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2018-06-04Merge branch 'siginfo-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo updates from Eric Biederman: "This set of changes close the known issues with setting si_code to an invalid value, and with not fully initializing struct siginfo. There remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64 and x86 to get the code that generates siginfo into a simpler and more maintainable state. Most of that work involves refactoring the signal handling code and thus careful code review. Also not included is the work to shrink the in kernel version of struct siginfo. That depends on getting the number of places that directly manipulate struct siginfo under control, as it requires the introduction of struct kernel_siginfo for the in kernel things. Overall this set of changes looks like it is making good progress, and with a little luck I will be wrapping up the siginfo work next development cycle" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) signal/sh: Stop gcc warning about an impossible case in do_divide_error signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions signal/um: More carefully relay signals in relay_signal. signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR} signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code signal/signalfd: Add support for SIGSYS signal/signalfd: Remove __put_user from signalfd_copyinfo signal/xtensa: Use force_sig_fault where appropriate signal/xtensa: Consistenly use SIGBUS in do_unaligned_user signal/um: Use force_sig_fault where appropriate signal/sparc: Use force_sig_fault where appropriate signal/sparc: Use send_sig_fault where appropriate signal/sh: Use force_sig_fault where appropriate signal/s390: Use force_sig_fault where appropriate signal/riscv: Replace do_trap_siginfo with force_sig_fault signal/riscv: Use force_sig_fault where appropriate signal/parisc: Use force_sig_fault where appropriate signal/parisc: Use force_sig_mceerr where appropriate signal/openrisc: Use force_sig_fault where appropriate signal/nios2: Use force_sig_fault where appropriate ...
2018-06-04Merge branch 'work.aio-1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull aio updates from Al Viro: "Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly. The only thing I'm holding back for a day or so is Adam's aio ioprio - his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case), but let it sit in -next for decency sake..." * 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) aio: sanitize the limit checking in io_submit(2) aio: fold do_io_submit() into callers aio: shift copyin of iocb into io_submit_one() aio_read_events_ring(): make a bit more readable aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way aio: take list removal to (some) callers of aio_complete() aio: add missing break for the IOCB_CMD_FDSYNC case random: convert to ->poll_mask timerfd: convert to ->poll_mask eventfd: switch to ->poll_mask pipe: convert to ->poll_mask crypto: af_alg: convert to ->poll_mask net/rxrpc: convert to ->poll_mask net/iucv: convert to ->poll_mask net/phonet: convert to ->poll_mask net/nfc: convert to ->poll_mask net/caif: convert to ->poll_mask net/bluetooth: convert to ->poll_mask net/sctp: convert to ->poll_mask net/tipc: convert to ->poll_mask ...
2018-05-26fs: add new vfs_poll and file_can_poll helpersChristoph Hellwig1-1/+1
These abstract out calls to the poll method in preparation for changes in how we poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-15KVM: arm/arm64: VGIC/ITS save/restore: protect kvm_read_guest() callsAndre Przywara2-4/+4
kvm_read_guest() will eventually look up in kvm_memslots(), which requires either to hold the kvm->slots_lock or to be inside a kvm->srcu critical section. In contrast to x86 and s390 we don't take the SRCU lock on every guest exit, so we have to do it individually for each kvm_read_guest() call. Use the newly introduced wrapper for that. Cc: Stable <stable@vger.kernel.org> # 4.12+ Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-15KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lockAndre Przywara1-7/+8
kvm_read_guest() will eventually look up in kvm_memslots(), which requires either to hold the kvm->slots_lock or to be inside a kvm->srcu critical section. In contrast to x86 and s390 we don't take the SRCU lock on every guest exit, so we have to do it individually for each kvm_read_guest() call. Provide a wrapper which does that and use that everywhere. Note that ending the SRCU critical section before returning from the kvm_read_guest() wrapper is safe, because the data has been *copied*, so we don't need to rely on valid references to the memslot anymore. Cc: Stable <stable@vger.kernel.org> # 4.8+ Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-15KVM: arm/arm64: VGIC/ITS: Promote irq_lock() in update_affinityAndre Przywara1-2/+3
Apparently the development of update_affinity() overlapped with the promotion of irq_lock to be _irqsave, so the patch didn't convert this lock over. This will make lockdep complain. Fix this by disabling IRQs around the lock. Cc: stable@vger.kernel.org Fixes: 08c9fd042117 ("KVM: arm/arm64: vITS: Add a helper to update the affinity of an LPI") Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-15KVM: arm/arm64: Properly protect VGIC locks from IRQsAndre Przywara3-14/+23
As Jan reported [1], lockdep complains about the VGIC not being bullet proof. This seems to be due to two issues: - When commit 006df0f34930 ("KVM: arm/arm64: Support calling vgic_update_irq_pending from irq context") promoted irq_lock and ap_list_lock to _irqsave, we forgot two instances of irq_lock. lockdeps seems to pick those up. - If a lock is _irqsave, any other locks we take inside them should be _irqsafe as well. So the lpi_list_lock needs to be promoted also. This fixes both issues by simply making the remaining instances of those locks _irqsave. One irq_lock is addressed in a separate patch, to simplify backporting. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-May/575718.html Cc: stable@vger.kernel.org Fixes: 006df0f34930 ("KVM: arm/arm64: Support calling vgic_update_irq_pending from irq context") Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-05Merge tag 'kvmarm-fixes-for-4.17-2' of ↵Radim Krčmář6-62/+81
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm KVM/arm fixes for 4.17, take #2 - Fix proxying of GICv2 CPU interface accesses - Fix crash when switching to BE - Track source vcpu git GICv2 SGIs - Fix an outdated bit of documentation
2018-05-04KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenanceValentin Schneider1-1/+1
One comment still mentioned process_maintenance operations after commit af0614991ab6 ("KVM: arm/arm64: vgic: Get rid of unnecessary process_maintenance operation") Update the comment to point to vgic_fold_lr_state instead, which is where maintenance interrupts are taken care of. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-27rMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds3-5/+78
Pull KVM fixes from Radim Krčmář: "ARM: - PSCI selection API, a leftover from 4.16 (for stable) - Kick vcpu on active interrupt affinity change - Plug a VMID allocation race on oversubscribed systems - Silence debug messages - Update Christoffer's email address (linaro -> arm) x86: - Expose userspace-relevant bits of a newly added feature - Fix TLB flushing on VMX with VPID, but without EPT" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: x86/headers/UAPI: Move DISABLE_EXITS KVM capability bits to the UAPI kvm: apic: Flush TLB after APIC mode/address change if VPIDs are in use arm/arm64: KVM: Add PSCI version selection API KVM: arm/arm64: vgic: Kick new VCPU on interrupt migration arm64: KVM: Demote SVE and LORegion warnings to debug only MAINTAINERS: Update e-mail address for Christoffer Dall KVM: arm/arm64: Close VMID generation race
2018-04-27KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGIMarc Zyngier5-61/+80
Now that we make sure we don't inject multiple instances of the same GICv2 SGI at the same time, we've made another bug more obvious: If we exit with an active SGI, we completely lose track of which vcpu it came from. On the next entry, we restore it with 0 as a source, and if that wasn't the right one, too bad. While this doesn't seem to trouble GIC-400, the architectural model gets offended and doesn't deactivate the interrupt on EOI. Another connected issue is that we will happilly make pending an interrupt from another vcpu, overriding the above zero with something that is just as inconsistent. Don't do that. The final issue is that we signal a maintenance interrupt when no pending interrupts are present in the LR. Assuming we've fixed the two issues above, we end-up in a situation where we keep exiting as soon as we've reached the active state, and not be able to inject the following pending. The fix comes in 3 parts: - GICv2 SGIs have their source vcpu saved if they are active on exit, and restored on entry - Multi-SGIs cannot go via the Pending+Active state, as this would corrupt the source field - Multi-SGIs are converted to using MI on EOI instead of NPIE Fixes: 16ca6a607d84bef0 ("KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintid") Reported-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-26KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_mmio_read_apr()Mark Rutland1-0/+5
It's possible for userspace to control n. Sanitize n when using it as an array index. Note that while it appears that n must be bound to the interval [0,3] due to the way it is extracted from addr, we cannot guarantee that compiler transformations (and/or future refactoring) will ensure this is the case, and given this is a slow path it's better to always perform the masking. Found by smatch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-26KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_get_irq()Mark Rutland1-4/+10
It's possible for userspace to control intid. Sanitize intid when using it as an array index. At the same time, sort the includes when adding <linux/nospec.h>. Found by smatch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman1-0/+1
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-20arm/arm64: KVM: Add PSCI version selection APIMarc Zyngier1-0/+60
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1 or 1.0 to a guest, defaulting to the latest version of the PSCI implementation that is compatible with the requested version. This is no different from doing a firmware upgrade on KVM. But in order to give a chance to hypothetical badly implemented guests that would have a fit by discovering something other than PSCI 0.2, let's provide a new API that allows userspace to pick one particular version of the API. This is implemented as a new class of "firmware" registers, where we expose the PSCI version. This allows the PSCI version to be save/restored as part of a guest migration, and also set to any supported version if the guest requires it. Cc: stable@vger.kernel.org #4.16 Reviewed-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-17KVM: arm/arm64: vgic: Kick new VCPU on interrupt migrationAndre Przywara1-0/+8
When vgic_prune_ap_list() finds an interrupt that needs to be migrated to a new VCPU, we should notify this VCPU of the pending interrupt, since it requires immediate action. Kick this VCPU once we have added the new IRQ to the list, but only after dropping the locks. Reported-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-17KVM: arm/arm64: Close VMID generation raceMarc Zyngier1-5/+10
Before entering the guest, we check whether our VMID is still part of the current generation. In order to avoid taking a lock, we start with checking that the generation is still current, and only if not current do we take the lock, recheck, and update the generation and VMID. This leaves open a small race: A vcpu can bump up the global generation number as well as the VM's, but has not updated the VMID itself yet. At that point another vcpu from the same VM comes in, checks the generation (and finds it not needing anything), and jumps into the guest. At this point, we end-up with two vcpus belonging to the same VM running with two different VMIDs. Eventually, the VMID used by the second vcpu will get reassigned, and things will really go wrong... A simple solution would be to drop this initial check, and always take the lock. This is likely to cause performance issues. A middle ground is to convert the spinlock to a rwlock, and only take the read lock on the fast path. If the check fails at that point, drop it and acquire the write lock, rechecking the condition. This ensures that the above scenario doesn't occur. Cc: stable@vger.kernel.org Reported-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Shannon Zhao <zhaoshenglong@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-28Merge tag 'kvm-arm-for-v4.17' of ↵Radim Krčmář15-489/+650
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm KVM/ARM updates for v4.17 - VHE optimizations - EL2 address space randomization - Variant 3a mitigation for Cortex-A57 and A72 - The usual vgic fixes - Various minor tidying-up
2018-03-26KVM: arm/arm64: vgic-its: Fix potential overrun in vgic_copy_lpi_listMarc Zyngier1-6/+9
vgic_copy_lpi_list() parses the LPI list and picks LPIs targeting a given vcpu. We allocate the array containing the intids before taking the lpi_list_lock, which means we can have an array size that is not equal to the number of LPIs. This is particularly obvious when looking at the path coming from vgic_enable_lpis, which is not a command, and thus can run in parallel with commands: vcpu 0: vcpu 1: vgic_enable_lpis its_sync_lpi_pending_table vgic_copy_lpi_list intids = kmalloc_array(irq_count) MAPI(lpi targeting vcpu 0) list_for_each_entry(lpi_list_head) intids[i++] = irq->intid; At that stage, we will happily overrun the intids array. Boo. An easy fix is is to break once the array is full. The MAPI command will update the config anyway, and we won't miss a thing. We also make sure that lpi_list_count is read exactly once, so that further updates of that value will not affect the array bound check. Cc: stable@vger.kernel.org Fixes: ccb1d791ab9e ("KVM: arm64: vgic-its: Fix pending table sync") Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-26KVM: arm/arm64: vgic: Disallow Active+Pending for level interruptsMarc Zyngier2-48/+60
It was recently reported that VFIO mediated devices, and anything that VFIO exposes as level interrupts, do no strictly follow the expected logic of such interrupts as it only lowers the input line when the guest has EOId the interrupt at the GIC level, rather than when it Acked the interrupt at the device level. THe GIC's Active+Pending state is fundamentally incompatible with this behaviour, as it prevents KVM from observing the EOI, and in turn results in VFIO never dropping the line. This results in an interrupt storm in the guest, which it really never expected. As we cannot really change VFIO to follow the strict rules of level signalling, let's forbid the A+P state altogether, as it is in the end only an optimization. It ensures that we will transition via an invalid state, which we can use to notify VFIO of the EOI. Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Eric Auger <eric.auger@redhat.com> Tested-by: Shunyong Yang <shunyong.yang@hxt-semitech.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19Merge tag 'kvm-arm-fixes-for-v4.16-2' into HEADMarc Zyngier7-72/+169
Resolve conflicts with current mainline
2018-03-19arm/arm64: KVM: Introduce EL2-specific executable mappingsMarc Zyngier1-21/+59
Until now, all EL2 executable mappings were derived from their EL1 VA. Since we want to decouple the vectors mapping from the rest of the hypervisor, we need to be able to map some text somewhere else. The "idmap" region (for lack of a better name) is ideally suited for this, as we have a huge range that hardly has anything in it. Let's extend the IO allocator to also deal with executable mappings, thus providing the required feature. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19arm64: KVM: Introduce EL2 VA randomisationMarc Zyngier1-1/+1
The main idea behind randomising the EL2 VA is that we usually have a few spare bits between the most significant bit of the VA mask and the most significant bit of the linear mapping. Those bits could be a bunch of zeroes, and could be useful to move things around a bit. Of course, the more memory you have, the less randomisation you get... Alternatively, these bits could be the result of KASLR, in which case they are already random. But it would be nice to have a *different* randomization, just to make the job of a potential attacker a bit more difficult. Inserting these random bits is a bit involved. We don't have a spare register (short of rewriting all the kern_hyp_va call sites), and the immediate we want to insert is too random to be used with the ORR instruction. The best option I could come up with is the following sequence: and x0, x0, #va_mask ror x0, x0, #first_random_bit add x0, x0, #(random & 0xfff) add x0, x0, #(random >> 12), lsl #12 ror x0, x0, #(63 - first_random_bit) making it a fairly long sequence, but one that a decent CPU should be able to execute without breaking a sweat. It is of course NOPed out on VHE. The last 4 instructions can also be turned into NOPs if it appears that there is no free bits to use. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move HYP IO VAs to the "idmap" rangeMarc Zyngier1-14/+59
We so far mapped our HYP IO (which is essentially the GICv2 control registers) using the same method as for memory. It recently appeared that is a bit unsafe: We compute the HYP VA using the kern_hyp_va helper, but that helper is only designed to deal with kernel VAs coming from the linear map, and not from the vmalloc region... This could in turn cause some bad aliasing between the two, amplified by the upcoming VA randomisation. A solution is to come up with our very own basic VA allocator for MMIO. Since half of the HYP address space only contains a single page (the idmap), we have plenty to borrow from. Let's use the idmap as a base, and allocate downwards from it. GICv2 now lives on the other side of the great VA barrier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm64: Fix HYP idmap unmap when using 52bit PAMarc Zyngier1-5/+21
Unmapping the idmap range using 52bit PA is quite broken, as we don't take into account the right number of PGD entries, and rely on PTRS_PER_PGD. The result is that pgd_index() truncates the address, and we end-up in the weed. Let's introduce a new unmap_hyp_idmap_range() that knows about this, together with a kvm_pgd_index() helper, which hides a bit of the complexity of the issue. Fixes: 98732d1b189b ("KVM: arm/arm64: fix HYP ID map extension to 52 bits") Reported-by: James Morse <james.morse@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Fix idmap size and alignmentMarc Zyngier1-0/+2
Although the idmap section of KVM can only be at most 4kB and must be aligned on a 4kB boundary, the rest of the code expects it to be page aligned. Things get messy when tearing down the HYP page tables when PAGE_SIZE is 64K, and the idmap section isn't 64K aligned. Let's fix this by computing aligned boundaries that the HYP code will use. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: James Morse <james.morse@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Keep GICv2 HYP VAs in kvm_vgic_global_stateMarc Zyngier3-25/+27
As we're about to change the way we map devices at HYP, we need to move away from kern_hyp_va on an IO address. One way of achieving this is to store the VAs in kvm_vgic_global_state, and use that directly from the HYP code. This requires a small change to create_hyp_io_mappings so that it can also return a HYP VA. We take this opportunity to nuke the vctrl_base field in the emulated distributor, as it is not used anymore. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move ioremap calls to create_hyp_io_mappingsMarc Zyngier2-33/+22
Both HYP io mappings call ioremap, followed by create_hyp_io_mappings. Let's move the ioremap call into create_hyp_io_mappings itself, which simplifies the code a bit and allows for further refactoring. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Demote HYP VA range display to being a debug featureMarc Zyngier1-3/+4
Displaying the HYP VA information is slightly counterproductive when using VA randomization. Turn it into a debug feature only, and adjust the last displayed value to reflect the top of RAM instead of ~0. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Avoid VGICv3 save/restore on VHE with no IRQsChristoffer Dall3-48/+87
We can finally get completely rid of any calls to the VGICv3 save/restore functions when the AP lists are empty on VHE systems. This requires carefully factoring out trap configuration from saving and restoring state, and carefully choosing what to do on the VHE and non-VHE path. One of the challenges is that we cannot save/restore the VMCR lazily because we can only write the VMCR when ICC_SRE_EL1.SRE is cleared when emulating a GICv2-on-GICv3, since otherwise all Group-0 interrupts end up being delivered as FIQ. To solve this problem, and still provide fast performance in the fast path of exiting a VM when no interrupts are pending (which also optimized the latency for actually delivering virtual interrupts coming from physical interrupts), we orchestrate a dance of only doing the activate/deactivate traps in vgic load/put for VHE systems (which can have ICC_SRE_EL1.SRE cleared when running in the host), and doing the configuration on every round-trip on non-VHE systems. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move VGIC APR save/restore to vgic put/loadChristoffer Dall3-62/+74
The APRs can only have bits set when the guest acknowledges an interrupt in the LR and can only have a bit cleared when the guest EOIs an interrupt in the LR. Therefore, if we have no LRs with any pending/active interrupts, the APR cannot change value and there is no need to clear it on every exit from the VM (hint: it will have already been cleared when we exited the guest the last time with the LRs all EOIed). The only case we need to take care of is when we migrate the VCPU away from a CPU or migrate a new VCPU onto a CPU, or when we return to userspace to capture the state of the VCPU for migration. To make sure this works, factor out the APR save/restore functionality into separate functions called from the VCPU (and by extension VGIC) put/load hooks. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Handle VGICv3 save/restore from the main VGIC code on VHEChristoffer Dall2-2/+20
Just like we can program the GICv2 hypervisor control interface directly from the core vgic code, we can do the same for the GICv3 hypervisor control interface on VHE systems. We do this by simply calling the save/restore functions when we have VHE and we can then get rid of the save/restore function calls from the VHE world switch function. One caveat is that we now write GICv3 system register state before the potential early exit path in the run loop, and because we sync back state in the early exit path, we have to ensure that we read a consistent GIC state from the sync path, even though we have never actually run the guest with the newly written GIC state. We solve this by inserting an ISB in the early exit path. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move arm64-only vgic-v2-sr.c file to arm64Christoffer Dall1-80/+0
The vgic-v2-sr.c file now only contains the logic to replay unaligned accesses to the virtual CPU interface on 16K and 64K page systems, which is only relevant on 64-bit platforms. Therefore move this file to the arm64 KVM tree, remove the compile directive from the 32-bit side makefile, and remove the ifdef in the C file. Since this file also no longer saves/restores anything, rename the file to vgic-v2-cpuif-proxy.c to more accurately describe the logic in this file. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Handle VGICv2 save/restore from the main VGIC codeChristoffer Dall4-66/+84
We can program the GICv2 hypervisor control interface logic directly from the core vgic code and can instead do the save/restore directly from the flush/sync functions, which can lead to a number of future optimizations. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Get rid of vgic_elrsrChristoffer Dall4-26/+10
There is really no need to store the vgic_elrsr on the VGIC data structures as the only need we have for the elrsr is to figure out if an LR is inactive when we save the VGIC state upon returning from the guest. We can might as well store this in a temporary local variable. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Prepare to handle deferred save/restore of SPSR_EL1Christoffer Dall1-1/+1
SPSR_EL1 is not used by a VHE host kernel and can be deferred, but we need to rework the accesses to this register to access the latest value depending on whether or not guest system registers are loaded on the CPU or only reside in memory. The handling of accessing the various banked SPSRs for 32-bit VMs is a bit clunky, but this will be improved in following patches which will first prepare and subsequently implement deferred save/restore of the 32-bit registers, including the 32-bit SPSRs. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm64: Rewrite system register accessors to read/write functionsChristoffer Dall1-18/+18
Currently we access the system registers array via the vcpu_sys_reg() macro. However, we are about to change the behavior to some times modify the register file directly, so let's change this to two primitives: * Accessor macros vcpu_write_sys_reg() and vcpu_read_sys_reg() * Direct array access macro __vcpu_sys_reg() The accessor macros should be used in places where the code needs to access the currently loaded VCPU's state as observed by the guest. For example, when trapping on cache related registers, a write to a system register should go directly to the VCPU version of the register. The direct array access macro can be used in places where the VCPU is known to never be running (for example userspace access) or for registers which are never context switched (for example all the PMU system registers). This rewrites all users of vcpu_sys_regs to one of the macros described above. No functional change. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm64: Remove noop calls to timer save/restore from VHE switchChristoffer Dall1-22/+22
The VHE switch function calls __timer_enable_traps and __timer_disable_traps which don't do anything on VHE systems. Therefore, simply remove these calls from the VHE switch function and make the functions non-conditional as they are now only called from the non-VHE switch path. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm64: Introduce VHE-specific kvm_vcpu_runChristoffer Dall1-5/+7
So far this is mostly (see below) a copy of the legacy non-VHE switch function, but we will start reworking these functions in separate directions to work on VHE and non-VHE in the most optimal way in later patches. The only difference after this patch between the VHE and non-VHE run functions is that we omit the branch-predictor variant-2 hardening for QC Falkor CPUs, because this workaround is specific to a series of non-VHE ARMv8.0 CPUs. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Add kvm_vcpu_load_sysregs and kvm_vcpu_put_sysregsChristoffer Dall1-0/+2
As we are about to move a bunch of save/restore logic for VHE kernels to the load and put functions, we need some infrastructure to do this. Reviewed-by: Andrew Jones <drjones@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Get rid of vcpu->arch.irq_linesChristoffer Dall2-8/+9
We currently have a separate read-modify-write of the HCR_EL2 on entry to the guest for the sole purpose of setting the VF and VI bits, if set. Since this is most rarely the case (only when using userspace IRQ chip and interrupts are in flight), let's get rid of this operation and instead modify the bits in the vcpu->arch.hcr[_el2] directly when needed. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move vcpu_load call after kvm_vcpu_first_run_initChristoffer Dall3-29/+8
Moving the call to vcpu_load() in kvm_arch_vcpu_ioctl_run() to after we've called kvm_vcpu_first_run_init() simplifies some of the vgic and there is also no need to do vcpu_load() for things such as handling the immediate_exit flag. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Avoid vcpu_load for other vcpu ioctls than KVM_RUNChristoffer Dall1-9/+0
Calling vcpu_load() registers preempt notifiers for this vcpu and calls kvm_arch_vcpu_load(). The latter will soon be doing a lot of heavy lifting on arm/arm64 and will try to do things such as enabling the virtual timer and setting us up to handle interrupts from the timer hardware. Loading state onto hardware registers and enabling hardware to signal interrupts can be problematic when we're not actually about to run the VCPU, because it makes it difficult to establish the right context when handling interrupts from the timer, and it makes the register access code difficult to reason about. Luckily, now when we call vcpu_load in each ioctl implementation, we can simply remove the call from the non-KVM_RUN vcpu ioctls, and our kvm_arch_vcpu_load() is only used for loading vcpu content to the physical CPU when we're actually going to run the vcpu. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14kvm: arm/arm64: vgic-v3: Tighten synchronization for guests using v2 on v3Marc Zyngier1-1/+2
On guest exit, and when using GICv2 on GICv3, we use a dsb(st) to force synchronization between the memory-mapped guest view and the system-register view that the hypervisor uses. This is incorrect, as the spec calls out the need for "a DSB whose required access type is both loads and stores with any Shareability attribute", while we're only synchronizing stores. We also lack an isb after the dsb to ensure that the latter has actually been executed before we start reading stuff from the sysregs. The fix is pretty easy: turn dsb(st) into dsb(sy), and slap an isb() just after. Cc: stable@vger.kernel.org Fixes: f68d2b1b73cc ("arm64: KVM: Implement vgic-v3 save/restore") Acked-by: Christoffer Dall <cdall@kernel.org> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintidMarc Zyngier4-16/+65
The vgic code is trying to be clever when injecting GICv2 SGIs, and will happily populate LRs with the same interrupt number if they come from multiple vcpus (after all, they are distinct interrupt sources). Unfortunately, this is against the letter of the architecture, and the GICv2 architecture spec says "Each valid interrupt stored in the List registers must have a unique VirtualID for that virtual CPU interface.". GICv3 has similar (although slightly ambiguous) restrictions. This results in guests locking up when using GICv2-on-GICv3, for example. The obvious fix is to stop trying so hard, and inject a single vcpu per SGI per guest entry. After all, pending SGIs with multiple source vcpus are pretty rare, and are mostly seen in scenario where the physical CPUs are severely overcomitted. But as we now only inject a single instance of a multi-source SGI per vcpu entry, we may delay those interrupts for longer than strictly necessary, and run the risk of injecting lower priority interrupts in the meantime. In order to address this, we adopt a three stage strategy: - If we encounter a multi-source SGI in the AP list while computing its depth, we force the list to be sorted - When populating the LRs, we prevent the injection of any interrupt of lower priority than that of the first multi-source SGI we've injected. - Finally, the injection of a multi-source SGI triggers the request of a maintenance interrupt when there will be no pending interrupt in the LRs (HCR_NPIE). At the point where the last pending interrupt in the LRs switches from Pending to Active, the maintenance interrupt will be delivered, allowing us to add the remaining SGIs using the same process. Cc: stable@vger.kernel.org Fixes: 0919e84c0fc1 ("KVM: arm/arm64: vgic-new: Add IRQ sync/flush framework") Acked-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: Reduce verbosity of KVM init logArd Biesheuvel3-5/+5
On my GICv3 system, the following is printed to the kernel log at boot: kvm [1]: 8-bit VMID kvm [1]: IDMAP page: d20e35000 kvm [1]: HYP VA range: 800000000000:ffffffffffff kvm [1]: vgic-v2@2c020000 kvm [1]: GIC system register CPU interface enabled kvm [1]: vgic interrupt IRQ1 kvm [1]: virtual timer IRQ4 kvm [1]: Hyp mode initialized successfully The KVM IDMAP is a mapping of a statically allocated kernel structure, and so printing its physical address leaks the physical placement of the kernel when physical KASLR in effect. So change the kvm_info() to kvm_debug() to remove it from the log output. While at it, trim the output a bit more: IRQ numbers can be found in /proc/interrupts, and the HYP VA and vgic-v2 lines are not highly informational either. Cc: <stable@vger.kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: Reset mapped IRQs on VM resetChristoffer Dall2-0/+30
We currently don't allow resetting mapped IRQs from userspace, because their state is controlled by the hardware. But we do need to reset the state when the VM is reset, so we provide a function for the 'owner' of the mapped interrupt to reset the interrupt state. Currently only the timer uses mapped interrupts, so we call this function from the timer reset logic. Cc: stable@vger.kernel.org Fixes: 4c60e360d6df ("KVM: arm/arm64: Provide a get_input_level for the arch timer") Signed-off-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: Avoid vcpu_load for other vcpu ioctls than KVM_RUNChristoffer Dall1-9/+0
Calling vcpu_load() registers preempt notifiers for this vcpu and calls kvm_arch_vcpu_load(). The latter will soon be doing a lot of heavy lifting on arm/arm64 and will try to do things such as enabling the virtual timer and setting us up to handle interrupts from the timer hardware. Loading state onto hardware registers and enabling hardware to signal interrupts can be problematic when we're not actually about to run the VCPU, because it makes it difficult to establish the right context when handling interrupts from the timer, and it makes the register access code difficult to reason about. Luckily, now when we call vcpu_load in each ioctl implementation, we can simply remove the call from the non-KVM_RUN vcpu ioctls, and our kvm_arch_vcpu_load() is only used for loading vcpu content to the physical CPU when we're actually going to run the vcpu. Cc: stable@vger.kernel.org Fixes: 9b062471e52a ("KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl") Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14KVM: arm/arm64: vgic: Add missing irq_lock to vgic_mmio_read_pendingAndre Przywara2-0/+4
Our irq_is_pending() helper function accesses multiple members of the vgic_irq struct, so we need to hold the lock when calling it. Add that requirement as a comment to the definition and take the lock around the call in vgic_mmio_read_pending(), where we were missing it before. Fixes: 96b298000db4 ("KVM: arm/arm64: vgic-new: Add PENDING registers handlers") Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-06kvm: use insert sort in kvm_io_bus_register_dev functionGal Hammer1-18/+18
The loading time of a VM is quite significant with a CPU usage reaching 100% when loading a VM that its virtio devices use a large amount of virt-queues (e.g. a virtio-serial device with max_ports=511). Most of the time is spend in re-sorting the kvm_io_bus kvm_io_range array when a new eventfd is registered. The patch replaces the existing method with an insert sort. Reviewed-by: Marcel Apfelbaum <marcel@redhat.com> Reviewed-by: Uri Lublin <ulublin@redhat.com> Signed-off-by: Gal Hammer <ghammer@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>