* [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width @ 2021-04-07 18:40 Saeed Mirzamohammadi 2021-04-08 0:25 ` Lu Baolu 0 siblings, 1 reply; 6+ messages in thread From: Saeed Mirzamohammadi @ 2021-04-07 18:40 UTC (permalink / raw) Cc: saeed.mirzamohammadi, Camille Lu, linux-kernel, iommu, David Woodhouse The IOMMU driver calculates the guest addressability for a DMA request based on the value of the mgaw reported from the IOMMU. However, this is a fused value and as mentioned in the spec, the guest width should be calculated based on the minimum of supported adjusted guest address width (SAGAW) and MGAW. This is from specification: "Guest addressability for a given DMA request is limited to the minimum of the value reported through this field and the adjusted guest address width of the corresponding page-table structure. (Adjusted guest address widths supported by hardware are reported through the SAGAW field)." This causes domain initialization to fail and following errors appear for EHCI PCI driver: [ 2.486393] ehci-pci 0000:01:00.4: EHCI Host Controller [ 2.486624] ehci-pci 0000:01:00.4: new USB bus registered, assigned bus number 1 [ 2.489127] ehci-pci 0000:01:00.4: DMAR: Allocating domain failed [ 2.489350] ehci-pci 0000:01:00.4: DMAR: 32bit DMA uses non-identity mapping [ 2.489359] ehci-pci 0000:01:00.4: can't setup: -12 [ 2.489531] ehci-pci 0000:01:00.4: USB bus 1 deregistered [ 2.490023] ehci-pci 0000:01:00.4: init 0000:01:00.4 fail, -12 [ 2.490358] ehci-pci: probe of 0000:01:00.4 failed with error -12 This issue happens when the value of the sagaw corresponds to a 48-bit agaw. This fix updates the calculation of the agaw based on the minimum of IOMMU's sagaw value and MGAW. Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com> Tested-by: Camille Lu <camille.lu@hpe.com> --- Change in v2: - Added cap_width to calculate AGAW based on the minimum value of MGAW and AGAW. --- drivers/iommu/intel-iommu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 953d86ca6d2b..a2a03df97704 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1853,7 +1853,7 @@ static inline int guestwidth_to_adjustwidth(int gaw) static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, int guest_width) { - int adjust_width, agaw; + int adjust_width, agaw, cap_width; unsigned long sagaw; int err; @@ -1867,8 +1867,9 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, domain_reserve_special_ranges(domain); /* calculate AGAW */ - if (guest_width > cap_mgaw(iommu->cap)) - guest_width = cap_mgaw(iommu->cap); + cap_width = min_t(int, cap_mgaw(iommu->cap), agaw_to_width(iommu->agaw)); + if (guest_width > cap_width) + guest_width = cap_width; domain->gaw = guest_width; adjust_width = guestwidth_to_adjustwidth(guest_width); agaw = width_to_agaw(adjust_width); -- 2.27.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width 2021-04-07 18:40 [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width Saeed Mirzamohammadi @ 2021-04-08 0:25 ` Lu Baolu 2021-04-11 19:36 ` Saeed Mirzamohammadi 0 siblings, 1 reply; 6+ messages in thread From: Lu Baolu @ 2021-04-08 0:25 UTC (permalink / raw) To: Saeed Mirzamohammadi; +Cc: Camille Lu, linux-kernel, iommu, David Woodhouse On 4/8/21 2:40 AM, Saeed Mirzamohammadi wrote: > The IOMMU driver calculates the guest addressability for a DMA request > based on the value of the mgaw reported from the IOMMU. However, this > is a fused value and as mentioned in the spec, the guest width > should be calculated based on the minimum of supported adjusted guest > address width (SAGAW) and MGAW. > > This is from specification: > "Guest addressability for a given DMA request is limited to the > minimum of the value reported through this field and the adjusted > guest address width of the corresponding page-table structure. > (Adjusted guest address widths supported by hardware are reported > through the SAGAW field)." > > This causes domain initialization to fail and following > errors appear for EHCI PCI driver: > > [ 2.486393] ehci-pci 0000:01:00.4: EHCI Host Controller > [ 2.486624] ehci-pci 0000:01:00.4: new USB bus registered, assigned bus > number 1 > [ 2.489127] ehci-pci 0000:01:00.4: DMAR: Allocating domain failed > [ 2.489350] ehci-pci 0000:01:00.4: DMAR: 32bit DMA uses non-identity > mapping > [ 2.489359] ehci-pci 0000:01:00.4: can't setup: -12 > [ 2.489531] ehci-pci 0000:01:00.4: USB bus 1 deregistered > [ 2.490023] ehci-pci 0000:01:00.4: init 0000:01:00.4 fail, -12 > [ 2.490358] ehci-pci: probe of 0000:01:00.4 failed with error -12 > > This issue happens when the value of the sagaw corresponds to a > 48-bit agaw. This fix updates the calculation of the agaw based on > the minimum of IOMMU's sagaw value and MGAW. > > Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com> > Tested-by: Camille Lu <camille.lu@hpe.com> > --- > > Change in v2: > - Added cap_width to calculate AGAW based on the minimum value of MGAW and AGAW. > --- > drivers/iommu/intel-iommu.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index 953d86ca6d2b..a2a03df97704 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -1853,7 +1853,7 @@ static inline int guestwidth_to_adjustwidth(int gaw) > static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, > int guest_width) > { > - int adjust_width, agaw; > + int adjust_width, agaw, cap_width; > unsigned long sagaw; > int err; > > @@ -1867,8 +1867,9 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, > domain_reserve_special_ranges(domain); > > /* calculate AGAW */ > - if (guest_width > cap_mgaw(iommu->cap)) > - guest_width = cap_mgaw(iommu->cap); > + cap_width = min_t(int, cap_mgaw(iommu->cap), agaw_to_width(iommu->agaw)); > + if (guest_width > cap_width) > + guest_width = cap_width; > domain->gaw = guest_width; > adjust_width = guestwidth_to_adjustwidth(guest_width); > agaw = width_to_agaw(adjust_width); > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width 2021-04-08 0:25 ` Lu Baolu @ 2021-04-11 19:36 ` Saeed Mirzamohammadi 2021-04-11 23:49 ` Lu Baolu 0 siblings, 1 reply; 6+ messages in thread From: Saeed Mirzamohammadi @ 2021-04-11 19:36 UTC (permalink / raw) To: Lu Baolu; +Cc: David Woodhouse, Camille Lu, iommu, linux-kernel [-- Attachment #1.1: Type: text/plain, Size: 3200 bytes --] Hi Lu, Thanks for the review. May I know when do we expect this to be applied to 5.4? Thanks, Saeed On Apr 7, 2021, at 5:25 PM, Lu Baolu <baolu.lu@linux.intel.com<mailto:baolu.lu@linux.intel.com>> wrote: On 4/8/21 2:40 AM, Saeed Mirzamohammadi wrote: The IOMMU driver calculates the guest addressability for a DMA request based on the value of the mgaw reported from the IOMMU. However, this is a fused value and as mentioned in the spec, the guest width should be calculated based on the minimum of supported adjusted guest address width (SAGAW) and MGAW. This is from specification: "Guest addressability for a given DMA request is limited to the minimum of the value reported through this field and the adjusted guest address width of the corresponding page-table structure. (Adjusted guest address widths supported by hardware are reported through the SAGAW field)." This causes domain initialization to fail and following errors appear for EHCI PCI driver: [ 2.486393] ehci-pci 0000:01:00.4: EHCI Host Controller [ 2.486624] ehci-pci 0000:01:00.4: new USB bus registered, assigned bus number 1 [ 2.489127] ehci-pci 0000:01:00.4: DMAR: Allocating domain failed [ 2.489350] ehci-pci 0000:01:00.4: DMAR: 32bit DMA uses non-identity mapping [ 2.489359] ehci-pci 0000:01:00.4: can't setup: -12 [ 2.489531] ehci-pci 0000:01:00.4: USB bus 1 deregistered [ 2.490023] ehci-pci 0000:01:00.4: init 0000:01:00.4 fail, -12 [ 2.490358] ehci-pci: probe of 0000:01:00.4 failed with error -12 This issue happens when the value of the sagaw corresponds to a 48-bit agaw. This fix updates the calculation of the agaw based on the minimum of IOMMU's sagaw value and MGAW. Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com<mailto:saeed.mirzamohammadi@oracle.com>> Tested-by: Camille Lu <camille.lu@hpe.com<mailto:camille.lu@hpe.com>> --- Change in v2: - Added cap_width to calculate AGAW based on the minimum value of MGAW and AGAW. --- drivers/iommu/intel-iommu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 953d86ca6d2b..a2a03df97704 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1853,7 +1853,7 @@ static inline int guestwidth_to_adjustwidth(int gaw) static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, int guest_width) { - int adjust_width, agaw; + int adjust_width, agaw, cap_width; unsigned long sagaw; int err; @@ -1867,8 +1867,9 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, domain_reserve_special_ranges(domain); /* calculate AGAW */ - if (guest_width > cap_mgaw(iommu->cap)) - guest_width = cap_mgaw(iommu->cap); + cap_width = min_t(int, cap_mgaw(iommu->cap), agaw_to_width(iommu->agaw)); + if (guest_width > cap_width) + guest_width = cap_width; domain->gaw = guest_width; adjust_width = guestwidth_to_adjustwidth(guest_width); agaw = width_to_agaw(adjust_width); Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com<mailto:baolu.lu@linux.intel.com>> Best regards, baolu [-- Attachment #1.2: Type: text/html, Size: 10374 bytes --] [-- Attachment #2: Type: text/plain, Size: 156 bytes --] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width 2021-04-11 19:36 ` Saeed Mirzamohammadi @ 2021-04-11 23:49 ` Lu Baolu 2021-04-12 18:25 ` Saeed Mirzamohammadi 0 siblings, 1 reply; 6+ messages in thread From: Lu Baolu @ 2021-04-11 23:49 UTC (permalink / raw) To: Saeed Mirzamohammadi; +Cc: Camille Lu, linux-kernel, iommu, David Woodhouse I guess you need to ask Greg KH <gregkh@linuxfoundation.org> with this Cc-ing to stable@vger.kernel.org. Best regards, baolu On 2021/4/12 3:36, Saeed Mirzamohammadi wrote: > Hi Lu, > > Thanks for the review. May I know when do we expect this to be applied > to 5.4? > > Thanks, > Saeed > >> On Apr 7, 2021, at 5:25 PM, Lu Baolu <baolu.lu@linux.intel.com >> <mailto:baolu.lu@linux.intel.com>> wrote: >> >> On 4/8/21 2:40 AM, Saeed Mirzamohammadi wrote: >>> The IOMMU driver calculates the guest addressability for a DMA request >>> based on the value of the mgaw reported from the IOMMU. However, this >>> is a fused value and as mentioned in the spec, the guest width >>> should be calculated based on the minimum of supported adjusted guest >>> address width (SAGAW) and MGAW. >>> This is from specification: >>> "Guest addressability for a given DMA request is limited to the >>> minimum of the value reported through this field and the adjusted >>> guest address width of the corresponding page-table structure. >>> (Adjusted guest address widths supported by hardware are reported >>> through the SAGAW field)." >>> This causes domain initialization to fail and following >>> errors appear for EHCI PCI driver: >>> [ 2.486393] ehci-pci 0000:01:00.4: EHCI Host Controller >>> [ 2.486624] ehci-pci 0000:01:00.4: new USB bus registered, >>> assigned bus >>> number 1 >>> [ 2.489127] ehci-pci 0000:01:00.4: DMAR: Allocating domain failed >>> [ 2.489350] ehci-pci 0000:01:00.4: DMAR: 32bit DMA uses non-identity >>> mapping >>> [ 2.489359] ehci-pci 0000:01:00.4: can't setup: -12 >>> [ 2.489531] ehci-pci 0000:01:00.4: USB bus 1 deregistered >>> [ 2.490023] ehci-pci 0000:01:00.4: init 0000:01:00.4 fail, -12 >>> [ 2.490358] ehci-pci: probe of 0000:01:00.4 failed with error -12 >>> This issue happens when the value of the sagaw corresponds to a >>> 48-bit agaw. This fix updates the calculation of the agaw based on >>> the minimum of IOMMU's sagaw value and MGAW. >>> Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com >>> <mailto:saeed.mirzamohammadi@oracle.com>> >>> Tested-by: Camille Lu <camille.lu@hpe.com <mailto:camille.lu@hpe.com>> >>> --- >>> Change in v2: >>> - Added cap_width to calculate AGAW based on the minimum value of >>> MGAW and AGAW. >>> --- >>> drivers/iommu/intel-iommu.c | 7 ++++--- >>> 1 file changed, 4 insertions(+), 3 deletions(-) >>> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c >>> index 953d86ca6d2b..a2a03df97704 100644 >>> --- a/drivers/iommu/intel-iommu.c >>> +++ b/drivers/iommu/intel-iommu.c >>> @@ -1853,7 +1853,7 @@ static inline int guestwidth_to_adjustwidth(int >>> gaw) >>> static int domain_init(struct dmar_domain *domain, struct >>> intel_iommu *iommu, >>> int guest_width) >>> { >>> -int adjust_width, agaw; >>> +int adjust_width, agaw, cap_width; >>> unsigned long sagaw; >>> int err; >>> @@ -1867,8 +1867,9 @@ static int domain_init(struct dmar_domain >>> *domain, struct intel_iommu *iommu, >>> domain_reserve_special_ranges(domain); >>> /* calculate AGAW */ >>> -if (guest_width > cap_mgaw(iommu->cap)) >>> -guest_width = cap_mgaw(iommu->cap); >>> +cap_width = min_t(int, cap_mgaw(iommu->cap), >>> agaw_to_width(iommu->agaw)); >>> +if (guest_width > cap_width) >>> +guest_width = cap_width; >>> domain->gaw = guest_width; >>> adjust_width = guestwidth_to_adjustwidth(guest_width); >>> agaw = width_to_agaw(adjust_width); >> >> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com >> <mailto:baolu.lu@linux.intel.com>> >> >> Best regards, >> baolu > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width 2021-04-11 23:49 ` Lu Baolu @ 2021-04-12 18:25 ` Saeed Mirzamohammadi 2021-04-12 18:45 ` gregkh 0 siblings, 1 reply; 6+ messages in thread From: Saeed Mirzamohammadi @ 2021-04-12 18:25 UTC (permalink / raw) To: gregkh; +Cc: Camille Lu, linux-kernel, stable, iommu, David Woodhouse Hi Greg, This patch fixes an issue with the IOMMU driver and it only applies to 5.4, 4.19, and 4.14 stable kernels. May I know when this patch would be available in the stable kernels? Subject: iommu/vt-d: Fix agaw for a supported 48 bit guest address width Thanks, Saeed > On Apr 11, 2021, at 4:49 PM, Lu Baolu <baolu.lu@linux.intel.com> wrote: > > I guess you need to ask Greg KH <gregkh@linuxfoundation.org> with this > Cc-ing to stable@vger.kernel.org. > > Best regards, > baolu > > On 2021/4/12 3:36, Saeed Mirzamohammadi wrote: >> Hi Lu, >> Thanks for the review. May I know when do we expect this to be applied to 5.4? >> Thanks, >> Saeed >>> On Apr 7, 2021, at 5:25 PM, Lu Baolu <baolu.lu@linux.intel.com <mailto:baolu.lu@linux.intel.com>> wrote: >>> >>> On 4/8/21 2:40 AM, Saeed Mirzamohammadi wrote: >>>> The IOMMU driver calculates the guest addressability for a DMA request >>>> based on the value of the mgaw reported from the IOMMU. However, this >>>> is a fused value and as mentioned in the spec, the guest width >>>> should be calculated based on the minimum of supported adjusted guest >>>> address width (SAGAW) and MGAW. >>>> This is from specification: >>>> "Guest addressability for a given DMA request is limited to the >>>> minimum of the value reported through this field and the adjusted >>>> guest address width of the corresponding page-table structure. >>>> (Adjusted guest address widths supported by hardware are reported >>>> through the SAGAW field)." >>>> This causes domain initialization to fail and following >>>> errors appear for EHCI PCI driver: >>>> [ 2.486393] ehci-pci 0000:01:00.4: EHCI Host Controller >>>> [ 2.486624] ehci-pci 0000:01:00.4: new USB bus registered, assigned bus >>>> number 1 >>>> [ 2.489127] ehci-pci 0000:01:00.4: DMAR: Allocating domain failed >>>> [ 2.489350] ehci-pci 0000:01:00.4: DMAR: 32bit DMA uses non-identity >>>> mapping >>>> [ 2.489359] ehci-pci 0000:01:00.4: can't setup: -12 >>>> [ 2.489531] ehci-pci 0000:01:00.4: USB bus 1 deregistered >>>> [ 2.490023] ehci-pci 0000:01:00.4: init 0000:01:00.4 fail, -12 >>>> [ 2.490358] ehci-pci: probe of 0000:01:00.4 failed with error -12 >>>> This issue happens when the value of the sagaw corresponds to a >>>> 48-bit agaw. This fix updates the calculation of the agaw based on >>>> the minimum of IOMMU's sagaw value and MGAW. >>>> Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com <mailto:saeed.mirzamohammadi@oracle.com>> >>>> Tested-by: Camille Lu <camille.lu@hpe.com <mailto:camille.lu@hpe.com>> >>>> --- >>>> Change in v2: >>>> - Added cap_width to calculate AGAW based on the minimum value of MGAW and AGAW. >>>> --- >>>> drivers/iommu/intel-iommu.c | 7 ++++--- >>>> 1 file changed, 4 insertions(+), 3 deletions(-) >>>> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c >>>> index 953d86ca6d2b..a2a03df97704 100644 >>>> --- a/drivers/iommu/intel-iommu.c >>>> +++ b/drivers/iommu/intel-iommu.c >>>> @@ -1853,7 +1853,7 @@ static inline int guestwidth_to_adjustwidth(int gaw) >>>> static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, >>>> int guest_width) >>>> { >>>> -int adjust_width, agaw; >>>> +int adjust_width, agaw, cap_width; >>>> unsigned long sagaw; >>>> int err; >>>> @@ -1867,8 +1867,9 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, >>>> domain_reserve_special_ranges(domain); >>>> /* calculate AGAW */ >>>> -if (guest_width > cap_mgaw(iommu->cap)) >>>> -guest_width = cap_mgaw(iommu->cap); >>>> +cap_width = min_t(int, cap_mgaw(iommu->cap), agaw_to_width(iommu->agaw)); >>>> +if (guest_width > cap_width) >>>> +guest_width = cap_width; >>>> domain->gaw = guest_width; >>>> adjust_width = guestwidth_to_adjustwidth(guest_width); >>>> agaw = width_to_agaw(adjust_width); >>> >>> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com <mailto:baolu.lu@linux.intel.com>> >>> >>> Best regards, >>> baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width 2021-04-12 18:25 ` Saeed Mirzamohammadi @ 2021-04-12 18:45 ` gregkh 0 siblings, 0 replies; 6+ messages in thread From: gregkh @ 2021-04-12 18:45 UTC (permalink / raw) To: Saeed Mirzamohammadi Cc: Camille Lu, linux-kernel, stable, iommu, David Woodhouse On Mon, Apr 12, 2021 at 06:25:44PM +0000, Saeed Mirzamohammadi wrote: > Hi Greg, > > This patch fixes an issue with the IOMMU driver and it only applies to 5.4, 4.19, and 4.14 stable kernels. May I know when this patch would be available in the stable kernels? > > Subject: iommu/vt-d: Fix agaw for a supported 48 bit guest address width > <formletter> This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly. </formletter> _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-04-12 18:45 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-04-07 18:40 [PATCH 5.4 v2 1/1] iommu/vt-d: Fix agaw for a supported 48 bit guest address width Saeed Mirzamohammadi 2021-04-08 0:25 ` Lu Baolu 2021-04-11 19:36 ` Saeed Mirzamohammadi 2021-04-11 23:49 ` Lu Baolu 2021-04-12 18:25 ` Saeed Mirzamohammadi 2021-04-12 18:45 ` gregkh
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