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Fri, 27 Feb 2026 08:57:16 +0000 (GMT) Date: Fri, 27 Feb 2026 09:57:14 +0100 From: Claudio Imbrenda To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, willy@infradead.org, david@kernel.org, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, gourry@gourry.net, ying.huang@linux.alibaba.com, apopple@nvidia.com, lorenzo.stoakes@oracle.com, baolin.wang@linux.alibaba.com, Liam.Howlett@oracle.com, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, vbabka@suse.cz, jannh@google.com, rppt@kernel.org, mhocko@suse.com, pfalcato@suse.de, kees@kernel.org, maddy@linux.ibm.com, npiggin@gmail.com, mpe@ellerman.id.au, chleroy@kernel.org, borntraeger@linux.ibm.com, frankja@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, svens@linux.ibm.com, gerald.schaefer@linux.ibm.com, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH v3 3/3] mm: use vma_start_write_killable() in process_vma_walk_lock() Message-ID: <20260227095714.5e69a0a8@p-imbrenda> In-Reply-To: References: <20260226070609.3072570-1-surenb@google.com> <20260226070609.3072570-4-surenb@google.com> <20260226191007.409a7a21@p-imbrenda> Organization: IBM X-Mailer: Claws Mail 4.3.1 (GTK 3.24.49; 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Ensure users handle EINTR correctly and do not ignore > > > it. > > > > > > Signed-off-by: Suren Baghdasaryan > > > --- > > > arch/s390/kvm/kvm-s390.c | 2 +- > > > fs/proc/task_mmu.c | 5 ++++- > > > mm/mempolicy.c | 14 +++++++++++--- > > > mm/pagewalk.c | 20 ++++++++++++++------ > > > mm/vma.c | 22 ++++++++++++++-------- > > > mm/vma.h | 6 ++++++ > > > 6 files changed, 50 insertions(+), 19 deletions(-) > > > > > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > > > index 7a175d86cef0..337e4f7db63a 100644 > > > --- a/arch/s390/kvm/kvm-s390.c > > > +++ b/arch/s390/kvm/kvm-s390.c > > > @@ -2948,7 +2948,7 @@ int kvm_arch_vm_ioctl(struct file *filp, unsign= ed int ioctl, unsigned long arg) > > > } > > > /* must be called without kvm->lock */ > > > r =3D kvm_s390_handle_pv(kvm, &args); > > > - if (copy_to_user(argp, &args, sizeof(args))) { > > > + if (r !=3D -EINTR && copy_to_user(argp, &args, sizeof(a= rgs))) { > > > r =3D -EFAULT; > > > break; > > > } =20 > > > > can you very briefly explain how we can end up with -EINTR here? > > > > do I understand correctly that -EINTR is possible here only if the > > process is being killed? =20 >=20 > Correct, it would happen if the process has a pending fatal signal > (like SIGKILL) in its signal queue. >=20 > > > > [...] =20 Acked-by: Claudio Imbrenda