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AJvYcCXEG0c0f5Crx+WeWnCdem8XOYf044/NjvfmsXNuT1QdY/N2EH6JAYLwS/AvQl2T3rSzQ7yYpg==@lists.linux.dev X-Gm-Message-State: AOJu0YwgHjrUdcSc+w/vOKlLUvc/2DHk81gg8Q5rFhKA/pDIo7hijne6 1q2nNVXbdcLvzTvJK9y6OJu79gyp5KZvMPeKAAICjajt2CPDTYHEh7XdKuYAc2yK4uDn2m0YSq0 nBA== X-Received: from dlbtp9.prod.google.com ([2002:a05:7022:3b89:b0:128:ee08:8c14]) (user=wnliu job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:ec17:b0:12b:ebb8:e421 with SMTP id a92af1059eb24-12bfb777fc2mr7760400c88.35.1775545308935; Tue, 07 Apr 2026 00:01:48 -0700 (PDT) Date: Tue, 7 Apr 2026 07:01:46 +0000 In-Reply-To: <20260330084206.9251-6-suravee.suthikulpanit@amd.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260330084206.9251-6-suravee.suthikulpanit@amd.com> X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260407070147.623349-1-wnliu@google.com> Subject: Re: [PATCH 05/22] iommu/amd: Introduce vIOMMU Guest-ID (GID) From: Weinan Liu To: suravee.suthikulpanit@amd.com Cc: chriscli@google.com, dantuluris@google.com, iommu@lists.linux.dev, jay.chen@amd.com, jgg@nvidia.com, jon.grimm@amd.com, joro@8bytes.org, kevin.tian@intel.com, kpsingh@google.com, linux-kernel@vger.kernel.org, nicolinc@nvidia.com, sairaj.arunkodilkar@amd.com, santosh.shukla@amd.com, vasant.hegde@amd.com, wnliu@google.com, wvw@google.com, yi.l.liu@intel.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, Mar 30, 2026 at 1:43=E2=80=AFAM Suravee Suthikulpanit wrote: > diff --git a/drivers/iommu/amd/iommufd.c b/drivers/iommu/amd/iommufd.c > index e7ffa7e8915b..6fba5d9b1310 100644 > --- a/drivers/iommu/amd/iommufd.c > +++ b/drivers/iommu/amd/iommufd.c > @@ -43,13 +43,35 @@ size_t amd_iommufd_get_viommu_size(struct device *dev= , enum iommu_viommu_type vi > =C2=A0int amd_iommufd_viommu_init(struct iommufd_viommu *viommu, struct i= ommu_domain *parent, > =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 const struct iommu_user_data *user_data) > =C2=A0{ > + =C2=A0 =C2=A0 =C2=A0 aviommu->gid =3D amd_iommu_gid_alloc(); Since the gid is defined as a u16, the return value from amd_iommu_gid_allo= c() will cast any negative error codes to a large positive value. > + =C2=A0 =C2=A0 =C2=A0 if (aviommu->gid < 0) > + =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 return aviommu->gid;