* [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies @ 2017-04-13 8:55 Nate Watterson 2017-04-13 11:21 ` Robin Murphy 0 siblings, 1 reply; 8+ messages in thread From: Nate Watterson @ 2017-04-13 8:55 UTC (permalink / raw) To: robin.murphy, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd, Nate Watterson Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} making them unsuitable for use with iommu_domains having an IOMMU_DMA_MSI cookie since the cookie's iova_domain member, iovad, is uninitialized. Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless of cookie type, failures are being seen when mapping MSI target addresses for devices attached to UNMANAGED domains. To work around this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is initialized to the value returned by cookie_msi_granule(). Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") Signed-off-by: Nate Watterson <nwatters@codeaurora.org> --- drivers/iommu/dma-iommu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 8348f366..d7b0816 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) cookie->msi_iova = base; domain->iova_cookie = cookie; + + /* + * Setup granule for compatibility with __iommu_dma_{alloc/free} and + * add a compile time check to ensure that writing granule won't + * clobber msi_iova. + */ + cookie->iovad.granule = cookie_msi_granule(cookie); + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < + sizeof(cookie->msi_iova)); + return 0; } EXPORT_SYMBOL(iommu_get_msi_cookie); -- Qualcomm Datacenter Technologies, Inc. on behalf of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-04-13 8:55 [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies Nate Watterson @ 2017-04-13 11:21 ` Robin Murphy 2017-04-13 14:29 ` Shanker Donthineni 2017-04-13 19:38 ` Nate Watterson 0 siblings, 2 replies; 8+ messages in thread From: Robin Murphy @ 2017-04-13 11:21 UTC (permalink / raw) To: Nate Watterson, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd Hi Nate, On 13/04/17 09:55, Nate Watterson wrote: > Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} > making them unsuitable for use with iommu_domains having an IOMMU_DMA_MSI > cookie since the cookie's iova_domain member, iovad, is uninitialized. > > Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless > of cookie type, failures are being seen when mapping MSI target > addresses for devices attached to UNMANAGED domains. To work around > this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is > initialized to the value returned by cookie_msi_granule(). Oh bum. Thanks for the report. However, I really don't like bodging around it with deliberate undefined behaviour. Fixing things properly doesn't seem too hard: ----->8----- diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 8348f366ddd1..62618e77bedc 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie, dma_addr_t iova, size_t size) { struct iova_domain *iovad = &cookie->iovad; - unsigned long shift = iova_shift(iovad); /* The MSI case is only ever cleaning up its most recent allocation */ if (cookie->type == IOMMU_DMA_MSI_COOKIE) cookie->msi_iova -= size; else - free_iova_fast(iovad, iova >> shift, size >> shift); + free_iova_fast(iovad, iova_pfn(iovad, iova), + size >> iova_shift(iovad)); } static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t dma_addr, @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; - struct iova_domain *iovad = &cookie->iovad; - size_t iova_off = iova_offset(iovad, phys); + size_t iova_off = 0; dma_addr_t iova; - size = iova_align(iovad, size + iova_off); + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { + iova_off = iova_offset(&cookie->iovad, phys); + size = iova_align(&cookie->iovad, size + iova_off); + } + iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev); if (!iova) return DMA_ERROR_CODE; -----8<----- Untested, and you'll probably want to double-check it anyway given that the original oversight was mine in the first place ;) Robin. > Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") > Signed-off-by: Nate Watterson <nwatters@codeaurora.org> > --- > drivers/iommu/dma-iommu.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 8348f366..d7b0816 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) > > cookie->msi_iova = base; > domain->iova_cookie = cookie; > + > + /* > + * Setup granule for compatibility with __iommu_dma_{alloc/free} and > + * add a compile time check to ensure that writing granule won't > + * clobber msi_iova. > + */ > + cookie->iovad.granule = cookie_msi_granule(cookie); > + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < > + sizeof(cookie->msi_iova)); > + > return 0; > } > EXPORT_SYMBOL(iommu_get_msi_cookie); > ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-04-13 11:21 ` Robin Murphy @ 2017-04-13 14:29 ` Shanker Donthineni 2017-05-04 13:32 ` Bharat Bhushan 2017-04-13 19:38 ` Nate Watterson 1 sibling, 1 reply; 8+ messages in thread From: Shanker Donthineni @ 2017-04-13 14:29 UTC (permalink / raw) To: Robin Murphy, Nate Watterson, Joerg Roedel, iommu, linux-kernel Hi Robin, I tested your changes and the device pass-through feature works fine on QDF2400 server platform. Maybe Nate comments on the patch contents but it fixes the problem. @@ -317,13 +317,13 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie, dma_addr_t iova, size_t size) { struct iova_domain *iovad = &cookie->iovad; - unsigned long shift = iova_shift(iovad); /* The MSI case is only ever cleaning up its most recent allocation */ if (cookie->type == IOMMU_DMA_MSI_COOKIE) cookie->msi_iova -= size; else - free_iova_fast(iovad, iova >> shift, size >> shift); + free_iova_fast(iovad, iova_pfn(iovad, iova), + size >> iova_shift(iovad)); } static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t dma_addr, @@ -538,11 +538,14 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; - struct iova_domain *iovad = &cookie->iovad; - size_t iova_off = iova_offset(iovad, phys); + size_t iova_off = 0; dma_addr_t iova; - size = iova_align(iovad, size + iova_off); + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { + iova_off = iova_offset(&cookie->iovad, phys); + size = iova_align(&cookie->iovad, size + iova_off); + } On 04/13/2017 06:21 AM, Robin Murphy wrote: > Hi Nate, > > On 13/04/17 09:55, Nate Watterson wrote: >> Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} >> making them unsuitable for use with iommu_domains having an IOMMU_DMA_MSI >> cookie since the cookie's iova_domain member, iovad, is uninitialized. >> >> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless >> of cookie type, failures are being seen when mapping MSI target >> addresses for devices attached to UNMANAGED domains. To work around >> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is >> initialized to the value returned by cookie_msi_granule(). > Oh bum. Thanks for the report. > > However, I really don't like bodging around it with deliberate undefined > behaviour. Fixing things properly doesn't seem too hard: > > ----->8----- > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 8348f366ddd1..62618e77bedc 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct > iommu_dma_cookie *cookie, > dma_addr_t iova, size_t size) > { > struct iova_domain *iovad = &cookie->iovad; > - unsigned long shift = iova_shift(iovad); > > /* The MSI case is only ever cleaning up its most recent > allocation */ > if (cookie->type == IOMMU_DMA_MSI_COOKIE) > cookie->msi_iova -= size; > else > - free_iova_fast(iovad, iova >> shift, size >> shift); > + free_iova_fast(iovad, iova_pfn(iovad, iova), > + size >> iova_shift(iovad)); > } > > static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t > dma_addr, > @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device > *dev, phys_addr_t phys, > { > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > struct iommu_dma_cookie *cookie = domain->iova_cookie; > - struct iova_domain *iovad = &cookie->iovad; > - size_t iova_off = iova_offset(iovad, phys); > + size_t iova_off = 0; > dma_addr_t iova; > > - size = iova_align(iovad, size + iova_off); > + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { > + iova_off = iova_offset(&cookie->iovad, phys); > + size = iova_align(&cookie->iovad, size + iova_off); > + } > + > iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev); > if (!iova) > return DMA_ERROR_CODE; > -----8<----- > > Untested, and you'll probably want to double-check it anyway given that > the original oversight was mine in the first place ;) > > Robin. > >> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") >> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> >> --- >> drivers/iommu/dma-iommu.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >> index 8348f366..d7b0816 100644 >> --- a/drivers/iommu/dma-iommu.c >> +++ b/drivers/iommu/dma-iommu.c >> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) >> >> cookie->msi_iova = base; >> domain->iova_cookie = cookie; >> + >> + /* >> + * Setup granule for compatibility with __iommu_dma_{alloc/free} and >> + * add a compile time check to ensure that writing granule won't >> + * clobber msi_iova. >> + */ >> + cookie->iovad.granule = cookie_msi_granule(cookie); >> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < >> + sizeof(cookie->msi_iova)); >> + >> return 0; >> } >> EXPORT_SYMBOL(iommu_get_msi_cookie); >> -- Shanker Donthineni Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-04-13 14:29 ` Shanker Donthineni @ 2017-05-04 13:32 ` Bharat Bhushan 0 siblings, 0 replies; 8+ messages in thread From: Bharat Bhushan @ 2017-05-04 13:32 UTC (permalink / raw) To: shankerd, Robin Murphy, Nate Watterson, Joerg Roedel, iommu, linux-kernel Hi Robin, I faced same issue on our platform and debugged to get the root cause of the issue. Also fixed in somewhat similar way, cleared iova_off and not change size for if cookie->type is IOMMU_DMA_MSI_COOKIE. Anyways that was not as good as below changes. While just now I saw this was already discussed and solved. Should have looked earlier to save time, but the debugging was some learning experience 😊 I have tested your below change and it works fine on NXP platform. Thanks -Bharat > -----Original Message----- > From: iommu-bounces@lists.linux-foundation.org [mailto:iommu- > bounces@lists.linux-foundation.org] On Behalf Of Shanker Donthineni > Sent: Thursday, April 13, 2017 8:00 PM > To: Robin Murphy <robin.murphy@arm.com>; Nate Watterson > <nwatters@codeaurora.org>; Joerg Roedel <joro@8bytes.org>; > iommu@lists.linux-foundation.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH] iommu/dma: Setup iova_domain granule for > IOMMU_DMA_MSI cookies > > Hi Robin, > > I tested your changes and the device pass-through feature works fine on > QDF2400 server platform. Maybe Nate comments on the patch contents but > it fixes the problem. > > > @@ -317,13 +317,13 @@ static void iommu_dma_free_iova(struct > iommu_dma_cookie *cookie, > dma_addr_t iova, size_t size) { > struct iova_domain *iovad = &cookie->iovad; > - unsigned long shift = iova_shift(iovad); > > /* The MSI case is only ever cleaning up its most recent allocation */ > if (cookie->type == IOMMU_DMA_MSI_COOKIE) > cookie->msi_iova -= size; > else > - free_iova_fast(iovad, iova >> shift, size >> shift); > + free_iova_fast(iovad, iova_pfn(iovad, iova), > + size >> iova_shift(iovad)); > } > > static void __iommu_dma_unmap(struct iommu_domain *domain, > dma_addr_t dma_addr, @@ -538,11 +538,14 @@ static dma_addr_t > __iommu_dma_map(struct device *dev, phys_addr_t phys, { > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > struct iommu_dma_cookie *cookie = domain->iova_cookie; > - struct iova_domain *iovad = &cookie->iovad; > - size_t iova_off = iova_offset(iovad, phys); > + size_t iova_off = 0; > dma_addr_t iova; > > - size = iova_align(iovad, size + iova_off); > + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { > + iova_off = iova_offset(&cookie->iovad, phys); > + size = iova_align(&cookie->iovad, size + iova_off); > + } > > > On 04/13/2017 06:21 AM, Robin Murphy wrote: > > Hi Nate, > > > > On 13/04/17 09:55, Nate Watterson wrote: > >> Currently, the __iommu_dma_{map/free} functions call > >> iova_{offset/align} making them unsuitable for use with iommu_domains > >> having an IOMMU_DMA_MSI cookie since the cookie's iova_domain > member, iovad, is uninitialized. > >> > >> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() > regardless > >> of cookie type, failures are being seen when mapping MSI target > >> addresses for devices attached to UNMANAGED domains. To work > around > >> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is > >> initialized to the value returned by cookie_msi_granule(). > > Oh bum. Thanks for the report. > > > > However, I really don't like bodging around it with deliberate > > undefined behaviour. Fixing things properly doesn't seem too hard: > > > > ----->8----- > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > > index 8348f366ddd1..62618e77bedc 100644 > > --- a/drivers/iommu/dma-iommu.c > > +++ b/drivers/iommu/dma-iommu.c > > @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct > > iommu_dma_cookie *cookie, > > dma_addr_t iova, size_t size) { > > struct iova_domain *iovad = &cookie->iovad; > > - unsigned long shift = iova_shift(iovad); > > > > /* The MSI case is only ever cleaning up its most recent > > allocation */ > > if (cookie->type == IOMMU_DMA_MSI_COOKIE) > > cookie->msi_iova -= size; > > else > > - free_iova_fast(iovad, iova >> shift, size >> shift); > > + free_iova_fast(iovad, iova_pfn(iovad, iova), > > + size >> iova_shift(iovad)); > > } > > > > static void __iommu_dma_unmap(struct iommu_domain *domain, > dma_addr_t > > dma_addr, @@ -617,11 +617,14 @@ static dma_addr_t > > __iommu_dma_map(struct device *dev, phys_addr_t phys, { > > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > > struct iommu_dma_cookie *cookie = domain->iova_cookie; > > - struct iova_domain *iovad = &cookie->iovad; > > - size_t iova_off = iova_offset(iovad, phys); > > + size_t iova_off = 0; > > dma_addr_t iova; > > > > - size = iova_align(iovad, size + iova_off); > > + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { > > + iova_off = iova_offset(&cookie->iovad, phys); > > + size = iova_align(&cookie->iovad, size + iova_off); > > + } > > + > > iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), > dev); > > if (!iova) > > return DMA_ERROR_CODE; > > -----8<----- > > > > Untested, and you'll probably want to double-check it anyway given > > that the original oversight was mine in the first place ;) > > > > Robin. > > > >> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") > >> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> > >> --- > >> drivers/iommu/dma-iommu.c | 10 ++++++++++ > >> 1 file changed, 10 insertions(+) > >> > >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > >> index 8348f366..d7b0816 100644 > >> --- a/drivers/iommu/dma-iommu.c > >> +++ b/drivers/iommu/dma-iommu.c > >> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct > iommu_domain > >> *domain, dma_addr_t base) > >> > >> cookie->msi_iova = base; > >> domain->iova_cookie = cookie; > >> + > >> + /* > >> + * Setup granule for compatibility with __iommu_dma_{alloc/free} > and > >> + * add a compile time check to ensure that writing granule won't > >> + * clobber msi_iova. > >> + */ > >> + cookie->iovad.granule = cookie_msi_granule(cookie); > >> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < > >> + sizeof(cookie->msi_iova)); > >> + > >> return 0; > >> } > >> EXPORT_SYMBOL(iommu_get_msi_cookie); > >> > > -- > Shanker Donthineni > Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm > Technologies, Inc. > Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux > Foundation Collaborative Project. > > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-04-13 11:21 ` Robin Murphy 2017-04-13 14:29 ` Shanker Donthineni @ 2017-04-13 19:38 ` Nate Watterson 2017-05-16 19:55 ` Auger Eric 1 sibling, 1 reply; 8+ messages in thread From: Nate Watterson @ 2017-04-13 19:38 UTC (permalink / raw) To: Robin Murphy, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd Hi Robin, On 4/13/2017 7:21 AM, Robin Murphy wrote: > Hi Nate, > > On 13/04/17 09:55, Nate Watterson wrote: >> Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} >> making them unsuitable for use with iommu_domains having an IOMMU_DMA_MSI >> cookie since the cookie's iova_domain member, iovad, is uninitialized. >> >> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless >> of cookie type, failures are being seen when mapping MSI target >> addresses for devices attached to UNMANAGED domains. To work around >> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is >> initialized to the value returned by cookie_msi_granule(). > > Oh bum. Thanks for the report. > > However, I really don't like bodging around it with deliberate undefined > behaviour. Fixing things properly doesn't seem too hard: I was not especially please with my solution, but I wanted to avoid potentially missing any other spots in the code where granule was used uninitialized. The compile time check made me feel a little less dirty about innappropriately using the iova_domain with MSI cookies. > > ----->8----- > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 8348f366ddd1..62618e77bedc 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct > iommu_dma_cookie *cookie, > dma_addr_t iova, size_t size) > { > struct iova_domain *iovad = &cookie->iovad; > - unsigned long shift = iova_shift(iovad); > > /* The MSI case is only ever cleaning up its most recent > allocation */ > if (cookie->type == IOMMU_DMA_MSI_COOKIE) > cookie->msi_iova -= size; > else > - free_iova_fast(iovad, iova >> shift, size >> shift); > + free_iova_fast(iovad, iova_pfn(iovad, iova), > + size >> iova_shift(iovad)); > } > > static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t > dma_addr, > @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device > *dev, phys_addr_t phys, > { > struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > struct iommu_dma_cookie *cookie = domain->iova_cookie; > - struct iova_domain *iovad = &cookie->iovad; > - size_t iova_off = iova_offset(iovad, phys); > + size_t iova_off = 0; > dma_addr_t iova; > > - size = iova_align(iovad, size + iova_off); > + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { > + iova_off = iova_offset(&cookie->iovad, phys); > + size = iova_align(&cookie->iovad, size + iova_off); > + } > + > iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), dev); > if (!iova) > return DMA_ERROR_CODE; > -----8<----- > > Untested, and you'll probably want to double-check it anyway given that > the original oversight was mine in the first place ;) This looks good to me. As Shanker has already mentioned, it does fix the faults we were previously seeing with direct device assignment. I also verified that there aren't any other obvious cases of a granule == 0 being used in the dma_iommu code by adding BUG_ON(!iovad->granule) to iova_{mask/align/offset/...} and running a variety of tests without issue. Are you going to post the patch? > > Robin. > >> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") >> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> >> --- >> drivers/iommu/dma-iommu.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >> index 8348f366..d7b0816 100644 >> --- a/drivers/iommu/dma-iommu.c >> +++ b/drivers/iommu/dma-iommu.c >> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) >> >> cookie->msi_iova = base; >> domain->iova_cookie = cookie; >> + >> + /* >> + * Setup granule for compatibility with __iommu_dma_{alloc/free} and >> + * add a compile time check to ensure that writing granule won't >> + * clobber msi_iova. >> + */ >> + cookie->iovad.granule = cookie_msi_granule(cookie); >> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < >> + sizeof(cookie->msi_iova)); >> + >> return 0; >> } >> EXPORT_SYMBOL(iommu_get_msi_cookie); >> > -- Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-04-13 19:38 ` Nate Watterson @ 2017-05-16 19:55 ` Auger Eric 2017-05-16 20:07 ` Nate Watterson 0 siblings, 1 reply; 8+ messages in thread From: Auger Eric @ 2017-05-16 19:55 UTC (permalink / raw) To: Nate Watterson, Robin Murphy, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd Hi, On 13/04/2017 21:38, Nate Watterson wrote: > Hi Robin, > > On 4/13/2017 7:21 AM, Robin Murphy wrote: >> Hi Nate, >> >> On 13/04/17 09:55, Nate Watterson wrote: >>> Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} >>> making them unsuitable for use with iommu_domains having an >>> IOMMU_DMA_MSI >>> cookie since the cookie's iova_domain member, iovad, is uninitialized. >>> >>> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless >>> of cookie type, failures are being seen when mapping MSI target >>> addresses for devices attached to UNMANAGED domains. To work around >>> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is >>> initialized to the value returned by cookie_msi_granule(). >> >> Oh bum. Thanks for the report. >> >> However, I really don't like bodging around it with deliberate undefined >> behaviour. Fixing things properly doesn't seem too hard: > > I was not especially please with my solution, but I wanted to avoid > potentially missing any other spots in the code where granule was > used uninitialized. The compile time check made me feel a little > less dirty about innappropriately using the iova_domain with MSI > cookies. > >> >> ----->8----- >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >> index 8348f366ddd1..62618e77bedc 100644 >> --- a/drivers/iommu/dma-iommu.c >> +++ b/drivers/iommu/dma-iommu.c >> @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct >> iommu_dma_cookie *cookie, >> dma_addr_t iova, size_t size) >> { >> struct iova_domain *iovad = &cookie->iovad; >> - unsigned long shift = iova_shift(iovad); >> >> /* The MSI case is only ever cleaning up its most recent >> allocation */ >> if (cookie->type == IOMMU_DMA_MSI_COOKIE) >> cookie->msi_iova -= size; >> else >> - free_iova_fast(iovad, iova >> shift, size >> shift); >> + free_iova_fast(iovad, iova_pfn(iovad, iova), >> + size >> iova_shift(iovad)); >> } >> >> static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t >> dma_addr, >> @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device >> *dev, phys_addr_t phys, >> { >> struct iommu_domain *domain = iommu_get_domain_for_dev(dev); >> struct iommu_dma_cookie *cookie = domain->iova_cookie; >> - struct iova_domain *iovad = &cookie->iovad; >> - size_t iova_off = iova_offset(iovad, phys); >> + size_t iova_off = 0; >> dma_addr_t iova; >> >> - size = iova_align(iovad, size + iova_off); >> + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { >> + iova_off = iova_offset(&cookie->iovad, phys); >> + size = iova_align(&cookie->iovad, size + iova_off); >> + } >> + >> iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), >> dev); >> if (!iova) >> return DMA_ERROR_CODE; >> -----8<----- >> >> Untested, and you'll probably want to double-check it anyway given that >> the original oversight was mine in the first place ;) > > This looks good to me. As Shanker has already mentioned, it does fix the > faults we were previously seeing with direct device assignment. I also > verified that there aren't any other obvious cases of a granule == 0 > being used in the dma_iommu code by adding BUG_ON(!iovad->granule) to > iova_{mask/align/offset/...} and running a variety of tests without > issue. > > Are you going to post the patch? I also noticed PCIe passthrough/ARM is broken for me with 4.12-r1. I tested Robin's patch as well, on Cavium ThunderX, and this fixes the faults I have seen. Has anyone sent a formal patch? Thanks Eric > >> >> Robin. >> >>> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") >>> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> >>> --- >>> drivers/iommu/dma-iommu.c | 10 ++++++++++ >>> 1 file changed, 10 insertions(+) >>> >>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >>> index 8348f366..d7b0816 100644 >>> --- a/drivers/iommu/dma-iommu.c >>> +++ b/drivers/iommu/dma-iommu.c >>> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain >>> *domain, dma_addr_t base) >>> cookie->msi_iova = base; >>> domain->iova_cookie = cookie; >>> + >>> + /* >>> + * Setup granule for compatibility with __iommu_dma_{alloc/free} >>> and >>> + * add a compile time check to ensure that writing granule won't >>> + * clobber msi_iova. >>> + */ >>> + cookie->iovad.granule = cookie_msi_granule(cookie); >>> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < >>> + sizeof(cookie->msi_iova)); >>> + >>> return 0; >>> } >>> EXPORT_SYMBOL(iommu_get_msi_cookie); >>> >> ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-05-16 19:55 ` Auger Eric @ 2017-05-16 20:07 ` Nate Watterson 2017-05-16 20:20 ` Auger Eric 0 siblings, 1 reply; 8+ messages in thread From: Nate Watterson @ 2017-05-16 20:07 UTC (permalink / raw) To: Auger Eric, Robin Murphy, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd On 5/16/2017 3:55 PM, Auger Eric wrote: > Hi, > > On 13/04/2017 21:38, Nate Watterson wrote: >> Hi Robin, >> >> On 4/13/2017 7:21 AM, Robin Murphy wrote: >>> Hi Nate, >>> >>> On 13/04/17 09:55, Nate Watterson wrote: >>>> Currently, the __iommu_dma_{map/free} functions call iova_{offset/align} >>>> making them unsuitable for use with iommu_domains having an >>>> IOMMU_DMA_MSI >>>> cookie since the cookie's iova_domain member, iovad, is uninitialized. >>>> >>>> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless >>>> of cookie type, failures are being seen when mapping MSI target >>>> addresses for devices attached to UNMANAGED domains. To work around >>>> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is >>>> initialized to the value returned by cookie_msi_granule(). >>> >>> Oh bum. Thanks for the report. >>> >>> However, I really don't like bodging around it with deliberate undefined >>> behaviour. Fixing things properly doesn't seem too hard: >> >> I was not especially please with my solution, but I wanted to avoid >> potentially missing any other spots in the code where granule was >> used uninitialized. The compile time check made me feel a little >> less dirty about innappropriately using the iova_domain with MSI >> cookies. >> >>> >>> ----->8----- >>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >>> index 8348f366ddd1..62618e77bedc 100644 >>> --- a/drivers/iommu/dma-iommu.c >>> +++ b/drivers/iommu/dma-iommu.c >>> @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct >>> iommu_dma_cookie *cookie, >>> dma_addr_t iova, size_t size) >>> { >>> struct iova_domain *iovad = &cookie->iovad; >>> - unsigned long shift = iova_shift(iovad); >>> >>> /* The MSI case is only ever cleaning up its most recent >>> allocation */ >>> if (cookie->type == IOMMU_DMA_MSI_COOKIE) >>> cookie->msi_iova -= size; >>> else >>> - free_iova_fast(iovad, iova >> shift, size >> shift); >>> + free_iova_fast(iovad, iova_pfn(iovad, iova), >>> + size >> iova_shift(iovad)); >>> } >>> >>> static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t >>> dma_addr, >>> @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device >>> *dev, phys_addr_t phys, >>> { >>> struct iommu_domain *domain = iommu_get_domain_for_dev(dev); >>> struct iommu_dma_cookie *cookie = domain->iova_cookie; >>> - struct iova_domain *iovad = &cookie->iovad; >>> - size_t iova_off = iova_offset(iovad, phys); >>> + size_t iova_off = 0; >>> dma_addr_t iova; >>> >>> - size = iova_align(iovad, size + iova_off); >>> + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { >>> + iova_off = iova_offset(&cookie->iovad, phys); >>> + size = iova_align(&cookie->iovad, size + iova_off); >>> + } >>> + >>> iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), >>> dev); >>> if (!iova) >>> return DMA_ERROR_CODE; >>> -----8<----- >>> >>> Untested, and you'll probably want to double-check it anyway given that >>> the original oversight was mine in the first place ;) >> >> This looks good to me. As Shanker has already mentioned, it does fix the >> faults we were previously seeing with direct device assignment. I also >> verified that there aren't any other obvious cases of a granule == 0 >> being used in the dma_iommu code by adding BUG_ON(!iovad->granule) to >> iova_{mask/align/offset/...} and running a variety of tests without >> issue. >> >> Are you going to post the patch? > > I also noticed PCIe passthrough/ARM is broken for me with 4.12-r1. I > tested Robin's patch as well, on Cavium ThunderX, and this fixes the > faults I have seen. > > Has anyone sent a formal patch? iommu/dma: Don't touch invalid iova_domain members > > Thanks > > Eric > >> >>> >>> Robin. >>> >>>> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") >>>> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> >>>> --- >>>> drivers/iommu/dma-iommu.c | 10 ++++++++++ >>>> 1 file changed, 10 insertions(+) >>>> >>>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >>>> index 8348f366..d7b0816 100644 >>>> --- a/drivers/iommu/dma-iommu.c >>>> +++ b/drivers/iommu/dma-iommu.c >>>> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain >>>> *domain, dma_addr_t base) >>>> cookie->msi_iova = base; >>>> domain->iova_cookie = cookie; >>>> + >>>> + /* >>>> + * Setup granule for compatibility with __iommu_dma_{alloc/free} >>>> and >>>> + * add a compile time check to ensure that writing granule won't >>>> + * clobber msi_iova. >>>> + */ >>>> + cookie->iovad.granule = cookie_msi_granule(cookie); >>>> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < >>>> + sizeof(cookie->msi_iova)); >>>> + >>>> return 0; >>>> } >>>> EXPORT_SYMBOL(iommu_get_msi_cookie); >>>> >>> -- Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies 2017-05-16 20:07 ` Nate Watterson @ 2017-05-16 20:20 ` Auger Eric 0 siblings, 0 replies; 8+ messages in thread From: Auger Eric @ 2017-05-16 20:20 UTC (permalink / raw) To: Nate Watterson, Robin Murphy, Joerg Roedel, iommu, linux-kernel; +Cc: shankerd Hi Nate, On 16/05/2017 22:07, Nate Watterson wrote: > > > On 5/16/2017 3:55 PM, Auger Eric wrote: >> Hi, >> >> On 13/04/2017 21:38, Nate Watterson wrote: >>> Hi Robin, >>> >>> On 4/13/2017 7:21 AM, Robin Murphy wrote: >>>> Hi Nate, >>>> >>>> On 13/04/17 09:55, Nate Watterson wrote: >>>>> Currently, the __iommu_dma_{map/free} functions call >>>>> iova_{offset/align} >>>>> making them unsuitable for use with iommu_domains having an >>>>> IOMMU_DMA_MSI >>>>> cookie since the cookie's iova_domain member, iovad, is uninitialized. >>>>> >>>>> Now that iommu_dma_get_msi_page() calls __iommu_dma_map() regardless >>>>> of cookie type, failures are being seen when mapping MSI target >>>>> addresses for devices attached to UNMANAGED domains. To work around >>>>> this issue, the iova_domain granule for IOMMU_DMA_MSI cookies is >>>>> initialized to the value returned by cookie_msi_granule(). >>>> >>>> Oh bum. Thanks for the report. >>>> >>>> However, I really don't like bodging around it with deliberate >>>> undefined >>>> behaviour. Fixing things properly doesn't seem too hard: >>> >>> I was not especially please with my solution, but I wanted to avoid >>> potentially missing any other spots in the code where granule was >>> used uninitialized. The compile time check made me feel a little >>> less dirty about innappropriately using the iova_domain with MSI >>> cookies. >>> >>>> >>>> ----->8----- >>>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >>>> index 8348f366ddd1..62618e77bedc 100644 >>>> --- a/drivers/iommu/dma-iommu.c >>>> +++ b/drivers/iommu/dma-iommu.c >>>> @@ -396,13 +396,13 @@ static void iommu_dma_free_iova(struct >>>> iommu_dma_cookie *cookie, >>>> dma_addr_t iova, size_t size) >>>> { >>>> struct iova_domain *iovad = &cookie->iovad; >>>> - unsigned long shift = iova_shift(iovad); >>>> >>>> /* The MSI case is only ever cleaning up its most recent >>>> allocation */ >>>> if (cookie->type == IOMMU_DMA_MSI_COOKIE) >>>> cookie->msi_iova -= size; >>>> else >>>> - free_iova_fast(iovad, iova >> shift, size >> shift); >>>> + free_iova_fast(iovad, iova_pfn(iovad, iova), >>>> + size >> iova_shift(iovad)); >>>> } >>>> >>>> static void __iommu_dma_unmap(struct iommu_domain *domain, >>>> dma_addr_t >>>> dma_addr, >>>> @@ -617,11 +617,14 @@ static dma_addr_t __iommu_dma_map(struct device >>>> *dev, phys_addr_t phys, >>>> { >>>> struct iommu_domain *domain = iommu_get_domain_for_dev(dev); >>>> struct iommu_dma_cookie *cookie = domain->iova_cookie; >>>> - struct iova_domain *iovad = &cookie->iovad; >>>> - size_t iova_off = iova_offset(iovad, phys); >>>> + size_t iova_off = 0; >>>> dma_addr_t iova; >>>> >>>> - size = iova_align(iovad, size + iova_off); >>>> + if (cookie->type == IOMMU_DMA_IOVA_COOKIE) { >>>> + iova_off = iova_offset(&cookie->iovad, phys); >>>> + size = iova_align(&cookie->iovad, size + iova_off); >>>> + } >>>> + >>>> iova = iommu_dma_alloc_iova(domain, size, dma_get_mask(dev), >>>> dev); >>>> if (!iova) >>>> return DMA_ERROR_CODE; >>>> -----8<----- >>>> >>>> Untested, and you'll probably want to double-check it anyway given that >>>> the original oversight was mine in the first place ;) >>> >>> This looks good to me. As Shanker has already mentioned, it does fix the >>> faults we were previously seeing with direct device assignment. I also >>> verified that there aren't any other obvious cases of a granule == 0 >>> being used in the dma_iommu code by adding BUG_ON(!iovad->granule) to >>> iova_{mask/align/offset/...} and running a variety of tests without >>> issue. >>> >>> Are you going to post the patch? >> >> I also noticed PCIe passthrough/ARM is broken for me with 4.12-r1. I >> tested Robin's patch as well, on Cavium ThunderX, and this fixes the >> faults I have seen. >> >> Has anyone sent a formal patch? > > iommu/dma: Don't touch invalid iova_domain members thanks! Best Regards Eric > >> >> Thanks >> >> Eric >> >>> >>>> >>>> Robin. >>>> >>>>> Fixes: a44e6657585b ("iommu/dma: Clean up MSI IOVA allocation") >>>>> Signed-off-by: Nate Watterson <nwatters@codeaurora.org> >>>>> --- >>>>> drivers/iommu/dma-iommu.c | 10 ++++++++++ >>>>> 1 file changed, 10 insertions(+) >>>>> >>>>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >>>>> index 8348f366..d7b0816 100644 >>>>> --- a/drivers/iommu/dma-iommu.c >>>>> +++ b/drivers/iommu/dma-iommu.c >>>>> @@ -127,6 +127,16 @@ int iommu_get_msi_cookie(struct iommu_domain >>>>> *domain, dma_addr_t base) >>>>> cookie->msi_iova = base; >>>>> domain->iova_cookie = cookie; >>>>> + >>>>> + /* >>>>> + * Setup granule for compatibility with __iommu_dma_{alloc/free} >>>>> and >>>>> + * add a compile time check to ensure that writing granule won't >>>>> + * clobber msi_iova. >>>>> + */ >>>>> + cookie->iovad.granule = cookie_msi_granule(cookie); >>>>> + BUILD_BUG_ON(offsetof(struct iova_domain, granule) < >>>>> + sizeof(cookie->msi_iova)); >>>>> + >>>>> return 0; >>>>> } >>>>> EXPORT_SYMBOL(iommu_get_msi_cookie); >>>>> >>>> > ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2017-05-16 20:21 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2017-04-13 8:55 [PATCH] iommu/dma: Setup iova_domain granule for IOMMU_DMA_MSI cookies Nate Watterson 2017-04-13 11:21 ` Robin Murphy 2017-04-13 14:29 ` Shanker Donthineni 2017-05-04 13:32 ` Bharat Bhushan 2017-04-13 19:38 ` Nate Watterson 2017-05-16 19:55 ` Auger Eric 2017-05-16 20:07 ` Nate Watterson 2017-05-16 20:20 ` Auger Eric
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