Marc Zyngier 92f35b751c KVM: arm/arm64: vgic: Allow more than 256 vcpus for KVM_IRQ_LINE ... While parts of the VGIC support a large number of vcpus (we bravely allow up to 512), other parts are more limited. One of these limits is visible in the KVM_IRQ_LINE ioctl, which only allows 256 vcpus to be signalled when using the CPU or PPI types. Unfortunately, we've cornered ourselves badly by allocating all the bits in the irq field. Since the irq_type subfield (8 bit wide) is currently only taking the values 0, 1 and 2 (and we have been careful not to allow anything else), let's reduce this field to only 4 bits, and allocate the remaining 4 bits to a vcpu2_index, which acts as a multiplier: vcpu_id = 256 * vcpu2_index + vcpu_index With that, and a new capability (KVM_CAP_ARM_IRQ_LINE_LAYOUT_2) allowing this to be discovered, it becomes possible to inject PPIs to up to 4096 vcpus. But please just don't. Whilst we're there, add a clarification about the use of KVM_IRQ_LINE on arm, which is not completely conditionned by KVM_CAP_IRQCHIP. Reported-by: Zenghui Yu <yuzenghui@huawei.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org>		2019-09-09 12:29:09 +01:00
..
auxvec.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
byteorder.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
fcntl.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
hwcap.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
ioctls.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
Kbuild	KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported	2019-03-28 17:27:42 +01:00
kvm.h	KVM: arm/arm64: vgic: Allow more than 256 vcpus for KVM_IRQ_LINE	2019-09-09 12:29:09 +01:00
mman.h
perf_regs.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
posix_types.h	License cleanup: add SPDX license identifier to uapi header files with a license	2017-11-02 11:20:11 +01:00
ptrace.h	ARM: SoC platform updates for 4.15	2017-11-16 14:05:12 -08:00
setup.h	docs: arm: convert docs to ReST and rename to *.rst	2019-07-15 09:20:24 -03:00
sigcontext.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
signal.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
stat.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
statfs.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
swab.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
types.h	License cleanup: add SPDX license identifier to uapi header files with no license	2017-11-02 11:19:54 +01:00
unistd.h	Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm	2017-11-16 12:50:35 -08:00