Commit 1dda606c authored by Alexander Graf's avatar Alexander Graf Committed by Avi Kivity
Browse files

KVM: Add compat ioctl for KVM_SET_SIGNAL_MASK 



KVM has an ioctl to define which signal mask should be used while running
inside VCPU_RUN. At least for big endian systems, this mask is different
on 32-bit and 64-bit systems (though the size is identical).

Add a compat wrapper that converts the mask to whatever the kernel accepts,
allowing 32-bit kvm user space to set signal masks.

This patch fixes qemu with --enable-io-thread on ppc64 hosts when running
32-bit user land.

Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 91e3d71d

kernel/compat.c

+1 −0
Original line number Diff line number Diff line
@@ -890,6 +890,7 @@ sigset_from_compat (sigset_t *set, compat_sigset_t *compat) 
	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );

	}

}

EXPORT_SYMBOL_GPL(sigset_from_compat);



asmlinkage long

compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,

virt/kvm/kvm_main.c

+51 −1
Original line number Diff line number Diff line
@@ -84,6 +84,10 @@ struct dentry *kvm_debugfs_dir; 


static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,

			   unsigned long arg);

#ifdef CONFIG_COMPAT

static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,

				  unsigned long arg);

#endif

static int hardware_enable_all(void);

static void hardware_disable_all(void);
@@ -1586,7 +1590,9 @@ static int kvm_vcpu_release(struct inode *inode, struct file *filp) 
static struct file_operations kvm_vcpu_fops = {

	.release        = kvm_vcpu_release,

	.unlocked_ioctl = kvm_vcpu_ioctl,

	.compat_ioctl   = kvm_vcpu_ioctl,

#ifdef CONFIG_COMPAT

	.compat_ioctl   = kvm_vcpu_compat_ioctl,

#endif

	.mmap           = kvm_vcpu_mmap,

	.llseek		= noop_llseek,

};
@@ -1875,6 +1881,50 @@ out: 
	return r;

}



#ifdef CONFIG_COMPAT

static long kvm_vcpu_compat_ioctl(struct file *filp,

				  unsigned int ioctl, unsigned long arg)

{

	struct kvm_vcpu *vcpu = filp->private_data;

	void __user *argp = compat_ptr(arg);

	int r;



	if (vcpu->kvm->mm != current->mm)

		return -EIO;



	switch (ioctl) {

	case KVM_SET_SIGNAL_MASK: {

		struct kvm_signal_mask __user *sigmask_arg = argp;

		struct kvm_signal_mask kvm_sigmask;

		compat_sigset_t csigset;

		sigset_t sigset;



		if (argp) {

			r = -EFAULT;

			if (copy_from_user(&kvm_sigmask, argp,

					   sizeof kvm_sigmask))

				goto out;

			r = -EINVAL;

			if (kvm_sigmask.len != sizeof csigset)

				goto out;

			r = -EFAULT;

			if (copy_from_user(&csigset, sigmask_arg->sigset,

					   sizeof csigset))

				goto out;

		}

		sigset_from_compat(&sigset, &csigset);

		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);

		break;

	}

	default:

		r = kvm_vcpu_ioctl(filp, ioctl, arg);

	}



out:

	return r;

}

#endif



static long kvm_vm_ioctl(struct file *filp,

			   unsigned int ioctl, unsigned long arg)

{

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