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2020-03-20Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: - Fix panic() when it occurs during secondary CPU startup - Fix "kpti=off" when KASLR is enabled - Fix howler in compat syscall table for vDSO clock_getres() fallback * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: compat: Fix syscall number of compat_clock_getres arm64: kpti: Fix "kpti=off" when KASLR is enabled arm64: smp: fix crash_smp_send_stop() behaviour arm64: smp: fix smp_send_stop() behaviour
2020-03-19arm64: compat: Fix syscall number of compat_clock_getresVincenzo Frascino
The syscall number of compat_clock_getres was erroneously set to 247 (__NR_io_cancel!) instead of 264. This causes the vDSO fallback of clock_getres() to land on the wrong syscall for compat tasks. Fix the numbering. Cc: <stable@vger.kernel.org> Fixes: 53c489e1dfeb6 ("arm64: compat: Add missing syscall numbers") Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2020-03-19arm64: kpti: Fix "kpti=off" when KASLR is enabledWill Deacon
Enabling KASLR forces the use of non-global page-table entries for kernel mappings, as this is a decision that we have to make very early on before mapping the kernel proper. When used in conjunction with the "kpti=off" command-line option, it is possible to use non-global kernel mappings but with the kpti trampoline disabled. Since commit 09e3c22a86f6 ("arm64: Use a variable to store non-global mappings decision"), arm64_kernel_unmapped_at_el0() reflects only the use of non-global mappings and does not take into account whether the kpti trampoline is enabled. This breaks context switching of the TPIDRRO_EL0 register for 64-bit tasks, where the clearing of the register is deferred to the ret-to-user code, but it also breaks the ARM SPE PMU driver which helpfully recommends passing "kpti=off" on the command line! Report whether or not KPTI is actually enabled in arm64_kernel_unmapped_at_el0() and check the 'arm64_use_ng_mappings' global variable directly when determining the protection flags for kernel mappings. Cc: Mark Brown <broonie@kernel.org> Reported-by: Hongbo Yao <yaohongbo@huawei.com> Tested-by: Hongbo Yao <yaohongbo@huawei.com> Fixes: 09e3c22a86f6 ("arm64: Use a variable to store non-global mappings decision") Signed-off-by: Will Deacon <will@kernel.org>
2020-03-01Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "More bugfixes, including a few remaining "make W=1" issues such as too large frame sizes on some configurations. On the ARM side, the compiler was messing up shadow stacks between EL1 and EL2 code, which is easily fixed with __always_inline" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: VMX: check descriptor table exits on instruction emulation kvm: x86: Limit the number of "kvm: disabled by bios" messages KVM: x86: avoid useless copy of cpufreq policy KVM: allow disabling -Werror KVM: x86: allow compiling as non-module with W=1 KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis KVM: Introduce pv check helpers KVM: let declaration of kvm_get_running_vcpus match implementation KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter arm64: Ask the compiler to __always_inline functions used by KVM at HYP KVM: arm64: Define our own swab32() to avoid a uapi static inline KVM: arm64: Ask the compiler to __always_inline functions used at HYP kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe() KVM: arm/arm64: Fix up includes for trace.h
2020-02-28Merge tag 'kvmarm-fixes-5.6-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm fixes for 5.6, take #1 - Fix compilation on 32bit - Move VHE guest entry/exit into the VHE-specific entry code - Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
2020-02-22arm64: Ask the compiler to __always_inline functions used by KVM at HYPJames Morse
KVM uses some of the static-inline helpers like icache_is_vipt() from its HYP code. This assumes the function is inlined so that the code is mapped to EL2. The compiler may decide not to inline these, and the out-of-line version may not be in the __hyp_text section. Add the additional __always_ hint to these static-inlines that are used by KVM. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20200220165839.256881-4-james.morse@arm.com
2020-02-22KVM: arm64: Define our own swab32() to avoid a uapi static inlineJames Morse
KVM uses swab32() when mediating GIC MMIO accesses if the GICV is badly aligned, and the host and guest differ in endianness. arm64 doesn't provide a __arch_swab32(), so __fswab32() is always backed by the macro implementation that the compiler reduces to a single instruction. But the static-inline causes problems for KVM if the compiler chooses not to inline this function, it may not be located in the __hyp_text where __vgic_v2_perform_cpuif_access() needs it. Create our own __kvm_swab32() macro that calls ___constant_swab32() directly. This way we know it will always be inlined. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200220165839.256881-3-james.morse@arm.com
2020-02-22KVM: arm64: Ask the compiler to __always_inline functions used at HYPJames Morse
On non VHE CPUs, KVM's __hyp_text contains code run at EL2 while the rest of the kernel runs at EL1. This code lives in its own section with start and end markers so we can map it to EL2. The compiler may decide not to inline static-inline functions from the header file. It may also decide not to put these out-of-line functions in the same section, meaning they aren't mapped when called at EL2. Clang-9 does exactly this with __kern_hyp_va() and a few others when x18 is reserved for the shadow call stack. Add the additional __always_ hint to all the static-inlines that are called from a hyp file. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200220165839.256881-2-james.morse@arm.com ---- kvm_get_hyp_vector() pulls in all the regular per-cpu accessors and this_cpu_has_cap(), fortunately its only called for VHE.
2020-02-19arm64: memory: Add missing brackets to untagged_addr() macroWill Deacon
Add brackets around the evaluation of the 'addr' parameter to the untagged_addr() macro so that the cast to 'u64' applies to the result of the expression. Cc: <stable@vger.kernel.org> Fixes: 597399d0cb91 ("arm64: tags: Preserve tags for addresses translated via TTBR1") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-02-18arm64: lse: Fix LSE atomics with LLVMVincenzo Frascino
Commit e0d5896bd356 ("arm64: lse: fix LSE atomics with LLVM's integrated assembler") broke the build when clang is used in connjunction with the binutils assembler ("-no-integrated-as"). This happens because __LSE_PREAMBLE is defined as ".arch armv8-a+lse", which overrides the version of the CPU architecture passed via the "-march" paramter to gas: $ aarch64-none-linux-gnu-as -EL -I ./arch/arm64/include -I ./arch/arm64/include/generated -I ./include -I ./include -I ./arch/arm64/include/uapi -I ./arch/arm64/include/generated/uapi -I ./include/uapi -I ./include/generated/uapi -I ./init -I ./init -march=armv8.3-a -o init/do_mounts.o /tmp/do_mounts-d7992a.s /tmp/do_mounts-d7992a.s: Assembler messages: /tmp/do_mounts-d7992a.s:1959: Error: selected processor does not support `autiasp' /tmp/do_mounts-d7992a.s:2021: Error: selected processor does not support `paciasp' /tmp/do_mounts-d7992a.s:2157: Error: selected processor does not support `autiasp' /tmp/do_mounts-d7992a.s:2175: Error: selected processor does not support `paciasp' /tmp/do_mounts-d7992a.s:2494: Error: selected processor does not support `autiasp' Fix the issue by replacing ".arch armv8-a+lse" with ".arch_extension lse". Sami confirms that the clang integrated assembler does now support the '.arch_extension' directive, so this change will be fine even for LTO builds in future. Fixes: e0d5896bd356cd ("arm64: lse: fix LSE atomics with LLVM's integrated assembler") Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reported-by: Amit Kachhap <Amit.Kachhap@arm.com> Tested-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2020-02-17kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()Mark Rutland
With VHE, running a vCPU always requires the sequence: 1. kvm_arm_vhe_guest_enter(); 2. kvm_vcpu_run_vhe(); 3. kvm_arm_vhe_guest_exit() ... and as we invoke this from the shared arm/arm64 KVM code, 32-bit arm has to provide stubs for all three functions. To simplify the common code, and make it easier to make further modifications to the arm64-specific portions in the near future, let's fold kvm_arm_vhe_guest_enter() and kvm_arm_vhe_guest_exit() into kvm_vcpu_run_vhe(). The 32-bit stubs for kvm_arm_vhe_guest_enter() and kvm_arm_vhe_guest_exit() are removed, as they are no longer used. The 32-bit stub for kvm_vcpu_run_vhe() is left as-is. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200210114757.2889-1-mark.rutland@arm.com
2020-02-10arm64/spinlock: fix a -Wunused-function warningQian Cai
The commit f5bfdc8e3947 ("locking/osq: Use optimized spinning loop for arm64") introduced a warning from Clang because vcpu_is_preempted() is compiled away, kernel/locking/osq_lock.c:25:19: warning: unused function 'node_cpu' [-Wunused-function] static inline int node_cpu(struct optimistic_spin_node *node) ^ 1 warning generated. Fix it by converting vcpu_is_preempted() to a static inline function. Fixes: f5bfdc8e3947 ("locking/osq: Use optimized spinning loop for arm64") Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Will Deacon <will@kernel.org>
2020-02-10arm64: Drop do_el0_ia_bp_hardening() & do_sp_pc_abort() declarationsAnshuman Khandual
There is a redundant do_sp_pc_abort() declaration in exceptions.h which can be removed. Also do_el0_ia_bp_hardening() as been already been dropped with the commit bfe298745afc ("arm64: entry-common: don't touch daif before bp-hardening") and hence does not need a declaration any more. This should not introduce any functional change. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2020-02-08Merge tag 'irqchip-fixes-5.6-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes for 5.6, take #1 from Marc Zyngier: - Guarantee allocation of L2 vPE table for GICv4.1 - Fix GICv4.1 VPROPBASER programming - Numerous GICv4.1 tidy ups - Fix disabled GICv3 redistributor provisioning with ACPI - KConfig cleanup for C-SKY
2020-02-08irqchip/gic-v3-its: Rename VPENDBASER/VPROPBASER accessorsZenghui Yu
V{PEND,PROP}BASER registers are actually located in VLPI_base frame of the *redistributor*. Rename their accessors to reflect this fact. No functional changes. Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200206075711.1275-7-yuzenghui@huawei.com
2020-02-04Merge tag 'microblaze-v5.6-rc1' of git://git.monstr.eu/linux-2.6-microblazeLinus Torvalds
Pull Microblaze update from Michal Simek: - enable CMA - add support for MB v11 - defconfig updates - minor fixes * tag 'microblaze-v5.6-rc1' of git://git.monstr.eu/linux-2.6-microblaze: microblaze: Add ID for Microblaze v11 microblaze: Prevent the overflow of the start microblaze: Wire CMA allocator asm-generic: Make dma-contiguous.h a mandatory include/asm header microblaze: Sync defconfig with latest Kconfig layout microblaze: defconfig: Disable EXT2 driver and Enable EXT3 & EXT4 drivers microblaze: Align comments with register usage
2020-02-04asm-generic: Make dma-contiguous.h a mandatory include/asm headerMichal Simek
dma-continuguous.h is generic for all architectures except arm32 which has its own version. Similar change was done for msi.h by commit a1b39bae16a6 ("asm-generic: Make msi.h a mandatory include/asm header") Suggested-by: Christoph Hellwig <hch@infradead.org> Link: https://lore.kernel.org/linux-arm-kernel/20200117080446.GA8980@lst.de/T/#m92bb56b04161057635d4142e1b3b9b6b0a70122e Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # for arch/riscv
2020-02-04arm64: mm: convert mm/dump.c to use walk_page_range()Steven Price
Now walk_page_range() can walk kernel page tables, we can switch the arm64 ptdump code over to using it, simplifying the code. Link: http://lkml.kernel.org/r/20191218162402.45610-22-steven.price@arm.com Signed-off-by: Steven Price <steven.price@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Liang, Kan" <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Zong Li <zong.li@sifive.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04arm64: mm: add p?d_leaf() definitionsSteven Price
walk_page_range() is going to be allowed to walk page tables other than those of user space. For this it needs to know when it has reached a 'leaf' entry in the page tables. This information will be provided by the p?d_leaf() functions/macros. For arm64, we already have p?d_sect() macros which we can reuse for p?d_leaf(). pud_sect() is defined as a dummy function when CONFIG_PGTABLE_LEVELS < 3 or CONFIG_ARM64_64K_PAGES is defined. However when the kernel is configured this way then architecturally it isn't allowed to have a large page at this level, and any code using these page walking macros is implicitly relying on the page size/number of levels being the same as the kernel. So it is safe to reuse this for p?d_leaf() as it is an architectural restriction. Link: http://lkml.kernel.org/r/20191218162402.45610-5-steven.price@arm.com Signed-off-by: Steven Price <steven.price@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Liang, Kan" <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Zong Li <zong.li@sifive.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31Merge tag 'kvm-5.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "This is the first batch of KVM changes. ARM: - cleanups and corner case fixes. PPC: - Bugfixes x86: - Support for mapping DAX areas with large nested page table entries. - Cleanups and bugfixes here too. A particularly important one is a fix for FPU load when the thread has TIF_NEED_FPU_LOAD. There is also a race condition which could be used in guest userspace to exploit the guest kernel, for which the embargo expired today. - Fast path for IPI delivery vmexits, shaving about 200 clock cycles from IPI latency. - Protect against "Spectre-v1/L1TF" (bring data in the cache via speculative out of bound accesses, use L1TF on the sibling hyperthread to read it), which unfortunately is an even bigger whack-a-mole game than SpectreV1. Sean continues his mission to rewrite KVM. In addition to a sizable number of x86 patches, this time he contributed a pretty large refactoring of vCPU creation that affects all architectures but should not have any visible effect. s390 will come next week together with some more x86 patches" * tag 'kvm-5.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) x86/KVM: Clean up host's steal time structure x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed x86/kvm: Cache gfn to pfn translation x86/kvm: Introduce kvm_(un)map_gfn() x86/kvm: Be careful not to clear KVM_VCPU_FLUSH_TLB bit KVM: PPC: Book3S PR: Fix -Werror=return-type build failure KVM: PPC: Book3S HV: Release lock on page-out failure path KVM: arm64: Treat emulated TVAL TimerValue as a signed 32-bit integer KVM: arm64: pmu: Only handle supported event counters KVM: arm64: pmu: Fix chained SW_INCR counters KVM: arm64: pmu: Don't mark a counter as chained if the odd one is disabled KVM: arm64: pmu: Don't increment SW_INCR if PMCR.E is unset KVM: x86: Use a typedef for fastop functions KVM: X86: Add 'else' to unify fastop and execute call path KVM: x86: inline memslot_valid_for_gpte KVM: x86/mmu: Use huge pages for DAX-backed files KVM: x86/mmu: Remove lpage_is_disallowed() check from set_spte() KVM: x86/mmu: Fold max_mapping_level() into kvm_mmu_hugepage_adjust() KVM: x86/mmu: Zap any compound page when collapsing sptes KVM: x86/mmu: Remove obsolete gfn restoration in FNAME(fetch) ...
2020-01-30Merge branch 'cve-2019-3016' into kvm-next-5.6Paolo Bonzini
From Boris Ostrovsky: The KVM hypervisor may provide a guest with ability to defer remote TLB flush when the remote VCPU is not running. When this feature is used, the TLB flush will happen only when the remote VPCU is scheduled to run again. This will avoid unnecessary (and expensive) IPIs. Under certain circumstances, when a guest initiates such deferred action, the hypervisor may miss the request. It is also possible that the guest may mistakenly assume that it has already marked remote VCPU as needing a flush when in fact that request had already been processed by the hypervisor. In both cases this will result in an invalid translation being present in a vCPU, potentially allowing accesses to memory locations in that guest's address space that should not be accessible. Note that only intra-guest memory is vulnerable. The five patches address both of these problems: 1. The first patch makes sure the hypervisor doesn't accidentally clear a guest's remote flush request 2. The rest of the patches prevent the race between hypervisor acknowledging a remote flush request and guest issuing a new one. Conflicts: arch/x86/kvm/x86.c [move from kvm_arch_vcpu_free to kvm_arch_vcpu_destroy]
2020-01-30Merge tag 'kvmarm-5.6' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for Linux 5.6 - Fix MMIO sign extension - Fix HYP VA tagging on tag space exhaustion - Fix PSTATE/CPSR handling when generating exception - Fix MMU notifier's advertizing of young pages - Fix poisoned page handling - Fix PMU SW event handling - Fix TVAL register access - Fix AArch32 external abort injection - Fix ITS unmapped collection handling - Various cleanups
2020-01-29Merge tag 'threads-v5.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull thread management updates from Christian Brauner: "Sargun Dhillon over the last cycle has worked on the pidfd_getfd() syscall. This syscall allows for the retrieval of file descriptors of a process based on its pidfd. A task needs to have ptrace_may_access() permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and Andy) on the target. One of the main use-cases is in combination with seccomp's user notification feature. As a reminder, seccomp's user notification feature was made available in v5.0. It allows a task to retrieve a file descriptor for its seccomp filter. The file descriptor is usually handed of to a more privileged supervising process. The supervisor can then listen for syscall events caught by the seccomp filter of the supervisee and perform actions in lieu of the supervisee, usually emulating syscalls. pidfd_getfd() is needed to expand its uses. There are currently two major users that wait on pidfd_getfd() and one future user: - Netflix, Sargun said, is working on a service mesh where users should be able to connect to a dns-based VIP. When a user connects to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be redirected to an envoy process. This service mesh uses seccomp user notifications and pidfd to intercept all connect calls and instead of connecting them to 1.2.3.4:80 connects them to e.g. 127.0.0.1:8080. - LXD uses the seccomp notifier heavily to intercept and emulate mknod() and mount() syscalls for unprivileged containers/processes. With pidfd_getfd() more uses-cases e.g. bridging socket connections will be possible. - The patchset has also seen some interest from the browser corner. Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a broker process. In the future glibc will start blocking all signals during dlopen() rendering this type of sandbox impossible. Hence, in the future Firefox will switch to a seccomp-user-nofication based sandbox which also makes use of file descriptor retrieval. The thread for this can be found at https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html With pidfd_getfd() it is e.g. possible to bridge socket connections for the supervisee (binding to a privileged port) and taking actions on file descriptors on behalf of the supervisee in general. Sargun's first version was using an ioctl on pidfds but various people pushed for it to be a proper syscall which he duely implemented as well over various review cycles. Selftests are of course included. I've also added instructions how to deal with merge conflicts below. There's also a small fix coming from the kernel mentee project to correctly annotate struct sighand_struct with __rcu to fix various sparse warnings. We've received a few more such fixes and even though they are mostly trivial I've decided to postpone them until after -rc1 since they came in rather late and I don't want to risk introducing build warnings. Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is needed to avoid allocation recursions triggerable by storage drivers that have userspace parts that run in the IO path (e.g. dm-multipath, iscsi, etc). These allocation recursions deadlock the device. The new prctl() allows such privileged userspace components to avoid allocation recursions by setting the PF_MEMALLOC_NOIO and PF_LESS_THROTTLE flags. The patch carries the necessary acks from the relevant maintainers and is routed here as part of prctl() thread-management." * tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim sched.h: Annotate sighand_struct with __rcu test: Add test for pidfd getfd arch: wire up pidfd_getfd syscall pid: Implement pidfd_getfd syscall vfs, fdtable: Add fget_task helper
2020-01-29Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull SCSI updates from James Bottomley: "This series is slightly unusual because it includes Arnd's compat ioctl tree here: 1c46a2cf2dbd Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue Excluding Arnd's changes, this is mostly an update of the usual drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas. There are a couple of core and base updates around error propagation and atomicity in the attribute container base we use for the SCSI transport classes. The rest is minor changes and updates" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits) scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity scsi: hisi_sas: Modify the file permissions of trigger_dump to write only scsi: hisi_sas: Replace magic number when handle channel interrupt scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock scsi: hisi_sas: use threaded irq to process CQ interrupts scsi: ufs: Use UFS device indicated maximum LU number scsi: ufs: Add max_lu_supported in struct ufs_dev_info scsi: ufs: Delete is_init_prefetch from struct ufs_hba scsi: ufs: Inline two functions into their callers scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init() scsi: ufs: Split ufshcd_probe_hba() based on its called flow scsi: ufs: Delete struct ufs_dev_desc scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails scsi: ufs-mediatek: enable low-power mode for hibern8 state scsi: ufs: export some functions for vendor usage scsi: ufs-mediatek: add dbg_register_dump implementation scsi: qla2xxx: Fix a NULL pointer dereference in an error path scsi: qla1280: Make checking for 64bit support consistent scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1 ...
2020-01-29Merge branch 'work.openat2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull openat2 support from Al Viro: "This is the openat2() series from Aleksa Sarai. I'm afraid that the rest of namei stuff will have to wait - it got zero review the last time I'd posted #work.namei, and there had been a leak in the posted series I'd caught only last weekend. I was going to repost it on Monday, but the window opened and the odds of getting any review during that... Oh, well. Anyway, openat2 part should be ready; that _did_ get sane amount of review and public testing, so here it comes" From Aleksa's description of the series: "For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Furthermore, the need for some sort of control over VFS's path resolution (to avoid malicious paths resulting in inadvertent breakouts) has been a very long-standing desire of many userspace applications. This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset (which was a variant of David Drysdale's O_BENEATH patchset[4] which was a spin-off of the Capsicum project[5]) with a few additions and changes made based on the previous discussion within [6] as well as others I felt were useful. In line with the conclusions of the original discussion of AT_NO_JUMPS, the flag has been split up into separate flags. However, instead of being an openat(2) flag it is provided through a new syscall openat2(2) which provides several other improvements to the openat(2) interface (see the patch description for more details). The following new LOOKUP_* flags are added: LOOKUP_NO_XDEV: Blocks all mountpoint crossings (upwards, downwards, or through absolute links). Absolute pathnames alone in openat(2) do not trigger this. Magic-link traversal which implies a vfsmount jump is also blocked (though magic-link jumps on the same vfsmount are permitted). LOOKUP_NO_MAGICLINKS: Blocks resolution through /proc/$pid/fd-style links. This is done by blocking the usage of nd_jump_link() during resolution in a filesystem. The term "magic-links" is used to match with the only reference to these links in Documentation/, but I'm happy to change the name. It should be noted that this is different to the scope of ~LOOKUP_FOLLOW in that it applies to all path components. However, you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it will *not* fail (assuming that no parent component was a magic-link), and you will have an fd for the magic-link. In order to correctly detect magic-links, the introduction of a new LOOKUP_MAGICLINK_JUMPED state flag was required. LOOKUP_BENEATH: Disallows escapes to outside the starting dirfd's tree, using techniques such as ".." or absolute links. Absolute paths in openat(2) are also disallowed. Conceptually this flag is to ensure you "stay below" a certain point in the filesystem tree -- but this requires some additional to protect against various races that would allow escape using "..". Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it can trivially beam you around the filesystem (breaking the protection). In future, there might be similar safety checks done as in LOOKUP_IN_ROOT, but that requires more discussion. In addition, two new flags are added that expand on the above ideas: LOOKUP_NO_SYMLINKS: Does what it says on the tin. No symlink resolution is allowed at all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this can still be used with NOFOLLOW to open an fd for the symlink as long as no parent path had a symlink component. LOOKUP_IN_ROOT: This is an extension of LOOKUP_BENEATH that, rather than blocking attempts to move past the root, forces all such movements to be scoped to the starting point. This provides chroot(2)-like protection but without the cost of a chroot(2) for each filesystem operation, as well as being safe against race attacks that chroot(2) is not. If a race is detected (as with LOOKUP_BENEATH) then an error is generated, and similar to LOOKUP_BENEATH it is not permitted to cross magic-links with LOOKUP_IN_ROOT. The primary need for this is from container runtimes, which currently need to do symlink scoping in userspace[7] when opening paths in a potentially malicious container. There is a long list of CVEs that could have bene mitigated by having RESOLVE_THIS_ROOT (such as CVE-2017-1002101, CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a few). In order to make all of the above more usable, I'm working on libpathrs[8] which is a C-friendly library for safe path resolution. It features a userspace-emulated backend if the kernel doesn't support openat2(2). Hopefully we can get userspace to switch to using it, and thus get openat2(2) support for free once it's ready. Future work would include implementing things like RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow programs to be sure they don't hit DoSes though stale NFS handles)" * 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Documentation: path-lookup: include new LOOKUP flags selftests: add openat2(2) selftests open: introduce openat2(2) syscall namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution namei: LOOKUP_IN_ROOT: chroot-like scoped resolution namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution namei: LOOKUP_NO_XDEV: block mountpoint crossing namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution namei: LOOKUP_NO_SYMLINKS: block symlink resolution namei: allow set_root() to produce errors namei: allow nd_jump_link() to produce errors nsfs: clean-up ns_get_path() signature to return int namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-28Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "These were the main changes in this cycle: - More -rt motivated separation of CONFIG_PREEMPT and CONFIG_PREEMPTION. - Add more low level scheduling topology sanity checks and warnings to filter out nonsensical topologies that break scheduling. - Extend uclamp constraints to influence wakeup CPU placement - Make the RT scheduler more aware of asymmetric topologies and CPU capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y - Make idle CPU selection more consistent - Various fixes, smaller cleanups, updates and enhancements - please see the git log for details" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) sched/fair: Define sched_idle_cpu() only for SMP configurations sched/topology: Assert non-NUMA topology masks don't (partially) overlap idle: fix spelling mistake "iterrupts" -> "interrupts" sched/fair: Remove redundant call to cpufreq_update_util() sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP sched/fair: calculate delta runnable load only when it's needed sched/cputime: move rq parameter in irqtime_account_process_tick stop_machine: Make stop_cpus() static sched/debug: Reset watchdog on all CPUs while processing sysrq-t sched/core: Fix size of rq::uclamp initialization sched/uclamp: Fix a bug in propagating uclamp value in new cgroups sched/fair: Load balance aggressively for SCHED_IDLE CPUs sched/fair : Improve update_sd_pick_busiest for spare capacity case watchdog: Remove soft_lockup_hrtimer_cnt and related code sched/rt: Make RT capacity-aware sched/fair: Make EAS wakeup placement consider uclamp restrictions sched/fair: Make task_fits_capacity() consider uclamp restrictions sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with() sched/uclamp: Make uclamp util helpers use and return UL values ...
2020-01-28Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "Just a handful of changes in this cycle: an ARM64 performance optimization, a comment fix and a debug output fix" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/osq: Use optimized spinning loop for arm64 locking/qspinlock: Fix inaccessible URL of MCS lock paper locking/lockdep: Fix lockdep_stats indentation problem
2020-01-28Merge branch 'efi-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Cleanup of the GOP [graphics output] handling code in the EFI stub - Complete refactoring of the mixed mode handling in the x86 EFI stub - Overhaul of the x86 EFI boot/runtime code - Increase robustness for mixed mode code - Add the ability to disable DMA at the root port level in the EFI stub - Get rid of RWX mappings in the EFI memory map and page tables, where possible - Move the support code for the old EFI memory mapping style into its only user, the SGI UV1+ support code. - plus misc fixes, updates, smaller cleanups. ... and due to interactions with the RWX changes, another round of PAT cleanups make a guest appearance via the EFI tree - with no side effects intended" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) efi/x86: Disable instrumentation in the EFI runtime handling code efi/libstub/x86: Fix EFI server boot failure efi/x86: Disallow efi=old_map in mixed mode x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping efi: Fix handling of multiple efi_fake_mem= entries efi: Fix efi_memmap_alloc() leaks efi: Add tracking for dynamically allocated memmaps efi: Add a flags parameter to efi_memory_map efi: Fix comment for efi_mem_type() wrt absent physical addresses efi/arm: Defer probe of PCIe backed efifb on DT systems efi/x86: Limit EFI old memory map to SGI UV machines efi/x86: Avoid RWX mappings for all of DRAM efi/x86: Don't map the entire kernel text RW for mixed mode x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd efi/libstub/x86: Fix unused-variable warning efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode efi/libstub/x86: Use const attribute for efi_is_64bit() efi: Allow disabling PCI busmastering on bridges during boot efi/x86: Allow translating 64-bit arguments for mixed mode calls ...
2020-01-27Merge tag 'irq-core-2020-01-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The interrupt departement provides: - A mechanism to shield isolated tasks from managed interrupts: The affinity of managed interrupts is completely controlled by the kernel and user space has no influence on them. The reason is that the automatically assigned affinity correlates to the multi-queue CPU handling of block devices. If the generated affinity mask spaws both housekeeping and isolated CPUs the interrupt could be routed to an isolated CPU which would then be disturbed by I/O submitted by a housekeeping CPU. The new mechamism ensures that as long as one housekeeping CPU is online in the assigned affinity mask the interrupt is routed to a housekeeping CPU. If there is no online housekeeping CPU in the affinity mask, then the interrupt is routed to an isolated CPU to keep the device queue intact, but unless the isolated CPU submits I/O by itself these interrupts are not raised. - A small addon to the device tree irqdomain core code to avoid duplication in irq chip drivers - Conversion of the SiFive PLIC to hierarchical domains - The usual pile of new irq chip drivers: SiFive GPIO, Aspeed SCI, NXP INTMUX, Meson A1 GPIO - The first cut of support for the new ARM GICv4.1 - The usual pile of fixes and improvements in core and driver code" * tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits) genirq, sched/isolation: Isolate from handling managed interrupts irqchip/gic-v4.1: Allow direct invalidation of VLPIs irqchip/gic-v4.1: Suppress per-VLPI doorbell irqchip/gic-v4.1: Add VPE INVALL callback irqchip/gic-v4.1: Add VPE eviction callback irqchip/gic-v4.1: Add VPE residency callback irqchip/gic-v4.1: Add mask/unmask doorbell callbacks irqchip/gic-v4.1: Plumb skeletal VPE irqchip irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP irqchip/gic-v4.1: Don't use the VPE proxy if RVPEID is set irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocation irqchip/gic-v3: Add GICv4.1 VPEID size discovery irqchip/gic-v3: Detect GICv4.1 supporting RVPEID irqchip/gic-v3-its: Fix get_vlpi_map() breakage with doorbells irqdomain: Fix a memory leak in irq_domain_push_irq() irqchip: Add NXP INTMUX interrupt multiplexer support dt-bindings: interrupt-controller: Add binding for NXP INTMUX interrupt multiplexer irqchip: Define EXYNOS_IRQ_COMBINER irqchip/meson-gpio: Add support for meson a1 SoCs ...
2020-01-27Merge tag 'timers-core-2020-01-27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The timekeeping and timers departement provides: - Time namespace support: If a container migrates from one host to another then it expects that clocks based on MONOTONIC and BOOTTIME are not subject to disruption. Due to different boot time and non-suspended runtime these clocks can differ significantly on two hosts, in the worst case time goes backwards which is a violation of the POSIX requirements. The time namespace addresses this problem. It allows to set offsets for clock MONOTONIC and BOOTTIME once after creation and before tasks are associated with the namespace. These offsets are taken into account by timers and timekeeping including the VDSO. Offsets for wall clock based clocks (REALTIME/TAI) are not provided by this mechanism. While in theory possible, the overhead and code complexity would be immense and not justified by the esoteric potential use cases which were discussed at Plumbers '18. The overhead for tasks in the root namespace (ie where host time offsets = 0) is in the noise and great effort was made to ensure that especially in the VDSO. If time namespace is disabled in the kernel configuration the code is compiled out. Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature and kept on for more than a year addressing review comments, finding better solutions. A pleasant experience. - Overhaul of the alarmtimer device dependency handling to ensure that the init/suspend/resume ordering is correct. - A new clocksource/event driver for Microchip PIT64 - Suspend/resume support for the Hyper-V clocksource - The usual pile of fixes, updates and improvements mostly in the driver code" * tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n alarmtimer: Use wakeup source from alarmtimer platform device alarmtimer: Make alarmtimer platform device child of RTC device alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality hrtimer: Add missing sparse annotation for __run_timer() lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres() MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources clocksource/drivers/timer-microchip-pit64b: Fix sparse warning clocksource/drivers/exynos_mct: Rename Exynos to lowercase clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access clocksource/drivers/timer-ti-dm: Switch to platform_get_irq clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource clocksource/drivers/bcm2835_timer: Fix memory leak of timer clocksource/drivers/cadence-ttc: Use ttc driver as platform driver clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page ...
2020-01-27KVM: Move running VCPU from ARM to common codePaolo Bonzini
For ring-based dirty log tracking, it will be more efficient to account writes during schedule-out or schedule-in to the currently running VCPU. We would like to do it even if the write doesn't use the current VCPU's address space, as is the case for cached writes (see commit 4e335d9e7ddb, "Revert "KVM: Support vCPU-based gfn->hva cache"", 2017-05-02). Therefore, add a mechanism to track the currently-loaded kvm_vcpu struct. There is already something similar in KVM/ARM; one important difference is that kvm_arch_vcpu_{load,put} have two callers in virt/kvm/kvm_main.c: we have to update both the architecture-independent vcpu_{load,put} and the preempt notifiers. Another change made in the process is to allow using kvm_get_running_vcpu() in preemptible code. This is allowed because preempt notifiers ensure that the value does not change even after the VCPU thread is migrated. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27KVM: Drop kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit()Sean Christopherson
Remove kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit() now that all arch specific implementations are nops. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27KVM: arm64: Free sve_state via arm specific hookSean Christopherson
Add an arm specific hook to free the arm64-only sve_state. Doing so eliminates the last functional code from kvm_arch_vcpu_uninit() across all architectures and paves the way for removing kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit() entirely. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The changes are a real mixed bag this time around. The only scary looking one from the diffstat is the uapi change to asm-generic/mman-common.h, but this has been acked by Arnd and is actually just adding a pair of comments in an attempt to prevent allocation of some PROT values which tend to get used for arch-specific purposes. We'll be using them for Branch Target Identification (a CFI-like hardening feature), which is currently under review on the mailing list. New architecture features: - Support for Armv8.5 E0PD, which benefits KASLR in the same way as KPTI but without the overhead. This allows KPTI to be disabled on CPUs that are not affected by Meltdown, even is KASLR is enabled. - Initial support for the Armv8.5 RNG instructions, which claim to provide access to a high bandwidth, cryptographically secure hardware random number generator. As well as exposing these to userspace, we also use them as part of the KASLR seed and to seed the crng once all CPUs have come online. - Advertise a bunch of new instructions to userspace, including support for Data Gathering Hint, Matrix Multiply and 16-bit floating point. Kexec: - Cleanups in preparation for relocating with the MMU enabled - Support for loading crash dump kernels with kexec_file_load() Perf and PMU drivers: - Cleanups and non-critical fixes for a couple of system PMU drivers FPU-less (aka broken) CPU support: - Considerable fixes to support CPUs without the FP/SIMD extensions, including their presence in heterogeneous systems. Good luck finding a 64-bit userspace that handles this. Modern assembly function annotations: - Start migrating our use of ENTRY() and ENDPROC() over to the new-fangled SYM_{CODE,FUNC}_{START,END} macros, which are intended to aid debuggers Kbuild: - Cleanup detection of LSE support in the assembler by introducing 'as-instr' - Remove compressed Image files when building clean targets IP checksumming: - Implement optimised IPv4 checksumming routine when hardware offload is not in use. An IPv6 version is in the works, pending testing. Hardware errata: - Work around Cortex-A55 erratum #1530923 Shadow call stack: - Work around some issues with Clang's integrated assembler not liking our perfectly reasonable assembly code - Avoid allocating the X18 register, so that it can be used to hold the shadow call stack pointer in future ACPI: - Fix ID count checking in IORT code. This may regress broken firmware that happened to work with the old implementation, in which case we'll have to revert it and try something else - Fix DAIF corruption on return from GHES handler with pseudo-NMIs Miscellaneous: - Whitelist some CPUs that are unaffected by Spectre-v2 - Reduce frequency of ASID rollover when KPTI is compiled in but inactive - Reserve a couple of arch-specific PROT flags that are already used by Sparc and PowerPC and are planned for later use with BTI on arm64 - Preparatory cleanup of our entry assembly code in preparation for moving more of it into C later on - Refactoring and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (73 commits) arm64: acpi: fix DAIF manipulation with pNMI arm64: kconfig: Fix alignment of E0PD help text arm64: Use v8.5-RNG entropy for KASLR seed arm64: Implement archrandom.h for ARMv8.5-RNG arm64: kbuild: remove compressed images on 'make ARCH=arm64 (dist)clean' arm64: entry: Avoid empty alternatives entries arm64: Kconfig: select HAVE_FUTEX_CMPXCHG arm64: csum: Fix pathological zero-length calls arm64: entry: cleanup sp_el0 manipulation arm64: entry: cleanup el0 svc handler naming arm64: entry: mark all entry code as notrace arm64: assembler: remove smp_dmb macro arm64: assembler: remove inherit_daif macro ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map() mm: Reserve asm-generic prot flags 0x10 and 0x20 for arch use arm64: Use macros instead of hard-coded constants for MAIR_EL1 arm64: Add KRYO{3,4}XX CPU cores to spectre-v2 safe list arm64: kernel: avoid x18 in __cpu_soft_restart arm64: kvm: stop treating register x18 as caller save arm64/lib: copy_page: avoid x18 register in assembler code ...
2020-01-23arm64: KVM: Add UAPI notes for swapped registersAndrew Jones
Two UAPI system register IDs do not derive their values from the ARM system register encodings. This is because their values were accidentally swapped. As the IDs are API, they cannot be changed. Add WARNING notes to point them out. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Andrew Jones <drjones@redhat.com> [maz: turned XXX into WARNING] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200120130825.28838-1-drjones@redhat.com
2020-01-23KVM: arm/arm64: Cleanup MMIO handlingMarc Zyngier
Our MMIO handling is a bit odd, in the sense that it uses an intermediate per-vcpu structure to store the various decoded information that describe the access. But the same information is readily available in the HSR/ESR_EL2 field, and we actually use this field to populate the structure. Let's simplify the whole thing by getting rid of the superfluous structure and save a (tiny) bit of space in the vcpu structure. [32bit fix courtesy of Olof Johansson <olof@lixom.net>] Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-01-22arm64: acpi: fix DAIF manipulation with pNMIMark Rutland
Since commit: d44f1b8dd7e66d80 ("arm64: KVM/mm: Move SEA handling behind a single 'claim' interface") ... the top-level APEI SEA handler has the shape: 1. current_flags = arch_local_save_flags() 2. local_daif_restore(DAIF_ERRCTX) 3. <GHES handler> 4. local_daif_restore(current_flags) However, since commit: 4a503217ce37e1f4 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking") ... when pseudo-NMIs (pNMIs) are in use, arch_local_save_flags() will save the PMR value rather than the DAIF flags. The combination of these two commits means that the APEI SEA handler will erroneously attempt to restore the PMR value into DAIF. Fix this by factoring local_daif_save_flags() out of local_daif_save(), so that we can consistently save DAIF in step #1, regardless of whether pNMIs are in use. Both commits were introduced concurrently in v5.0. Cc: <stable@vger.kernel.org> Fixes: 4a503217ce37e1f4 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking") Fixes: d44f1b8dd7e66d80 ("arm64: KVM/mm: Move SEA handling behind a single 'claim' interface") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-01-22irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocationMarc Zyngier
GICv4.1 defines a new VPE table that is potentially shared between both the ITSs and the redistributors, following complicated affinity rules. To make things more confusing, the programming of this table at the redistributor level is reusing the GICv4.0 GICR_VPROPBASER register for something completely different. The code flow is somewhat complexified by the need to respect the affinities required by the HW, meaning that tables can either be inherited from a previously discovered ITS or redistributor. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Link: https://lore.kernel.org/r/20191224111055.11836-6-maz@kernel.org
2020-01-22Merge branch 'for-next/rng' into for-next/coreWill Deacon
* for-next/rng: (2 commits) arm64: Use v8.5-RNG entropy for KASLR seed ...
2020-01-22Merge branch 'for-next/errata' into for-next/coreWill Deacon
* for-next/errata: (3 commits) arm64: Workaround for Cortex-A55 erratum 1530923 ...
2020-01-22Merge branch 'for-next/asm-annotations' into for-next/coreWill Deacon
* for-next/asm-annotations: (6 commits) arm64: kernel: Correct annotation of end of el0_sync ...
2020-01-22Merge branches 'for-next/acpi', 'for-next/cpufeatures', 'for-next/csum', ↵Will Deacon
'for-next/e0pd', 'for-next/entry', 'for-next/kbuild', 'for-next/kexec/cleanup', 'for-next/kexec/file-kdump', 'for-next/misc', 'for-next/nofpsimd', 'for-next/perf' and 'for-next/scs' into for-next/core * for-next/acpi: ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map() * for-next/cpufeatures: (2 commits) arm64: Introduce ID_ISAR6 CPU register ... * for-next/csum: (2 commits) arm64: csum: Fix pathological zero-length calls ... * for-next/e0pd: (7 commits) arm64: kconfig: Fix alignment of E0PD help text ... * for-next/entry: (5 commits) arm64: entry: cleanup sp_el0 manipulation ... * for-next/kbuild: (4 commits) arm64: kbuild: remove compressed images on 'make ARCH=arm64 (dist)clean' ... * for-next/kexec/cleanup: (11 commits) Revert "arm64: kexec: make dtb_mem always enabled" ... * for-next/kexec/file-kdump: (2 commits) arm64: kexec_file: add crash dump support ... * for-next/misc: (12 commits) arm64: entry: Avoid empty alternatives entries ... * for-next/nofpsimd: (7 commits) arm64: nofpsmid: Handle TIF_FOREIGN_FPSTATE flag cleanly ... * for-next/perf: (2 commits) perf/imx_ddr: Fix cpu hotplug state cleanup ... * for-next/scs: (6 commits) arm64: kernel: avoid x18 in __cpu_soft_restart ...
2020-01-22arm64: Use v8.5-RNG entropy for KASLR seedMark Brown
When seeding KALSR on a system where we have architecture level random number generation make use of that entropy, mixing it in with the seed passed by the bootloader. Since this is run very early in init before feature detection is complete we open code rather than use archrandom.h. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-01-22arm64: Implement archrandom.h for ARMv8.5-RNGRichard Henderson
Expose the ID_AA64ISAR0.RNDR field to userspace, as the RNG system registers are always available at EL0. Implement arch_get_random_seed_long using RNDR. Given that the TRNG is likely to be a shared resource between cores, and VMs, do not explicitly force re-seeding with RNDRRS. In order to avoid code complexity and potential issues with hetrogenous systems only provide values after cpufeature has finalized the system capabilities. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> [Modified to only function after cpufeature has finalized the system capabilities and move all the code into the header -- broonie] Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> [will: Advertise HWCAP via /proc/cpuinfo] Signed-off-by: Will Deacon <will@kernel.org>
2020-01-20Merge tag 'v5.5-rc7' into efi/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-19KVM: arm/arm64: Correct AArch32 SPSR on exception entryMark Rutland
Confusingly, there are three SPSR layouts that a kernel may need to deal with: (1) An AArch64 SPSR_ELx view of an AArch64 pstate (2) An AArch64 SPSR_ELx view of an AArch32 pstate (3) An AArch32 SPSR_* view of an AArch32 pstate When the KVM AArch32 support code deals with SPSR_{EL2,HYP}, it's either dealing with #2 or #3 consistently. On arm64 the PSR_AA32_* definitions match the AArch64 SPSR_ELx view, and on arm the PSR_AA32_* definitions match the AArch32 SPSR_* view. However, when we inject an exception into an AArch32 guest, we have to synthesize the AArch32 SPSR_* that the guest will see. Thus, an AArch64 host needs to synthesize layout #3 from layout #2. This patch adds a new host_spsr_to_spsr32() helper for this, and makes use of it in the KVM AArch32 support code. For arm64 we need to shuffle the DIT bit around, and remove the SS bit, while for arm we can use the value as-is. I've open-coded the bit manipulation for now to avoid having to rework the existing PSR_* definitions into PSR64_AA32_* and PSR32_AA32_* definitions. I hope to perform a more thorough refactoring in future so that we can handle pstate view manipulation more consistently across the kernel tree. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-4-mark.rutland@arm.com
2020-01-19KVM: arm/arm64: Correct CPSR on exception entryMark Rutland
When KVM injects an exception into a guest, it generates the CPSR value from scratch, configuring CPSR.{M,A,I,T,E}, and setting all other bits to zero. This isn't correct, as the architecture specifies that some CPSR bits are (conditionally) cleared or set upon an exception, and others are unchanged from the original context. This patch adds logic to match the architectural behaviour. To make this simple to follow/audit/extend, documentation references are provided, and bits are configured in order of their layout in SPSR_EL2. This layout can be seen in the diagram on ARM DDI 0487E.a page C5-426. Note that this code is used by both arm and arm64, and is intended to fuction with the SPSR_EL2 and SPSR_HYP layouts. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-3-mark.rutland@arm.com
2020-01-19KVM: arm64: Correct PSTATE on exception entryMark Rutland
When KVM injects an exception into a guest, it generates the PSTATE value from scratch, configuring PSTATE.{M[4:0],DAIF}, and setting all other bits to zero. This isn't correct, as the architecture specifies that some PSTATE bits are (conditionally) cleared or set upon an exception, and others are unchanged from the original context. This patch adds logic to match the architectural behaviour. To make this simple to follow/audit/extend, documentation references are provided, and bits are configured in order of their layout in SPSR_EL2. This layout can be seen in the diagram on ARM DDI 0487E.a page C5-429. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-2-mark.rutland@arm.com
2020-01-19KVM: arm64: Only sign-extend MMIO up to register widthChristoffer Dall
On AArch64 you can do a sign-extended load to either a 32-bit or 64-bit register, and we should only sign extend the register up to the width of the register as specified in the operation (by using the 32-bit Wn or 64-bit Xn register specifier). As it turns out, the architecture provides this decoding information in the SF ("Sixty-Four" -- how cute...) bit. Let's take advantage of this with the usual 32-bit/64-bit header file dance and do the right thing on AArch64 hosts. Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20191212195055.5541-1-christoffer.dall@arm.com
2020-01-18open: introduce openat2(2) syscallAleksa Sarai
/* Background. */ For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Userspace also has a hard time figuring out whether a particular flag is supported on a particular kernel. While it is now possible with contemporary kernels (thanks to [3]), older kernels will expose unknown flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during openat(2) time matches modern syscall designs and is far more fool-proof. In addition, the newly-added path resolution restriction LOOKUP flags (which we would like to expose to user-space) don't feel related to the pre-existing O_* flag set -- they affect all components of path lookup. We'd therefore like to add a new flag argument. Adding a new syscall allows us to finally fix the flag-ignoring problem, and we can make it extensible enough so that we will hopefully never need an openat3(2). /* Syscall Prototype. */ /* * open_how is an extensible structure (similar in interface to * clone3(2) or sched_setattr(2)). The size parameter must be set to * sizeof(struct open_how), to allow for future extensions. All future * extensions will be appended to open_how, with their zero value * acting as a no-op default. */ struct open_how { /* ... */ }; int openat2(int dfd, const char *pathname, struct open_how *how, size_t size); /* Description. */ The initial version of 'struct open_how' contains the following fields: flags Used to specify openat(2)-style flags. However, any unknown flag bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR) will result in -EINVAL. In addition, this field is 64-bits wide to allow for more O_ flags than currently permitted with openat(2). mode The file mode for O_CREAT or O_TMPFILE. Must be set to zero if flags does not contain O_CREAT or O_TMPFILE. resolve Restrict path resolution (in contrast to O_* flags they affect all path components). The current set of flags are as follows (at the moment, all of the RESOLVE_ flags are implemented as just passing the corresponding LOOKUP_ flag). RESOLVE_NO_XDEV => LOOKUP_NO_XDEV RESOLVE_NO_SYMLINKS => LOOKUP_NO_SYMLINKS RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS RESOLVE_BENEATH => LOOKUP_BENEATH RESOLVE_IN_ROOT => LOOKUP_IN_ROOT open_how does not contain an embedded size field, because it is of little benefit (userspace can figure out the kernel open_how size at runtime fairly easily without it). It also only contains u64s (even though ->mode arguably should be a u16) to avoid having padding fields which are never used in the future. Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE is no longer permitted for openat(2). As far as I can tell, this has always been a bug and appears to not be used by userspace (and I've not seen any problems on my machines by disallowing it). If it turns out this breaks something, we can special-case it and only permit it for openat(2) but not openat2(2). After input from Florian Weimer, the new open_how and flag definitions are inside a separate header from uapi/linux/fcntl.h, to avoid problems that glibc has with importing that header. /* Testing. */ In a follow-up patch there are over 200 selftests which ensure that this syscall has the correct semantics and will correctly handle several attack scenarios. In addition, I've written a userspace library[4] which provides convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care must be taken when using RESOLVE_IN_ROOT'd file descriptors with other syscalls). During the development of this patch, I've run numerous verification tests using libpathrs (showing that the API is reasonably usable by userspace). /* Future Work. */ Additional RESOLVE_ flags have been suggested during the review period. These can be easily implemented separately (such as blocking auto-mount during resolution). Furthermore, there are some other proposed changes to the openat(2) interface (the most obvious example is magic-link hardening[5]) which would be a good opportunity to add a way for userspace to restrict how O_PATH file descriptors can be re-opened. Another possible avenue of future work would be some kind of CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace which openat2(2) flags and fields are supported by the current kernel (to avoid userspace having to go through several guesses to figure it out). [1]: https://lwn.net/Articles/588444/ [2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com [3]: commit 629e014bb834 ("fs: completely ignore unknown open flags") [4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523 [5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/ [6]: https://youtu.be/ggD-eb3yPVs Suggested-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>