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2019-03-14perf/x86/intel: Implement support for TSX Force AbortPeter Zijlstra (Intel)2-3/+77
commit 400816f60c543153656ac74eaf7f36f6b7202378 upstream Skylake (and later) will receive a microcode update to address a TSX errata. This microcode will, on execution of a TSX instruction (speculative or not) use (clobber) PMC3. This update will also provide a new MSR to change this behaviour along with a CPUID bit to enumerate the presence of this new MSR. When the MSR gets set; the microcode will no longer use PMC3 but will Force Abort every TSX transaction (upon executing COMMIT). When TSX Force Abort (TFA) is allowed (default); the MSR gets set when PMC3 gets scheduled and cleared when, after scheduling, PMC3 is unused. When TFA is not allowed; clear PMC3 from all constraints such that it will not get used. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-14x86: Add TSX Force Abort CPUID/MSRPeter Zijlstra (Intel)2-0/+7
commit 52f64909409c17adf54fcf5f9751e0544ca3a6b4 upstream Skylake systems will receive a microcode update to address a TSX errata. This microcode will (by default) clobber PMC3 when TSX instructions are (speculatively or not) executed. It also provides an MSR to cause all TSX transaction to abort and preserve PMC3. Add the CPUID enumeration and MSR definition. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-14perf/x86/intel: Generalize dynamic constraint creationPeter Zijlstra (Intel)1-21/+30
commit 11f8b2d65ca9029591c8df26bb6bd063c312b7fe upstream Such that we can re-use it. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-14perf/x86/intel: Make cpuc allocations consistentPeter Zijlstra (Intel)3-22/+31
commit d01b1f96a82e5dd7841a1d39db3abfdaf95f70ab upstream The cpuc data structure allocation is different between fake and real cpuc's; use the same code to init/free both. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-14x86/PCI: Fixup RTIT_BAR of Intel Denverton Trace HubAlexander Shishkin1-0/+16
commit 2e095ce7b6ecce2f3e2ff330527f12056ed1e1a1 upstream. On Denverton's integration of the Intel(R) Trace Hub (for a reference and overview see Documentation/trace/intel_th.rst) the reported size of one of its resources (RTIT_BAR) doesn't match its actual size, which leads to overlaps with other devices' resources. In practice, it overlaps with XHCI MMIO space, which results in the xhci driver bailing out after seeing its registers as 0xffffffff, and perceived disappearance of all USB devices: intel_th_pci 0000:00:1f.7: enabling device (0004 -> 0006) xhci_hcd 0000:00:15.0: xHCI host controller not responding, assume dead xhci_hcd 0000:00:15.0: xHC not responding in xhci_irq, assume controller is dead xhci_hcd 0000:00:15.0: HC died; cleaning up usb 1-1: USB disconnect, device number 2 For this reason, we need to resize the RTIT_BAR on Denverton to its actual size, which in this case is 4MB. The corresponding erratum is DNV36 at the link below: DNV36. Processor Host Root Complex May Incorrectly Route Memory Accesses to Intel® Trace Hub Problem: The Intel® Trace Hub RTIT_BAR (B0:D31:F7 offset 20h) is reported as a 2KB memory range. Due to this erratum, the processor Host Root Complex will forward addresses from RTIT_BAR to RTIT_BAR + 4MB -1 to Intel® Trace Hub. Implication: Devices assigned within the RTIT_BAR to RTIT_BAR + 4MB -1 space may not function correctly. Workaround: A BIOS code change has been identified and may be implemented as a workaround for this erratum. Status: No Fix. Note that 5118ccd34780 ("intel_th: pci: Add Denverton SOC support") updates the Trace Hub driver so it claims the Denverton device, but the resource overlap exists regardless of whether that driver is loaded or that commit is included. Link: https://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/atom-c3000-family-spec-update.pdf Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> [bhelgaas: include erratum text, clarify relationship with 5118ccd34780] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-14x86_64: increase stack size for KASAN_EXTRAQian Cai1-0/+4
[ Upstream commit a8e911d13540487942d53137c156bd7707f66e5d ] If the kernel is configured with KASAN_EXTRA, the stack size is increasted significantly because this option sets "-fstack-reuse" to "none" in GCC [1]. As a result, it triggers stack overrun quite often with 32k stack size compiled using GCC 8. For example, this reproducer https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/syscalls/madvise/madvise06.c triggers a "corrupted stack end detected inside scheduler" very reliably with CONFIG_SCHED_STACK_END_CHECK enabled. There are just too many functions that could have a large stack with KASAN_EXTRA due to large local variables that have been called over and over again without being able to reuse the stacks. Some noticiable ones are size 7648 shrink_page_list 3584 xfs_rmap_convert 3312 migrate_page_move_mapping 3312 dev_ethtool 3200 migrate_misplaced_transhuge_page 3168 copy_process There are other 49 functions are over 2k in size while compiling kernel with "-Wframe-larger-than=" even with a related minimal config on this machine. Hence, it is too much work to change Makefiles for each object to compile without "-fsanitize-address-use-after-scope" individually. [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715#c23 Although there is a patch in GCC 9 to help the situation, GCC 9 probably won't be released in a few months and then it probably take another 6-month to 1-year for all major distros to include it as a default. Hence, the stack usage with KASAN_EXTRA can be revisited again in 2020 when GCC 9 is everywhere. Until then, this patch will help users avoid stack overrun. This has already been fixed for arm64 for the same reason via 6e8830674ea ("arm64: kasan: Increase stack size for KASAN_EXTRA"). Link: http://lkml.kernel.org/r/20190109215209.2903-1-cai@lca.pw Signed-off-by: Qian Cai <cai@lca.pw> 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: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-14x86/kexec: Don't setup EFI info if EFI runtime is not enabledKairui Song1-0/+3
[ Upstream commit 2aa958c99c7fd3162b089a1a56a34a0cdb778de1 ] Kexec-ing a kernel with "efi=noruntime" on the first kernel's command line causes the following null pointer dereference: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 #PF error: [normal kernel read fault] Call Trace: efi_runtime_map_copy+0x28/0x30 bzImage64_load+0x688/0x872 arch_kexec_kernel_image_load+0x6d/0x70 kimage_file_alloc_init+0x13e/0x220 __x64_sys_kexec_file_load+0x144/0x290 do_syscall_64+0x55/0x1a0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Just skip the EFI info setup if EFI runtime services are not enabled. [ bp: Massage commit message. ] Suggested-by: Dave Young <dyoung@redhat.com> Signed-off-by: Kairui Song <kasong@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: bhe@redhat.com Cc: David Howells <dhowells@redhat.com> Cc: erik.schmauss@intel.com Cc: fanc.fnst@cn.fujitsu.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: kexec@lists.infradead.org Cc: lenb@kernel.org Cc: linux-acpi@vger.kernel.org Cc: Philipp Rudo <prudo@linux.vnet.ibm.com> Cc: rafael.j.wysocki@intel.com Cc: robert.moore@intel.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: Yannik Sembritzki <yannik@sembritzki.me> Link: https://lkml.kernel.org/r/20190118111310.29589-2-kasong@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-14x86/microcode/amd: Don't falsely trick the late loading mechanismThomas Lendacky1-1/+1
[ Upstream commit 912139cfbfa6a2bc1da052314d2c29338dae1f6a ] 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 Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-14x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning ↵Wei Huang2-1/+9
to long mode [ Upstream commit b677dfae5aa197afc5191755a76a8727ffca538a ] In some old AMD KVM implementation, guest's EFER.LME bit is cleared by KVM when the hypervsior detects that the guest sets CR0.PG to 0. This causes the guest OS to reboot when it tries to return from 32-bit trampoline code because the CPU is in incorrect state: CR4.PAE=1, CR0.PG=1, CS.L=1, but EFER.LME=0. As a precaution, set EFER.LME=1 as part of long mode activation procedure. This extra step won't cause any harm when Linux is booted on a bare-metal machine. Signed-off-by: Wei Huang <wei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: bp@alien8.de Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20190104054411.12489-1-wei@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-10x86/boot/compressed/64: Do not read legacy ROM on EFI systemKirill A. Shutemov1-3/+16
commit 6f913de3231e1d70a871135b38219da7810df218 upstream. EFI systems do not necessarily provide a legacy ROM. If the ROM is missing the memory is not mapped at all. Trying to dereference values in the legacy ROM area leads to a crash on Macbook Pro. Only look for values in the legacy ROM area for non-EFI system. Fixes: 3548e131ec6a ("x86/boot/compressed/64: Find a place for 32-bit trampoline") Reported-by: Pitam Mitra <pitamm@gmail.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Bockjoo Kim <bockjoo@phys.ufl.edu> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190219075224.35058-1-kirill.shutemov@linux.intel.com Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202351 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10x86/CPU/AMD: Set the CPB bit unconditionally on F17hJiaxun Yang1-5/+3
commit 0237199186e7a4aa5310741f0a6498a20c820fd7 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05x86/uaccess: Don't leak the AC flag into __put_user() value evaluationAndy Lutomirski1-3/+4
commit 2a418cf3f5f1caf911af288e978d61c9844b0695 upstream. When calling __put_user(foo(), ptr), the __put_user() macro would call foo() in between __uaccess_begin() and __uaccess_end(). If that code were buggy, then those bugs would be run without SMAP protection. Fortunately, there seem to be few instances of the problem in the kernel. Nevertheless, __put_user() should be fixed to avoid doing this. Therefore, evaluate __put_user()'s argument before setting AC. This issue was noticed when an objtool hack by Peter Zijlstra complained about genregs_get() and I compared the assembly output to the C source. [ bp: Massage commit message and fixed up whitespace. ] Fixes: 11f1a4b9755f ("x86: reorganize SMAP handling in user space accesses") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20190225125231.845656645@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05KVM: nSVM: clear events pending from svm_complete_interrupts() when exiting ↵Vitaly Kuznetsov1-0/+8
to L1 [ Upstream commit 619ad846fc3452adaf71ca246c5aa711e2055398 ] kvm-unit-tests' eventinj "NMI failing on IDT" test results in NMI being delivered to the host (L1) when it's running nested. The problem seems to be: svm_complete_interrupts() raises 'nmi_injected' flag but later we decide to reflect EXIT_NPF to L1. The flag remains pending and we do NMI injection upon entry so it got delivered to L1 instead of L2. It seems that VMX code solves the same issue in prepare_vmcs12(), this was introduced with code refactoring in commit 5f3d5799974b ("KVM: nVMX: Rework event injection and recovery"). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-05svm: Fix AVIC incomplete IPI emulationSuravee Suthikulpanit1-15/+4
[ Upstream commit bb218fbcfaaa3b115d4cd7a43c0ca164f3a96e57 ] In case of incomplete IPI with invalid interrupt type, the current SVM driver does not properly emulate the IPI, and fails to boot FreeBSD guests with multiple vcpus when enabling AVIC. Fix this by update APIC ICR high/low registers, which also emulate sending the IPI. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-05x86/mm/mem_encrypt: Fix erroneous sizeof()Peng Hao1-2/+2
[ Upstream commit bf7d28c53453ea904584960de55e33e03b9d93b1 ] Using sizeof(pointer) for determining the size of a memset() only works when the size of the pointer and the size of type to which it points are the same. For pte_t this is only true for 64bit and 32bit-NONPAE. On 32bit PAE systems this is wrong as the pointer size is 4 byte but the PTE entry is 8 bytes. It's actually not a real world issue as this code depends on 64bit, but it's wrong nevertheless. Use sizeof(*p) for correctness sake. Fixes: aad983913d77 ("x86/mm/encrypt: Simplify sme_populate_pgd() and sme_populate_pgd_large()") Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: dave.hansen@linux.intel.com Cc: peterz@infradead.org Cc: luto@kernel.org Link: https://lkml.kernel.org/r/1546065252-97996-1-git-send-email-peng.hao2@zte.com.cn Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-05irq/matrix: Spread managed interrupts on allocationDou Liyang1-5/+4
[ Upstream commit 76f99ae5b54d48430d1f0c5512a84da0ff9761e0 ] Linux spreads out the non managed interrupt across the possible target CPUs to avoid vector space exhaustion. Managed interrupts are treated differently, as for them the vectors are reserved (with guarantee) when the interrupt descriptors are initialized. When the interrupt is requested a real vector is assigned. The assignment logic uses the first CPU in the affinity mask for assignment. If the interrupt has more than one CPU in the affinity mask, which happens when a multi queue device has less queues than CPUs, then doing the same search as for non managed interrupts makes sense as it puts the interrupt on the least interrupt plagued CPU. For single CPU affine vectors that's obviously a NOOP. Restructre the matrix allocation code so it does the 'best CPU' search, add the sanity check for an empty affinity mask and adapt the call site in the x86 vector management code. [ tglx: Added the empty mask check to the core and improved change log ] Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180908175838.14450-2-dou_liyang@163.com Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27kvm: x86: Return LA57 feature based on hardware capabilityYu Zhang1-0/+4
commit 511da98d207d5c0675a10351b01e37cbe50a79e5 upstream. Previously, 'commit 372fddf70904 ("x86/mm: Introduce the 'no5lvl' kernel parameter")' cleared X86_FEATURE_LA57 in boot_cpu_data, if Linux chooses to not run in 5-level paging mode. Yet boot_cpu_data is queried by do_cpuid_ent() as the host capability later when creating vcpus, and Qemu will not be able to detect this feature and create VMs with LA57 feature. As discussed earlier, VMs can still benefit from extended linear address width, e.g. to enhance features like ASLR. So we would like to fix this, by return the true hardware capability when Qemu queries. Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27always clear the X2APIC_ENABLE bit for PV guestTalons Lee1-4/+1
[ Upstream commit 5268c8f39e0efef81af2aaed160272d9eb507beb ] Commit e657fcc clears cpu capability bit instead of using fake cpuid value, the EXTD should always be off for PV guest without depending on cpuid value. So remove the cpuid check in xen_read_msr_safe() to always clear the X2APIC_ENABLE bit. Signed-off-by: Talons Lee <xin.li@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20x86/a.out: Clear the dump structure initiallyBorislav Petkov1-2/+4
commit 10970e1b4be9c74fce8ab6e3c34a7d718f063f2c upstream. dump_thread32() in aout_core_dump() does not clear the user32 structure allocated on the stack as the first thing on function entry. As a result, the dump.u_comm, dump.u_ar0 and dump.signal which get assigned before the clearing, get overwritten. Rename that function to fill_dump() to make it clear what it does and call it first thing. This was caught while staring at a patch by Derek Robson <robsonde@gmail.com>. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Derek Robson <robsonde@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Matz <matz@suse.de> Cc: x86@kernel.org Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20190202005512.3144-1-robsonde@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20x86/platform/UV: Use efi_runtime_lock to serialise BIOS callsHedi Berriche2-3/+28
commit f331e766c4be33f4338574f3c9f7f77e98ab4571 upstream. Calls into UV firmware must be protected against concurrency, expose the efi_runtime_lock to the UV platform, and use it to serialise UV BIOS calls. Signed-off-by: Hedi Berriche <hedi.berriche@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Russ Anderson <rja@hpe.com> Reviewed-by: Dimitri Sivanich <sivanich@hpe.com> Reviewed-by: Mike Travis <mike.travis@hpe.com> Cc: Andy Shevchenko <andy@infradead.org> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Darren Hart <dvhart@infradead.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-efi <linux-efi@vger.kernel.org> Cc: platform-driver-x86@vger.kernel.org Cc: stable@vger.kernel.org # v4.9+ Cc: Steve Wahl <steve.wahl@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20kvm: vmx: Fix entry number check for add_atomic_switch_msr()Xiaoyao Li1-1/+2
commit 98ae70cc476e833332a2c6bb72f941a25f0de226 upstream. Commit ca83b4a7f2d068da79a0 ("x86/KVM/VMX: Add find_msr() helper function") introduces the helper function find_msr(), which returns -ENOENT when not find the msr in vmx->msr_autoload.guest/host. Correct checking contion of no more available entry in vmx->msr_autoload. Fixes: ca83b4a7f2d0 ("x86/KVM/VMX: Add find_msr() helper function") Cc: stable@vger.kernel.org Signed-off-by: Xiaoyao Li <xiaoyao.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20x86/kvm/nVMX: read from MSR_IA32_VMX_PROCBASED_CTLS2 only when it is availableVitaly Kuznetsov1-3/+5
commit 6b1971c694975e49af302229202c0043568b1791 upstream. SDM says MSR_IA32_VMX_PROCBASED_CTLS2 is only available "If (CPUID.01H:ECX.[5] && IA32_VMX_PROCBASED_CTLS[63])". It was found that some old cpus (namely "Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz (family: 0x6, model: 0xf, stepping: 0x6") don't have it. Add the missing check. Reported-by: Zdenek Kaspar <zkaspar82@gmail.com> Tested-by: Zdenek Kaspar <zkaspar82@gmail.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20perf/x86: Add check_period PMU callbackJiri Olsa3-2/+37
commit 81ec3f3c4c4d78f2d3b6689c9816bfbdf7417dbb upstream. Vince (and later on Ravi) reported crashes in the BTS code during fuzzing with the following backtrace: general protection fault: 0000 [#1] SMP PTI ... RIP: 0010:perf_prepare_sample+0x8f/0x510 ... Call Trace: <IRQ> ? intel_pmu_drain_bts_buffer+0x194/0x230 intel_pmu_drain_bts_buffer+0x160/0x230 ? tick_nohz_irq_exit+0x31/0x40 ? smp_call_function_single_interrupt+0x48/0xe0 ? call_function_single_interrupt+0xf/0x20 ? call_function_single_interrupt+0xa/0x20 ? x86_schedule_events+0x1a0/0x2f0 ? x86_pmu_commit_txn+0xb4/0x100 ? find_busiest_group+0x47/0x5d0 ? perf_event_set_state.part.42+0x12/0x50 ? perf_mux_hrtimer_restart+0x40/0xb0 intel_pmu_disable_event+0xae/0x100 ? intel_pmu_disable_event+0xae/0x100 x86_pmu_stop+0x7a/0xb0 x86_pmu_del+0x57/0x120 event_sched_out.isra.101+0x83/0x180 group_sched_out.part.103+0x57/0xe0 ctx_sched_out+0x188/0x240 ctx_resched+0xa8/0xd0 __perf_event_enable+0x193/0x1e0 event_function+0x8e/0xc0 remote_function+0x41/0x50 flush_smp_call_function_queue+0x68/0x100 generic_smp_call_function_single_interrupt+0x13/0x30 smp_call_function_single_interrupt+0x3e/0xe0 call_function_single_interrupt+0xf/0x20 </IRQ> The reason is that while event init code does several checks for BTS events and prevents several unwanted config bits for BTS event (like precise_ip), the PERF_EVENT_IOC_PERIOD allows to create BTS event without those checks being done. Following sequence will cause the crash: If we create an 'almost' BTS event with precise_ip and callchains, and it into a BTS event it will crash the perf_prepare_sample() function because precise_ip events are expected to come in with callchain data initialized, but that's not the case for intel_pmu_drain_bts_buffer() caller. Adding a check_period callback to be called before the period is changed via PERF_EVENT_IOC_PERIOD. It will deny the change if the event would become BTS. Plus adding also the limit_period check as well. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20190204123532.GA4794@krava Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20kvm: sev: Fail KVM_SEV_INIT if already initializedDavid Rientjes1-0/+3
[ Upstream commit 3f14a89d1132dcae3c8ce6721c6ef51f6e6d9b5f ] By code inspection, it was found that multiple calls to KVM_SEV_INIT could deplete asid bits and overwrite kvm_sev_info's regions_list. Multiple calls to KVM_SVM_INIT is not likely to occur with QEMU, but this should likely be fixed anyway. This code is serialized by kvm->lock. Fixes: 1654efcbc431 ("KVM: SVM: Add KVM_SEV_INIT command") Reported-by: Cfir Cohen <cfir@google.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12perf/x86/intel: Delay memory deallocation until x86_pmu_dead_cpu()Peter Zijlstra1-2/+8
commit 602cae04c4864bb3487dfe4c2126c8d9e7e1614a upstream. intel_pmu_cpu_prepare() allocated memory for ->shared_regs among other members of struct cpu_hw_events. This memory is released in intel_pmu_cpu_dying() which is wrong. The counterpart of the intel_pmu_cpu_prepare() callback is x86_pmu_dead_cpu(). Otherwise if the CPU fails on the UP path between CPUHP_PERF_X86_PREPARE and CPUHP_AP_PERF_X86_STARTING then it won't release the memory but allocate new memory on the next attempt to online the CPU (leaking the old memory). Also, if the CPU down path fails between CPUHP_AP_PERF_X86_STARTING and CPUHP_PERF_X86_PREPARE then the CPU will go back online but never allocate the memory that was released in x86_pmu_dying_cpu(). Make the memory allocation/free symmetrical in regard to the CPU hotplug notifier by moving the deallocation to intel_pmu_cpu_dead(). This started in commit: a7e3ed1e47011 ("perf: Add support for supplementary event registers"). In principle the bug was introduced in v2.6.39 (!), but it will almost certainly not backport cleanly across the big CPU hotplug rewrite between v4.7-v4.15... [ bigeasy: Added patch description. ] [ mingo: Added backporting guidance. ] Reported-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With developer hat on Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With maintainer hat on Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: bp@alien8.de Cc: hpa@zytor.com Cc: jolsa@kernel.org Cc: kan.liang@linux.intel.com Cc: namhyung@kernel.org Cc: <stable@vger.kernel.org> Fixes: a7e3ed1e47011 ("perf: Add support for supplementary event registers"). Link: https://lkml.kernel.org/r/20181219165350.6s3jvyxbibpvlhtq@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org> [ He Zhe: Fixes conflict caused by missing disable_counter_freeze which is introduced since v4.20 af3bdb991a5cb. ] Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12x86/MCE: Initialize mce.bank in the case of a fatal error in mce_no_way_out()Tony Luck1-0/+1
commit d28af26faa0b1daf3c692603d46bc4687c16f19e upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12perf/x86/intel/uncore: Add Node ID maskKan Liang1-1/+3
commit 9e63a7894fd302082cf3627fe90844421a6cbe7f upstream. Some PCI uncore PMUs cannot be registered on an 8-socket system (HPE Superdome Flex). To understand which Socket the PCI uncore PMUs belongs to, perf retrieves the local Node ID of the uncore device from CPUNODEID(0xC0) of the PCI configuration space, and the mapping between Socket ID and Node ID from GIDNIDMAP(0xD4). The Socket ID can be calculated accordingly. The local Node ID is only available at bit 2:0, but current code doesn't mask it. If a BIOS doesn't clear the rest of the bits, an incorrect Node ID will be fetched. Filter the Node ID by adding a mask. Reported-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> # v3.7+ Fixes: 7c94ee2e0917 ("perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support") Link: https://lkml.kernel.org/r/1548600794-33162-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVMJosh Poimboeuf2-2/+3
commit b284909abad48b07d3071a9fc9b5692b3e64914b upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12KVM: nVMX: unconditionally cancel preemption timer in free_nested ↵Peter Shier1-0/+1
(CVE-2019-7221) commit ecec76885bcfe3294685dc363fd1273df0d5d65f upstream. Bugzilla: 1671904 There are multiple code paths where an hrtimer may have been started to emulate an L1 VMX preemption timer that can result in a call to free_nested without an intervening L2 exit where the hrtimer is normally cancelled. Unconditionally cancel in free_nested to cover all cases. Embargoed until Feb 7th 2019. Signed-off-by: Peter Shier <pshier@google.com> Reported-by: Jim Mattson <jmattson@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reported-by: Felix Wilhelm <fwilhelm@google.com> Cc: stable@kernel.org Message-Id: <20181011184646.154065-1-pshier@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222)Paolo Bonzini1-0/+7
commit 353c0956a618a07ba4bbe7ad00ff29fe70e8412a upstream. Bugzilla: 1671930 Emulation of certain instructions (VMXON, VMCLEAR, VMPTRLD, VMWRITE with memory operand, INVEPT, INVVPID) can incorrectly inject a page fault when passed an operand that points to an MMIO address. The page fault will use uninitialized kernel stack memory as the CR2 and error code. The right behavior would be to abort the VM with a KVM_EXIT_INTERNAL_ERROR exit to userspace; however, it is not an easy fix, so for now just ensure that the error code and CR2 are zero. Embargoed until Feb 7th 2019. Reported-by: Felix Wilhelm <fwilhelm@google.com> Cc: stable@kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12KVM: x86: svm: report MSR_IA32_MCG_EXT_CTL as unsupportedVitaly Kuznetsov1-0/+7
[ Upstream commit e87555e550cef4941579cd879759a7c0dee24e68 ] AMD doesn't seem to implement MSR_IA32_MCG_EXT_CTL and svm code in kvm knows nothing about it, however, this MSR is among emulated_msrs and thus returned with KVM_GET_MSR_INDEX_LIST. The consequent KVM_GET_MSRS, of course, fails. Report the MSR as unsupported to not confuse userspace. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12x86/fpu: Add might_fault() to user_insn()Sebastian Andrzej Siewior1-0/+3
[ Upstream commit 6637401c35b2f327a35d27f44bda05e327f2f017 ] Every user of user_insn() passes an user memory pointer to this macro. Add might_fault() to user_insn() so we can spot users which are using this macro in sections where page faulting is not allowed. [ bp: Space it out to make it more visible. ] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Rik van Riel <riel@surriel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm ML <kvm@vger.kernel.org> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20181128222035.2996-6-bigeasy@linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12x86/PCI: Fix Broadcom CNB20LE unintended sign extension (redux)Colin Ian King1-2/+2
[ Upstream commit 53bb565fc5439f2c8c57a786feea5946804aa3e9 ] In the expression "word1 << 16", word1 starts as u16, but is promoted to a signed int, then sign-extended to resource_size_t, which is probably not what was intended. Cast to resource_size_t to avoid the sign extension. This fixes an identical issue as fixed by commit 0b2d70764bb3 ("x86/PCI: Fix Broadcom CNB20LE unintended sign extension") back in 2014. Detected by CoverityScan, CID#138749, 138750 ("Unintended sign extension") Fixes: 3f6ea84a3035 ("PCI: read memory ranges out of Broadcom CNB20LE host bridge") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-31x86/entry/64/compat: Fix stack switching for XEN PVJan Beulich1-2/+4
commit fc24d75a7f91837d7918e40719575951820b2b8f upstream. While in the native case entry into the kernel happens on the trampoline stack, PV Xen kernels get entered with the current thread stack right away. Hence source and destination stacks are identical in that case, and special care is needed. Other than in sync_regs() the copying done on the INT80 path isn't NMI / #MC safe, as either of these events occurring in the middle of the stack copying would clobber data on the (source) stack. There is similar code in interrupt_entry() and nmi(), but there is no fixup required because those code paths are unreachable in XEN PV guests. [ tglx: Sanitized subject, changelog, Fixes tag and stable mail address. Sigh ] Fixes: 7f2590a110b8 ("x86/entry/64: Use a per-CPU trampoline stack for IDT entries") Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Cc: xen-devel@lists.xenproject.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/5C3E1128020000780020DFAD@prv1-mh.provo.novell.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31x86/kaslr: Fix incorrect i8254 outb() parametersDaniel Drake1-2/+2
commit 7e6fc2f50a3197d0e82d1c0e86282976c9e6c8a4 upstream. The outb() function takes parameters value and port, in that order. Fix the parameters used in the kalsr i8254 fallback code. Fixes: 5bfce5ef55cb ("x86, kaslr: Provide randomness functions") Signed-off-by: Daniel Drake <drake@endlessm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: linux@endlessm.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190107034024.15005-1-drake@endlessm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31x86/pkeys: Properly copy pkey state at fork()Dave Hansen1-0/+18
commit a31e184e4f69965c99c04cc5eb8a4920e0c63737 upstream. Memory protection key behavior should be the same in a child as it was in the parent before a fork. But, there is a bug that resets the state in the child at fork instead of preserving it. The creation of new mm's is a bit convoluted. At fork(), the code does: 1. memcpy() the parent mm to initialize child 2. mm_init() to initalize some select stuff stuff 3. dup_mmap() to create true copies that memcpy() did not do right For pkeys two bits of state need to be preserved across a fork: 'execute_only_pkey' and 'pkey_allocation_map'. Those are preserved by the memcpy(), but mm_init() invokes init_new_context() which overwrites 'execute_only_pkey' and 'pkey_allocation_map' with "new" values. The author of the code erroneously believed that init_new_context is *only* called at execve()-time. But, alas, init_new_context() is used at execve() and fork(). The result is that, after a fork(), the child's pkey state ends up looking like it does after an execve(), which is totally wrong. pkeys that are already allocated can be allocated again, for instance. To fix this, add code called by dup_mmap() to copy the pkey state from parent to child explicitly. Also add a comment above init_new_context() to make it more clear to the next poor sod what this code is used for. Fixes: e8c24d3a23a ("x86/pkeys: Allocation/free syscalls") Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: peterz@infradead.org Cc: mpe@ellerman.id.au Cc: will.deacon@arm.com Cc: luto@kernel.org Cc: jroedel@suse.de Cc: stable@vger.kernel.org Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Will Deacon <will.deacon@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Joerg Roedel <jroedel@suse.de> Link: https://lkml.kernel.org/r/20190102215655.7A69518C@viggo.jf.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31KVM/nVMX: Do not validate that posted_intr_desc_addr is page alignedKarimAllah Ahmed1-1/+1
commit 22a7cdcae6a4a3c8974899e62851d270956f58ce upstream. The spec only requires the posted interrupt descriptor address to be 64-bytes aligned (i.e. bits[0:5] == 0). Using page_address_valid also forces the address to be page aligned. Only validate that the address does not cross the maximum physical address without enforcing a page alignment. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.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: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Fixes: 6de84e581c0 ("nVMX x86: check posted-interrupt descriptor addresss on vmentry of L2") Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Krish Sadhuhan <krish.sadhukhan@oracle.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> From: Mark Mielke <mark.mielke@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31kvm: x86/vmx: Use kzalloc for cached_vmcs12Tom Roeder1-4/+8
commit 3a33d030daaa7c507e1c12d5adcf828248429593 upstream. This changes the allocation of cached_vmcs12 to use kzalloc instead of kmalloc. This removes the information leak found by Syzkaller (see Reported-by) in this case and prevents similar leaks from happening based on cached_vmcs12. It also changes vmx_get_nested_state to copy out the full 4k VMCS12_SIZE in copy_to_user rather than only the size of the struct. Tested: rebuilt against head, booted, and ran the syszkaller repro https://syzkaller.appspot.com/text?tag=ReproC&x=174efca3400000 without observing any problems. Reported-by: syzbot+ded1696f6b50b615b630@syzkaller.appspotmail.com Fixes: 8fcc4b5923af5de58b80b53a069453b135693304 Cc: stable@vger.kernel.org Signed-off-by: Tom Roeder <tmroeder@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31KVM: x86: WARN_ONCE if sending a PV IPI returns a fatal errorSean Christopherson1-2/+5
commit de81c2f912ef57917bdc6d63b410c534c3e07982 upstream. KVM hypercalls return a negative value error code in case of a fatal error, e.g. when the hypercall isn't supported or was made with invalid parameters. WARN_ONCE on fatal errors when sending PV IPIs as any such error all but guarantees an SMP system will hang due to a missing IPI. Fixes: aaffcfd1e82d ("KVM: X86: Implement PV IPIs in linux guest") Cc: stable@vger.kernel.org Cc: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31KVM: x86: Fix PV IPIs for 32-bit KVM hostSean Christopherson1-1/+1
commit 1ed199a41c70ad7bfaee8b14f78e791fcf43b278 upstream. The recognition of the KVM_HC_SEND_IPI hypercall was unintentionally wrapped in "#ifdef CONFIG_X86_64", causing 32-bit KVM hosts to reject any and all PV IPI requests despite advertising the feature. This results in all KVM paravirtualized guests hanging during SMP boot due to IPIs never being delivered. Fixes: 4180bf1b655a ("KVM: X86: Implement "send IPI" hypercall") Cc: stable@vger.kernel.org Cc: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31KVM: x86: Fix single-step debuggingAlexander Popov1-2/+1
commit 5cc244a20b86090c087073c124284381cdf47234 upstream. The single-step debugging of KVM guests on x86 is broken: if we run gdb 'stepi' command at the breakpoint when the guest interrupts are enabled, RIP always jumps to native_apic_mem_write(). Then other nasty effects follow. Long investigation showed that on Jun 7, 2017 the commit c8401dda2f0a00cd25c0 ("KVM: x86: fix singlestepping over syscall") introduced the kvm_run.debug corruption: kvm_vcpu_do_singlestep() can be called without X86_EFLAGS_TF set. Let's fix it. Please consider that for -stable. Signed-off-by: Alexander Popov <alex.popov@linux.com> Cc: stable@vger.kernel.org Fixes: c8401dda2f0a00cd25c0 ("KVM: x86: fix singlestepping over syscall") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-26x86/topology: Use total_cpus for max logical packages calculationHui Wang1-1/+1
[ Upstream commit aa02ef099cff042c2a9109782ec2bf1bffc955d4 ] nr_cpu_ids can be limited on the command line via nr_cpus=. This can break the logical package management because it results in a smaller number of packages while in kdump kernel. Check below case: There is a two sockets system, each socket has 8 cores, which has 16 logical cpus while HT was turn on. 0 1 2 3 4 5 6 7 | 16 17 18 19 20 21 22 23 cores on socket 0 threads on socket 0 8 9 10 11 12 13 14 15 | 24 25 26 27 28 29 30 31 cores on socket 1 threads on socket 1 While starting the kdump kernel with command line option nr_cpus=16 panic was triggered on one of the cpus 24-31 eg. 26, then online cpu will be 1-15, 26(cpu 0 was disabled in kdump), ncpus will be 16 and __max_logical_packages will be 1, but actually two packages were booted on. This issue can reproduced by set kdump option nr_cpus=<real physical core numbers>, and then trigger panic on last socket's thread, for example: taskset -c 26 echo c > /proc/sysrq-trigger Use total_cpus which will not be limited by nr_cpus command line to calculate the value of __max_logical_packages. Signed-off-by: Hui Wang <john.wanghui@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <guijianfeng@huawei.com> Cc: <wencongyang2@huawei.com> Cc: <douliyang1@huawei.com> Cc: <qiaonuohan@huawei.com> Link: https://lkml.kernel.org/r/20181107023643.22174-1-john.wanghui@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26x86/mce: Fix -Wmissing-prototypes warningsBorislav Petkov4-7/+10
[ Upstream commit 68b5e4326e4b8ac9080835005d8254fed0fb3c56 ] Add the proper includes and make smca_get_name() static. Fix an actual bug too which the warning triggered: arch/x86/kernel/cpu/mcheck/therm_throt.c:395:39: error: conflicting \ types for ‘smp_thermal_interrupt’ asmlinkage __visible void __irq_entry smp_thermal_interrupt(struct pt_regs *r) ^~~~~~~~~~~~~~~~~~~~~ In file included from arch/x86/kernel/cpu/mcheck/therm_throt.c:29: ./arch/x86/include/asm/traps.h:107:17: note: previous declaration of \ ‘smp_thermal_interrupt’ was here asmlinkage void smp_thermal_interrupt(void); Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Yi Wang <wang.yi59@zte.com.cn> Cc: Michael Matz <matz@suse.de> Cc: x86@kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1811081633160.1549@nanos.tec.linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-22xen: Fix x86 sched_clock() interface for xenJuergen Gross1-3/+9
commit 867cefb4cb1012f42cada1c7d1f35ac8dd276071 upstream. Commit f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") broke Xen guest time handling across migration: [ 187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done. [ 187.251137] OOM killer disabled. [ 187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 187.252299] suspending xenstore... [ 187.266987] xen:grant_table: Grant tables using version 1 layout [18446743811.706476] OOM killer enabled. [18446743811.706478] Restarting tasks ... done. [18446743811.720505] Setting capacity to 16777216 Fix that by setting xen_sched_clock_offset at resume time to ensure a monotonic clock value. [boris: replaced pr_info() with pr_info_once() in xen_callback_vector() to avoid printing with incorrect timestamp during resume (as we haven't re-adjusted the clock yet)] Fixes: f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") Cc: <stable@vger.kernel.org> # 4.11 Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-17x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINEWANG Chao1-1/+1
commit e4f358916d528d479c3c12bd2fd03f2d5a576380 upstream. 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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13x86/dump_pagetables: Fix LDT remap address markerKirill A. Shutemov1-5/+2
[ Upstream commit 254eb5505ca0ca749d3a491fc6668b6c16647a99 ] The LDT remap placement has been changed. It's now placed before the direct mapping in the kernel virtual address space for both paging modes. Change address markers order accordingly. Fixes: d52888aa2753 ("x86/mm: Move LDT remap out of KASLR region on 5-level paging") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: luto@kernel.org Cc: peterz@infradead.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: bhe@redhat.com Cc: hans.van.kranenburg@mendix.com Cc: linux-mm@kvack.org Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20181130202328.65359-3-kirill.shutemov@linux.intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-13x86/mm: Fix guard hole handlingKirill A. Shutemov3-9/+15
[ Upstream commit 16877a5570e0c5f4270d5b17f9bab427bcae9514 ] There is a guard hole at the beginning of the kernel address space, also used by hypervisors. It occupies 16 PGD entries. This reserved range is not defined explicitely, it is calculated relative to other entities: direct mapping and user space ranges. The calculation got broken by recent changes of the kernel memory layout: LDT remap range is now mapped before direct mapping and makes the calculation invalid. The breakage leads to crash on Xen dom0 boot[1]. Define the reserved range explicitely. It's part of kernel ABI (hypervisors expect it to be stable) and must not depend on changes in the rest of kernel memory layout. [1] https://lists.xenproject.org/archives/html/xen-devel/2018-11/msg03313.html Fixes: d52888aa2753 ("x86/mm: Move LDT remap out of KASLR region on 5-level paging") Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: luto@kernel.org Cc: peterz@infradead.org Cc: boris.ostrovsky@oracle.com Cc: bhe@redhat.com Cc: linux-mm@kvack.org Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20181130202328.65359-2-kirill.shutemov@linux.intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-09KVM: nVMX: Free the VMREAD/VMWRITE bitmaps if alloc_kvm_area() failsSean Christopherson1-2/+5
commit 1b3ab5ad1b8ad99bae76ec583809c5f5a31c707c upstream. Fixes: 34a1cd60d17f ("kvm: x86: vmx: move some vmx setting from vmx_init() to hardware_setup()") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09KVM: x86: Use jmp to invoke kvm_spurious_fault() from .fixupSean Christopherson1-1/+1
commit e81434995081fd7efb755fd75576b35dbb0850b1 upstream. ____kvm_handle_fault_on_reboot() provides a generic exception fixup handler that is used to cleanly handle faults on VMX/SVM instructions during reboot (or at least try to). If there isn't a reboot in progress, ____kvm_handle_fault_on_reboot() treats any exception as fatal to KVM and invokes kvm_spurious_fault(), which in turn generates a BUG() to get a stack trace and die. When it was originally added by commit 4ecac3fd6dc2 ("KVM: Handle virtualization instruction #UD faults during reboot"), the "call" to kvm_spurious_fault() was handcoded as PUSH+JMP, where the PUSH'd value is the RIP of the faulting instructing. The PUSH+JMP trickery is necessary because the exception fixup handler code lies outside of its associated function, e.g. right after the function. An actual CALL from the .fixup code would show a slightly bogus stack trace, e.g. an extra "random" function would be inserted into the trace, as the return RIP on the stack would point to no known function (and the unwinder will likely try to guess who owns the RIP). Unfortunately, the JMP was replaced with a CALL when the macro was reworked to not spin indefinitely during reboot (commit b7c4145ba2eb "KVM: Don't spin on virt instruction faults during reboot"). This causes the aforementioned behavior where a bogus function is inserted into the stack trace, e.g. my builds like to blame free_kvm_area(). Revert the CALL back to a JMP. The changelog for commit b7c4145ba2eb ("KVM: Don't spin on virt instruction faults during reboot") contains nothing that indicates the switch to CALL was deliberate. This is backed up by the fact that the PUSH <insn RIP> was left intact. Note that an alternative to the PUSH+JMP magic would be to JMP back to the "real" code and CALL from there, but that would require adding a JMP in the non-faulting path to avoid calling kvm_spurious_fault() and would add no value, i.e. the stack trace would be the same. Using CALL: ------------[ cut here ]------------ kernel BUG at /home/sean/go/src/kernel.org/linux/arch/x86/kvm/x86.c:356! invalid opcode: 0000 [#1] SMP CPU: 4 PID: 1057 Comm: qemu-system-x86 Not tainted 4.20.0-rc6+ #75 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:kvm_spurious_fault+0x5/0x10 [kvm] Code: <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 55 49 89 fd 41 RSP: 0018:ffffc900004bbcc8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffffffffff RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888273fd8000 R08: 00000000000003e8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000784 R12: ffffc90000371fb0 R13: 0000000000000000 R14: 000000026d763cf4 R15: ffff888273fd8000 FS: 00007f3d69691700(0000) GS:ffff888277800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f89bc56fe0 CR3: 0000000271a5a001 CR4: 0000000000362ee0 Call Trace: free_kvm_area+0x1044/0x43ea [kvm_intel] ? vmx_vcpu_run+0x156/0x630 [kvm_intel] ? kvm_arch_vcpu_ioctl_run+0x447/0x1a40 [kvm] ? kvm_vcpu_ioctl+0x368/0x5c0 [kvm] ? kvm_vcpu_ioctl+0x368/0x5c0 [kvm] ? __set_task_blocked+0x38/0x90 ? __set_current_blocked+0x50/0x60 ? __fpu__restore_sig+0x97/0x490 ? do_vfs_ioctl+0xa1/0x620 ? __x64_sys_futex+0x89/0x180 ? ksys_ioctl+0x66/0x70 ? __x64_sys_ioctl+0x16/0x20 ? do_syscall_64+0x4f/0x100 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 Modules linked in: vhost_net vhost tap kvm_intel kvm irqbypass bridge stp llc ---[ end trace 9775b14b123b1713 ]--- Using JMP: ------------[ cut here ]------------ kernel BUG at /home/sean/go/src/kernel.org/linux/arch/x86/kvm/x86.c:356! invalid opcode: 0000 [#1] SMP CPU: 6 PID: 1067 Comm: qemu-system-x86 Not tainted 4.20.0-rc6+ #75 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:kvm_spurious_fault+0x5/0x10 [kvm] Code: <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 55 49 89 fd 41 RSP: 0018:ffffc90000497cd0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffffffffff RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88827058bd40 R08: 00000000000003e8 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000784 R12: ffffc90000369fb0 R13: 0000000000000000 R14: 00000003c8fc6642 R15: ffff88827058bd40 FS: 00007f3d7219e700(0000) GS:ffff888277900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3d64001000 CR3: 0000000271c6b004 CR4: 0000000000362ee0 Call Trace: vmx_vcpu_run+0x156/0x630 [kvm_intel] ? kvm_arch_vcpu_ioctl_run+0x447/0x1a40 [kvm] ? kvm_vcpu_ioctl+0x368/0x5c0 [kvm] ? kvm_vcpu_ioctl+0x368/0x5c0 [kvm] ? __set_task_blocked+0x38/0x90 ? __set_current_blocked+0x50/0x60 ? __fpu__restore_sig+0x97/0x490 ? do_vfs_ioctl+0xa1/0x620 ? __x64_sys_futex+0x89/0x180 ? ksys_ioctl+0x66/0x70 ? __x64_sys_ioctl+0x16/0x20 ? do_syscall_64+0x4f/0x100 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 Modules linked in: vhost_net vhost tap kvm_intel kvm irqbypass bridge stp llc ---[ end trace f9daedb85ab3ddba ]--- Fixes: b7c4145ba2eb ("KVM: Don't spin on virt instruction faults during reboot") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09x86/mm: Drop usage of __flush_tlb_all() in kernel_physical_mapping_init()Dan Williams1-6/+0
commit ba6f508d0ec4adb09f0a939af6d5e19cdfa8667d upstream. Commit: f77084d96355 "x86/mm/pat: Disable preemption around __flush_tlb_all()" addressed a case where __flush_tlb_all() is called without preemption being disabled. It also left a warning to catch other cases where preemption is not disabled. That warning triggers for the memory hotplug path which is also used for persistent memory enabling: WARNING: CPU: 35 PID: 911 at ./arch/x86/include/asm/tlbflush.h:460 RIP: 0010:__flush_tlb_all+0x1b/0x3a [..] Call Trace: phys_pud_init+0x29c/0x2bb kernel_physical_mapping_init+0xfc/0x219 init_memory_mapping+0x1a5/0x3b0 arch_add_memory+0x2c/0x50 devm_memremap_pages+0x3aa/0x610 pmem_attach_disk+0x585/0x700 [nd_pmem] Andy wondered why a path that can sleep was using __flush_tlb_all() [1] and Dave confirmed the expectation for TLB flush is for modifying / invalidating existing PTE entries, but not initial population [2]. Drop the usage of __flush_tlb_all() in phys_{p4d,pud,pmd}_init() on the expectation that this path is only ever populating empty entries for the linear map. Note, at linear map teardown time there is a call to the all-cpu flush_tlb_all() to invalidate the removed mappings. [1]: https://lkml.kernel.org/r/9DFD717D-857D-493D-A606-B635D72BAC21@amacapital.net [2]: https://lkml.kernel.org/r/749919a4-cdb1-48a3-adb4-adb81a5fa0b5@intel.com [ mingo: Minor readability edits. ] Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Reported-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave.hansen@intel.com Fixes: f77084d96355 ("x86/mm/pat: Disable preemption around __flush_tlb_all()") Link: http://lkml.kernel.org/r/154395944713.32119.15611079023837132638.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>