| Message ID | 20220626045144.9063-1-jsnitsel@redhat.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] dmaengine: idxd: Only call idxd_enable_system_pasid() if succeeded in enabling SVA feature | expand |
Hi, Jerry, On Sat, Jun 25, 2022 at 09:51:44PM -0700, Jerry Snitselaar wrote: > On a Sapphire Rapids system if you boot without intel_iommu=on, the IDXD s/you// > driver will crash during probe in iommu_sva_bind_device(). .... > v2: Balance braces on if else block. Fix up commit description. This change log should be moved after "---". > > Fixes: 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling") > Cc: Vinod Koul <vkoul@kernel.org> > Cc: linux-kernel@vger.kernel.org > Cc: Dave Jiang <dave.jiang@intel.com> > Cc: Fenghua Yu <fenghua.yu@intel.com> > Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com> Please put the bug report link here: Link: https://lore.kernel.org/dmaengine/20220623170232.6whonfjuh3m5vcoy@cantor/ > --- i.e. put the change log here: v2: Balance braces on if else block. Fix up commit description. > drivers/dma/idxd/init.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c > index 355fb3ef4cbf..aa3478257ddb 100644 > --- a/drivers/dma/idxd/init.c > +++ b/drivers/dma/idxd/init.c > @@ -512,15 +512,16 @@ static int idxd_probe(struct idxd_device *idxd) > dev_dbg(dev, "IDXD reset complete\n"); > > if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) { > - if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) > + if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) { > dev_warn(dev, "Unable to turn on user SVA feature.\n"); > - else > + } else { > set_bit(IDXD_FLAG_USER_PASID_ENABLED, &idxd->flags); > > - if (idxd_enable_system_pasid(idxd)) > - dev_warn(dev, "No in-kernel DMA with PASID.\n"); > - else > - set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); > + if (idxd_enable_system_pasid(idxd)) > + dev_warn(dev, "No in-kernel DMA with PASID.\n"); > + else > + set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); > + } > } else if (!sva) { > dev_warn(dev, "User forced SVA off via module param.\n"); > } > -- > 2.36.1 > Thanks. -Fenghua
diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 355fb3ef4cbf..aa3478257ddb 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -512,15 +512,16 @@ static int idxd_probe(struct idxd_device *idxd) dev_dbg(dev, "IDXD reset complete\n"); if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) { - if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) + if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) { dev_warn(dev, "Unable to turn on user SVA feature.\n"); - else + } else { set_bit(IDXD_FLAG_USER_PASID_ENABLED, &idxd->flags); - if (idxd_enable_system_pasid(idxd)) - dev_warn(dev, "No in-kernel DMA with PASID.\n"); - else - set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + if (idxd_enable_system_pasid(idxd)) + dev_warn(dev, "No in-kernel DMA with PASID.\n"); + else + set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + } } else if (!sva) { dev_warn(dev, "User forced SVA off via module param.\n"); }
On a Sapphire Rapids system if you boot without intel_iommu=on, the IDXD driver will crash during probe in iommu_sva_bind_device(). [ 21.423729] BUG: kernel NULL pointer dereference, address: 0000000000000038 [ 21.445108] #PF: supervisor read access in kernel mode [ 21.450912] #PF: error_code(0x0000) - not-present page [ 21.456706] PGD 0 [ 21.459047] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 21.464004] CPU: 0 PID: 1420 Comm: kworker/0:3 Not tainted 5.19.0-0.rc3.27.eln120.x86_64 #1 [ 21.464011] Hardware name: Intel Corporation EAGLESTREAM/EAGLESTREAM, BIOS EGSDCRB1.SYS.0067.D12.2110190954 10/19/2021 [ 21.464015] Workqueue: events work_for_cpu_fn [ 21.464030] RIP: 0010:iommu_sva_bind_device+0x1d/0xe0 [ 21.464046] Code: c3 cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 49 89 d6 41 55 41 54 55 53 48 83 ec 08 48 8b 87 d8 02 00 00 <48> 8b 40 38 48 8b 50 10 48 83 7a 70 00 48 89 14 24 0f 84 91 00 00 [ 21.464050] RSP: 0018:ff7245d9096b7db8 EFLAGS: 00010296 [ 21.464054] RAX: 0000000000000000 RBX: ff1eadeec8a51000 RCX: 0000000000000000 [ 21.464058] RDX: ff7245d9096b7e24 RSI: 0000000000000000 RDI: ff1eadeec8a510d0 [ 21.464060] RBP: ff1eadeec8a51000 R08: ffffffffb1a12300 R09: ff1eadffbfce25b4 [ 21.464062] R10: ffffffffffffffff R11: 0000000000000038 R12: ffffffffc09f8000 [ 21.464065] R13: ff1eadeec8a510d0 R14: ff7245d9096b7e24 R15: ff1eaddf54429000 [ 21.464067] FS: 0000000000000000(0000) GS:ff1eadee7f600000(0000) knlGS:0000000000000000 [ 21.464070] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.464072] CR2: 0000000000000038 CR3: 00000008c0e10006 CR4: 0000000000771ef0 [ 21.464074] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.464076] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 21.464078] PKRU: 55555554 [ 21.464079] Call Trace: [ 21.464083] <TASK> [ 21.464092] idxd_pci_probe+0x259/0x1070 [idxd] [ 21.464121] local_pci_probe+0x3e/0x80 [ 21.464132] work_for_cpu_fn+0x13/0x20 [ 21.464136] process_one_work+0x1c4/0x380 [ 21.464143] worker_thread+0x1ab/0x380 [ 21.464147] ? _raw_spin_lock_irqsave+0x23/0x50 [ 21.464158] ? process_one_work+0x380/0x380 [ 21.464161] kthread+0xe6/0x110 [ 21.464168] ? kthread_complete_and_exit+0x20/0x20 [ 21.464172] ret_from_fork+0x1f/0x30 iommu_sva_bind_device() requires SVA has been enabled successfully on the IDXD device before it's called. Otherwise, iommu_sva_bind_device() will access a NULL pointer. If Intel IOMMU is disabled, SVA cannot be enabled and thus idxd_enable_system_pasid() and iommu_sva_bind_device() should not be called. v2: Balance braces on if else block. Fix up commit description. Fixes: 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling") Cc: Vinod Koul <vkoul@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: Dave Jiang <dave.jiang@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com> --- drivers/dma/idxd/init.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)