diff options
author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2013-03-05 13:14:42 +0100 |
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committer | Marcelo Tosatti <mtosatti@redhat.com> | 2013-03-07 20:21:20 +0100 |
commit | 59a1fa2d80c0d351755cb29273b2b256dc4b3a11 (patch) | |
tree | 45c45e881ca3806a5d4c859519e471348c0d4a2d /arch/s390/kvm | |
parent | s390/mm,gmap: implement gmap_translate() (diff) | |
download | linux-59a1fa2d80c0d351755cb29273b2b256dc4b3a11.tar.xz linux-59a1fa2d80c0d351755cb29273b2b256dc4b3a11.zip |
s390/kvm,tprot: use new gmap_translate() function
When out-of-memory the tprot code incorrectly injected a program check
for the guest which reported an addressing exception even if the guest
address was valid.
Let's use the new gmap_translate() which translates a guest address to
a user space address whithout the chance of running into an out-of-memory
situation.
Also make it more explicit that for -EFAULT we won't find a vma.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch/s390/kvm')
-rw-r--r-- | arch/s390/kvm/priv.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 0ef9894606e5..75ad91e38e8a 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -575,20 +575,13 @@ static int handle_tprot(struct kvm_vcpu *vcpu) if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT) return -EOPNOTSUPP; - - /* we must resolve the address without holding the mmap semaphore. - * This is ok since the userspace hypervisor is not supposed to change - * the mapping while the guest queries the memory. Otherwise the guest - * might crash or get wrong info anyway. */ - user_address = (unsigned long) __guestaddr_to_user(vcpu, address1); - down_read(¤t->mm->mmap_sem); + user_address = __gmap_translate(address1, vcpu->arch.gmap); + if (IS_ERR_VALUE(user_address)) + goto out_inject; vma = find_vma(current->mm, user_address); - if (!vma) { - up_read(¤t->mm->mmap_sem); - return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - } - + if (!vma) + goto out_inject; vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44); if (!(vma->vm_flags & VM_WRITE) && (vma->vm_flags & VM_READ)) vcpu->arch.sie_block->gpsw.mask |= (1ul << 44); @@ -597,6 +590,10 @@ static int handle_tprot(struct kvm_vcpu *vcpu) up_read(¤t->mm->mmap_sem); return 0; + +out_inject: + up_read(¤t->mm->mmap_sem); + return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); } int kvm_s390_handle_e5(struct kvm_vcpu *vcpu) |