From: Joerg Roedel <joro@8bytes.org> To: Lu Baolu <baolu.lu@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org>, jroedel@suse.de, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/5 v2] iommu/vt-d: Do deferred attachment in iommu_need_mapping() Date: Tue, 18 Feb 2020 10:28:27 +0100 [thread overview] Message-ID: <20200218092827.tp3pq67adzr56k7e@8bytes.org> (raw) In-Reply-To: <83b21e50-9097-06db-d404-8fe400134bac@linux.intel.com> Hi Baolu, On Tue, Feb 18, 2020 at 10:38:14AM +0800, Lu Baolu wrote: > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > > index 42cdcce1602e..32f43695a22b 100644 > > --- a/drivers/iommu/intel-iommu.c > > +++ b/drivers/iommu/intel-iommu.c > > @@ -2541,9 +2541,6 @@ static void do_deferred_attach(struct device *dev) > > static struct dmar_domain *deferred_attach_domain(struct device *dev) > > { > > - if (unlikely(attach_deferred(dev))) > > - do_deferred_attach(dev); > > - > > This should also be moved to the call place of deferred_attach_domain() > in bounce_map_single(). > > bounce_map_single() assumes that devices always use DMA domain, so it > doesn't call iommu_need_mapping(). We could do_deferred_attach() there > manually. Good point, thanks for your review. Updated patch below. From 3a5b8a66d288d86ac1fd45092e7d96f842d0cccf Mon Sep 17 00:00:00 2001 From: Joerg Roedel <jroedel@suse.de> Date: Mon, 17 Feb 2020 17:20:59 +0100 Subject: [PATCH 3/5] iommu/vt-d: Do deferred attachment in iommu_need_mapping() The attachment of deferred devices needs to happen before the check whether the device is identity mapped or not. Otherwise the check will return wrong results, cause warnings boot failures in kdump kernels, like WARNING: CPU: 0 PID: 318 at ../drivers/iommu/intel-iommu.c:592 domain_get_iommu+0x61/0x70 [...] Call Trace: __intel_map_single+0x55/0x190 intel_alloc_coherent+0xac/0x110 dmam_alloc_attrs+0x50/0xa0 ahci_port_start+0xfb/0x1f0 [libahci] ata_host_start.part.39+0x104/0x1e0 [libata] With the earlier check the kdump boot succeeds and a crashdump is written. Signed-off-by: Joerg Roedel <jroedel@suse.de> --- drivers/iommu/intel-iommu.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 42cdcce1602e..723f615c6e84 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -2541,9 +2541,6 @@ static void do_deferred_attach(struct device *dev) static struct dmar_domain *deferred_attach_domain(struct device *dev) { - if (unlikely(attach_deferred(dev))) - do_deferred_attach(dev); - return find_domain(dev); } @@ -3595,6 +3592,9 @@ static bool iommu_need_mapping(struct device *dev) if (iommu_dummy(dev)) return false; + if (unlikely(attach_deferred(dev))) + do_deferred_attach(dev); + ret = identity_mapping(dev); if (ret) { u64 dma_mask = *dev->dma_mask; @@ -3958,7 +3958,11 @@ bounce_map_single(struct device *dev, phys_addr_t paddr, size_t size, int prot = 0; int ret; + if (unlikely(attach_deferred(dev))) + do_deferred_attach(dev); + domain = deferred_attach_domain(dev); + if (WARN_ON(dir == DMA_NONE || !domain)) return DMA_MAPPING_ERROR; -- 2.25.0
WARNING: multiple messages have this Message-ID (diff)
From: Joerg Roedel <joro@8bytes.org> To: Lu Baolu <baolu.lu@linux.intel.com> Cc: iommu@lists.linux-foundation.org, jroedel@suse.de, David Woodhouse <dwmw2@infradead.org>, linux-kernel@vger.kernel.org Subject: [PATCH 3/5 v2] iommu/vt-d: Do deferred attachment in iommu_need_mapping() Date: Tue, 18 Feb 2020 10:28:27 +0100 [thread overview] Message-ID: <20200218092827.tp3pq67adzr56k7e@8bytes.org> (raw) In-Reply-To: <83b21e50-9097-06db-d404-8fe400134bac@linux.intel.com> Hi Baolu, On Tue, Feb 18, 2020 at 10:38:14AM +0800, Lu Baolu wrote: > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > > index 42cdcce1602e..32f43695a22b 100644 > > --- a/drivers/iommu/intel-iommu.c > > +++ b/drivers/iommu/intel-iommu.c > > @@ -2541,9 +2541,6 @@ static void do_deferred_attach(struct device *dev) > > static struct dmar_domain *deferred_attach_domain(struct device *dev) > > { > > - if (unlikely(attach_deferred(dev))) > > - do_deferred_attach(dev); > > - > > This should also be moved to the call place of deferred_attach_domain() > in bounce_map_single(). > > bounce_map_single() assumes that devices always use DMA domain, so it > doesn't call iommu_need_mapping(). We could do_deferred_attach() there > manually. Good point, thanks for your review. Updated patch below. From 3a5b8a66d288d86ac1fd45092e7d96f842d0cccf Mon Sep 17 00:00:00 2001 From: Joerg Roedel <jroedel@suse.de> Date: Mon, 17 Feb 2020 17:20:59 +0100 Subject: [PATCH 3/5] iommu/vt-d: Do deferred attachment in iommu_need_mapping() The attachment of deferred devices needs to happen before the check whether the device is identity mapped or not. Otherwise the check will return wrong results, cause warnings boot failures in kdump kernels, like WARNING: CPU: 0 PID: 318 at ../drivers/iommu/intel-iommu.c:592 domain_get_iommu+0x61/0x70 [...] Call Trace: __intel_map_single+0x55/0x190 intel_alloc_coherent+0xac/0x110 dmam_alloc_attrs+0x50/0xa0 ahci_port_start+0xfb/0x1f0 [libahci] ata_host_start.part.39+0x104/0x1e0 [libata] With the earlier check the kdump boot succeeds and a crashdump is written. Signed-off-by: Joerg Roedel <jroedel@suse.de> --- drivers/iommu/intel-iommu.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 42cdcce1602e..723f615c6e84 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -2541,9 +2541,6 @@ static void do_deferred_attach(struct device *dev) static struct dmar_domain *deferred_attach_domain(struct device *dev) { - if (unlikely(attach_deferred(dev))) - do_deferred_attach(dev); - return find_domain(dev); } @@ -3595,6 +3592,9 @@ static bool iommu_need_mapping(struct device *dev) if (iommu_dummy(dev)) return false; + if (unlikely(attach_deferred(dev))) + do_deferred_attach(dev); + ret = identity_mapping(dev); if (ret) { u64 dma_mask = *dev->dma_mask; @@ -3958,7 +3958,11 @@ bounce_map_single(struct device *dev, phys_addr_t paddr, size_t size, int prot = 0; int ret; + if (unlikely(attach_deferred(dev))) + do_deferred_attach(dev); + domain = deferred_attach_domain(dev); + if (WARN_ON(dir == DMA_NONE || !domain)) return DMA_MAPPING_ERROR; -- 2.25.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2020-02-18 9:28 UTC|newest] Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-02-17 19:38 [PATCH 0/5] iommu/vt-d: Fix kdump boot with VT-d enabled Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:38 ` [PATCH 1/5] iommu/vt-d: Add attach_deferred() helper Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:50 ` Jerry Snitselaar 2020-02-17 19:50 ` Jerry Snitselaar 2020-02-18 17:14 ` Christoph Hellwig 2020-02-18 17:14 ` Christoph Hellwig 2020-02-19 9:29 ` Joerg Roedel 2020-02-19 9:29 ` Joerg Roedel 2020-02-17 19:38 ` [PATCH 2/5] iommu/vt-d: Move deferred device attachment into helper function Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:50 ` Jerry Snitselaar 2020-02-17 19:50 ` Jerry Snitselaar 2020-02-18 17:16 ` Christoph Hellwig 2020-02-18 17:16 ` Christoph Hellwig 2020-02-17 19:38 ` [PATCH 3/5] iommu/vt-d: Do deferred attachment in iommu_need_mapping() Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:51 ` Jerry Snitselaar 2020-02-17 19:51 ` Jerry Snitselaar 2020-02-18 2:38 ` Lu Baolu 2020-02-18 2:38 ` Lu Baolu 2020-02-18 9:28 ` Joerg Roedel [this message] 2020-02-18 9:28 ` [PATCH 3/5 v2] " Joerg Roedel 2020-02-18 11:54 ` Lu Baolu 2020-02-18 11:54 ` Lu Baolu 2020-02-18 16:22 ` Joerg Roedel 2020-02-18 16:22 ` Joerg Roedel 2020-02-18 15:53 ` Jerry Snitselaar 2020-02-18 15:53 ` Jerry Snitselaar 2020-02-17 19:38 ` [PATCH 4/5] iommu/vt-d: Remove deferred_attach_domain() Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:51 ` Jerry Snitselaar 2020-02-17 19:51 ` Jerry Snitselaar 2020-02-17 19:38 ` [PATCH 5/5] iommu/vt-d: Simplify check in identity_mapping() Joerg Roedel 2020-02-17 19:38 ` Joerg Roedel 2020-02-17 19:54 ` Jerry Snitselaar 2020-02-17 19:54 ` Jerry Snitselaar
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200218092827.tp3pq67adzr56k7e@8bytes.org \ --to=joro@8bytes.org \ --cc=baolu.lu@linux.intel.com \ --cc=dwmw2@infradead.org \ --cc=iommu@lists.linux-foundation.org \ --cc=jroedel@suse.de \ --cc=linux-kernel@vger.kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.