replaces previously supplied optimization options - roughly all -fxxx options. The key one among them being -fno-omit-frame-pointer and thus leading to not present frame pointer - frame pointer which the kernel needs. The next attempt to prevent compilers from tail-call optimizing the last function call cpu_startup_entry(), shy of carving out start_secondary() into a separate compilation unit and building it with -fno-stack-protector, was to add an empty asm(""). This current solution was short and sweet, and reportedly, is supported by both compilers but we didn't get very far this time: future (LTO?) optimization passes could potentially eliminate this, which leads us to the third attempt: having an actual memory barrier there which the compiler cannot ignore or move around etc. That should hold for a long time, but hey we said that about the other two solutions too so... Reported-by: Sergei Trofimovich <slyfox@gentoo.org> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Kalle Valo <kvalo@codeaurora.org> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
2020-05-14Merge tag 'trace-v5.7-rc5' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing fixes from Steven Rostedt: "Various tracing fixes: - Fix a crash when having function tracing and function stack tracing on the command line. The ftrace trampolines are created as executable and read only. But the stack tracer tries to modify them with text_poke() which expects all kernel text to still be writable at boot. Keep the trampolines writable at boot, and convert them to read-only with the rest of the kernel. - A selftest was triggering in the ring buffer iterator code, that is no longer valid with the update of keeping the ring buffer writable while a iterator is reading. Just bail after three failed attempts to get an event and remove the warning and disabling of the ring buffer. - While modifying the ring buffer code, decided to remove all the unnecessary BUG() calls" * tag 'trace-v5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer: Remove all BUG() calls ring-buffer: Don't deactivate the ring buffer on failed iterator reads x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot up
2020-05-13KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.cBabu Moger1-0/+1
Though rdpkru and wrpkru are contingent upon CR4.PKE, the PKRU resource isn't. It can be read with XSAVE and written with XRSTOR. So, if we don't set the guest PKRU value here(kvm_load_guest_xsave_state), the guest can read the host value. In case of kvm_load_host_xsave_state, guest with CR4.PKE clear could potentially use XRSTOR to change the host PKRU value. While at it, move pkru state save/restore to common code and the host_pkru field to kvm_vcpu_arch. This will let SVM support protection keys. Cc: stable@vger.kernel.org Reported-by: Jim Mattson <jmattson@google.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Message-Id: <158932794619.44260.14508381096663848853.stgit@naples-babu.amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-13x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot upSteven Rostedt (VMware)1-0/+6
Booting one of my machines, it triggered the following crash: Kernel/User page tables isolation: enabled ftrace: allocating 36577 entries in 143 pages Starting tracer 'function' BUG: unable to handle page fault for address: ffffffffa000005c #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 2014067 P4D 2014067 PUD 2015063 PMD 7b253067 PTE 7b252061 Oops: 0003 [#1] PREEMPT SMP PTI CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.0-test+ #24 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 RIP: 0010:text_poke_early+0x4a/0x58 Code: 34 24 48 89 54 24 08 e8 bf 72 0b 00 48 8b 34 24 48 8b 4c 24 08 84 c0 74 0b 48 89 df f3 a4 48 83 c4 10 5b c3 9c 58 fa 48 89 df <f3> a4 50 9d 48 83 c4 10 5b e9 d6 f9 ff ff 0 41 57 49 RSP: 0000:ffffffff82003d38 EFLAGS: 00010046 RAX: 0000000000000046 RBX: ffffffffa000005c RCX: 0000000000000005 RDX: 0000000000000005 RSI: ffffffff825b9a90 RDI: ffffffffa000005c RBP: ffffffffa000005c R08: 0000000000000000 R09: ffffffff8206e6e0 R10: ffff88807b01f4c0 R11: ffffffff8176c106 R12: ffffffff8206e6e0 R13: ffffffff824f2440 R14: 0000000000000000 R15: ffffffff8206eac0 FS: 0000000000000000(0000) GS:ffff88807d400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffa000005c CR3: 0000000002012000 CR4: 00000000000006b0 Call Trace: text_poke_bp+0x27/0x64 ? mutex_lock+0x36/0x5d arch_ftrace_update_trampoline+0x287/0x2d5 ? ftrace_replace_code+0x14b/0x160 ? ftrace_update_ftrace_func+0x65/0x6c __register_ftrace_function+0x6d/0x81 ftrace_startup+0x23/0xc1 register_ftrace_function+0x20/0x37 func_set_flag+0x59/0x77 __set_tracer_option.isra.19+0x20/0x3e trace_set_options+0xd6/0x13e apply_trace_boot_options+0x44/0x6d register_tracer+0x19e/0x1ac early_trace_init+0x21b/0x2c9 start_kernel+0x241/0x518 ? load_ucode_intel_bsp+0x21/0x52 secondary_startup_64+0xa4/0xb0 I was able to trigger it on other machines, when I added to the kernel command line of both "ftrace=function" and "trace_options=func_stack_trace". The cause is the "ftrace=function" would register the function tracer and create a trampoline, and it will set it as executable and read-only. Then the "trace_options=func_stack_trace" would then update the same trampoline to include the stack tracer version of the function tracer. But since the trampoline already exists, it updates it with text_poke_bp(). The problem is that text_poke_bp() called while system_state == SYSTEM_BOOTING, it will simply do a memcpy() and not the page mapping, as it would think that the text is still read-write. But in this case it is not, and we take a fault and crash. Instead, lets keep the ftrace trampolines read-write during boot up, and then when the kernel executable text is set to read-only, the ftrace trampolines get set to read-only as well. Link: https://lkml.kernel.org/r/20200430202147.4dc6e2de@oasis.local.home Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: stable@vger.kernel.org Fixes: 768ae4406a5c ("x86/ftrace: Use text_poke()") Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-05-10Merge tag 'x86-urgent-2020-05-10' of ↵Linus Torvalds2-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes for x86: - Ensure that direct mapping alias is always flushed when changing page attributes. The optimization for small ranges failed to do so when the virtual address was in the vmalloc or module space. - Unbreak the trace event registration for syscalls without arguments caused by the refactoring of the SYSCALL_DEFINE0() macro. - Move the printk in the TSC deadline timer code to a place where it is guaranteed to only be called once during boot and cannot be rearmed by clearing warn_once after boot. If it's invoked post boot then lockdep rightfully complains about a potential deadlock as the calling context is different. - A series of fixes for objtool and the ORC unwinder addressing variety of small issues: - Stack offset tracking for indirect CFAs in objtool ignored subsequent pushs and pops - Repair the unwind hints in the register clearing entry ASM code - Make the unwinding in the low level exit to usermode code stop after switching to the trampoline stack. The unwind hint is no longer valid and the ORC unwinder emits a warning as it can't find the registers anymore. - Fix unwind hints in switch_to_asm() and rewind_stack_do_exit() which caused objtool to generate bogus ORC data. - Prevent unwinder warnings when dumping the stack of a non-current task as there is no way to be sure about the validity because the dumped stack can be a moving target. - Make the ORC unwinder behave the same way as the frame pointer unwinder when dumping an inactive tasks stack and do not skip the first frame. - Prevent ORC unwinding before ORC data has been initialized - Immediately terminate unwinding when a unknown ORC entry type is found. - Prevent premature stop of the unwinder caused by IRET frames. - Fix another infinite loop in objtool caused by a negative offset which was not catched. - Address a few build warnings in the ORC unwinder and add missing static/ro_after_init annotations" * tag 'x86-urgent-2020-05-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/unwind/orc: Move ORC sorting variables under !CONFIG_MODULES x86/apic: Move TSC deadline timer debug printk ftrace/x86: Fix trace event registration for syscalls without arguments x86/mm/cpa: Flush direct map alias during cpa objtool: Fix infinite loop in for_offset_range() x86/unwind/orc: Fix premature unwind stoppage due to IRET frames x86/unwind/orc: Fix error path for bad ORC entry type x86/unwind/orc: Prevent unwinding before ORC initialization x86/unwind/orc: Don't skip the first frame for inactive tasks x86/unwind: Prevent false warnings for non-current tasks x86/unwind/orc: Convert global variables to static x86/entry/64: Fix unwind hints in rewind_stack_do_exit() x86/entry/64: Fix unwind hints in __switch_to_asm() x86/entry/64: Fix unwind hints in kernel exit path x86/entry/64: Fix unwind hints in register clearing code objtool: Fix stack offset tracking for indirect CFAs
2020-05-08KVM: x86, SVM: isolate vcpu->arch.dr6 from vmcb->save.dr6Paolo Bonzini1-2/+0
There are two issues with KVM_EXIT_DEBUG on AMD, whose root cause is the different handling of DR6 on intercepted #DB exceptions on Intel and AMD. On Intel, #DB exceptions transmit the DR6 value via the exit qualification field of the VMCS, and the exit qualification only contains the description of the precise event that caused a vmexit. On AMD, instead the DR6 field of the VMCB is filled in as if the #DB exception was to be injected into the guest. This has two effects when guest debugging is in use: * the guest DR6 is clobbered * the kvm_run->debug.arch.dr6 field can accumulate more debug events, rather than just the last one that happened (the testcase in the next patch covers this issue). This patch fixes both issues by emulating, so to speak, the Intel behavior on AMD processors. The important observation is that (after the previous patches) the VMCB value of DR6 is only ever observable from the guest is KVM_DEBUGREG_WONT_EXIT is set. Therefore we can actually set vmcb->save.dr6 to any value we want as long as KVM_DEBUGREG_WONT_EXIT is clear, which it will be if guest debugging is enabled. Therefore it is possible to enter the guest with an all-zero DR6, reconstruct the #DB payload from the DR6 we get at exit time, and let kvm_deliver_exception_payload move the newly set bits into vcpu->arch.dr6. Some extra bits may be included in the payload if KVM_DEBUGREG_WONT_EXIT is set, but this is harmless. This may not be the most optimized way to deal with this, but it is simple and, being confined within SVM code, it gets rid of the set_dr6 callback and kvm_update_dr6. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-08KVM: SVM: keep DR6 synchronized with vcpu->arch.dr6Paolo Bonzini1-1/+1
kvm_x86_ops.set_dr6 is only ever called with vcpu->arch.dr6 as the second argument. Ensure that the VMCB value is synchronized to vcpu->arch.dr6 on #DB (both "normal" and nested) and nested vmentry, so that the current value of DR6 is always available in vcpu->arch.dr6. The get_dr6 callback can just access vcpu->arch.dr6 and becomes redundant. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-07Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-2/+2
Pull kvm fixes from Paolo Bonzini: "Bugfixes, mostly for ARM and AMD, and more documentation. Slightly bigger than usual because I couldn't send out what was pending for rc4, but there is nothing worrisome going on. I have more fixes pending for guest debugging support (gdbstub) but I will send them next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits) KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly KVM: selftests: Fix build for evmcs.h kvm: x86: Use KVM CPU capabilities to determine CR4 reserved bits KVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path docs/virt/kvm: Document configuring and running nested guests KVM: s390: Remove false WARN_ON_ONCE for the PQAP instruction kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts KVM: x86: Fixes posted interrupt check for IRQs delivery modes KVM: SVM: fill in kvm_run->debug.arch.dr[67] KVM: nVMX: Replace a BUG_ON(1) with BUG() to squash clang warning KVM: arm64: Fix 32bit PC wrap-around KVM: arm64: vgic-v4: Initialize GICv4.1 even in the absence of a virtual ITS KVM: arm64: Save/restore sp_el0 as part of __guest_enter KVM: arm64: Delete duplicated label in invalid_vector KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi() KVM: arm64: vgic-v3: Retire all pending LPIs on vcpu destroy KVM: arm: vgic-v2: Only use the virtual state when userspace accesses pending bits KVM: arm: vgic: Only use the virtual state when userspace accesses enable bits KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read KVM: arm64: PSCI: Forbid 64bit functions for 32bit guests ...
2020-05-07KVM: x86: fix DR6 delivery for various cases of #DB injectionPaolo Bonzini1-0/+1
Go through kvm_queue_exception_p so that the payload is correctly delivered through the exit qualification, and add a kvm_update_dr6 call to kvm_deliver_exception_payload that is needed on AMD. Reported-by: Peter Xu <peterx@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-04KVM: x86: Fixes posted interrupt check for IRQs delivery modesSuravee Suthikulpanit1-2/+2
Current logic incorrectly uses the enum ioapic_irq_destination_types to check the posted interrupt destination types. However, the value was set using APIC_DM_XXX macros, which are left-shifted by 8 bits. Fixes by using the APIC_DM_FIXED and APIC_DM_LOWEST instead. Fixes: (fdcf75621375 'KVM: x86: Disable posted interrupts for non-standard IRQs delivery modes') Cc: Alexander Graf <graf@amazon.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Message-Id: <1586239989-58305-1-git-send-email-suravee.suthikulpanit@amd.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Tested-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-01ftrace/x86: Fix trace event registration for syscalls without argumentsKonstantin Khlebnikov1-2/+3
The refactoring of SYSCALL_DEFINE0() macros removed the ABI stubs and simply defines __abi_sys_$NAME as alias of __do_sys_$NAME. As a result kallsyms_lookup() returns "__do_sys_$NAME" which does not match with the declared trace event name. See also commit 1c758a2202a6 ("tracing/x86: Update syscall trace events to handle new prefixed syscall func names"). Add __do_sys_ to the valid prefixes which are checked in arch_syscall_match_sym_name(). Fixes: d2b5de495ee9 ("x86/entry: Refactor SYSCALL_DEFINE0 macros") Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lkml.kernel.org/r/158636958997.7900.16485049455470033557.stgit@buzz
2020-04-27Merge tag 'hyperv-fixes-signed' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull Hyper-V fixes from Wei Liu: - Two patches from Dexuan fixing suspension bugs - Three cleanup patches from Andy and Michael * tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: hyper-v: Remove internal types from UAPI header hyper-v: Use UUID API for exporting the GUID x86/hyperv: Suspend/resume the VP assist page for hibernation Drivers: hv: Move AEOI determination to architecture dependent code Drivers: hv: vmbus: Fix Suspend-to-Idle for Generation-2 VM
2020-04-25x86/unwind/orc: Fix premature unwind stoppage due to IRET framesJosh Poimboeuf1-1/+1
The following execution path is possible: fsnotify() [ realign the stack and store previous SP in R10 ] <IRQ> [ only IRET regs saved ] common_interrupt() interrupt_entry() <NMI> [ full pt_regs saved ] ... [ unwind stack ] When the unwinder goes through the NMI and the IRQ on the stack, and then sees fsnotify(), it doesn't have access to the value of R10, because it only has the five IRET registers. So the unwind stops prematurely. However, because the interrupt_entry() code is careful not to clobber R10 before saving the full regs, the unwinder should be able to read R10 from the previously saved full pt_regs associated with the NMI. Handle this case properly. When encountering an IRET regs frame immediately after a full pt_regs frame, use the pt_regs as a backup which can be used to get the C register values. Also, note that a call frame resets the 'prev_regs' value, because a function is free to clobber the registers. For this fix to work, the IRET and full regs frames must be adjacent, with no FUNC frames in between. So replace the FUNC hint in interrupt_entry() with an IRET_REGS hint. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Jones <dsj@fb.com> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lore.kernel.org/r/97a408167cc09f1cfa0de31a7b70dd88868d743f.1587808742.git.jpoimboe@redhat.com
2020-04-24Merge tag 'kbuild-fixes-v5.7' of ↵Linus Torvalds2-60/+68
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - fix scripts/config to properly handle ':' in string type CONFIG options - fix unneeded rebuilds of DT schema check rule - git rid of ordering dependency between <linux/vermagic.h> and <linux/module.h> to fix build errors in some network drivers - clean up generated headers of host arch with 'make ARCH=um mrproper' * tag 'kbuild-fixes-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: h8300: ignore vmlinux.lds Documentation: kbuild: fix the section title format um: ensure `make ARCH=um mrproper` removes arch/$(SUBARCH)/include/generated/ arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h> kbuild: fix DT binding schema rule again to avoid needless rebuilds scripts/config: allow colons in option strings for sed
2020-04-23arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>Masahiro Yamada2-60/+68
As the bug report [1] pointed out, <linux/vermagic.h> must be included after <linux/module.h>. I believe we should not impose any include order restriction. We often sort include directives alphabetically, but it is just coding style convention. Technically, we can include header files in any order by making every header self-contained. Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in <asm/module.h>, which is not included from <linux/vermagic.h>. Hence, the straight-forward fix-up would be as follows: |--- a/include/linux/vermagic.h |+++ b/include/linux/vermagic.h |@@ -1,5 +1,6 @@ | /* SPDX-License-Identifier: GPL-2.0 */ | #include <generated/utsrelease.h> |+#include <linux/module.h> | | /* Simply sanity version stamp for modules. */ | #ifdef CONFIG_SMP This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC definitions into <asm/vermagic.h>. With this, <linux/module.h> and <linux/vermagic.h> will be orthogonal, and the location of MODULE_ARCH_VERMAGIC definitions will be consistent. For arc and ia64, MODULE_PROC_FAMILY is only used for defining MODULE_ARCH_VERMAGIC. I squashed it. For hexagon, nds32, and xtensa, I removed <asm/modules.h> entirely because they contained nothing but MODULE_ARCH_VERMAGIC definition. Kbuild will automatically generate <asm/modules.h> at build-time, wrapping <asm-generic/module.h>. [1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic Reported-by: Borislav Petkov <bp@suse.de> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Jessica Yu <jeyu@kernel.org>
2020-04-21Merge tag 'kvm-s390-master-5.7-2' of ↵Paolo Bonzini12-62/+151
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-master KVM: s390: Fix for 5.7 and maintainer update - Silence false positive lockdep warning - add Claudio as reviewer
2020-04-21Drivers: hv: Move AEOI determination to architecture dependent codeMichael Kelley1-0/+2
Hyper-V on ARM64 doesn't provide a flag for the AEOI recommendation in ms_hyperv.hints, so having the test in architecture independent code doesn't work. Resolve this by moving the check of the flag to an architecture dependent helper function. No functionality is changed. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20200420164926.24471-1-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-04-19Merge tag 'x86-urgent-2020-04-19' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 and objtool fixes from Thomas Gleixner: "A set of fixes for x86 and objtool: objtool: - Ignore the double UD2 which is emitted in BUG() when CONFIG_UBSAN_TRAP is enabled. - Support clang non-section symbols in objtool ORC dump - Fix switch table detection in .text.unlikely - Make the BP scratch register warning more robust. x86: - Increase microcode maximum patch size for AMD to cope with new CPUs which have a larger patch size. - Fix a crash in the resource control filesystem when the removal of the default resource group is attempted. - Preserve Code and Data Prioritization enabled state accross CPU hotplug. - Update split lock cpu matching to use the new X86_MATCH macros. - Change the split lock enumeration as Intel finaly decided that the IA32_CORE_CAPABILITIES bits are not architectural contrary to what the SDM claims. !@#%$^! - Add Tremont CPU models to the split lock detection cpu match. - Add a missing static attribute to make sparse happy" * tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Add Tremont family CPU models x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural x86/resctrl: Preserve CDP enable over CPU hotplug x86/resctrl: Fix invalid attempt at removing the default resource group x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL() x86/umip: Make umip_insns static x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE objtool: Make BP scratch register warning more robust objtool: Fix switch table detection in .text.unlikely objtool: Support Clang non-section symbols in ORC generation objtool: Support Clang non-section symbols in ORC dump objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
2020-04-14x86/microcode/AMD: Increase microcode PATCH_MAX_SIZEJohn Allen1-1/+1
Future AMD CPUs will have microcode patches that exceed the default 4K patch size. Raise our limit. Signed-off-by: John Allen <john.allen@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org # v4.14.. Link: https://lkml.kernel.org/r/20200409152931.GA685273@mojo.amd.com
2020-04-14KVM: SVM: move more vmentry code to assemblyPaolo Bonzini1-21/+0
Manipulate IF around vmload/vmsave to remove the confusing usage of local_irq_enable where interrupts are actually disabled via GIF. And stuff the RSB immediately without waiting for a RET to avoid Spectre-v2 attacks. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-14efi/x86: Revert struct layout change to fix kexec boot regressionArd Biesheuvel1-0/+2
Commit 0a67361dcdaa29 ("efi/x86: Remove runtime table address from kexec EFI setup data") removed the code that retrieves the non-remapped UEFI runtime services pointer from the data structure provided by kexec, as it was never really needed on the kexec boot path: mapping the runtime services table at its non-remapped address is only needed when calling SetVirtualAddressMap(), which never happens during a kexec boot in the first place. However, dropping the 'runtime' member from struct efi_setup_data was a mistake. That struct is shared ABI between the kernel and the kexec tooling for x86, and so we cannot simply change its layout. So let's put back the removed field, but call it 'unused' to reflect the fact that we never look at its contents. While at it, add a comment to remind our future selves that the layout is external ABI. Fixes: 0a67361dcdaa29 ("efi/x86: Remove runtime table address from kexec EFI setup data") Reported-by: Theodore Ts'o <tytso@mit.edu> Tested-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Dave Young <dyoung@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-12Merge tag 'x86-urgent-2020-04-12' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of three patches to fix the fallout of the newly added split lock detection feature. It addressed the case where a KVM guest triggers a split lock #AC and KVM reinjects it into the guest which is not prepared to handle it. Add proper sanity checks which prevent the unconditional injection into the guest and handles the #AC on the host side in the same way as user space detections are handled. Depending on the detection mode it either warns and disables detection for the task or kills the task if the mode is set to fatal" * tag 'x86-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM: VMX: Extend VMXs #AC interceptor to handle split lock #AC in guest KVM: x86: Emulate split-lock access as a write in emulator x86/split_lock: Provide handle_guest_split_lock()
2020-04-11Merge tag 'kbuild-v5.7-2' of ↵Linus Torvalds2-53/+0
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - raise minimum supported binutils version to 2.23 - remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports - move remaining CONFIG_AS_* tests to Kconfig from Makefile - enable -Wtautological-compare warnings to catch more issues - do not support GCC plugins for GCC <= 4.7 - fix various breakages of 'make xconfig' - include the linker version used for linking the kernel into LINUX_COMPILER, which is used for the banner, and also exposed to /proc/version - link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y, which allows us to remove the lib-ksyms.o workaround, and to solve the last known issue of the LLVM linker - add dummy tools in scripts/dummy-tools/ to enable all compiler tests in Kconfig, which will be useful for distro maintainers - support the single switch, LLVM=1 to use Clang and all LLVM utilities instead of GCC and Binutils. - support LLVM_IAS=1 to enable the integrated assembler, which is still experimental * tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (36 commits) kbuild: fix comment about missing include guard detection kbuild: support LLVM=1 to switch the default tools to Clang/LLVM kbuild: replace AS=clang with LLVM_IAS=1 kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y MIPS: fw: arc: add __weak to prom_meminit and prom_free_prom_memory kbuild: remove -I$(srctree)/tools/include from scripts/Makefile kbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h Documentation/llvm: fix the name of llvm-size kbuild: mkcompile_h: Include $LD version in /proc/version kconfig: qconf: Fix a few alignment issues kconfig: qconf: remove some old bogus TODOs kconfig: qconf: fix support for the split view mode kconfig: qconf: fix the content of the main widget kconfig: qconf: Change title for the item window kconfig: qconf: clean deprecated warnings gcc-plugins: drop support for GCC <= 4.7 kbuild: Enable -Wtautological-compare x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2 crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean' ...
2020-04-11x86/split_lock: Provide handle_guest_split_lock()Thomas Gleixner1-0/+6
Without at least minimal handling for split lock detection induced #AC, VMX will just run into the same problem as the VMWare hypervisor, which was reported by Kenneth. It will inject the #AC blindly into the guest whether the guest is prepared or not. Provide a function for guest mode which acts depending on the host SLD mode. If mode == sld_warn, treat it like user space, i.e. emit a warning, disable SLD and mark the task accordingly. Otherwise force SIGBUS. [ bp: Add a !CPU_SUP_INTEL stub for handle_guest_split_lock(). ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lkml.kernel.org/r/20200410115516.978037132@linutronix.de Link: https://lkml.kernel.org/r/20200402123258.895628824@linutronix.de
2020-04-11x86/mm: introduce __set_memory_prot()Logan Gunthorpe1-0/+1
For use in the 32bit arch_add_memory() to set the pgprot type of the memory to add. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Hildenbrand <david@redhat.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-5-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-11x86/mm: thread pgprot_t through init_memory_mapping()Logan Gunthorpe2-3/+3
In preparation to support a pgprot_t argument for arch_add_memory(). It's required to move the prototype of init_memory_mapping() seeing the original location came before the definition of pgprot_t. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Hildenbrand <david@redhat.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-4-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-11mm/vma: define a default value for VM_DATA_DEFAULT_FLAGSAnshuman Khandual1-3/+1
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the existing VM_STACK_DEFAULT_FLAGS. While here, also define some more macros with standard VMA access flag combinations that are used frequently across many platforms. Apart from simplification, this reduces code duplication as well. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Guo Ren <guoren@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Brian Cain <bcain@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paulburton@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Rich Felker <dalias@libc.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Chris Zankel <chris@zankel.net> Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-11mm: define pte_index as macro for x86Arjun Roy1-0/+3
pte_index() is either defined as a macro (e.g. sparc64) or as an inlined function (e.g. x86). vm_insert_pages() depends on pte_index but it is not defined on all platforms (e.g. m68k). To fix compilation of vm_insert_pages() on architectures not providing pte_index(), we perform the following fix: 0. For platforms where it is meaningful, and defined as a macro, no change is needed. 1. For platforms where it is meaningful and defined as an inlined function, and we want to use it with vm_insert_pages(), we define a degenerate macro of the form: #define pte_index pte_index 2. vm_insert_pages() checks for the existence of a pte_index macro definition. If found, it implements a batched insert. If not found, it devolves to calling vm_insert_page() in a loop. This patch implements step 1 for x86. v3 of this patch fixes a compilation warning for an unused method. v2 of this patch moved a macro definition to a more readable location. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Matthew Wilcox <willy@infradead.org> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200228054714.204424-1-arjunroy.kdev@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-08x86: remove always-defined CONFIG_AS_AVXMasahiro Yamada1-9/+0
CONFIG_AS_AVX was introduced by commit ea4d26ae24e5 ("raid5: add AVX optimized RAID5 checksumming"). We raise the minimal supported binutils version from time to time. The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum required binutils version to 2.21"). I confirmed the code in $(call as-instr,...) can be assembled by the binutils 2.21 assembler and also by LLVM integrated assembler. Remove CONFIG_AS_AVX, which is always defined. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Ingo Molnar <mingo@kernel.org>
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