From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D64A1385D9D for ; Tue, 12 May 2026 23:41:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778629284; cv=none; b=iKPKzg/2ZltXGAeNMBf/W4jOc9ZAIgeKtj+r4NhCFcFE8kGudkMrY82lUirZ8oUhyyiR3h7NNsukMidAcClVT3VPYjcwTdvGgJs3kEr99TFJGND4dX4IXIKa8ljpOXios2BpOqeRloHyRNSSwb2kK/I/f9ngcA+GLR5mV+hTvoA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778629284; c=relaxed/simple; bh=k6glw0fa1xZbNCk2CI4tGQalB7KYR7msKvRtehm/sOc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=HHsfAnJZdpBKpETiYo2egLbQkH+9ZT4OVjipbq1A2yjRzuVPy36MmpLKGTTs2H1HCEItdE7c0/axVLSlvs7Wnak4JYAAlv5NuyEgq/uDQj9dgt4ZKSxyKxD34WNh2wtJuP0ppC0I9f2dJyXSath3tQA49Cr6I8aK+NxZVGmn2cY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=eeqjakIH; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="eeqjakIH" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2b9b8137828so64686385ad.0 for ; Tue, 12 May 2026 16:41:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1778629281; x=1779234081; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Q4JJQhnqYlnKPfDWfphBogFKjvhlthhr+yORGRRz1NM=; b=eeqjakIHRSXldr3Pwxv2NfbIN17luRsYkUf3KAQCLkSBxYdPLZF5SEPAeZD4XQ8RSs K/4uF5q44nOdn+bYVFi03Iwl1CKuCHelH36Nf8yDHJs0x9ZMrZbdluA39HnvqHQNkXFh te1q/jXa09fsLU7rykCDmLMzXfmoAhTmp6Tv3DUFhG7I0vfIXs2FY2DTZYaruAkQkfaQ 4K9gAOdJm4st8gb/wEbb+RDERXpRgkBqCei1a0z0qOjoo6LbyhwFVJ8sQWvOajj0vni+ Wt/hywSPPMlLhB7DzRF+13EyOUmcp4o4LV5Z3iLo92C+hgbX470s8CYjhiGHJHle/8M1 hmqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778629281; x=1779234081; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Q4JJQhnqYlnKPfDWfphBogFKjvhlthhr+yORGRRz1NM=; b=mW3XUwlu8isg4TFj2CzDM6EfdXZK3jgutucd1Vf2p2wfaa18yGSJ0WVfAp3/+lr1WW d5e+N6JI/240E2CCHB0lkHJnOHGfPrZfh26i9z99Squ7V71rxenGFi/NgGkg3mFovWvE nLw4iFrcpEVp/2yrdj+kxhVEP/xFm+TdBuA9OQ+0PGknFRa3Cg+9Iq+E+mrtSw0FNMik dr/MswKO/fWRKNmKFWsbjN8zYe+68q9H07k+CrCf2CUtgzH8qL+N0I8mlKWMcu8NjRJw UvejoguPqVR8jrK55bV04IEZTCRqhQFIkTbRsn4CwAoElUv3SfQKWus3rltUfo08PRpb ybuw== X-Forwarded-Encrypted: i=1; AFNElJ8lzRJixLmalymlvLCf6xc94GmzFcGSwSqlFNM7CeJOCjHHWpO9v66keHAwPdFJ67NImACbQp4MUYPSFo04c+A=@vger.kernel.org X-Gm-Message-State: AOJu0Ywei0od+hxOSJGVp0OGRGTmeagPoMchr9iGVgPHpi9SGsf4nrlL bYv5Jt6wCsdUNbXU+pmqmWuTKIMex6lgswG9B3l9oaMp9SP6kGOwB5UGX9EBH9CHnlmmwAR9jqp UCTqcZw== X-Received: from plhv6.prod.google.com ([2002:a17:903:2386:b0:2ba:b55d:244c]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:d585:b0:2bc:ffe1:c380 with SMTP id d9443c01a7336-2bd2f4dbbbcmr3504675ad.8.1778629280961; Tue, 12 May 2026 16:41:20 -0700 (PDT) Date: Tue, 12 May 2026 16:41:20 -0700 In-Reply-To: <20260508015013.4108345-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260508015013.4108345-1-maobibo@loongson.cn> Message-ID: Subject: Re: [PATCH] KVM: selftests: Check guest memfd validity with flags From: Sean Christopherson To: Bibo Mao Cc: Paolo Bonzini , Oliver Upton , Marc Zyngier , kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Fri, May 08, 2026, Bibo Mao wrote: > The type of guest_memfd in structure kvm_userspace_memory_region2 > is __u32, it is not correct to assign it with -1 and check whether > it is smaller than 0. Here check flags with KVM_MEM_GUEST_MEMFD > set. > > Signed-off-by: Bibo Mao > --- > tools/testing/selftests/kvm/lib/kvm_util.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c > index 2a76eca7029d..9d3553f7e6a5 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -817,7 +817,7 @@ static void __vm_mem_region_delete(struct kvm_vm *vm, > kvm_munmap(region->mmap_alias, region->mmap_size); > close(region->fd); > } > - if (region->region.guest_memfd >= 0) > + if (region->region.flags & KVM_MEM_GUEST_MEMFD) Hmm, it's a bit gross, but this is probably more robust? if ((int)region->region.guest_memfd < 0) E.g. if we somehow end up in a state where KVM_MEM_GUEST_MEMFD is either stale or the guest_memfd file was already closed. I highly doubt either of those things will happen, but logically it's the correct fix (the only reason guest_memfd is a u32 is being it's part of the kernel's uAPI).