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2018-06-24Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull rseq fixes from Thomas Gleixer: "A pile of rseq related fixups: - Prevent infinite recursion when delivering SIGSEGV - Remove the abort of rseq critical section on fork() as syscalls inside rseq critical sections are explicitely forbidden. So no point in doing the abort on the child. - Align the rseq structure on 32 bytes in the ARM selftest code. - Fix file permissions of the test script" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq: Avoid infinite recursion when delivering SIGSEGV rseq/cleanup: Do not abort rseq c.s. in child on fork() rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes rseq/selftests: Make run_param_test.sh executable
2018-06-24Merge branch 'efi-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Thomas Gleixner: "Two fixlets for the EFI maze: - Properly zero variables to prevent an early boot hang on EFI mixed mode systems - Fix the fallout of merging the 32bit and 64bit variants of EFI PCI related code which ended up chosing the 32bit variant of the actual EFi call invocation which leads to failures on 64bit" * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi/x86: Fix incorrect invocation of PciIo->Attributes() efi/libstub/tpm: Initialize efi_physical_addr_t vars to zero for mixed mode
2018-06-24Merge 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 set of fixes for x86: - Make Xen PV guest deal with speculative store bypass correctly - Address more fallout from the 5-Level pagetable handling. Undo an __initdata annotation to avoid section mismatch and malfunction when post init code would touch the freed variable. - Handle exception fixup in math_error() before calling notify_die(). The reverse call order incorrectly triggers notify_die() listeners for soemthing which is handled correctly at the site which issues the floating point instruction. - Fix an off by one in the LLC topology calculation on AMD - Handle non standard memory block sizes gracefully un UV platforms - Plug a memory leak in the microcode loader - Sanitize the purgatory build magic - Add the x86 specific device tree bindings directory to the x86 MAINTAINER file patterns" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Fix 'no5lvl' handling Revert "x86/mm: Mark __pgtable_l5_enabled __initdata" x86/CPU/AMD: Fix LLC ID bit-shift calculation MAINTAINERS: Add file patterns for x86 device tree bindings x86/microcode/intel: Fix memleak in save_microcode_patch() x86/platform/UV: Add kernel parameter to set memory block size x86/platform/UV: Use new set memory block size function x86/platform/UV: Add adjustable set memory block size function x86/build: Remove unnecessary preparation for purgatory Revert "kexec/purgatory: Add clean-up for purgatory directory" x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths x86: Call fixup_exception() before notify_die() in math_error()
2018-06-24Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti fixes from Thomas Gleixner: "Two small updates for the speculative distractions: - Make it more clear to the compiler that array_index_mask_nospec() is not subject for optimizations. It's not perfect, but ... - Don't report XEN PV guests as vulnerable because their mitigation state depends on the hypervisor. Report unknown and refer to the hypervisor requirement" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec() x86/pti: Don't report XenPV as vulnerable
2018-06-24Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "A set of fixes and updates for the locking code: - Prevent lockdep from updating irq state within its own code and thereby confusing itself. - Buid fix for older GCCs which mistreat anonymous unions - Add a missing lockdep annotation in down_read_non_onwer() which causes up_read_non_owner() to emit a lockdep splat - Remove the custom alpha dec_and_lock() implementation which is incorrect in terms of ordering and use the generic one. The remaining two commits are not strictly fixes. They provide irqsave variants of atomic_dec_and_lock() and refcount_dec_and_lock(). These are required to merge the relevant updates and cleanups into different maintainer trees for 4.19, so routing them into mainline without actual users is the sanest approach. They should have been in -rc1, but last weekend I took the liberty to just avoid computers in order to regain some mental sanity" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/qspinlock: Fix build for anonymous union in older GCC compilers locking/lockdep: Do not record IRQ state within lockdep code locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS locking/refcounts: Implement refcount_dec_and_lock_irqsave() atomic: Add irqsave variant of atomic_dec_and_lock() alpha: Remove custom dec_and_lock() implementation
2018-06-24Merge branch 'ras-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull ras fixes from Thomas Gleixner: "A set of fixes for RAS/MCE: - Improve the error message when the kernel cannot recover from a MCE so the maximum amount of information gets provided. - Individually check MCE recovery features on SkyLake CPUs instead of assuming none when the CAPID0 register does not advertise the general ability for recovery. - Prevent MCE to output inconsistent messages which first show an error location and then claim that the source is unknown. - Prevent overwriting MCi_STATUS in the attempt to gather more information when a fatal MCE has alreay been detected. This leads to empty status values in the printout and failing to react promptly on the fatal event" * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Fix incorrect "Machine check from unknown source" message x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out() x86/mce: Check for alternate indication of machine check recovery on Skylake x86/mce: Improve error message when kernel cannot recover
2018-06-24Merge tag 'mips_fixes_4.18_1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS fixes from Paul Burton: "A few MIPS fixes for 4.18: - a GPIO device name fix for a regression in v4.15-rc1. - an errata workaround for the BCM5300X platform. - a fix to ftrace function graph tracing, broken for a long time with the fix applying cleanly back as far as v3.17. - addition of read barriers to in{b,w,l,q}() functions, matching behavior of other architectures & mirroring the equivalent addition to read{b,w,l,q} in v4.17-rc2. Plus changes to wire up new syscalls introduced in the 4.18 cycle: - Restartable sequences support is added, including MIPS support in the selftests. - io_pgetevents is wired up" * tag 'mips_fixes_4.18_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: MIPS: Wire up io_pgetevents syscall rseq/selftests: Implement MIPS support MIPS: Wire up the restartable sequences (rseq) syscall MIPS: Add syscall detection for restartable sequences MIPS: Add support for restartable sequences MIPS: io: Add barrier after register read in inX() mips: ftrace: fix static function graph tracing MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum MIPS: pb44: Fix i2c-gpio GPIO descriptor table
2018-06-24efi/x86: Fix incorrect invocation of PciIo->Attributes()Ard Biesheuvel
The following commit: 2c3625cb9fa2 ("efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function") ... merged the two versions of __setup_efi_pciXX(), without taking into account that the 32-bit version used a rather dodgy trick to pass an immediate 0 constant as argument for a uint64_t parameter. The issue is caused by the fact that on x86, UEFI protocol method calls are redirected via struct efi_config::call(), which is a variadic function, and so the compiler has to infer the types of the parameters from the arguments rather than from the prototype. As the 32-bit x86 calling convention passes arguments via the stack, passing the unqualified constant 0 twice is the same as passing 0ULL, which is why the 32-bit code in __setup_efi_pci32() contained the following call: status = efi_early->call(pci->attributes, pci, EfiPciIoAttributeOperationGet, 0, 0, &attributes); to invoke this UEFI protocol method: typedef EFI_STATUS (EFIAPI *EFI_PCI_IO_PROTOCOL_ATTRIBUTES) ( IN EFI_PCI_IO_PROTOCOL *This, IN EFI_PCI_IO_PROTOCOL_ATTRIBUTE_OPERATION Operation, IN UINT64 Attributes, OUT UINT64 *Result OPTIONAL ); After the merge, we inadvertently ended up with this version for both 32-bit and 64-bit builds, breaking the latter. So replace the two zeroes with the explicitly typed constant 0ULL, which works as expected on both 32-bit and 64-bit builds. Wilfried tested the 64-bit build, and I checked the generated assembly of a 32-bit build with and without this patch, and they are identical. Reported-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de> Tested-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: hdegoede@redhat.com Cc: linux-efi@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-23ARM: Always build secure_cntvoff.S on ARM V7 to fix shmobile !SMP buildGeert Uytterhoeven
If CONFIG_SMP=n, building a kernel for R-Car Gen2 fails with: arch/arm/mach-shmobile/setup-rcar-gen2.o: In function `rcar_gen2_timer_init': setup-rcar-gen2.c:(.init.text+0x30): undefined reference to `secure_cntvoff_init' Indeed, on R-Car Gen2 SoCs, secure_cntvoff_init() is not only needed for secondary CPUs, but also for the boot CPU. This is most visible on SoCs with Cortex A7 cores (e.g. R-Car E2, cfr. commit 9ce3fa6816c2fb59 ("ARM: shmobile: rcar-gen2: Add CA7 arch_timer initialization for r8a7794")), but Cortex A15 is affected, too. Fix this by always providing secure_cntvoff_init() when building for ARM V7. Reported-by: Arnd Bergmann <arnd@arndb.de> Fixes: 7c607944bc657616 ("ARM: smp: Add initialization of CNTVOFF") Fixes: cad160ed0a94927e ("ARM: shmobile: Convert file to use cntvoff") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-24Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: - Fix use after free in chtls - Fix RBP breakage in sha3 - Fix use after free in hwrng_unregister - Fix overread in morus640 - Move sleep out of kernel_neon in arm64/aes-blk * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: hwrng: core - Always drop the RNG in hwrng_unregister() crypto: morus640 - Fix out-of-bounds access crypto: don't optimize keccakf() crypto: arm64/aes-blk - fix and move skcipher_walk_done out of kernel_neon_begin, _end crypto: chtls - use after free in chtls_pt_recvmsg()
2018-06-23Merge tag 'socfpga_nand_fix_v4.17' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux into fixes ARM: dts: socfpga: fix NAND support - NAND should be using nand_x_clk, not nand_clk - fix NAND node compatible for Cyclone5 and Arria10 * tag 'socfpga_nand_fix_v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: ARM: dts: socfpga: Fix NAND controller node compatible for Arria10 ARM: dts: socfpga: Fix NAND controller node compatible ARM: dts: socfpga: Fix NAND controller clock supply Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23ARM: multi_v7_defconfig: renormalize based on recent additionsOlof Johansson
The defconfig has drifted over time, as Kconfig entries have changed order or default values. Several maintainers ended up running 'savedefconfig' themselves which caused a cascade of conflicts. Let's do it once and for all in our tree before -rc2 instead. Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23arm64: defconfig: renormalize based on recent additionsOlof Johansson
The defconfig has drifted over time, as Kconfig entries have changed order or default values. Several maintainers ended up running 'savedefconfig' themselves which caused a cascade of conflicts. Let's do it once and for all in our tree before -rc2 instead. Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'qcom-fixes-for-4.18-rc1' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux into fixes Qualcomm Fixes for v4.18-rc1 * Fix coresight graph on msm8916 * Disable uart0 on db820c by default * tag 'qcom-fixes-for-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux: arm64: dts: msm8916: fix Coresight ETF graph connections arm64: dts: apq8096-db820c: disable uart0 by default Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'arm-soc/for-4.18/devicetree-arm64-fixes' of ↵Olof Johansson
https://github.com/Broadcom/stblinux into fixes This pull request contains Broadcom ARM64-based SoCs Device Tree fixes for 4.18, please pull the following: - Scott fixes both the bcm958742k and bcm958742t reference boards to have the correct eMMC voltage specified - Ray fixes the I2C and PCIe Device Tree nodes interrupt specifiers for Northstar 2 and Stingray SoCs. * tag 'arm-soc/for-4.18/devicetree-arm64-fixes' of https://github.com/Broadcom/stblinux: arm64: dts: Stingray: Fix I2C controller interrupt type arm64: dts: ns2: Fix PCIe controller interrupt type arm64: dts: ns2: Fix I2C controller interrupt type arm64: dts: specify 1.8V EMMC capabilities for bcm958742t arm64: dts: specify 1.8V EMMC capabilities for bcm958742k Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'arm-soc/for-4.18/devicetree-fixes' of ↵Olof Johansson
https://github.com/Broadcom/stblinux into fixes This pull request contains Broadcom ARM-based SoCs Device Tree fixes for 4.18, please pull the following: - Ray fixes the I2C and PCIe interrupt types for the Cygnus SoC - Florian fixes the I2C and PCIe interrupts for the Northstar (BCM5301x), Northstar Plus and Hurricane 2 SoCs * tag 'arm-soc/for-4.18/devicetree-fixes' of https://github.com/Broadcom/stblinux: ARM: dts: Cygnus: Fix PCIe controller interrupt type ARM: dts: Cygnus: Fix I2C controller interrupt type ARM: dts: BCM5301x: Fix i2c controller interrupt type ARM: dts: HR2: Fix interrupt types for i2c and PCIe ARM: dts: NSP: Fix PCIe controllers interrupt types ARM: dts: NSP: Fix i2c controller interrupt type Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'imx-fixes-4.18' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes i.MX fixes for 4.18: - Fix i.MX6SX PCIe MSI interrupt number, so that MSI IRQs can be properly propagated to the upstream interrupt controller. - Fix GPCv2 MIPI/PCIe/USB_HSIC's PGC offset. The values in Reference Manual are incorrect. - Correct SDMA setting for i.MX6Q SPI5 device to fix the issue, that the SPI controller RX FIFO was not empty after a DMA transfer, and the driver gets stuck in the next PIO transfer when reading one word more than expected. * tag 'imx-fixes-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux: ARM: dts: imx6sx: fix irq for pcie bridge soc: imx: gpcv2: correct PGC offset ARM: dts: imx6q: Use correct SDMA script for SPI5 core Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'mvebu-fixes-4.17-2' of git://git.infradead.org/linux-mvebu into fixesOlof Johansson
mvebu fixes for 4.17 (part 2) - Use correct size for ICU nodes (irq controller) on Armada 7K/8K - Fix "#cooling-cells" property's name on Synology DS116 (Armada 385) * tag 'mvebu-fixes-4.17-2' of git://git.infradead.org/linux-mvebu: arm: dts: armada: Fix "#cooling-cells" property's name arm64: dts: marvell: fix CP110 ICU node size Signed-off-by: Olof Johansson <olof@lixom.net>
2018-06-23Merge tag 'powerpc-4.18-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - a fix for hugetlb with 4K pages, broken by our recent changes for split PMD PTL. - set the correct assembler machine type on e500mc, needed since binutils 2.26 introduced two forms for the "wait" instruction. - a fix for potential missed TLB flushes with MADV_[FREE|DONTNEED] etc. and THP on Power9 Radix. - three fixes to try and make our panic handling more robust by hard disabling interrupts, and not marking stopped CPUs as offline because they haven't been properly offlined. - three other minor fixes. Thanks to: Aneesh Kumar K.V, Michael Jeanson, Nicholas Piggin. * tag 'powerpc-4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/mm/hash/4k: Free hugetlb page table caches correctly. powerpc/64s/radix: Fix radix_kvm_prefetch_workaround paca access of not possible CPU powerpc/64s: Fix build failures with CONFIG_NMI_IPI=n powerpc/64: hard disable irqs on the panic()ing CPU powerpc: smp_send_stop do not offline stopped CPUs powerpc/64: hard disable irqs in panic_smp_self_stop powerpc/64s: Fix DT CPU features Power9 DD2.1 logic powerpc/64s/radix: Fix MADV_[FREE|DONTNEED] TLB flush miss problem with THP powerpc/e500mc: Set assembler machine type to e500mc
2018-06-23Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: - clear buffers allocated with FORCE_CONTIGUOUS explicitly until the CMA code honours __GFP_ZERO - notrace annotation for secondary_start_kernel() - use early_param() instead of __setup() for "kpti=" as it is needed for the cpufeature callback remapping swapper to non-global mappings - ensure writes to swapper are ordered wrt subsequent cache maintenance in the kpti non-global remapping code * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mm: Ensure writes to swapper are ordered wrt subsequent cache maintenance arm64: kpti: Use early_param for kpti= command-line option arm64: make secondary_start_kernel() notrace arm64: dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag
2018-06-23Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Radim Krčmář: "ARM: - Lazy FPSIMD switching fixes - Really disable compat ioctls on architectures that don't want it - Disable compat on arm64 (it was never implemented...) - Rely on architectural requirements for GICV on GICv3 - Detect bad alignments in unmap_stage2_range x86: - Add nested VM entry checks to avoid broken error recovery path - Minor documentation fix" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: fix KVM_CAP_HYPERV_TLBFLUSH paragraph number kvm: vmx: Nested VM-entry prereqs for event inj. KVM: arm64: Prevent KVM_COMPAT from being selected KVM: Enforce error in ioctl for compat tasks when !KVM_COMPAT KVM: arm/arm64: add WARN_ON if size is not PAGE_SIZE aligned in unmap_stage2_range KVM: arm64: Avoid mistaken attempts to save SVE state for vcpus KVM: arm64/sve: Fix SVE trap restoration for non-current tasks KVM: arm64: Don't mask softirq with IRQs disabled in vcpu_put() arm64: Introduce sysreg_clear_set() KVM: arm/arm64: Drop resource size check for GICV window
2018-06-23Merge tag 'for-linus-4.18-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "This contains the following fixes/cleanups: - the removal of a BUG_ON() which wasn't necessary and which could trigger now due to a recent change - a correction of a long standing bug happening very rarely in Xen dom0 when a hypercall buffer from user land was not accessible by the hypervisor for very short periods of time due to e.g. page migration or compaction - usage of EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL() in a Xen-related driver (no breakage possible as using those symbols without others already exported via EXPORT-SYMBOL_GPL() wouldn't make any sense) - a simplification for Xen PVH or Xen ARM guests - some additional error handling for callers of xenbus_printf()" * tag 'for-linus-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Remove unnecessary BUG_ON from __unbind_from_irq() xen: add new hypercall buffer mapping device xen/scsiback: add error handling for xenbus_printf scsi: xen-scsifront: add error handling for xenbus_printf xen/grant-table: Export gnttab_{alloc|free}_pages as GPL xen: add error handling for xenbus_printf xen: share start flags between PV and PVH
2018-06-23x86/mm: Fix 'no5lvl' handlingKirill A. Shutemov
early_identify_cpu() has to use early version of pgtable_l5_enabled() that doesn't rely on cpu_feature_enabled(). Defining USE_EARLY_PGTABLE_L5 before all includes does the trick. I lost the define in one of reworks of the original patch. Fixes: 372fddf70904 ("x86/mm: Introduce the 'no5lvl' kernel parameter") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/20180622220841.54135-3-kirill.shutemov@linux.intel.com
2018-06-23Revert "x86/mm: Mark __pgtable_l5_enabled __initdata"Kirill A. Shutemov
This reverts commit e4e961e36f063484c48bed919013c106d178995d. We need to use early version of pgtable_l5_enabled() in early_identify_cpu() as this code runs before cpu_feature_enabled() is usable. But it leads to section mismatch: cpu_init() load_mm_ldt() ldt_slot_va() LDT_BASE_ADDR LDT_PGD_ENTRY pgtable_l5_enabled() __pgtable_l5_enabled __pgtable_l5_enabled marked as __initdata, but cpu_init() is not __init. It's fixable: early code can be isolated into a separate translation unit, but such change collides with other work in the area. That's too much hassle to save 4 bytes of memory. Return __pgtable_l5_enabled back to be __ro_after_init. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/20180622220841.54135-2-kirill.shutemov@linux.intel.com
2018-06-23powerpc: Wire up io_pgeteventsBreno Leitao
Wire up io_pgetevents system call on powerpc. io_pgetevents is a new syscall to read asynchronous I/O events from the completion queue. Tested with libaio branch aio-poll[1] and the io_pgetevents test (#22) passed on both ppc64 LE and BE modes. [1] https://pagure.io/libaio/branch/aio-poll CC: Christoph Hellwig <hch@lst.de> Signed-off-by: Breno Leitao <leitao@debian.org> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-23arm64: dts: msm8916: fix Coresight ETF graph connectionsRob Herring
The ETF input should be connected to the funnel output, and the ETF output should be connected to the replicator input. The labels are wrong and these got swapped: Warning (graph_endpoint): /soc/funnel@821000/ports/port@8/endpoint: graph connection to node '/soc/etf@825000/ports/port@1/endpoint' is not bidirectional Warning (graph_endpoint): /soc/replicator@824000/ports/port@2/endpoint: graph connection to node '/soc/etf@825000/ports/port@0/endpoint' is not bidirectional Fixes: 7c10da373698 ("arm64: dts: qcom: Add msm8916 CoreSight components") Cc: Ivan T. Ivanov <ivan.ivanov@linaro.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: linux-arm-msm@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-06-22arm64: dts: apq8096-db820c: disable uart0 by defaultSrinivas Kandagatla
Access to UART0 is disabled by bootloaders. By leaving it enabled by default would reboot the board. Disable this for now, this would alteast give a board which boots. Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-06-22x86/CPU/AMD: Fix LLC ID bit-shift calculationSuravee Suthikulpanit
The current logic incorrectly calculates the LLC ID from the APIC ID. Unless specified otherwise, the LLC ID should be calculated by removing the Core and Thread ID bits from the least significant end of the APIC ID. For more info, see "ApicId Enumeration Requirements" in any Fam17h PPR document. [ bp: Improve commit message. ] Fixes: 68091ee7ac3c ("Calculate last level cache ID from number of sharing threads") Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1528915390-30533-1-git-send-email-suravee.suthikulpanit@amd.com
2018-06-22Merge branch 'linus' into x86/urgentThomas Gleixner
Required to queue a dependent fix.
2018-06-22rseq: Avoid infinite recursion when delivering SIGSEGVWill Deacon
When delivering a signal to a task that is using rseq, we call into __rseq_handle_notify_resume() so that the registers pushed in the sigframe are updated to reflect the state of the restartable sequence (for example, ensuring that the signal returns to the abort handler if necessary). However, if the rseq management fails due to an unrecoverable fault when accessing userspace or certain combinations of RSEQ_CS_* flags, then we will attempt to deliver a SIGSEGV. This has the potential for infinite recursion if the rseq code continuously fails on signal delivery. Avoid this problem by using force_sigsegv() instead of force_sig(), which is explicitly designed to reset the SEGV handler to SIG_DFL in the case of a recursive fault. In doing so, remove rseq_signal_deliver() from the internal rseq API and have an optional struct ksignal * parameter to rseq_handle_notify_resume() instead. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: peterz@infradead.org Cc: paulmck@linux.vnet.ibm.com Cc: boqun.feng@gmail.com Link: https://lkml.kernel.org/r/1529664307-983-1-git-send-email-will.deacon@arm.com
2018-06-22arm64: mm: Ensure writes to swapper are ordered wrt subsequent cache maintenanceWill Deacon
When rewriting swapper using nG mappings, we must performance cache maintenance around each page table access in order to avoid coherency problems with the host's cacheable alias under KVM. To ensure correct ordering of the maintenance with respect to Device memory accesses made with the Stage-1 MMU disabled, DMBs need to be added between the maintenance and the corresponding memory access. This patch adds a missing DMB between writing a new page table entry and performing a clean+invalidate on the same line. Fixes: f992b4dfd58b ("arm64: kpti: Add ->enable callback to remap swapper using nG mappings") Cc: <stable@vger.kernel.org> # 4.16.x- Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-22arm64: kpti: Use early_param for kpti= command-line optionWill Deacon
We inspect __kpti_forced early on as part of the cpufeature enable callback which remaps the swapper page table using non-global entries. Ensure that __kpti_forced has been updated to reflect the kpti= command-line option before we start using it. Fixes: ea1e3de85e94 ("arm64: entry: Add fake CPU feature for unmapping the kernel at EL0") Cc: <stable@vger.kernel.org> # 4.16.x- Reported-by: Wei Xu <xuwei5@hisilicon.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-06-22kvm: vmx: Nested VM-entry prereqs for event inj.Marc Orr
This patch extends the checks done prior to a nested VM entry. Specifically, it extends the check_vmentry_prereqs function with checks for fields relevant to the VM-entry event injection information, as described in the Intel SDM, volume 3. This patch is motivated by a syzkaller bug, where a bad VM-entry interruption information field is generated in the VMCS02, which causes the nested VM launch to fail. Then, KVM fails to resume L1. While KVM should be improved to correctly resume L1 execution after a failed nested launch, this change is justified because the existing code to resume L1 is flaky/ad-hoc and the test coverage for resuming L1 is sparse. Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Marc Orr <marcorr@google.com> [Removed comment whose parts were describing previous revisions and the rest was obvious from function/variable naming. - Radim] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-06-22x86/microcode/intel: Fix memleak in save_microcode_patch()Zhenzhong Duan
Free useless ucode_patch entry when it's replaced. [ bp: Drop the memfree_patch() two-liner. ] Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Srinivas REDDY Eeda <srinivas.eeda@oracle.com> Link: http://lkml.kernel.org/r/888102f0-fd22-459d-b090-a1bd8a00cb2b@default
2018-06-22x86/mce: Fix incorrect "Machine check from unknown source" messageTony Luck
Some injection testing resulted in the following console log: mce: [Hardware Error]: CPU 22: Machine Check Exception: f Bank 1: bd80000000100134 mce: [Hardware Error]: RIP 10:<ffffffffc05292dd> {pmem_do_bvec+0x11d/0x330 [nd_pmem]} mce: [Hardware Error]: TSC c51a63035d52 ADDR 3234bc4000 MISC 88 mce: [Hardware Error]: PROCESSOR 0:50654 TIME 1526502199 SOCKET 0 APIC 38 microcode 2000043 mce: [Hardware Error]: Run the above through 'mcelog --ascii' Kernel panic - not syncing: Machine check from unknown source This confused everybody because the first line quite clearly shows that we found a logged error in "Bank 1", while the last line says "unknown source". The problem is that the Linux code doesn't do the right thing for a local machine check that results in a fatal error. It turns out that we know very early in the handler whether the machine check is fatal. The call to mce_no_way_out() has checked all the banks for the CPU that took the local machine check. If it says we must crash, we can do so right away with the right messages. We do scan all the banks again. This means that we might initially not see a problem, but during the second scan find something fatal. If this happens we print a slightly different message (so I can see if it actually every happens). [ bp: Remove unneeded severity assignment. ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org # 4.2 Link: http://lkml.kernel.org/r/52e049a497e86fd0b71c529651def8871c804df0.1527283897.git.tony.luck@intel.com
2018-06-22x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out()Borislav Petkov
mce_no_way_out() does a quick check during #MC to see whether some of the MCEs logged would require the kernel to panic immediately. And it passes a struct mce where MCi_STATUS gets written. However, after having saved a valid status value, the next iteration of the loop which goes over the MCA banks on the CPU, overwrites the valid status value because we're using struct mce as storage instead of a temporary variable. Which leads to MCE records with an empty status value: mce: [Hardware Error]: CPU 0: Machine Check Exception: 6 Bank 0: 0000000000000000 mce: [Hardware Error]: RIP 10:<ffffffffbd42fbd7> {trigger_mce+0x7/0x10} In order to prevent the loss of the status register value, return immediately when severity is a panic one so that we can panic immediately with the first fatal MCE logged. This is also the intention of this function and not to noodle over the banks while a fatal MCE is already logged. Tony: read the rest of the MCA bank to populate the struct mce fully. Suggested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20180622095428.626-8-bp@alien8.de
2018-06-21uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn()Oleg Nesterov
insn_get_length() has the side-effect of processing the entire instruction but only if it was decoded successfully, otherwise insn_complete() can fail and in this case we need to just return an error without warning. Reported-by: syzbot+30d675e3ca03c1c351e7@syzkaller.appspotmail.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: syzkaller-bugs@googlegroups.com Link: https://lkml.kernel.org/lkml/20180518162739.GA5559@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/platform/UV: Add kernel parameter to set memory block sizemike.travis@hpe.com
Add a kernel parameter that allows setting UV memory block size. This is to provide an adjustment for new forms of PMEM and other DIMM memory that might require alignment restrictions other than scanning the global address table for the required minimum alignment. The value set will be further adjusted by both the GAM range table scan as well as restrictions imposed by set_memory_block_size_order(). Signed-off-by: Mike Travis <mike.travis@hpe.com> Reviewed-by: Andrew Banman <andrew.banman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Cc: jgross@suse.com Cc: kirill.shutemov@linux.intel.com Cc: mhocko@suse.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/lkml/20180524201711.854849120@stormcage.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/platform/UV: Use new set memory block size functionmike.travis@hpe.com
Add a call to the new function to "adjust" the current fixed UV memory block size of 2GB so it can be changed to a different physical boundary. This accommodates changes in the Intel BIOS, and therefore UV BIOS, which now can align boundaries different than the previous UV standard of 2GB. It also flags any UV Global Address boundaries from BIOS that cause a change in the mem block size (boundary). The current boundary of 2GB has been used on UV since the first system release in 2009 with Linux 2.6 and has worked fine. But the new NVDIMM persistent memory modules (PMEM), along with the Intel BIOS changes to support these modules caused the memory block size boundary to be set to a lower limit. Intel only guarantees that this minimum boundary at 64MB though the current Linux limit is 128MB. Note that the default remains 2GB if no changes occur. Signed-off-by: Mike Travis <mike.travis@hpe.com> Reviewed-by: Andrew Banman <andrew.banman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Cc: jgross@suse.com Cc: kirill.shutemov@linux.intel.com Cc: mhocko@suse.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/lkml/20180524201711.732785782@stormcage.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/platform/UV: Add adjustable set memory block size functionmike.travis@hpe.com
Add a new function to "adjust" the current fixed UV memory block size of 2GB so it can be changed to a different physical boundary. This is out of necessity so arch dependent code can accommodate specific BIOS requirements which can align these new PMEM modules at less than the default boundaries. A "set order" type of function was used to insure that the memory block size will be a power of two value without requiring a validity check. 64GB was chosen as the upper limit for memory block size values to accommodate upcoming 4PB systems which have 6 more bits of physical address space (46 becoming 52). Signed-off-by: Mike Travis <mike.travis@hpe.com> Reviewed-by: Andrew Banman <andrew.banman@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Cc: jgross@suse.com Cc: kirill.shutemov@linux.intel.com Cc: mhocko@suse.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/lkml/20180524201711.609546602@stormcage.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec()Dan Williams
Mark Rutland noticed that GCC optimization passes have the potential to elide necessary invocations of the array_index_mask_nospec() instruction sequence, so mark the asm() volatile. Mark explains: "The volatile will inhibit *some* cases where the compiler could lift the array_index_nospec() call out of a branch, e.g. where there are multiple invocations of array_index_nospec() with the same arguments: if (idx < foo) { idx1 = array_idx_nospec(idx, foo) do_something(idx1); } < some other code > if (idx < foo) { idx2 = array_idx_nospec(idx, foo); do_something_else(idx2); } ... since the compiler can determine that the two invocations yield the same result, and reuse the first result (likely the same register as idx was in originally) for the second branch, effectively re-writing the above as: if (idx < foo) { idx = array_idx_nospec(idx, foo); do_something(idx); } < some other code > if (idx < foo) { do_something_else(idx); } ... if we don't take the first branch, then speculatively take the second, we lose the nospec protection. There's more info on volatile asm in the GCC docs: https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Volatile " Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: babdde2698d4 ("x86: Implement array_index_mask_nospec") Link: https://lkml.kernel.org/lkml/152838798950.14521.4893346294059739135.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/pti: Don't report XenPV as vulnerableJiri Kosina
Xen PV domain kernel is not by design affected by meltdown as it's enforcing split CR3 itself. Let's not report such systems as "Vulnerable" in sysfs (we're also already forcing PTI to off in X86_HYPER_XEN_PV cases); the security of the system ultimately depends on presence of mitigation in the Hypervisor, which can't be easily detected from DomU; let's report that. Reported-and-tested-by: Mike Latimer <mlatimer@suse.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Juergen Gross <jgross@suse.com> Cc: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1806180959080.6203@cbobk.fhfr.pm [ Merge the user-visible string into a single line. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21microblaze: consolidate GPIO reset handlingRob Herring
Now that platform.c only has the GPIO reset handling left, move the initcall to reset.c and remove platform.c. Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2018-06-21microblaze: remove unecessary of_platform_bus_probe callRob Herring
The call to of_platform_bus_probe has no effect because the DT core already probes default buses like "simple-bus" before this call. Michal Simek said 'xlnx,compound' hasn't been used in a long time, so that match entry isn't needed. Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2018-06-21microblaze: Add new syscalls io_pgetevents and rseqMichal Simek
Wire up new syscalls io_pgetevents and rseq. Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2018-06-21x86/build: Remove unnecessary preparation for purgatoryMasahiro Yamada
kexec-purgatory.c is properly generated when Kbuild descend into the arch/x86/purgatory/. Thus the 'archprepare' target is redundant. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/1529401422-28838-3-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21Revert "kexec/purgatory: Add clean-up for purgatory directory"Masahiro Yamada
Reverts the following commit: b0108f9e93d0 ("kexec: purgatory: add clean-up for purgatory directory") ... which incorrectly stated that the kexec-purgatory.c and purgatory.ro files were not removed after 'make mrproper'. In fact, they are. You can confirm it after reverting it. $ make mrproper $ touch arch/x86/purgatory/kexec-purgatory.c $ touch arch/x86/purgatory/purgatory.ro $ make mrproper CLEAN arch/x86/purgatory $ ls arch/x86/purgatory/ entry64.S Makefile purgatory.c setup-x86_64.S stack.S string.c This is obvious from the build system point of view. arch/x86/Makefile adds 'arch/x86' to core-y. Hence 'make clean' descends like this: arch/x86/Kbuild -> arch/x86/purgatory/Makefile Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/1529401422-28838-2-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21x86/xen: Add call of speculative_store_bypass_ht_init() to PV pathsJuergen Gross
Commit: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD") ... added speculative_store_bypass_ht_init() to the per-CPU initialization sequence. speculative_store_bypass_ht_init() needs to be called on each CPU for PV guests, too. Reported-by: Brian Woods <brian.woods@amd.com> Tested-by: Brian Woods <brian.woods@amd.com> Signed-off-by: Juergen Gross <jgross@suse.com> Cc: <stable@vger.kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: xen-devel@lists.xenproject.org Fixes: 1f50ddb4f4189243c05926b842dc1a0332195f31 ("x86/speculation: Handle HT correctly on AMD") Link: https://lore.kernel.org/lkml/20180621084331.21228-1-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21KVM: arm64: Avoid mistaken attempts to save SVE state for vcpusDave Martin
Commit e6b673b ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") uses fpsimd_save() to save the FPSIMD state for a vcpu when scheduling the vcpu out. However, currently current's value of TIF_SVE is restored before calling fpsimd_save() which means that fpsimd_save() may erroneously attempt to save SVE state from the vcpu. This enables current's vector state to be polluted with guest data. current->thread.sve_state may be unallocated or not large enough, so this can also trigger a NULL dereference or buffer overrun. Instead of this, TIF_SVE should be configured properly for the guest when calling fpsimd_save() with the vcpu context loaded. This patch ensures this by delaying restoration of current's TIF_SVE until after the call to fpsimd_save(). Fixes: e6b673b741ea ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-06-21KVM: arm64/sve: Fix SVE trap restoration for non-current tasksDave Martin
Commit e6b673b ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") attempts to restore the configuration of userspace SVE trapping via a call to fpsimd_bind_task_to_cpu(), but the logic for determining when to do this is not correct. The patch makes the errnoenous assumption that the only task that may try to enter userspace with the currently loaded FPSIMD/SVE register content is current. This may not be the case however: if some other user task T is scheduled on the CPU during the execution of the KVM run loop, and the vcpu does not try to use the registers in the meantime, then T's state may be left there intact. If T happens to be the next task to enter userspace on this CPU then the hooks for reloading the register state and configuring traps will be skipped. (Also, current never has SVE state at this point anyway and should always have the trap enabled, as a side-effect of the ioctl() syscall needed to reach the KVM run loop in the first place.) This patch instead restores the state of the EL0 trap from the state observed at the most recent vcpu_load(), ensuring that the trap is set correctly for the loaded context (if any). Fixes: e6b673b741ea ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>