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2019-07-20KVM: Boost vCPUs that are delivering interruptsWanpeng Li1-4/+8
Inspired by commit 9cac38dd5d (KVM/s390: Set preempted flag during vcpu wakeup and interrupt delivery), we want to also boost not just lock holders but also vCPUs that are delivering interrupts. Most smp_call_function_many calls are synchronous, so the IPI target vCPUs are also good yield candidates. This patch introduces vcpu->ready to boost vCPUs during wakeup and interrupt delivery time; unlike s390 we do not reuse vcpu->preempted so that voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin, but vmx_vcpu_pi_put is not affected (VT-d PI handles voluntary preemption separately, in pi_pre_block). Testing on 80 HT 2 socket Xeon Skylake server, with 80 vCPUs VM 80GB RAM: ebizzy -M vanilla boosting improved 1VM 21443 23520 9% 2VM 2800 8000 180% 3VM 1800 3100 72% Testing on my Haswell desktop 8 HT, with 8 vCPUs VM 8GB RAM, two VMs, one running ebizzy -M, the other running 'stress --cpu 2': w/ boosting + w/o pv sched yield(vanilla) vanilla boosting improved 1570 4000 155% w/ boosting + w/ pv sched yield(vanilla) vanilla boosting improved 1844 5157 179% w/o boosting, perf top in VM: 72.33% [kernel] [k] smp_call_function_many 4.22% [kernel] [k] call_function_i 3.71% [kernel] [k] async_page_fault w/ boosting, perf top in VM: 38.43% [kernel] [k] smp_call_function_many 6.31% [kernel] [k] async_page_fault 6.13% libc-2.23.so [.] __memcpy_avx_unaligned 4.88% [kernel] [k] call_function_interrupt Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Marc Zyngier <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-07-12Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds6-120/+455
Pull KVM updates from Paolo Bonzini: "ARM: - support for chained PMU counters in guests - improved SError handling - handle Neoverse N1 erratum #1349291 - allow side-channel mitigation status to be migrated - standardise most AArch64 system register accesses to msr_s/mrs_s - fix host MPIDR corruption on 32bit - selftests ckleanups x86: - PMU event {white,black}listing - ability for the guest to disable host-side interrupt polling - fixes for enlightened VMCS (Hyper-V pv nested virtualization), - new hypercall to yield to IPI target - support for passing cstate MSRs through to the guest - lots of cleanups and optimizations Generic: - Some txt->rST conversions for the documentation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (128 commits) Documentation: virtual: Add toctree hooks Documentation: kvm: Convert cpuid.txt to .rst Documentation: virtual: Convert paravirt_ops.txt to .rst KVM: x86: Unconditionally enable irqs in guest context KVM: x86: PMU Event Filter kvm: x86: Fix -Wmissing-prototypes warnings KVM: Properly check if "page" is valid in kvm_vcpu_unmap KVM: arm/arm64: Initialise host's MPIDRs by reading the actual register KVM: LAPIC: Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane kvm: LAPIC: write down valid APIC registers KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_s KVM: doc: Add API documentation on the KVM_REG_ARM_WORKAROUNDS register KVM: arm/arm64: Add save/restore support for firmware workaround state arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests KVM: arm/arm64: Support chained PMU counters KVM: arm/arm64: Remove pmc->bitmask KVM: arm/arm64: Re-create event when setting counter value KVM: arm/arm64: Extract duplicated code to own function KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functions KVM: LAPIC: ARBPRI is a reserved register for x2APIC ...
2019-07-12arm64: switch to generic version of pte allocationMike Rapoport1-1/+1
The PTE allocations in arm64 are identical to the generic ones modulo the GFP flags. Using the generic pte_alloc_one() functions ensures that the user page tables are allocated with __GFP_ACCOUNT set. The arm64 definition of PGALLOC_GFP is removed and replaced with GFP_PGTABLE_USER for p[gum]d_alloc_one() for the user page tables and GFP_PGTABLE_KERNEL for the kernel page tables. The KVM memory cache is now using GFP_PGTABLE_USER. The mappings created with create_pgd_mapping() are now using GFP_PGTABLE_KERNEL. The conversion to the generic version of pte_free_kernel() removes the NULL check for pte. The pte_free() version on arm64 is identical to the generic one and can be simply dropped. [[email protected]: fix a bogus GFP flag in pgd_alloc()] Link: https://lore.kernel.org/r/[email protected]/ [and fix it more] Link: https://lore.kernel.org/linux-mm/20190617151252.GF16810@rapoport-lnx/ Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Cc: Albert Ou <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Anton Ivanov <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Guo Ren <[email protected]> Cc: Helge Deller <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Paul Burton <[email protected]> Cc: Ralf Baechle <[email protected]> Cc: Richard Kuo <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Russell King <[email protected]> Cc: Sam Creasey <[email protected]> Cc: Vincent Chen <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-07-11Merge tag 'kvm-arm-for-5.3' of ↵Paolo Bonzini31-443/+465
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for 5.3 - Add support for chained PMU counters in guests - Improve SError handling - Handle Neoverse N1 erratum #1349291 - Allow side-channel mitigation status to be migrated - Standardise most AArch64 system register accesses to msr_s/mrs_s - Fix host MPIDR corruption on 32bit
2019-07-10KVM: Properly check if "page" is valid in kvm_vcpu_unmapKarimAllah Ahmed1-1/+1
The field "page" is initialized to KVM_UNMAPPED_PAGE when it is not used (i.e. when the memory lives outside kernel control). So this check will always end up using kunmap even for memremap regions. Fixes: e45adf665a53 ("KVM: Introduce a new guest mapping API") Cc: [email protected] Signed-off-by: KarimAllah Ahmed <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-07-08KVM: arm/arm64: Initialise host's MPIDRs by reading the actual registerMarc Zyngier1-1/+2
As part of setting up the host context, we populate its MPIDR by using cpu_logical_map(). It turns out that contrary to arm64, cpu_logical_map() on 32bit ARM doesn't return the *full* MPIDR, but a truncated version. This leaves the host MPIDR slightly corrupted after the first run of a VM, since we won't correctly restore the MPIDR on exit. Oops. Since we cannot trust cpu_logical_map(), let's adopt a different strategy. We move the initialization of the host CPU context as part of the per-CPU initialization (which, in retrospect, makes a lot of sense), and directly read the MPIDR from the HW. This is guaranteed to work on both arm and arm64. Reported-by: Andre Przywara <[email protected]> Tested-by: Andre Przywara <[email protected]> Fixes: 32f139551954 ("arm/arm64: KVM: Statically configure the host's view of MPIDR") Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_sDave Martin1-12/+12
Currently, the {read,write}_sysreg_el*() accessors for accessing particular ELs' sysregs in the presence of VHE rely on some local hacks and define their system register encodings in a way that is inconsistent with the core definitions in <asm/sysreg.h>. As a result, it is necessary to add duplicate definitions for any system register that already needs a definition in sysreg.h for other reasons. This is a bit of a maintenance headache, and the reasons for the _el*() accessors working the way they do is a bit historical. This patch gets rid of the shadow sysreg definitions in <asm/kvm_hyp.h>, converts the _el*() accessors to use the core __msr_s/__mrs_s interface, and converts all call sites to use the standard sysreg #define names (i.e., upper case, with SYS_ prefix). This patch will conflict heavily anyway, so the opportunity to clean up some bad whitespace in the context of the changes is taken. The change exposes a few system registers that have no sysreg.h definition, due to msr_s/mrs_s being used in place of msr/mrs: additions are made in order to fill in the gaps. Signed-off-by: Dave Martin <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoffer Dall <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Will Deacon <[email protected]> Link: https://www.spinics.net/lists/kvm-arm/msg31717.html [Rebased to v4.21-rc1] Signed-off-by: Sudeep Holla <[email protected]> [Rebased to v5.2-rc5, changelog updates] Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Add save/restore support for firmware workaround stateAndre Przywara1-15/+124
KVM implements the firmware interface for mitigating cache speculation vulnerabilities. Guests may use this interface to ensure mitigation is active. If we want to migrate such a guest to a host with a different support level for those workarounds, migration might need to fail, to ensure that critical guests don't loose their protection. Introduce a way for userland to save and restore the workarounds state. On restoring we do checks that make sure we don't downgrade our mitigation level. Signed-off-by: Andre Przywara <[email protected]> Reviewed-by: Eric Auger <[email protected]> Reviewed-by: Steven Price <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05arm64: KVM: Propagate full Spectre v2 workaround state to KVM guestsAndre Przywara1-1/+9
Recent commits added the explicit notion of "workaround not required" to the state of the Spectre v2 (aka. BP_HARDENING) workaround, where we just had "needed" and "unknown" before. Export this knowledge to the rest of the kernel and enhance the existing kvm_arm_harden_branch_predictor() to report this new state as well. Export this new state to guests when they use KVM's firmware interface emulation. Signed-off-by: Andre Przywara <[email protected]> Reviewed-by: Steven Price <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Support chained PMU countersAndrew Murray1-37/+215
ARMv8 provides support for chained PMU counters, where an event type of 0x001E is set for odd-numbered counters, the event counter will increment by one for each overflow of the preceding even-numbered counter. Let's emulate this in KVM by creating a 64 bit perf counter when a user chains two emulated counters together. For chained events we only support generating an overflow interrupt on the high counter. We use the attributes of the low counter to determine the attributes of the perf event. Suggested-by: Marc Zyngier <[email protected]> Signed-off-by: Andrew Murray <[email protected]> Reviewed-by: Julien Thierry <[email protected]> Reviewed-by: Suzuki K Poulose <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Remove pmc->bitmaskAndrew Murray1-10/+20
We currently use pmc->bitmask to determine the width of the pmc - however it's superfluous as the pmc index already describes if the pmc is a cycle counter or event counter. The architecture clearly describes the widths of these counters. Let's remove the bitmask to simplify the code. Signed-off-by: Andrew Murray <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Re-create event when setting counter valueAndrew Murray1-9/+33
The perf event sample_period is currently set based upon the current counter value, when PMXEVTYPER is written to and the perf event is created. However the user may choose to write the type before the counter value in which case sample_period will be set incorrectly. Let's instead decouple event creation from PMXEVTYPER and (re)create the event in either suitation. Signed-off-by: Andrew Murray <[email protected]> Reviewed-by: Julien Thierry <[email protected]> Reviewed-by: Suzuki K Poulose <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Extract duplicated code to own functionAndrew Murray1-12/+16
Let's reduce code duplication by extracting common code to its own function. Signed-off-by: Andrew Murray <[email protected]> Reviewed-by: Suzuki K Poulose <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-07-05KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functionsAndrew Murray1-6/+6
The kvm_pmu_{enable/disable}_counter functions can enable/disable multiple counters at once as they operate on a bitmask. Let's make this clearer by renaming the function. Suggested-by: Suzuki K Poulose <[email protected]> Signed-off-by: Andrew Murray <[email protected]> Reviewed-by: Julien Thierry <[email protected]> Reviewed-by: Suzuki K Poulose <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-06-21Merge tag 'spdx-5.2-rc6' of ↵Linus Torvalds22-244/+22
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull still more SPDX updates from Greg KH: "Another round of SPDX updates for 5.2-rc6 Here is what I am guessing is going to be the last "big" SPDX update for 5.2. It contains all of the remaining GPLv2 and GPLv2+ updates that were "easy" to determine by pattern matching. The ones after this are going to be a bit more difficult and the people on the spdx list will be discussing them on a case-by-case basis now. Another 5000+ files are fixed up, so our overall totals are: Files checked: 64545 Files with SPDX: 45529 Compared to the 5.1 kernel which was: Files checked: 63848 Files with SPDX: 22576 This is a huge improvement. Also, we deleted another 20000 lines of boilerplate license crud, always nice to see in a diffstat" * tag 'spdx-5.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: (65 commits) treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 507 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 506 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 505 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 504 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 503 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 502 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 501 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 498 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 496 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 495 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 491 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 490 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 489 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 488 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 487 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 486 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 485 ...
2019-06-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2-2/+4
Pull kvm fixes from Paolo Bonzini: "Fixes for ARM and x86, plus selftest patches and nicer structs for nested state save/restore" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: nVMX: reorganize initial steps of vmx_set_nested_state KVM: arm/arm64: Fix emulated ptimer irq injection tests: kvm: Check for a kernel warning kvm: tests: Sort tests in the Makefile alphabetically KVM: x86/mmu: Allocate PAE root array when using SVM's 32-bit NPT KVM: x86: Modify struct kvm_nested_state to have explicit fields for data KVM: fix typo in documentation KVM: nVMX: use correct clean fields when copying from eVMCS KVM: arm/arm64: vgic: Fix kvm_device leak in vgic_its_destroy KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST KVM: arm64: Implement vq_present() as a macro
2019-06-20Merge tag 'kvmarm-fixes-for-5.2-2' of ↵Paolo Bonzini2-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm fixes for 5.2, take #2 - SVE cleanup killing a warning with ancient GCC versions - Don't report non-existent system registers to userspace - Fix memory leak when freeing the vgic ITS - Properly lower the interrupt on the emulated physical timer
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 504Thomas Gleixner3-39/+3
Based on 1 normalized pattern(s): this file is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 8 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2-8/+2
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Allison Randal <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499Thomas Gleixner1-4/+1
Based on 1 normalized pattern(s): this work is licensed under the terms of the gnu gpl version 2 see the copying file in the top level directory extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 35 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Reviewed-by: Allison Randal <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner16-193/+16
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Alexios Zavras <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-19KVM: arm/arm64: Fix emulated ptimer irq injectionAndrew Jones1-2/+3
The emulated ptimer needs to track the level changes, otherwise the the interrupt will never get deasserted, resulting in the guest getting stuck in an interrupt storm if it enables ptimer interrupts. This was found with kvm-unit-tests; the ptimer tests hung as soon as interrupts were enabled. Typical Linux guests don't have a problem as they prefer using the virtual timer. Fixes: bee038a674875 ("KVM: arm/arm64: Rework the timer code to use a timer_map") Signed-off-by: Andrew Jones <[email protected]> [Simplified the patch to res we only care about emulated timers here] Signed-off-by: Marc Zyngier <[email protected]>
2019-06-12KVM: arm/arm64: vgic: Fix kvm_device leak in vgic_its_destroyDave Martin1-0/+1
kvm_device->destroy() seems to be supposed to free its kvm_device struct, but vgic_its_destroy() is not currently doing this, resulting in a memory leak, resulting in kmemleak reports such as the following: unreferenced object 0xffff800aeddfe280 (size 128): comm "qemu-system-aar", pid 13799, jiffies 4299827317 (age 1569.844s) [...] backtrace: [<00000000a08b80e2>] kmem_cache_alloc+0x178/0x208 [<00000000dcad2bd3>] kvm_vm_ioctl+0x350/0xbc0 Fix it. Cc: Andre Przywara <[email protected]> Fixes: 1085fdc68c60 ("KVM: arm64: vgic-its: Introduce new KVM ITS device") Signed-off-by: Dave Martin <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333Thomas Gleixner1-13/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Alexios Zavras <[email protected]> Reviewed-by: Allison Randal <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 320Thomas Gleixner1-13/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 33 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Alexios Zavras <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266Thomas Gleixner3-39/+3
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 67 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Richard Fontana <[email protected]> Reviewed-by: Alexios Zavras <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-06-05kvm: Convert kvm_lock to a mutexJunaid Shahid1-15/+15
It doesn't seem as if there is any particular need for kvm_lock to be a spinlock, so convert the lock to a mutex so that sleepable functions (in particular cond_resched()) can be called while holding it. Signed-off-by: Junaid Shahid <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-06-05KVM: irqchip: Use struct_size() in kzalloc()Gustavo A. R. Silva1-3/+1
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-06-04KVM: Directly return result from kvm_arch_check_processor_compat()Sean Christopherson2-5/+8
Add a wrapper to invoke kvm_arch_check_processor_compat() so that the boilerplate ugliness of checking virtualization support on all CPUs is hidden from the arch specific code. x86's implementation in particular is quite heinous, as it unnecessarily propagates the out-param pattern into kvm_x86_ops. While the x86 specific issue could be resolved solely by changing kvm_x86_ops, make the change for all architectures as returning a value directly is prettier and technically more robust, e.g. s390 doesn't set the out param, which could lead to subtle breakage in the (highly unlikely) scenario where the out-param was not pre-initialized by the caller. Opportunistically annotate svm_check_processor_compat() with __init. Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Cornelia Huck <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-06-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2-2/+5
Pull KVM fixes from Paolo Bonzini: "Fixes for PPC and s390" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: PPC: Book3S HV: Restore SPRG3 in kvmhv_p9_guest_entry() KVM: PPC: Book3S HV: Fix lockdep warning when entering guest on POWER9 KVM: PPC: Book3S HV: XIVE: Fix page offset when clearing ESB pages KVM: PPC: Book3S HV: XIVE: Take the srcu read lock when accessing memslots KVM: PPC: Book3S HV: XIVE: Do not clear IRQ data of passthrough interrupts KVM: PPC: Book3S HV: XIVE: Introduce a new mutex for the XIVE device KVM: PPC: Book3S HV: XIVE: Fix the enforced limit on the vCPU identifier KVM: PPC: Book3S HV: XIVE: Do not test the EQ flag validity when resetting KVM: PPC: Book3S HV: XIVE: Clear file mapping when device is released KVM: PPC: Book3S HV: Don't take kvm->lock around kvm_for_each_vcpu KVM: PPC: Book3S: Use new mutex to synchronize access to rtas token list KVM: PPC: Book3S HV: Use new mutex to synchronize MMU setup KVM: PPC: Book3S HV: Avoid touching arch.mmu_ready in XIVE release functions KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID kvm: fix compile on s390 part 2
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174Thomas Gleixner4-36/+4
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Richard Fontana <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-05-28KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_IDThomas Huth2-2/+3
KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all architectures. However, on s390x, the amount of usable CPUs is determined during runtime - it is depending on the features of the machine the code is running on. Since we are using the vcpu_id as an index into the SCA structures that are defined by the hardware (see e.g. the sca_add_vcpu() function), it is not only the amount of CPUs that is limited by the hard- ware, but also the range of IDs that we can use. Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too. So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common code into the architecture specific code, and on s390x we have to return the same value here as for KVM_CAP_MAX_VCPUS. This problem has been discovered with the kvm_create_max_vcpus selftest. With this change applied, the selftest now passes on s390x, too. Reviewed-by: Andrew Jones <[email protected]> Reviewed-by: Cornelia Huck <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Signed-off-by: Thomas Huth <[email protected]> Message-Id: <[email protected]> Cc: [email protected] Signed-off-by: Christian Borntraeger <[email protected]>
2019-05-28kvm: fix compile on s390 part 2Christian Borntraeger1-0/+2
We also need to fence the memunmap part. Fixes: e45adf665a53 ("KVM: Introduce a new guest mapping API") Fixes: d30b214d1d0a (kvm: fix compilation on s390) Cc: Michal Kubecek <[email protected]> Cc: KarimAllah Ahmed <[email protected]> Signed-off-by: Christian Borntraeger <[email protected]>
2019-05-26Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds4-122/+151
Pull KVM fixes from Paolo Bonzini: "The usual smattering of fixes and tunings that came in too late for the merge window, but should not wait four months before they appear in a release. I also travelled a bit more than usual in the first part of May, which didn't help with picking up patches and reports promptly" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (33 commits) KVM: x86: fix return value for reserved EFER tools/kvm_stat: fix fields filter for child events KVM: selftests: Wrap vcpu_nested_state_get/set functions with x86 guard kvm: selftests: aarch64: compile with warnings on kvm: selftests: aarch64: fix default vm mode kvm: selftests: aarch64: dirty_log_test: fix unaligned memslot size KVM: s390: fix memory slot handling for KVM_SET_USER_MEMORY_REGION KVM: x86/pmu: do not mask the value that is written to fixed PMUs KVM: x86/pmu: mask the result of rdpmc according to the width of the counters x86/kvm/pmu: Set AMD's virt PMU version to 1 KVM: x86: do not spam dmesg with VMCS/VMCB dumps kvm: Check irqchip mode before assign irqfd kvm: svm/avic: fix off-by-one in checking host APIC ID KVM: selftests: do not blindly clobber registers in guest asm KVM: selftests: Remove duplicated TEST_ASSERT in hyperv_cpuid.c KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace KVM: LAPIC: Fix lapic_timer_advance_ns parameter overflow kvm: vmx: Fix -Wmissing-prototypes warnings KVM: nVMX: Fix using __this_cpu_read() in preemptible context kvm: fix compilation on s390 ...
2019-05-24kvm: Check irqchip mode before assign irqfdPeter Xu1-0/+9
When assigning kvm irqfd we didn't check the irqchip mode but we allow KVM_IRQFD to succeed with all the irqchip modes. However it does not make much sense to create irqfd even without the kernel chips. Let's provide a arch-dependent helper to check whether a specific irqfd is allowed by the arch. At least for x86, it should make sense to check: - when irqchip mode is NONE, all irqfds should be disallowed, and, - when irqchip mode is SPLIT, irqfds that are with resamplefd should be disallowed. For either of the case, previously we'll silently ignore the irq or the irq ack event if the irqchip mode is incorrect. However that can cause misterious guest behaviors and it can be hard to triage. Let's fail KVM_IRQFD even earlier to detect these incorrect configurations. CC: Paolo Bonzini <[email protected]> CC: Radim Krčmář <[email protected]> CC: Alex Williamson <[email protected]> CC: Eduardo Habkost <[email protected]> Signed-off-by: Peter Xu <[email protected]> Cc: [email protected] Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-24kvm: fix compilation on s390Paolo Bonzini1-0/+2
s390 does not have memremap, even though in this particular case it would be useful. Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-24KVM: Fix spinlock taken warning during host resumeWanpeng Li1-1/+4
WARNING: CPU: 0 PID: 13554 at kvm/arch/x86/kvm//../../../virt/kvm/kvm_main.c:4183 kvm_resume+0x3c/0x40 [kvm] CPU: 0 PID: 13554 Comm: step_after_susp Tainted: G OE 5.1.0-rc4+ #1 RIP: 0010:kvm_resume+0x3c/0x40 [kvm] Call Trace: syscore_resume+0x63/0x2d0 suspend_devices_and_enter+0x9d1/0xa40 pm_suspend+0x33a/0x3b0 state_store+0x82/0xf0 kobj_attr_store+0x12/0x20 sysfs_kf_write+0x4b/0x60 kernfs_fop_write+0x120/0x1a0 __vfs_write+0x1b/0x40 vfs_write+0xcd/0x1d0 ksys_write+0x5f/0xe0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x6f/0x6c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Commit ca84d1a24 (KVM: x86: Add clock sync request to hardware enable) mentioned that "we always hold kvm_lock when hardware_enable is called. The one place that doesn't need to worry about it is resume, as resuming a frozen CPU, the spinlock won't be taken." However, commit 6706dae9 (virt/kvm: Replace spin_is_locked() with lockdep) introduces a bug, it asserts when the lock is not held which is contrary to the original goal. This patch fixes it by WARN_ON when the lock is held. Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Cc: Paul E. McKenney <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> Fixes: 6706dae9 ("virt/kvm: Replace spin_is_locked() with lockdep") [Wrap with #ifdef CONFIG_LOCKDEP - Paolo] Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-24KVM: arm/arm64: Move cc/it checks under hyp's Makefile to avoid instrumentationJames Morse2-121/+136
KVM has helpers to handle the condition codes of trapped aarch32 instructions. These are marked __hyp_text and used from HYP, but they aren't built by the 'hyp' Makefile, which has all the runes to avoid ASAN and KCOV instrumentation. Move this code to a new hyp/aarch32.c to avoid a hyp-panic when starting an aarch32 guest on a host built with the ASAN/KCOV debug options. Fixes: 021234ef3752f ("KVM: arm64: Make kvm_condition_valid32() accessible from EL2") Fixes: 8cebe750c4d9a ("arm64: KVM: Make kvm_skip_instr32 available to HYP") Signed-off-by: James Morse <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner3-0/+3
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-05-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds3-18/+131
Pull KVM updates from Paolo Bonzini: "ARM: - support for SVE and Pointer Authentication in guests - PMU improvements POWER: - support for direct access to the POWER9 XIVE interrupt controller - memory and performance optimizations x86: - support for accessing memory not backed by struct page - fixes and refactoring Generic: - dirty page tracking improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (155 commits) kvm: fix compilation on aarch64 Revert "KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU" kvm: x86: Fix L1TF mitigation for shadow MMU KVM: nVMX: Disable intercept for FS/GS base MSRs in vmcs02 when possible KVM: PPC: Book3S: Remove useless checks in 'release' method of KVM device KVM: PPC: Book3S HV: XIVE: Fix spelling mistake "acessing" -> "accessing" KVM: PPC: Book3S HV: Make sure to load LPID for radix VCPUs kvm: nVMX: Set nested_run_pending in vmx_set_nested_state after checks complete tests: kvm: Add tests for KVM_SET_NESTED_STATE KVM: nVMX: KVM_SET_NESTED_STATE - Tear down old EVMCS state before setting new state tests: kvm: Add tests for KVM_CAP_MAX_VCPUS and KVM_CAP_MAX_CPU_ID tests: kvm: Add tests to .gitignore KVM: Introduce KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 KVM: Fix kvm_clear_dirty_log_protect off-by-(minus-)one KVM: Fix the bitmap range to copy during clear dirty KVM: arm64: Fix ptrauth ID register masking logic KVM: x86: use direct accessors for RIP and RSP KVM: VMX: Use accessors for GPRs outside of dedicated caching logic KVM: x86: Omit caching logic for always-available GPRs kvm, x86: Properly check whether a pfn is an MMIO or not ...
2019-05-17kvm: fix compilation on aarch64Paolo Bonzini1-1/+1
Commit e45adf665a53 ("KVM: Introduce a new guest mapping API", 2019-01-31) introduced a build failure on aarch64 defconfig: $ make -j$(nproc) ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- O=out defconfig \ Image.gz ... ../arch/arm64/kvm/../../../virt/kvm/kvm_main.c: In function '__kvm_map_gfn': ../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1763:9: error: implicit declaration of function 'memremap'; did you mean 'memset_p'? ../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1763:46: error: 'MEMREMAP_WB' undeclared (first use in this function) ../arch/arm64/kvm/../../../virt/kvm/kvm_main.c: In function 'kvm_vcpu_unmap': ../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1795:3: error: implicit declaration of function 'memunmap'; did you mean 'vm_munmap'? because these functions are declared in <linux/io.h> rather than <asm/io.h>, and the former was being pulled in already on x86 but not on aarch64. Reported-by: Nathan Chancellor <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-15Merge tag 'kvmarm-for-v5.2' of ↵Paolo Bonzini1-6/+34
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for 5.2 - guest SVE support - guest Pointer Authentication support - Better discrimination of perf counters between host and guests Conflicts: include/uapi/linux/kvm.h
2019-05-15Merge tag 'kvm-ppc-next-5.2-2' of ↵Paolo Bonzini1-0/+18
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD PPC KVM update for 5.2 * Support for guests to access the new POWER9 XIVE interrupt controller hardware directly, reducing interrupt latency and overhead for guests. * In-kernel implementation of the H_PAGE_INIT hypercall. * Reduce memory usage of sparsely-populated IOMMU tables. * Several bug fixes. Second PPC KVM update for 5.2 * Fix a bug, fix a spelling mistake, remove some useless code.
2019-05-14mm/mmu_notifier: convert user range->blockable to helper functionJérôme Glisse1-1/+2
Use the mmu_notifier_range_blockable() helper function instead of directly dereferencing the range->blockable field. This is done to make it easier to change the mmu_notifier range field. This patch is the outcome of the following coccinelle patch: %<------------------------------------------------------------------- @@ identifier I1, FN; @@ FN(..., struct mmu_notifier_range *I1, ...) { <... -I1->blockable +mmu_notifier_range_blockable(I1) ...> } ------------------------------------------------------------------->% spatch --in-place --sp-file blockable.spatch --dir . Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Jérôme Glisse <[email protected]> Reviewed-by: Ralph Campbell <[email protected]> Reviewed-by: Ira Weiny <[email protected]> Cc: Christian König <[email protected]> Cc: Joonas Lahtinen <[email protected]> Cc: Jani Nikula <[email protected]> Cc: Rodrigo Vivi <[email protected]> Cc: Jan Kara <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Peter Xu <[email protected]> Cc: Felix Kuehling <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Ross Zwisler <[email protected]> Cc: Dan Williams <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Radim Krcmar <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Christian Koenig <[email protected]> Cc: John Hubbard <[email protected]> Cc: Arnd Bergmann <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-05-14KVM: PPC: Book3S: Remove useless checks in 'release' method of KVM deviceCédric Le Goater1-6/+0
There is no need to test for the device pointer validity when releasing a KVM device. The file descriptor should identify it safely. Fixes: 2bde9b3ec8bd ("KVM: Introduce a 'release' method for KVM devices") Signed-off-by: Cédric Le Goater <[email protected]> Reviewed-by: Alexey Kardashevskiy <[email protected]> Signed-off-by: Paul Mackerras <[email protected]>
2019-05-08KVM: Introduce KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2Peter Xu1-2/+2
The previous KVM_CAP_MANUAL_DIRTY_LOG_PROTECT has some problem which blocks the correct usage from userspace. Obsolete the old one and introduce a new capability bit for it. Suggested-by: Paolo Bonzini <[email protected]> Signed-off-by: Peter Xu <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-08KVM: Fix kvm_clear_dirty_log_protect off-by-(minus-)onePeter Xu1-2/+2
Just imaging the case where num_pages < BITS_PER_LONG, then the loop will be skipped while it shouldn't. Signed-off-by: Peter Xu <[email protected]> Fixes: 2a31b9db153530df4aa02dac8c32837bf5f47019 Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-08KVM: Fix the bitmap range to copy during clear dirtyPeter Xu1-1/+1
kvm_dirty_bitmap_bytes() will return the size of the dirty bitmap of the memslot rather than the size of bitmap passed over from the ioctl. Here for KVM_CLEAR_DIRTY_LOG we should only copy exactly the size of bitmap that covers kvm_clear_dirty_log.num_pages. Signed-off-by: Peter Xu <[email protected]> Cc: [email protected] Fixes: 2a31b9db153530df4aa02dac8c32837bf5f47019 Signed-off-by: Paolo Bonzini <[email protected]>
2019-05-06Merge tag 'arm64-upstream' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Mostly just incremental improvements here: - Introduce AT_HWCAP2 for advertising CPU features to userspace - Expose SVE2 availability to userspace - Support for "data cache clean to point of deep persistence" (DC PODP) - Honour "mitigations=off" on the cmdline and advertise status via sysfs - CPU timer erratum workaround (Neoverse-N1 #1188873) - Introduce perf PMU driver for the SMMUv3 performance counters - Add config option to disable the kuser helpers page for AArch32 tasks - Futex modifications to ensure liveness under contention - Rework debug exception handling to seperate kernel and user handlers - Non-critical fixes and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) Documentation: Add ARM64 to kernel-parameters.rst arm64/speculation: Support 'mitigations=' cmdline option arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB arm64: enable generic CPU vulnerabilites support arm64: add sysfs vulnerability show for speculative store bypass arm64: Fix size of __early_cpu_boot_status clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters clocksource/arm_arch_timer: Remove use of workaround static key clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable clocksource/arm_arch_timer: Direcly assign set_next_event workaround arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct ARM: vdso: Remove dependency with the arch_timer driver internals arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1 arm64: Add part number for Neoverse N1 arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32 arm64: mm: Remove pte_unmap_nested() arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable arm64: compat: Reduce address limit for 64K pages ...
2019-04-30KVM: Introduce a new guest mapping APIKarimAllah Ahmed1-0/+64
In KVM, specially for nested guests, there is a dominant pattern of: => map guest memory -> do_something -> unmap guest memory In addition to all this unnecessarily noise in the code due to boiler plate code, most of the time the mapping function does not properly handle memory that is not backed by "struct page". This new guest mapping API encapsulate most of this boiler plate code and also handles guest memory that is not backed by "struct page". The current implementation of this API is using memremap for memory that is not backed by a "struct page" which would lead to a huge slow-down if it was used for high-frequency mapping operations. The API does not have any effect on current setups where guest memory is backed by a "struct page". Further patches are going to also introduce a pfn-cache which would significantly improve the performance of the memremap case. Signed-off-by: KarimAllah Ahmed <[email protected]> Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>