On Mon, Mar 23, 2026 at 10:53 AM Lorenzo Stoakes (Oracle) <[email protected]> wrote: > > On Sat, Mar 21, 2026 at 10:43:07PM -0700, Suren Baghdasaryan wrote: > > If kvm_s390_handle_pv() call fails its error code gets recorded but > > execution proceeds as if the call was successful. If the next call to > > copy_to_user() fails then the original error is overwritten. > > Is that really a big deal though, as you're returning an error in either case? > > > The follow-up patch adds fatal signal checks during VMA walk, which > > makes it possible for kvm_s390_handle_pv() to return EINTR error. > > Without this fix any error including EINTR can be overwritten and > > original error will be lost. > > > > Change error handling for kvm_s390_handle_pv() to alter normal flow > > once failure happens. This is consistent with how kvm_arch_vm_ioctl > > handles errors for other ioctl commands. > > > > Signed-off-by: Suren Baghdasaryan <[email protected]> > > --- > > arch/s390/kvm/kvm-s390.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > > index 3eb60aa932ec..ddad08c0926f 100644 > > --- a/arch/s390/kvm/kvm-s390.c > > +++ b/arch/s390/kvm/kvm-s390.c > > @@ -2947,6 +2947,8 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int > > ioctl, unsigned long arg) > > } > > /* must be called without kvm->lock */ > > r = kvm_s390_handle_pv(kvm, &args); > > + if (r) > > + break; > > if (copy_to_user(argp, &args, sizeof(args))) { > > Yeah as per Sashiko we probably need to copy_to_user() still. > > But in that case, do we even need a change at all? I'm not sure it really > matters which error code terminates things does it?
I agree. I plan to drop this patch from the series (see my former reply) unless someone tells me otherwise. > > > r = -EFAULT; > > break; > > -- > > 2.53.0.1018.g2bb0e51243-goog > > > > Thanks, Lorenzo
