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| | * | KVM: arm64: Allow creating the PMU without the in-kernel GICChristoffer Dall2017-06-082-12/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we got support for devices in userspace which allows reporting the PMU overflow output status to userspace, we should actually allow creating the PMU on systems without an in-kernel irqchip, which in turn requires us to slightly clarify error codes for the ABI and move things around for the initialization phase. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | KVM: arm/arm64: timer: remove request-less vcpu kickAndrew Jones2017-06-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The timer work is only scheduled for a VCPU when that VCPU is blocked. This means we only need to wake it up, not kick (IPI) it. While calling kvm_vcpu_kick() would just do the wake up, and not kick, anyway, let's change this to avoid request-less vcpu kicks, as they're generally not a good idea (see "Request-less VCPU Kicks" in Documentation/virtual/kvm/vcpu-requests.rst) Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: PMU: remove request-less vcpu kickAndrew Jones2017-06-041-21/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refactor PMU overflow handling in order to remove the request-less vcpu kick. Now, since kvm_vgic_inject_irq() uses vcpu requests, there should be no chance that a kick sent at just the wrong time (between the VCPU's call to kvm_pmu_flush_hwstate() and before it enters guest mode) results in a failure for the guest to see updated GIC state until its next exit some time later for some other reason. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: use vcpu requests for irq injectionAndrew Jones2017-06-042-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't use request-less VCPU kicks when injecting IRQs, as a VCPU kick meant to trigger the interrupt injection could be sent while the VCPU is outside guest mode, which means no IPI is sent, and after it has called kvm_vgic_flush_hwstate(), meaning it won't see the updated GIC state until its next exit some time later for some other reason. The receiving VCPU only needs to check this request in VCPU RUN to handle it. By checking it, if it's pending, a memory barrier will be issued that ensures all state is visible. See "Ensuring Requests Are Seen" of Documentation/virtual/kvm/vcpu-requests.rst Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: change exit request to sleep requestAndrew Jones2017-06-042-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A request called EXIT is too generic. All requests are meant to cause exits, but different requests have different flags. Let's not make it difficult to decide if the EXIT request is correct for some case by just always providing unique requests for each case. This patch changes EXIT to SLEEP, because that's what the request is asking the VCPU to do. Signed-off-by: Andrew Jones <drjones@redhat.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: optimize VCPU RUNAndrew Jones2017-06-042-8/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can make a small optimization by not checking the state of the power_off field on each run. This is done by treating power_off like pause, only checking it when we get the EXIT VCPU request. When a VCPU powers off another VCPU the EXIT request is already made, so we just need to make sure the request is also made on self power off. kvm_vcpu_kick() isn't necessary for these cases, as the VCPU would just be kicking itself, but we add it anyway as a self kick doesn't cost much, and it makes the code more future-proof. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: use vcpu requests for power_offAndrew Jones2017-06-041-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | System shutdown is currently using request-less VCPU kicks. This leaves open a tiny race window, as it doesn't ensure the state change to power_off is seen by a VCPU just about to enter guest mode. VCPU requests, OTOH, are guaranteed to be seen (see "Ensuring Requests Are Seen" of Documentation/virtual/kvm/vcpu-requests.rst) This patch applies the EXIT request used by pause to power_off, fixing the race. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: replace pause checks with vcpu request checksAndrew Jones2017-06-041-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current use of KVM_REQ_VCPU_EXIT for pause is fine. Even the requester clearing the request is OK, as this is the special case where the sole requesting thread and receiving VCPU are executing synchronously (see "Clearing Requests" in Documentation/virtual/kvm/vcpu-requests.rst) However, that's about to change, so let's ensure only the receiving VCPU clears the request. Additionally, by guaranteeing KVM_REQ_VCPU_EXIT is always set when pause is, we can avoid checking pause directly in VCPU RUN. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: properly use vcpu requestsAndrew Jones2017-06-042-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arm/arm64 already has one VCPU request used when setting pause, but it doesn't properly check requests in VCPU RUN. Check it and also make sure we set vcpu->mode at the appropriate time (before the check) and with the appropriate barriers. See Documentation/virtual/kvm/vcpu-requests.rst. Also make sure we don't leave any vcpu requests we don't intend to handle later set in the request bitmap. If we don't clear them, then kvm_request_pending() may return true when it shouldn't. Using VCPU requests properly fixes a small race where pause could get set just as a VCPU was entering guest mode. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: Use uaccess functions for GICv3 {sc}activeChristoffer Dall2017-06-041-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We recently rewrote the sactive and cactive handlers to take the kvm lock for guest accesses to these registers. However, when accessed from userspace this lock is already held. Unfortunately we forgot to change the private accessors for GICv3, because these are redistributor registers and not distributor registers. Signed-off-by: Christoffer Dall <cdall@linaro.org>
| | * | KVM: arm/arm64: Simplify active_change_prepare and plug raceChristoffer Dall2017-05-233-29/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't need to stop a specific VCPU when changing the active state, because private IRQs can only be modified by a running VCPU for the VCPU itself and it is therefore already stopped. However, it is also possible for two VCPUs to be modifying the active state of SPIs at the same time, which can cause the thread being stuck in the loop that checks other VCPU threads for a potentially very long time, or to modify the active state of a running VCPU. Fix this by serializing all accesses to setting and clearing the active state of interrupts using the KVM mutex. Reported-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | KVM: arm/arm64: Separate guest and uaccess writes to dist {sc}activeChristoffer Dall2017-05-234-12/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Factor out the core register modifier functionality from the entry points from the register description table, and only call the prepare/finish functions from the guest path, not the uaccess path. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | KVM: arm/arm64: Allow GICv2 to supply a uaccess register functionChristoffer Dall2017-05-232-12/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are about to differentiate between writes from a VCPU and from userspace to the GIC's GICD_ISACTIVER and GICD_ICACTIVER registers due to different synchronization requirements. Expand the macro to define a register description for the GIC to take uaccess functions as well. Signed-off-by: Christoffer Dall <cdall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
| * | | KVM: explain missing kvm_put_kvm in case of failurePaolo Bonzini2017-06-271-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The call to kvm_put_kvm was removed from error handling in commit 506cfba9e726 ("KVM: don't use anon_inode_getfd() before possible failures"), but it is _not_ a memory leak. Reuse Al's explanation to avoid that someone else makes the same mistake. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | KVM: Replaces symbolic permissions with numericRoman Storozhenko2017-06-271-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replaces "S_IRUGO | S_IWUSR" with 0644. The reason is that symbolic permissions considered harmful: https://lwn.net/Articles/696229/ Signed-off-by: Roman Storozhenko <romeusmeister@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | | Merge tag 'arm64-upstream' of ↵Linus Torvalds2017-07-051-3/+33
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - RAS reporting via GHES/APEI (ACPI) - Indirect ftrace trampolines for modules - Improvements to kernel fault reporting - Page poisoning - Sigframe cleanups and preparation for SVE context - Core dump fixes - Sparse fixes (mainly relating to endianness) - xgene SoC PMU v3 driver - Misc cleanups and non-critical fixes * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (75 commits) arm64: fix endianness annotation for 'struct jit_ctx' and friends arm64: cpuinfo: constify attribute_group structures. arm64: ptrace: Fix incorrect get_user() use in compat_vfp_set() arm64: ptrace: Remove redundant overrun check from compat_vfp_set() arm64: ptrace: Avoid setting compat FP[SC]R to garbage if get_user fails arm64: fix endianness annotation for __apply_alternatives()/get_alt_insn() arm64: fix endianness annotation in get_kaslr_seed() arm64: add missing conversion to __wsum in ip_fast_csum() arm64: fix endianness annotation in acpi_parking_protocol.c arm64: use readq() instead of readl() to read 64bit entry_point arm64: fix endianness annotation for reloc_insn_movw() & reloc_insn_imm() arm64: fix endianness annotation for aarch64_insn_write() arm64: fix endianness annotation in aarch64_insn_read() arm64: fix endianness annotation in call_undef_hook() arm64: fix endianness annotation for debug-monitors.c ras: mark stub functions as 'inline' arm64: pass endianness info to sparse arm64: ftrace: fix !CONFIG_ARM64_MODULE_PLTS kernels arm64: signal: Allow expansion of the signal frame acpi: apei: check for pending errors when probing GHES entries ...
| * | | | arm/arm64: KVM: add guest SEA supportTyler Baicar2017-06-221-3/+33
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently external aborts are unsupported by the guest abort handling. Add handling for SEAs so that the host kernel reports SEAs which occur in the guest kernel. When an SEA occurs in the guest kernel, the guest exits and is routed to kvm_handle_guest_abort(). Prior to this patch, a print message of an unsupported FSC would be printed and nothing else would happen. With this patch, the code gets routed to the APEI handling of SEAs in the host kernel to report the SEA information. Signed-off-by: Tyler Baicar <tbaicar@codeaurora.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
* | | / sched/wait: Rename wait_queue_t => wait_queue_entry_tIngo Molnar2017-06-201-1/+1
| |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename: wait_queue_t => wait_queue_entry_t 'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue", but in reality it's a queue *entry*. The 'real' queue is the wait queue head, which had to carry the name. Start sorting this out by renaming it to 'wait_queue_entry_t'. This also allows the real structure name 'struct __wait_queue' to lose its double underscore and become 'struct wait_queue_entry', which is the more canonical nomenclature for such data types. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | KVM: arm/arm64: Handle possible NULL stage2 pud when ageing pagesMarc Zyngier2017-06-061-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Under memory pressure, we start ageing pages, which amounts to parsing the page tables. Since we don't want to allocate any extra level, we pass NULL for our private allocation cache. Which means that stage2_get_pud() is allowed to fail. This results in the following splat: [ 1520.409577] Unable to handle kernel NULL pointer dereference at virtual address 00000008 [ 1520.417741] pgd = ffff810f52fef000 [ 1520.421201] [00000008] *pgd=0000010f636c5003, *pud=0000010f56f48003, *pmd=0000000000000000 [ 1520.429546] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 1520.435156] Modules linked in: [ 1520.438246] CPU: 15 PID: 53550 Comm: qemu-system-aar Tainted: G W 4.12.0-rc4-00027-g1885c397eaec #7205 [ 1520.448705] Hardware name: FOXCONN R2-1221R-A4/C2U4N_MB, BIOS G31FB12A 10/26/2016 [ 1520.463726] task: ffff800ac5fb4e00 task.stack: ffff800ce04e0000 [ 1520.469666] PC is at stage2_get_pmd+0x34/0x110 [ 1520.474119] LR is at kvm_age_hva_handler+0x44/0xf0 [ 1520.478917] pc : [<ffff0000080b137c>] lr : [<ffff0000080b149c>] pstate: 40000145 [ 1520.486325] sp : ffff800ce04e33d0 [ 1520.489644] x29: ffff800ce04e33d0 x28: 0000000ffff40064 [ 1520.494967] x27: 0000ffff27e00000 x26: 0000000000000000 [ 1520.500289] x25: ffff81051ba65008 x24: 0000ffff40065000 [ 1520.505618] x23: 0000ffff40064000 x22: 0000000000000000 [ 1520.510947] x21: ffff810f52b20000 x20: 0000000000000000 [ 1520.516274] x19: 0000000058264000 x18: 0000000000000000 [ 1520.521603] x17: 0000ffffa6fe7438 x16: ffff000008278b70 [ 1520.526940] x15: 000028ccd8000000 x14: 0000000000000008 [ 1520.532264] x13: ffff7e0018298000 x12: 0000000000000002 [ 1520.537582] x11: ffff000009241b93 x10: 0000000000000940 [ 1520.542908] x9 : ffff0000092ef800 x8 : 0000000000000200 [ 1520.548229] x7 : ffff800ce04e36a8 x6 : 0000000000000000 [ 1520.553552] x5 : 0000000000000001 x4 : 0000000000000000 [ 1520.558873] x3 : 0000000000000000 x2 : 0000000000000008 [ 1520.571696] x1 : ffff000008fd5000 x0 : ffff0000080b149c [ 1520.577039] Process qemu-system-aar (pid: 53550, stack limit = 0xffff800ce04e0000) [...] [ 1521.510735] [<ffff0000080b137c>] stage2_get_pmd+0x34/0x110 [ 1521.516221] [<ffff0000080b149c>] kvm_age_hva_handler+0x44/0xf0 [ 1521.522054] [<ffff0000080b0610>] handle_hva_to_gpa+0xb8/0xe8 [ 1521.527716] [<ffff0000080b3434>] kvm_age_hva+0x44/0xf0 [ 1521.532854] [<ffff0000080a58b0>] kvm_mmu_notifier_clear_flush_young+0x70/0xc0 [ 1521.539992] [<ffff000008238378>] __mmu_notifier_clear_flush_young+0x88/0xd0 [ 1521.546958] [<ffff00000821eca0>] page_referenced_one+0xf0/0x188 [ 1521.552881] [<ffff00000821f36c>] rmap_walk_anon+0xec/0x250 [ 1521.558370] [<ffff000008220f78>] rmap_walk+0x78/0xa0 [ 1521.563337] [<ffff000008221104>] page_referenced+0x164/0x180 [ 1521.569002] [<ffff0000081f1af0>] shrink_active_list+0x178/0x3b8 [ 1521.574922] [<ffff0000081f2058>] shrink_node_memcg+0x328/0x600 [ 1521.580758] [<ffff0000081f23f4>] shrink_node+0xc4/0x328 [ 1521.585986] [<ffff0000081f2718>] do_try_to_free_pages+0xc0/0x340 [ 1521.592000] [<ffff0000081f2a64>] try_to_free_pages+0xcc/0x240 [...] The trivial fix is to handle this NULL pud value early, rather than dereferencing it blindly. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | | KVM: arm/arm64: vgic-v3: Fix nr_pre_bits bitfield extractionChristoffer Dall2017-06-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We used to extract PRIbits from the ICH_VT_EL2 which was the upper field in the register word, so a mask wasn't necessary, but as we switched to looking at PREbits, which is bits 26 through 28 with the PRIbits field being potentially non-zero, we really need to mask off the field value, otherwise fun things may happen. Signed-off-by: Christoffer Dall <cdall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* | | KVM: arm/arm64: Fix isues with GICv2 on GICv3 migrationChristoffer Dall2017-05-244-23/+80
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have been a little loose with our intermediate VMCR representation where we had a 'ctlr' field, but we failed to differentiate between the GICv2 GICC_CTLR and ICC_CTLR_EL1 layouts, and therefore ended up mapping the wrong bits into the individual fields of the ICH_VMCR_EL2 when emulating a GICv2 on a GICv3 system. Fix this by using explicit fields for the VMCR bits instead. Cc: Eric Auger <eric.auger@redhat.com> Reported-by: wanghaibin <wanghaibin.wang@huawei.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com>
* | KVM: arm/arm64: Hold slots_lock when unregistering kvm io bus devicesChristoffer Dall2017-05-181-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | We were not holding the kvm->slots_lock as required when calling kvm_io_bus_unregister_dev() as required. This only affects the error path, but still, let's do our due diligence. Reported by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
* | KVM: arm/arm64: Fix bug when registering redist iodevsChristoffer Dall2017-05-182-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If userspace creates the VCPUs after initializing the VGIC, then we end up in a situation where we trigger a bug in kvm_vcpu_get_idx(), because it is called prior to adding the VCPU into the vcpus array on the VM. There is no tight coupling between the VCPU index and the area of the redistributor region used for the VCPU, so we can simply ensure that all creations of redistributors are serialized per VM, and increment an offset when we successfully add a redistributor. The vgic_register_redist_iodev() function can be called from two paths: vgic_redister_all_redist_iodev() which is called via the kvm_vgic_addr() device attribute handler. This patch already holds the kvm->lock mutex. The other path is via kvm_vgic_vcpu_init, which is called through a longer chain from kvm_vm_ioctl_create_vcpu(), which releases the kvm->lock mutex just before calling kvm_arch_vcpu_create(), so we can simply take this mutex again later for our purposes. Fixes: ab6f468c10 ("KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs") Signed-off-by: Christoffer Dall <cdall@linaro.org> Tested-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com>
* | kvm: arm/arm64: Fix use after free of stage2 page tableSuzuki K Poulose2017-05-161-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We yield the kvm->mmu_lock occassionaly while performing an operation (e.g, unmap or permission changes) on a large area of stage2 mappings. However this could possibly cause another thread to clear and free up the stage2 page tables while we were waiting for regaining the lock and thus the original thread could end up in accessing memory that was freed. This patch fixes the problem by making sure that the stage2 pagetable is still valid after we regain the lock. The fact that mmu_notifer->release() could be called twice (via __mmu_notifier_release and mmu_notifier_unregsister) enhances the possibility of hitting this race where there are two threads trying to unmap the entire guest shadow pages. While at it, cleanup the redudant checks around cond_resched_lock in stage2_wp_range(), as cond_resched_lock already does the same checks. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: andreyknvl@google.com Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: stable@vger.kernel.org Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | kvm: arm/arm64: Force reading uncached stage2 PGDSuzuki K Poulose2017-05-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | Make sure we don't use a cached value of the KVM stage2 PGD while resetting the PGD. Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | kvm: arm/arm64: Fix race in resetting stage2 PGDSuzuki K Poulose2017-05-151-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In kvm_free_stage2_pgd() we check the stage2 PGD before holding the lock and proceed to take the lock if it is valid. And we unmap the page tables, followed by releasing the lock. We reset the PGD only after dropping this lock, which could cause a race condition where another thread waiting on or even holding the lock, could potentially see that the PGD is still valid and proceed to perform a stage2 operation and later encounter a NULL PGD. [223090.242280] Unable to handle kernel NULL pointer dereference at virtual address 00000040 [223090.262330] PC is at unmap_stage2_range+0x8c/0x428 [223090.262332] LR is at kvm_unmap_hva_handler+0x2c/0x3c [223090.262531] Call trace: [223090.262533] [<ffff0000080adb78>] unmap_stage2_range+0x8c/0x428 [223090.262535] [<ffff0000080adf40>] kvm_unmap_hva_handler+0x2c/0x3c [223090.262537] [<ffff0000080ace2c>] handle_hva_to_gpa+0xb0/0x104 [223090.262539] [<ffff0000080af988>] kvm_unmap_hva+0x5c/0xbc [223090.262543] [<ffff0000080a2478>] kvm_mmu_notifier_invalidate_page+0x50/0x8c [223090.262547] [<ffff0000082274f8>] __mmu_notifier_invalidate_page+0x5c/0x84 [223090.262551] [<ffff00000820b700>] try_to_unmap_one+0x1d0/0x4a0 [223090.262553] [<ffff00000820c5c8>] rmap_walk+0x1cc/0x2e0 [223090.262555] [<ffff00000820c90c>] try_to_unmap+0x74/0xa4 [223090.262557] [<ffff000008230ce4>] migrate_pages+0x31c/0x5ac [223090.262561] [<ffff0000081f869c>] compact_zone+0x3fc/0x7ac [223090.262563] [<ffff0000081f8ae0>] compact_zone_order+0x94/0xb0 [223090.262564] [<ffff0000081f91c0>] try_to_compact_pages+0x108/0x290 [223090.262569] [<ffff0000081d5108>] __alloc_pages_direct_compact+0x70/0x1ac [223090.262571] [<ffff0000081d64a0>] __alloc_pages_nodemask+0x434/0x9f4 [223090.262572] [<ffff0000082256f0>] alloc_pages_vma+0x230/0x254 [223090.262574] [<ffff000008235e5c>] do_huge_pmd_anonymous_page+0x114/0x538 [223090.262576] [<ffff000008201bec>] handle_mm_fault+0xd40/0x17a4 [223090.262577] [<ffff0000081fb324>] __get_user_pages+0x12c/0x36c [223090.262578] [<ffff0000081fb804>] get_user_pages_unlocked+0xa4/0x1b8 [223090.262579] [<ffff0000080a3ce8>] __gfn_to_pfn_memslot+0x280/0x31c [223090.262580] [<ffff0000080a3dd0>] gfn_to_pfn_prot+0x4c/0x5c [223090.262582] [<ffff0000080af3f8>] kvm_handle_guest_abort+0x240/0x774 [223090.262584] [<ffff0000080b2bac>] handle_exit+0x11c/0x1ac [223090.262586] [<ffff0000080ab99c>] kvm_arch_vcpu_ioctl_run+0x31c/0x648 [223090.262587] [<ffff0000080a1d78>] kvm_vcpu_ioctl+0x378/0x768 [223090.262590] [<ffff00000825df5c>] do_vfs_ioctl+0x324/0x5a4 [223090.262591] [<ffff00000825e26c>] SyS_ioctl+0x90/0xa4 [223090.262595] [<ffff000008085d84>] el0_svc_naked+0x38/0x3c This patch moves the stage2 PGD manipulation under the lock. Reported-by: Alexander Graf <agraf@suse.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | KVM: arm/arm64: vgic-v3: Use PREbits to infer the number of ICH_APxRn_EL2 ↵Marc Zyngier2017-05-151-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | registers The GICv3 documentation is extremely confusing, as it talks about the number of priorities represented by the ICH_APxRn_EL2 registers, while it should really talk about the number of preemption levels. This leads to a bug where we may access undefined ICH_APxRn_EL2 registers, since PREbits is allowed to be smaller than PRIbits. Thankfully, nobody seem to have taken this path so far... The fix is to use ICH_VTR_EL2.PREbits instead. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | KVM: arm/arm64: vgic-v3: Do not use Active+Pending state for a HW interruptMarc Zyngier2017-05-151-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When an interrupt is injected with the HW bit set (indicating that deactivation should be propagated to the physical distributor), special care must be taken so that we never mark the corresponding LR with the Active+Pending state (as the pending state is kept in the physycal distributor). Cc: stable@vger.kernel.org Fixes: 59529f69f504 ("KVM: arm/arm64: vgic-new: Add GICv3 world switch backend") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* | KVM: arm/arm64: vgic-v2: Do not use Active+Pending state for a HW interruptMarc Zyngier2017-05-151-0/+7
|/ | | | | | | | | | | | | | When an interrupt is injected with the HW bit set (indicating that deactivation should be propagated to the physical distributor), special care must be taken so that we never mark the corresponding LR with the Active+Pending state (as the pending state is kept in the physycal distributor). Cc: stable@vger.kernel.org Fixes: 140b086dd197 ("KVM: arm/arm64: vgic-new: Add GICv2 world switch backend") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
* Merge tag 'kvm-arm-for-v4.12-round2' of ↵Paolo Bonzini2017-05-0916-277/+5725
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD Second round of KVM/ARM Changes for v4.12. Changes include: - A fix related to the 32-bit idmap stub - A fix to the bitmask used to deode the operands of an AArch32 CP instruction - We have moved the files shared between arch/arm/kvm and arch/arm64/kvm to virt/kvm/arm - We add support for saving/restoring the virtual ITS state to userspace
| * KVM: arm/arm64: vgic-its: Cleanup after failed ITT restoreChristoffer Dall2017-05-091-13/+22
| | | | | | | | | | | | | | | | | | | | | | When failing to restore the ITT for a DTE, we should remove the failed device entry from the list and free the object. We slightly refactor vgic_its_destroy to be able to reuse the now separate vgic_its_free_dte() function. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Don't call map_resources when restoring ITS tablesChristoffer Dall2017-05-091-9/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The only reason we called kvm_vgic_map_resources() when restoring the ITS tables was because we wanted to have the KVM iodevs registered in the KVM IO bus framework at the time when the ITS was restored such that a restored and active device can inject MSIs prior to otherwise calling kvm_vgic_map_resources() from the first run of a VCPU. Since we now register the KVM iodevs for the redestributors and ITS as soon as possible (when setting the base addresses), we no longer need this call and kvm_vgic_map_resources() is again called only when first running a VCPU. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Register ITS iodev when setting base addressChristoffer Dall2017-05-093-43/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have to register the ITS iodevice before running the VM, because in migration scenarios, we may be restoring a live device that wishes to inject MSIs before the VCPUs have started. All we need to register the ITS io device is the base address of the ITS, so we can simply register that when the base address of the ITS is set. [ Code to fix concurrency issues when setting the ITS base address and to fix the undef base address check written by Marc Zyngier ] Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Get rid of its->initialized fieldMarc Zyngier2017-05-091-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The its->initialized doesn't bring much to the table, and creates unnecessary ordering between setting the address and initializing it (which amounts to exactly nothing). Let's kill it altogether, making KVM_DEV_ARM_VGIC_CTRL_INIT the no-op it deserves to be. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUsChristoffer Dall2017-05-096-11/+71
| | | | | | | | | | | | | | | | | | | | | | | | Instead of waiting with registering KVM iodevs until the first VCPU is run, we can actually create the iodevs when the redist base address is set. The only downside is that we must now also check if we need to do this for VCPUs which are created after creating the VGIC, because there is no enforced ordering between creating the VGIC (and setting its base addresses) and creating the VCPUs. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Slightly rework kvm_vgic_addrChristoffer Dall2017-05-091-9/+13
| | | | | | | | | | | | | | | | | | | | As we are about to handle setting the address for the redistributor base region separately from some of the other base addresses, let's rework this function to leave a little more room for being flexible in what each type of base address does. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Make vgic_v3_check_base more broadly usableChristoffer Dall2017-05-092-4/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we are about to fiddle with the IO device registration mechanism, let's be a little more careful when setting base addresses as early as possible. When setting a base address, we can check that there's address space enough for its scope and when the last of the two base addresses (dist and redist) get set, we can also check if the regions overlap at that time. This allows us to provide error messages to the user at time when trying to set the base address, as opposed to later when trying to run the VM. To do this, we make vgic_v3_check_base available in the core vgic-v3 code as well as in the other parts of the GICv3 code, namely the MMIO config code. We also return true for undefined base addresses so that the function can be used before all base addresses are set; all callers already check for uninitialized addresses before calling this function. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: Refactor vgic_register_redist_iodevsChristoffer Dall2017-05-093-44/+68
| | | | | | | | | | | | | | | | | | Split out the function to register all the redistributor iodevs into a function that handles a single redistributor at a time in preparation for being able to call this per VCPU as these get created. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm/arm64: vgic: Rename kvm_vgic_vcpu_init to kvm_vgic_vcpu_enableChristoffer Dall2017-05-091-6/+2
| | | | | | | | | | | | | | | | | | This function really doesn't init anything, it enables the CPU interface, so name it as such, which gives us the name to use for actual init work later on. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
| * KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLESEric Auger2017-05-083-0/+72
| | | | | | | | | | | | | | | | | | | | This patch adds a new attribute to GICV3 KVM device KVM_DEV_ARM_VGIC_GRP_CTRL group. This allows userspace to flush all GICR pending tables into guest RAM. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: Fix pending table syncEric Auger2017-05-081-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In its_sync_lpi_pending_table() we currently ignore the target_vcpu of the LPIs. We sync the pending bit found in the vcpu pending table even if the LPI is not targeting it. Also in vgic_its_cmd_handle_invall() we are supposed to read the config table data for the LPIs associated to the collection ID. At the moment we refresh all LPI config information. This patch passes a vpcu to vgic_copy_lpi_list() so that this latter returns a snapshot of the LPIs targeting this CPU and only those. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: ITT save and restoreEric Auger2017-05-082-3/+117
| | | | | | | | | | | | | | | | Implement routines to save and restore device ITT and their interrupt table entries (ITE). Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org>
| * KVM: arm64: vgic-its: Device table save/restoreEric Auger2017-05-082-5/+199
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch saves the device table entries into guest RAM. Both flat table and 2 stage tables are supported. DeviceId indexing is used. For each device listed in the device table, we also save the translation table using the vgic_its_save/restore_itt routines. Those functions will be implemented in a subsequent patch. On restore, devices are re-allocated and their itt are re-built. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org>
| * KVM: arm64: vgic-its: vgic_its_check_id returns the entry's GPAEric Auger2017-05-081-3/+8
| | | | | | | | | | | | | | | | | | As vgic_its_check_id() computes the device/collection entry's GPA, let's return it so that new callers can retrieve it easily. Signed-off-by: Eric Auger <eric.auger@redhat.com> Acked-by: Christoffer Dall <cdall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: Collection table save/restoreEric Auger2017-05-082-2/+107
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The save path copies the collection entries into guest RAM at the GPA specified in the BASER register. This obviously requires the BASER to be set. The last written element is a dummy collection table entry. We do not index by collection ID as the collection entry can fit into 8 bytes while containing the collection ID. On restore path we re-allocate the collection objects. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: Add infrastructure for table lookupEric Auger2017-05-081-0/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a generic scan_its_table() helper whose role consists in scanning a contiguous table located in guest RAM and applying a callback on each entry. Entries can be handled as linked lists since the callback may return an id offset to the next entry and also indicate whether the entry is the last one. Helper functions also are added to compute the device/event ID offset to the next DTE/ITE. compute_next_devid_offset, compute_next_eventid_offset and scan_table will become static in subsequent patches Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: vgic_its_alloc_ite/deviceEric Auger2017-05-081-21/+47
| | | | | | | | | | | | | | | | | | Add two new helpers to allocate an its ite and an its device. This will avoid duplication on restore path. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
| * KVM: arm64: vgic-its: KVM_DEV_ARM_ITS_SAVE/RESTORE_TABLESEric Auger2017-05-081-4/+103
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce new attributes in KVM_DEV_ARM_VGIC_GRP_CTRL group: - KVM_DEV_ARM_ITS_SAVE_TABLES: saves the ITS tables into guest RAM - KVM_DEV_ARM_ITS_RESTORE_TABLES: restores them into VGIC internal structures. We hold the vcpus lock during the save and restore to make sure no vcpu is running. At this stage the functionality is not yet implemented. Only the skeleton is put in place. Signed-off-by: Eric Auger <eric.auger@redhat.com> [Given we will move the iodev register until setting the base addr] Reviewed-by: Christoffer Dall <cdall@linaro.org>
| * KVM: arm64: vgic-its: Read config and pending bit in add_lpi()Eric Auger2017-05-081-11/+24
| | | | | | | | | | | | | | | | | | When creating the lpi we now ask the redistributor what is the state of the LPI (priority, enabled, pending). Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org>
| * KVM: arm64: vgic-v3: vgic_v3_lpi_sync_pending_statusEric Auger2017-05-083-4/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this new helper synchronizes the irq pending_latch with the LPI pending bit status found in rdist pending table. As the status is consumed, we reset the bit in pending table. As we need the PENDBASER_ADDRESS() in vgic-v3, let's move its definition in the irqchip header. We restore the full length of the field, ie [51:16]. Same for PROPBASER_ADDRESS with full field length of [51:12]. Signed-off-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 14:39:49 +0000