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2019-04-02x86/speculation/mds: Add mds=full,nosmt cmdline optionJosh Poimboeuf
Add the mds=full,nosmt cmdline option. This is like mds=full, but with SMT disabled if the CPU is vulnerable. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Acked-by: Jiri Kosina <jkosina@suse.cz>
2019-04-01x86/resctrl: Fix typos in the mba_sc mount optionXiaochen Shen
The user can control the MBA memory bandwidth in MBps (Mega Bytes per second) units of the MBA Software Controller (mba_sc) by using the "mba_MBps" mount option. For details, see Documentation/x86/resctrl_ui.txt. However, commit 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context") changed the mount option name from "mba_MBps" to "mba_mpbs" by mistake. Change it back from to "mba_MBps" because it is user-visible, and correct "Opt_mba_mpbs" spelling to "Opt_mba_mbps". [ bp: massage commit message. ] Fixes: 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context") Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: dhowells@redhat.com Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: pei.p.jia@intel.com Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1553896238-22130-1-git-send-email-xiaochen.shen@intel.com
2019-03-29x86/mce: Remove mce_report_event()Borislav Petkov
Calling this function has been wrong for a while now: * Can't call schedule_work() in #MC context. * mce_notify_irq() either. * None of that noodling is needed anymore - all it needs to do is kick the IRQ work which would self-IPI so that once the #MC handler is done, the work queue will run and process queued MCE records. So remove it. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86@kernel.org Link: https://lkml.kernel.org/r/20190325172121.7926-1-bp@alien8.de
2019-03-27x86/mce: Handle varying MCA bank countsYazen Ghannam
Linux reads MCG_CAP[Count] to find the number of MCA banks visible to a CPU. Currently, this number is the same for all CPUs and a warning is shown if there is a difference. The number of banks is overwritten with the MCG_CAP[Count] value of each following CPU that boots. According to the Intel SDM and AMD APM, the MCG_CAP[Count] value gives the number of banks that are available to a "processor implementation". The AMD BKDGs/PPRs further clarify that this value is per core. This value has historically been the same for every core in the system, but that is not an architectural requirement. Future AMD systems may have different MCG_CAP[Count] values per core, so the assumption that all CPUs will have the same MCG_CAP[Count] value will no longer be valid. Also, the first CPU to boot will allocate the struct mce_banks[] array using the number of banks based on its MCG_CAP[Count] value. The machine check handler and other functions use the global number of banks to iterate and index into the mce_banks[] array. So it's possible to use an out-of-bounds index on an asymmetric system where a following CPU sees a MCG_CAP[Count] value greater than its predecessors. Thus, allocate the mce_banks[] array to the maximum number of banks. This will avoid the potential out-of-bounds index since the value of mca_cfg.banks is capped to MAX_NR_BANKS. Set the value of mca_cfg.banks equal to the max of the previous value and the value for the current CPU. This way mca_cfg.banks will always represent the max number of banks detected on any CPU in the system. This will ensure that all CPUs will access all the banks that are visible to them. A CPU that can access fewer than the max number of banks will find the registers of the extra banks to be read-as-zero. Furthermore, print the resulting number of MCA banks in use. Do this in mcheck_late_init() so that the final value is printed after all CPUs have been initialized. Finally, get bank count from target CPU when doing injection with mce-inject module. [ bp: Remove out-of-bounds example, passify and cleanup commit message. ] Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20180727214009.78289-1-Yazen.Ghannam@amd.com
2019-03-27x86/mce: Fix machine_check_poll() tests for error typesTony Luck
There has been a lurking "TBD" in the machine check poll routine ever since it was first split out from the machine check handler. The potential issue is that the poll routine may have just begun a read from the STATUS register in a machine check bank when the hardware logs an error in that bank and signals a machine check. That race used to be pretty small back when machine checks were broadcast, but the addition of local machine check means that the poll code could continue running and clear the error from the bank before the local machine check handler on another CPU gets around to reading it. Fix the code to be sure to only process errors that need to be processed in the poll code, leaving other logged errors alone for the machine check handler to find and process. [ bp: Massage a bit and flip the "== 0" check to the usual !(..) test. ] Fixes: b79109c3bbcf ("x86, mce: separate correct machine check poller and fatal exception handler") Fixes: ed7290d0ee8f ("x86, mce: implement new status bits") Reported-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: Yazen Ghannam <Yazen.Ghannam@amd.com> Link: https://lkml.kernel.org/r/20190312170938.GA23035@agluck-desk
2019-03-24x86/resctrl: Remove unused variablePeng Hao
Variable "struct rdt_resource *r" is set but not used. So remove it. Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1552152584-26087-1-git-send-email-peng.hao2@zte.com.cn
2019-03-23x86/CPU/hygon: Fix phys_proc_id calculation logic for multi-die processorsPu Wen
The Hygon family 18h multi-die processor platform supports 1, 2 or 4-Dies per socket. The topology looks like this: System View (with 1-Die 2-Socket): |------------| ------ ----- SOCKET0 | D0 | | D1 | SOCKET1 ------ ----- System View (with 2-Die 2-socket): -------------------- | -------------|------ | | | | ------------ ------------ SOCKET0 | D1 -- D0 | | D3 -- D2 | SOCKET1 ------------ ------------ System View (with 4-Die 2-Socket) : -------------------- | -------------|------ | | | | ------------ ------------ | D1 -- D0 | | D7 -- D6 | | | \/ | | | | \/ | | SOCKET0 | | /\ | | | | /\ | | SOCKET1 | D2 -- D3 | | D4 -- D5 | ------------ ------------ | | | | ------|------------| | -------------------- Currently phys_proc_id = initial_apicid >> bits calculates the physical processor ID from the initial_apicid by shifting *bits*. However, this does not work for 1-Die and 2-Die 2-socket systems. According to document [1] section 2.1.11.1, the bits is the value of CPUID_Fn80000008_ECX[12:15]. The possible values are 4, 5 or 6 which mean: 4 - 1 die 5 - 2 dies 6 - 3/4 dies. Hygon programs the initial ApicId the same way as AMD. The ApicId is read from CPUID_Fn00000001_EBX (see section 2.1.11.1 of referrence [1]) and the definition is as below (see section 2.1.10.2.1.3 of [1]): ------------------------------------------------- Bit | 6 | 5 4 | 3 | 2 1 0 | |-----------|---------|--------|----------------| IDs | Socket ID | Node ID | CCX ID | Core/Thread ID | ------------------------------------------------- So for 3/4-Die configurations, the bits variable is 6, which is the same as the ApicID definition field. For 1-Die and 2-Die configurations, bits is 4 or 5, which will cause the right shifted result to not be exactly the value of socket ID. However, the socket ID should be obtained from ApicId[6]. To fix the problem and match the ApicID field definition, set the shift bits to 6 for all Hygon family 18h multi-die CPUs. Because AMD doesn't have 2-Socket systems with 1-Die/2-Die processors (see reference [2]), this doesn't need to be changed on the AMD side but only for Hygon. References: [1] https://www.amd.com/system/files/TechDocs/54945_PPR_Family_17h_Models_00h-0Fh.pdf [2] https://www.amd.com/en/products/specifications/processors [bp: heavily massage commit message. ] Signed-off-by: Pu Wen <puwen@hygon.cn> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Lendacky <Thomas.Lendacky@amd.com> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1553355740-19999-1-git-send-email-puwen@hygon.cn
2019-03-21x86/cpu/cyrix: Use correct macros for Cyrix calls on Geode processorsMatthew Whitehead
There are comments in processor-cyrix.h advising you to _not_ make calls using the deprecated macros in this style: setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80); This is because it expands the macro into a non-functioning calling sequence. The calling order must be: outb(CX86_CCR2, 0x22); inb(0x23); From the comments: * When using the old macros a line like * setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88); * gets expanded to: * do { * outb((CX86_CCR2), 0x22); * outb((({ * outb((CX86_CCR2), 0x22); * inb(0x23); * }) | 0x88), 0x23); * } while (0); The new macros fix this problem, so use them instead. Tested on an actual Geode processor. Signed-off-by: Matthew Whitehead <tedheadster@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: luto@kernel.org Link: https://lkml.kernel.org/r/1552596361-8967-2-git-send-email-tedheadster@gmail.com
2019-03-21x86/microcode: Announce reload operation's completionBorislav Petkov
By popular demand, issue a single line to dmesg after the reload operation completes to let the user know that a reload has at least been attempted. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190313110022.8229-1-bp@alien8.de
2019-03-12Merge branch 'work.mount' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs mount infrastructure updates from Al Viro: "The rest of core infrastructure; no new syscalls in that pile, but the old parts are switched to new infrastructure. At that point conversions of individual filesystems can happen independently; some are done here (afs, cgroup, procfs, etc.), there's also a large series outside of that pile dealing with NFS (quite a bit of option-parsing stuff is getting used there - it's one of the most convoluted filesystems in terms of mount-related logics), but NFS bits are the next cycle fodder. It got seriously simplified since the last cycle; documentation is probably the weakest bit at the moment - I considered dropping the commit introducing Documentation/filesystems/mount_api.txt (cutting the size increase by quarter ;-), but decided that it would be better to fix it up after -rc1 instead. That pile allows to do followup work in independent branches, which should make life much easier for the next cycle. fs/super.c size increase is unpleasant; there's a followup series that allows to shrink it considerably, but I decided to leave that until the next cycle" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits) afs: Use fs_context to pass parameters over automount afs: Add fs_context support vfs: Add some logging to the core users of the fs_context log vfs: Implement logging through fs_context vfs: Provide documentation for new mount API vfs: Remove kern_mount_data() hugetlbfs: Convert to fs_context cpuset: Use fs_context kernfs, sysfs, cgroup, intel_rdt: Support fs_context cgroup: store a reference to cgroup_ns into cgroup_fs_context cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper cgroup_do_mount(): massage calling conventions cgroup: stash cgroup_root reference into cgroup_fs_context cgroup2: switch to option-by-option parsing cgroup1: switch to option-by-option parsing cgroup: take options parsing into ->parse_monolithic() cgroup: fold cgroup1_mount() into cgroup1_get_tree() cgroup: start switching to fs_context ipc: Convert mqueue fs to fs_context proc: Add fs_context support to procfs ...
2019-03-10Merge tag 'iommu-updates-v5.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: - A big cleanup and optimization patch-set for the Tegra GART driver - Documentation updates and fixes for the IOMMU-API - Support for page request in Intel VT-d scalable mode - Intel VT-d dma_[un]map_resource() support - Updates to the ATS enabling code for PCI (acked by Bjorn) and Intel VT-d to align with the latest version of the ATS spec - Relaxed IRQ source checking in the Intel VT-d driver for some aliased devices, needed for future devices which send IRQ messages from more than on request-ID - IRQ remapping driver for Hyper-V - Patches to make generic IOVA and IO-Page-Table code usable outside of the IOMMU code - Various other small fixes and cleanups * tag 'iommu-updates-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (60 commits) iommu/vt-d: Get domain ID before clear pasid entry iommu/vt-d: Fix NULL pointer reference in intel_svm_bind_mm() iommu/vt-d: Set context field after value initialized iommu/vt-d: Disable ATS support on untrusted devices iommu/mediatek: Fix semicolon code style issue MAINTAINERS: Add Hyper-V IOMMU driver into Hyper-V CORE AND DRIVERS scope iommu/hyper-v: Add Hyper-V stub IOMMU driver x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available PCI/ATS: Add inline to pci_prg_resp_pasid_required() iommu/vt-d: Check identity map for hot-added devices iommu: Fix IOMMU debugfs fallout iommu: Document iommu_ops.is_attach_deferred() iommu: Document iommu_ops.iotlb_sync_map() iommu/vt-d: Enable ATS only if the device uses page aligned address. PCI/ATS: Add pci_ats_page_aligned() interface iommu/vt-d: Fix PRI/PASID dependency issue. PCI/ATS: Add pci_prg_resp_pasid_required() interface. iommu/vt-d: Allow interrupts from the entire bus for aliased devices iommu/vt-d: Add helper to set an IRTE to verify only the bus number iommu: Fix flush_tlb_all typo ...
2019-03-08Merge branch 'ras-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS updates from Borislav Petkov: "This time around we have in store: - Disable MC4_MISC thresholding banks on all AMD family 0x15 models (Shirish S) - AMD MCE error descriptions update and error decode improvements (Yazen Ghannam) - The usual smaller conversions and fixes" * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Improve error message when kernel cannot recover, p2 EDAC/mce_amd: Decode MCA_STATUS in bit definition order EDAC/mce_amd: Decode MCA_STATUS[Scrub] bit EDAC, mce_amd: Print ExtErrorCode and description on a single line EDAC, mce_amd: Match error descriptions to latest documentation x86/MCE/AMD, EDAC/mce_amd: Add new error descriptions for some SMCA bank types x86/MCE/AMD, EDAC/mce_amd: Add new McaTypes for CS, PSP, and SMU units x86/MCE/AMD, EDAC/mce_amd: Add new MP5, NBIO, and PCIE SMCA bank types RAS: Add a MAINTAINERS entry RAS: Use consistent types for UUIDs x86/MCE/AMD: Carve out the MC4_MISC thresholding quirk x86/MCE/AMD: Turn off MC4_MISC thresholding on all family 0x15 models x86/MCE: Switch to use the new generic UUID API
2019-03-07Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Various cleanups and simplifications, none of them really stands out, they are all over the place" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/uaccess: Remove unused __addr_ok() macro x86/smpboot: Remove unused phys_id variable x86/mm/dump_pagetables: Remove the unused prev_pud variable x86/fpu: Move init_xstate_size() to __init section x86/cpu_entry_area: Move percpu_setup_debug_store() to __init section x86/mtrr: Remove unused variable x86/boot/compressed/64: Explain paging_prepare()'s return value x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definition x86/asm/suspend: Drop ENTRY from local data x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery x86/boot: Save several bytes in decompressor x86/trap: Remove useless declaration x86/mm/tlb: Remove unused cpu variable x86/events: Mark expected switch-case fall-throughs x86/asm-prototypes: Remove duplicate include <asm/page.h> x86/kernel: Mark expected switch-case fall-throughs x86/insn-eval: Mark expected switch-case fall-through x86/platform/UV: Replace kmalloc() and memset() with k[cz]alloc() calls x86/e820: Replace kmalloc() + memcpy() with kmemdup()
2019-03-06Documentation: Move L1TF to separate directoryThomas Gleixner
Move L!TF to a separate directory so the MDS stuff can be added at the side. Otherwise the all hardware vulnerabilites have their own top level entry. Should have done that right away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Add mitigation mode VMWERVThomas Gleixner
In virtualized environments it can happen that the host has the microcode update which utilizes the VERW instruction to clear CPU buffers, but the hypervisor is not yet updated to expose the X86_FEATURE_MD_CLEAR CPUID bit to guests. Introduce an internal mitigation mode VMWERV which enables the invocation of the CPU buffer clearing even if X86_FEATURE_MD_CLEAR is not set. If the system has no updated microcode this results in a pointless execution of the VERW instruction wasting a few CPU cycles. If the microcode is updated, but not exposed to a guest then the CPU buffers will be cleared. That said: Virtual Machines Will Eventually Receive Vaccine Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Add sysfs reporting for MDSThomas Gleixner
Add the sysfs reporting file for MDS. It exposes the vulnerability and mitigation state similar to the existing files for the other speculative hardware vulnerabilities. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Add mitigation control for MDSThomas Gleixner
Now that the mitigations are in place, add a command line parameter to control the mitigation, a mitigation selector function and a SMT update mechanism. This is the minimal straight forward initial implementation which just provides an always on/off mode. The command line parameter is: mds=[full|off] This is consistent with the existing mitigations for other speculative hardware vulnerabilities. The idle invocation is dynamically updated according to the SMT state of the system similar to the dynamic update of the STIBP mitigation. The idle mitigation is limited to CPUs which are only affected by MSBDS and not any other variant, because the other variants cannot be mitigated on SMT enabled systems. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Conditionally clear CPU buffers on idle entryThomas Gleixner
Add a static key which controls the invocation of the CPU buffer clear mechanism on idle entry. This is independent of other MDS mitigations because the idle entry invocation to mitigate the potential leakage due to store buffer repartitioning is only necessary on SMT systems. Add the actual invocations to the different halt/mwait variants which covers all usage sites. mwaitx is not patched as it's not available on Intel CPUs. The buffer clear is only invoked before entering the C-State to prevent that stale data from the idling CPU is spilled to the Hyper-Thread sibling after the Store buffer got repartitioned and all entries are available to the non idle sibling. When coming out of idle the store buffer is partitioned again so each sibling has half of it available. Now CPU which returned from idle could be speculatively exposed to contents of the sibling, but the buffers are flushed either on exit to user space or on VMENTER. When later on conditional buffer clearing is implemented on top of this, then there is no action required either because before returning to user space the context switch will set the condition flag which causes a flush on the return to user path. Note, that the buffer clearing on idle is only sensible on CPUs which are solely affected by MSBDS and not any other variant of MDS because the other MDS variants cannot be mitigated when SMT is enabled, so the buffer clearing on idle would be a window dressing exercise. This intentionally does not handle the case in the acpi/processor_idle driver which uses the legacy IO port interface for C-State transitions for two reasons: - The acpi/processor_idle driver was replaced by the intel_idle driver almost a decade ago. Anything Nehalem upwards supports it and defaults to that new driver. - The legacy IO port interface is likely to be used on older and therefore unaffected CPUs or on systems which do not receive microcode updates anymore, so there is no point in adding that. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/kvm/vmx: Add MDS protection when L1D Flush is not activeThomas Gleixner
CPUs which are affected by L1TF and MDS mitigate MDS with the L1D Flush on VMENTER when updated microcode is installed. If a CPU is not affected by L1TF or if the L1D Flush is not in use, then MDS mitigation needs to be invoked explicitly. For these cases, follow the host mitigation state and invoke the MDS mitigation before VMENTER. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Clear CPU buffers on exit to userThomas Gleixner
Add a static key which controls the invocation of the CPU buffer clear mechanism on exit to user space and add the call into prepare_exit_to_usermode() and do_nmi() right before actually returning. Add documentation which kernel to user space transition this covers and explain why some corner cases are not mitigated. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Add BUG_MSBDS_ONLYThomas Gleixner
This bug bit is set on CPUs which are only affected by Microarchitectural Store Buffer Data Sampling (MSBDS) and not by any other MDS variant. This is important because the Store Buffers are partitioned between Hyper-Threads so cross thread forwarding is not possible. But if a thread enters or exits a sleep state the store buffer is repartitioned which can expose data from one thread to the other. This transition can be mitigated. That means that for CPUs which are only affected by MSBDS SMT can be enabled, if the CPU is not affected by other SMT sensitive vulnerabilities, e.g. L1TF. The XEON PHI variants fall into that category. Also the Silvermont/Airmont ATOMs, but for them it's not really relevant as they do not support SMT, but mark them for completeness sake. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation/mds: Add basic bug infrastructure for MDSAndi Kleen
Microarchitectural Data Sampling (MDS), is a class of side channel attacks on internal buffers in Intel CPUs. The variants are: - Microarchitectural Store Buffer Data Sampling (MSBDS) (CVE-2018-12126) - Microarchitectural Fill Buffer Data Sampling (MFBDS) (CVE-2018-12130) - Microarchitectural Load Port Data Sampling (MLPDS) (CVE-2018-12127) MSBDS leaks Store Buffer Entries which can be speculatively forwarded to a dependent load (store-to-load forwarding) as an optimization. The forward can also happen to a faulting or assisting load operation for a different memory address, which can be exploited under certain conditions. Store buffers are partitioned between Hyper-Threads so cross thread forwarding is not possible. But if a thread enters or exits a sleep state the store buffer is repartitioned which can expose data from one thread to the other. MFBDS leaks Fill Buffer Entries. Fill buffers are used internally to manage L1 miss situations and to hold data which is returned or sent in response to a memory or I/O operation. Fill buffers can forward data to a load operation and also write data to the cache. When the fill buffer is deallocated it can retain the stale data of the preceding operations which can then be forwarded to a faulting or assisting load operation, which can be exploited under certain conditions. Fill buffers are shared between Hyper-Threads so cross thread leakage is possible. MLDPS leaks Load Port Data. Load ports are used to perform load operations from memory or I/O. The received data is then forwarded to the register file or a subsequent operation. In some implementations the Load Port can contain stale data from a previous operation which can be forwarded to faulting or assisting loads under certain conditions, which again can be exploited eventually. Load ports are shared between Hyper-Threads so cross thread leakage is possible. All variants have the same mitigation for single CPU thread case (SMT off), so the kernel can treat them as one MDS issue. Add the basic infrastructure to detect if the current CPU is affected by MDS. [ tglx: Rewrote changelog ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06x86/speculation: Consolidate CPU whitelistsThomas Gleixner
The CPU vulnerability whitelists have some overlap and there are more whitelists coming along. Use the driver_data field in the x86_cpu_id struct to denote the whitelisted vulnerabilities and combine all whitelists into one. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Lots of tooling updates - too many to list, here's a few highlights: - Various subcommand updates to 'perf trace', 'perf report', 'perf record', 'perf annotate', 'perf script', 'perf test', etc. - CPU and NUMA topology and affinity handling improvements, - HW tracing and HW support updates: - Intel PT updates - ARM CoreSight updates - vendor HW event updates - BPF updates - Tons of infrastructure updates, both on the build system and the library support side - Documentation updates. - ... and lots of other changes, see the changelog for details. Kernel side updates: - Tighten up kprobes blacklist handling, reduce the number of places where developers can install a kprobe and hang/crash the system. - Fix/enhance vma address filter handling. - Various PMU driver updates, small fixes and additions. - refcount_t conversions - BPF updates - error code propagation enhancements - misc other changes" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (238 commits) perf script python: Add Python3 support to syscall-counts-by-pid.py perf script python: Add Python3 support to syscall-counts.py perf script python: Add Python3 support to stat-cpi.py perf script python: Add Python3 support to stackcollapse.py perf script python: Add Python3 support to sctop.py perf script python: Add Python3 support to powerpc-hcalls.py perf script python: Add Python3 support to net_dropmonitor.py perf script python: Add Python3 support to mem-phys-addr.py perf script python: Add Python3 support to failed-syscalls-by-pid.py perf script python: Add Python3 support to netdev-times.py perf tools: Add perf_exe() helper to find perf binary perf script: Handle missing fields with -F +.. perf data: Add perf_data__open_dir_data function perf data: Add perf_data__(create_dir|close_dir) functions perf data: Fail check_backup in case of error perf data: Make check_backup work over directories perf tools: Add rm_rf_perf_data function perf tools: Add pattern name checking to rm_rf perf tools: Add depth checking to rm_rf perf data: Add global path holder ...
2019-03-05Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/pti update from Thomas Gleixner: "Just a single change from the anti-performance departement: - Add a new PR_SPEC_DISABLE_NOEXEC option which allows to apply the speculation protections on a process without inheriting the state on exec. This remedies a situation where a Java-launcher has speculation protections enabled because that's the default for JVMs which causes the launched regular harmless processes to inherit the protection state which results in unintended performance degradation" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation: Add PR_SPEC_DISABLE_NOEXEC
2019-02-28x86/Hyper-V: Set x2apic destination mode to physical when x2apic is availableLan Tianyu
Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic, set x2apic destination mode to physcial mode when x2apic is available and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have 8-bit APIC id. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-02-28kernfs, sysfs, cgroup, intel_rdt: Support fs_contextDavid Howells
Make kernfs support superblock creation/mount/remount with fs_context. This requires that sysfs, cgroup and intel_rdt, which are built on kernfs, be made to support fs_context also. Notes: (1) A kernfs_fs_context struct is created to wrap fs_context and the kernfs mount parameters are moved in here (or are in fs_context). (2) kernfs_mount{,_ns}() are made into kernfs_get_tree(). The extra namespace tag parameter is passed in the context if desired (3) kernfs_free_fs_context() is provided as a destructor for the kernfs_fs_context struct, but for the moment it does nothing except get called in the right places. (4) sysfs doesn't wrap kernfs_fs_context since it has no parameters to pass, but possibly this should be done anyway in case someone wants to add a parameter in future. (5) A cgroup_fs_context struct is created to wrap kernfs_fs_context and the cgroup v1 and v2 mount parameters are all moved there. (6) cgroup1 parameter parsing error messages are now handled by invalf(), which allows userspace to collect them directly. (7) cgroup1 parameter cleanup is now done in the context destructor rather than in the mount/get_tree and remount functions. Weirdies: (*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held, but then uses the resulting pointer after dropping the locks. I'm told this is okay and needs commenting. (*) The cgroup refcount web. This really needs documenting. (*) cgroup2 only has one root? Add a suggestion from Thomas Gleixner in which the RDT enablement code is placed into its own function. [folded a leak fix from Andrey Vagin] Signed-off-by: David Howells <dhowells@redhat.com> cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> cc: Tejun Heo <tj@kernel.org> cc: Li Zefan <lizefan@huawei.com> cc: Johannes Weiner <hannes@cmpxchg.org> cc: cgroups@vger.kernel.org cc: fenghua.yu@intel.com Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-28Merge branch 'linus' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-25x86/mce: Improve error message when kernel cannot recover, p2Tony Luck
In c7d606f560e4 ("x86/mce: Improve error message when kernel cannot recover") a case was added for a machine check caused by a DATA access to poison memory from the kernel. A case should have been added also for an uncorrectable error during an instruction fetch in the kernel. Add that extra case so the error message now reads: mce: [Hardware Error]: Machine check: Instruction fetch error in kernel Fixes: c7d606f560e4 ("x86/mce: Improve error message when kernel cannot recover") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Pu Wen <puwen@hygon.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190225205940.15226-1-tony.luck@intel.com
2019-02-11Merge branch 'x86/cpu' into perf/core, to pick up dependent commitIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-11x86/cpufeature: Add facility to check for min microcode revisionsKan Liang
For bug workarounds or checks, it is useful to check for specific microcode revisions. Add a new generic function to match the CPU with stepping. Add the other function to check the min microcode revisions for the matched CPU. A new table format is introduced to facilitate the quirk to fill the related information. This does not change the existing x86_cpu_id because it's an ABI shared with modules, and also has quite different requirements, as in no wildcards, but everything has to be matched exactly. Originally-by: Andi Kleen <ak@linux.intel.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: eranian@google.com Link: https://lkml.kernel.org/r/1549319013-4522-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-10Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "A handful of fixes: - Fix an MCE corner case bug/crash found via MCE injection testing - Fix 5-level paging boot crash - Fix MCE recovery cache invalidation bug - Fix regression on Xen guests caused by a recent PMD level mremap speedup optimization" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Make set_pmd_at() paravirt aware x86/mm/cpa: Fix set_mce_nospec() x86/boot/compressed/64: Do not corrupt EDX on EFER.LME=1 setting x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()
2019-02-08x86/mtrr: Remove unused variableBo Yu
Compiling the kernel with W=1 results in the following warning: arch/x86/kernel/cpu/mtrr/cleanup.c:299:16: warning: variable ‘second_basek’ set but not used [-Wunused-but-set-variable] unsigned long second_basek, second_sizek; Remove the unused variable. [ tglx: Massaged changelog ] Signed-off-by: Bo Yu <tsu.yubo@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: puwen@hygon.cn Link: https://lkml.kernel.org/r/20190208125343.11451-1-tsu.yubo@gmail.com
2019-02-05x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definitionReinette Chatre
The definition of MSR_MISC_FEATURE_CONTROL was first introduced in 98af74599ea0 ("x86 msr_index.h: Define MSR_MISC_FEATURE_CONTROL") and present in Linux since v4.11. The Cache Pseudo-Locking code added this duplicate definition in more recent f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits"), available since v4.19. Remove the duplicate definition from the resctrl subsystem and let that code obtain the needed definition from the core architecture msr-index.h instead. Fixes: f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits") Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: gavin.hindman@intel.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: jithu.joseph@intel.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/ff6b95d9b6ef6f4ac96267f130719ba1af09614b.1549312475.git.reinette.chatre@intel.com
2019-02-03Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A few updates for x86: - Fix an unintended sign extension issue in the fault handling code - Rename the new resource control config switch so it's less confusing - Avoid setting up EFI info in kexec when the EFI runtime is disabled. - Fix the microcode version check in the AMD microcode loader so it only loads higher version numbers and never downgrades - Set EFER.LME in the 32bit trampoline before returning to long mode to handle older AMD/KVM behaviour properly. - Add Darren and Andy as x86/platform reviewers" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Avoid confusion over the new X86_RESCTRL config x86/kexec: Don't setup EFI info if EFI runtime is not enabled x86/microcode/amd: Don't falsely trick the late loading mechanism MAINTAINERS: Add Andy and Darren as arch/x86/platform/ reviewers x86/fault: Fix sign-extend unintended sign extension x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning to long mode x86/cpu: Add Atom Tremont (Jacobsville)
2019-02-03x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()Tony Luck
Internal injection testing crashed with a console log that said: mce: [Hardware Error]: CPU 7: Machine Check Exception: f Bank 0: bd80000000100134 This caused a lot of head scratching because the MCACOD (bits 15:0) of that status is a signature from an L1 data cache error. But Linux says that it found it in "Bank 0", which on this model CPU only reports L1 instruction cache errors. The answer was that Linux doesn't initialize "m->bank" in the case that it finds a fatal error in the mce_no_way_out() pre-scan of banks. If this was a local machine check, then this partially initialized struct mce is being passed to mce_panic(). Fix is simple: just initialize m->bank in the case of a fatal error. Fixes: 40c36e2741d7 ("x86/mce: Fix incorrect "Machine check from unknown source" message") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Cc: stable@vger.kernel.org # v4.18 Note pre-v5.0 arch/x86/kernel/cpu/mce/core.c was called arch/x86/kernel/cpu/mcheck/mce.c Link: https://lkml.kernel.org/r/20190201003341.10638-1-tony.luck@intel.com
2019-02-03x86/MCE/AMD, EDAC/mce_amd: Add new error descriptions for some SMCA bank typesYazen Ghannam
Some SMCA bank types on future systems will report new error types even though the bank type is not treated as a new version. These new error types will reported by bits that are reserved in past systems. Add the new error descriptions to the lists in edac_mce_amd. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Shirish S <Shirish.S@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190201225534.8177-4-Yazen.Ghannam@amd.com
2019-02-03x86/MCE/AMD, EDAC/mce_amd: Add new McaTypes for CS, PSP, and SMU unitsYazen Ghannam
The existing CS, PSP, and SMU SMCA bank types will see new versions (as indicated by their McaTypes) in future SMCA systems. Add the new (HWID, MCATYPE) tuples for these new versions. Reuse the same names as the older versions, since they are logically the same to the user. SMCA systems won't mix and match IP blocks with different McaType versions in the same system, so there isn't a need to distinguish them. The MCA_IPID register is saved when logging an MCA error, and that can be used to triage the error. Also, add the new error descriptions to edac_mce_amd. Some error types (positions in the list) are overloaded compared to the previous McaTypes. Therefore, just create new lists of the error descriptions to keep things simple even if some of the error descriptions are the same between versions. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Cc: Shirish S <Shirish.S@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190201225534.8177-3-Yazen.Ghannam@amd.com
2019-02-03x86/MCE/AMD, EDAC/mce_amd: Add new MP5, NBIO, and PCIE SMCA bank typesYazen Ghannam
Add the (HWID, MCATYPE) tuples and names for the new MP5, NBIO, and PCIE SMCA bank types. Also, add their respective error descriptions to the MCE decoding module edac_mce_amd. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Cc: Shirish S <Shirish.S@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190201225534.8177-2-Yazen.Ghannam@amd.com
2019-02-02x86/resctrl: Avoid confusion over the new X86_RESCTRL configJohannes Weiner
"Resource Control" is a very broad term for this CPU feature, and a term that is also associated with containers, cgroups etc. This can easily cause confusion. Make the user prompt more specific. Match the config symbol name. [ bp: In the future, the corresponding ARM arch-specific code will be under ARM_CPU_RESCTRL and the arch-agnostic bits will be carved out under the CPU_RESCTRL umbrella symbol. ] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Babu Moger <Babu.Moger@amd.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morse <james.morse@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: linux-doc@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190130195621.GA30653@cmpxchg.org
2019-01-31x86/microcode/amd: Don't falsely trick the late loading mechanismThomas Lendacky
The load_microcode_amd() function searches for microcode patches and attempts to apply a microcode patch if it is of different level than the currently installed level. While the processor won't actually load a level that is less than what is already installed, the logic wrongly returns UCODE_NEW thus signaling to its caller reload_store() that a late loading should be attempted. If the file-system contains an older microcode revision than what is currently running, such a late microcode reload can result in these misleading messages: x86/CPU: CPU features have changed after loading microcode, but might not take effect. x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update. These messages were issued on a system where SME/SEV are not enabled by the BIOS (MSR C001_0010[23] = 0b) because during boot, early_detect_mem_encrypt() is called and cleared the SME and SEV features in this case. However, after the wrong late load attempt, get_cpu_cap() is called and reloads the SME and SEV feature bits, resulting in the messages. Update the microcode level check to not attempt microcode loading if the current level is greater than(!) and not only equal to the current patch level. [ bp: massage commit message. ] Fixes: 2613f36ed965 ("x86/microcode: Attempt late loading only when new microcode is present") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/154894518427.9406.8246222496874202773.stgit@tlendack-t1.amdoffice.net
2019-01-30cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVMJosh Poimboeuf
With the following commit: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") ... the hotplug code attempted to detect when SMT was disabled by BIOS, in which case it reported SMT as permanently disabled. However, that code broke a virt hotplug scenario, where the guest is booted with only primary CPU threads, and a sibling is brought online later. The problem is that there doesn't seem to be a way to reliably distinguish between the HW "SMT disabled by BIOS" case and the virt "sibling not yet brought online" case. So the above-mentioned commit was a bit misguided, as it permanently disabled SMT for both cases, preventing future virt sibling hotplugs. Going back and reviewing the original problems which were attempted to be solved by that commit, when SMT was disabled in BIOS: 1) /sys/devices/system/cpu/smt/control showed "on" instead of "notsupported"; and 2) vmx_vm_init() was incorrectly showing the L1TF_MSG_SMT warning. I'd propose that we instead consider #1 above to not actually be a problem. Because, at least in the virt case, it's possible that SMT wasn't disabled by BIOS and a sibling thread could be brought online later. So it makes sense to just always default the smt control to "on" to allow for that possibility (assuming cpuid indicates that the CPU supports SMT). The real problem is #2, which has a simple fix: change vmx_vm_init() to query the actual current SMT state -- i.e., whether any siblings are currently online -- instead of looking at the SMT "control" sysfs value. So fix it by: a) reverting the original "fix" and its followup fix: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") bc2d8d262cba ("cpu/hotplug: Fix SMT supported evaluation") and b) changing vmx_vm_init() to query the actual current SMT state -- instead of the sysfs control value -- to determine whether the L1TF warning is needed. This also requires the 'sched_smt_present' variable to exported, instead of 'cpu_smt_control'. Fixes: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") Reported-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Joe Mario <jmario@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/e3a85d585da28cc333ecbc1e78ee9216e6da9396.1548794349.git.jpoimboe@redhat.com
2019-01-29x86/speculation: Add PR_SPEC_DISABLE_NOEXECWaiman Long
With the default SPEC_STORE_BYPASS_SECCOMP/SPEC_STORE_BYPASS_PRCTL mode, the TIF_SSBD bit will be inherited when a new task is fork'ed or cloned. It will also remain when a new program is execve'ed. Only certain class of applications (like Java) that can run on behalf of multiple users on a single thread will require disabling speculative store bypass for security purposes. Those applications will call prctl(2) at startup time to disable SSB. They won't rely on the fact the SSB might have been disabled. Other applications that don't need SSBD will just move on without checking if SSBD has been turned on or not. The fact that the TIF_SSBD is inherited across execve(2) boundary will cause performance of applications that don't need SSBD but their predecessors have SSBD on to be unwittingly impacted especially if they write to memory a lot. To remedy this problem, a new PR_SPEC_DISABLE_NOEXEC argument for the PR_SET_SPECULATION_CTRL option of prctl(2) is added to allow applications to specify that the SSBD feature bit on the task structure should be cleared whenever a new program is being execve'ed. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Jiri Kosina <jikos@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Link: https://lkml.kernel.org/r/1547676096-3281-1-git-send-email-longman@redhat.com
2019-01-26x86/kernel: Mark expected switch-case fall-throughsGustavo A. R. Silva
In preparation to enable -Wimplicit-fallthrough by default, mark switch-case statements where fall-through is intentional, explicitly in order to fix a couple of -Wimplicit-fallthrough warnings. Warning level 3 was used: -Wimplicit-fallthrough=3. [ bp: Massasge and trim commit message. ] Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baoquan He <bhe@redhat.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: David Wang <davidwang@zhaoxin.com> Cc: Douglas Anderson <dianders@chromium.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pu Wen <puwen@hygon.cn> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190125183903.GA4712@embeddedor
2019-01-18x86/CPU/AMD: Set the CPB bit unconditionally on F17hJiaxun Yang
Some F17h models do not have CPB set in CPUID even though the CPU supports it. Set the feature bit unconditionally on all F17h. [ bp: Rewrite commit message and patch. ] Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Sherry Hurwitz <sherry.hurwitz@amd.com> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20181120030018.5185-1-jiaxun.yang@flygoat.com
2019-01-16x86/MCE/AMD: Carve out the MC4_MISC thresholding quirkShirish S
The MC4_MISC thresholding quirk needs to be applied during S5 -> S0 and S3 -> S0 state transitions, which follow different code paths. Carve it out into a separate function and call it mce_amd_feature_init() where the two code paths of the state transitions converge. [ bp: massage commit message and the carved out function. ] Signed-off-by: Shirish S <shirish.s@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1547651417-23583-3-git-send-email-shirish.s@amd.com
2019-01-15x86/MCE/AMD: Turn off MC4_MISC thresholding on all family 0x15 modelsShirish S
MC4_MISC thresholding is not supported on all family 0x15 processors, hence skip the x86_model check when applying the quirk. [ bp: massage commit message. ] Signed-off-by: Shirish S <shirish.s@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1547106849-3476-2-git-send-email-shirish.s@amd.com
2019-01-14x86/MCE: Switch to use the new generic UUID APIAndy Shevchenko
Switch the code to use the new, generic helpers. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190110153645.40649-1-andriy.shevchenko@linux.intel.com
2019-01-09x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINEWANG Chao
Commit 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support") replaced the RETPOLINE define with CONFIG_RETPOLINE checks. Remove the remaining pieces. [ bp: Massage commit message. ] Fixes: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support") Signed-off-by: WANG Chao <chao.wang@ucloud.cn> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Kees Cook <keescook@chromium.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: linux-kbuild@vger.kernel.org Cc: srinivas.eeda@oracle.com Cc: stable <stable@vger.kernel.org> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20181210163725.95977-1-chao.wang@ucloud.cn
2019-01-09x86/cache: Rename config option to CONFIG_X86_RESCTRLBorislav Petkov
CONFIG_RESCTRL is too generic. The final goal is to have a generic option called like this which is selected by the arch-specific ones CONFIG_X86_RESCTRL and CONFIG_ARM64_RESCTRL. The generic one will cover the resctrl filesystem and other generic and shared bits of functionality. Signed-off-by: Borislav Petkov <bp@suse.de> Suggested-by: Ingo Molnar <mingo@kernel.org> Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Babu Moger <babu.moger@amd.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: James Morse <james.morse@arm.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20190108171401.GC12235@zn.tnic