From mboxrd@z Thu Jan 1 00:00:00 1970 From: sricharan@codeaurora.org (Sricharan R) Date: Tue, 28 Mar 2017 10:23:30 +0530 Subject: [PATCH V9 00/11] IOMMU probe deferral support In-Reply-To: References: <1489086061-9356-1-git-send-email-sricharan@codeaurora.org> <58D49845.9060407@hisilicon.com> <0ea8022b-a19b-335d-6cc6-81510196f891@codeaurora.org> <5FC3163CFD30C246ABAA99954A238FA81750B7CB@lhreml504-mbs> <5FC3163CFD30C246ABAA99954A238FA81750CCC4@lhreml504-mbs> Message-ID: <8d7ba471-84d4-b9f3-9d2a-de166f6839d4@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, >>>> On 24/03/17 09:27, Shameerali Kolothum Thodi wrote: >>>>> Hi Sricharan, >>>>> >>>>>> -----Original Message----- >>>>>> From: Sricharan R [mailto:sricharan at codeaurora.org] >>> [...] >>>>>> Looks like this triggers the start of the bug. >>>>>> So the below check in iommu_dma_init_domain fails, >>>>>> >>>>>> if (domain->geometry.force_aperture) { >>>>>> if (base > domain->geometry.aperture_end || >>>>>> base + size <= domain->geometry.aperture_start) { >>>>>> >>>>>> and the rest goes out of sync after that. Can you print out the base, >>>>>> aperture_start and end values to see why the check fails ? >>>>> >>>>> dev_info(dev, "0x%llx 0x%llx, 0x%llx 0x%llx, 0x%llx 0x%llx\n", base, size, >>>> domain->geometry.aperture_start, domain->geometry.aperture_end, >>>> *dev->dma_mask, dev->coherent_dma_mask); >>>>> >>>>> [ 183.752100] ixgbevf 0000:81:10.0: 0x0 0x100000000, 0x0 0xffffffffffff, >>>> 0xffffffff 0xffffffff >>>>> ..... >>>>> [ 319.508037] vfio-pci 0000:81:10.0: 0x0 0x0, 0x0 0xffffffffffff, >>>> 0xffffffffffffffff 0xffffffffffffffff >>>>> >>>>> Yes, size seems to be the problem here. When the VF device gets >>> attached >>>> to vfio-pci, >>>>> somehow the dev->coherent_dma_mask is set to 64 bits and size >>> become >>>> zero. >>>> >>>> AFAICS, this is either down to patch 3 (which should apply on its own >>>> easily enough for testing), or patch 6, implying that somehow the >>>> vfio-pci device gets its DMA mask widened to 64 bits somewhere between >>>> very soon after after creation (where we originally called >>>> of_dma_configure()) and immediately before probe (where we now call >>> it). >>>> >>>> Either way I guess this is yet more motivation to write that "change the >>>> arch_setup_dma_ops() interface to take a mask instead of a size" patch... >>> >>> Just applying the patch 3 and binding the device into vfio-pci is fine. Please >>> find the >>> log below (with dev_info debug added to iommu_dma_init_domain ). >>> ... >>> [ 142.851906] iommu: Adding device 0000:81:10.0 to group 6 >>> [ 142.852063] ixgbevf 0000:81:10.0: 0x0 0x100000000, 0x0 0xffffffffffff, >>> 0xffffffff 0xffffffff ---->dev_info() >>> [ 142.852836] ixgbevf 0000:81:10.0: enabling device (0000 -> 0002) >>> [ 142.852962] ixgbe 0000:81:00.0 eth0: VF Reset msg received from vf 0 >>> [ 142.853833] ixgbe 0000:81:00.0: VF 0 has no MAC address assigned, you >>> may have to assign one manually >>> [ 142.863956] ixgbevf 0000:81:10.0: MAC address not assigned by >>> administrator. >>> [ 142.863960] ixgbevf 0000:81:10.0: Assigning random MAC address >>> [ 142.865689] ixgbevf 0000:81:10.0: da:9f:f8:1e:57:3a >>> [ 142.865692] ixgbevf 0000:81:10.0: MAC: 1 >>> [ 142.865693] ixgbevf 0000:81:10.0: Intel(R) 82599 Virtual Function >>> [ 142.939145] ixgbe 0000:81:00.0 eth0: NIC Link is Up 1 Gbps, Flow Control: >>> None >>> [ 152.902894] nfs: server 172.18.45.166 not responding, still trying >>> [ 188.980933] nfs: server 172.18.45.166 not responding, still trying >>> [ 188.981298] nfs: server 172.18.45.166 OK >>> [ 188.981593] nfs: server 172.18.45.166 OK >>> [ 221.755626] VFIO - User Level meta-driver version: 0.3 >>> ... >>> >>> Applied up to patch 6, and the issue appeared, >>> >>> [ 145.212351] iommu: Adding device 0000:81:10.0 to group 5 >>> [ 145.212367] ixgbevf 0000:81:10.0: 0x0 0x100000000, 0x0 0xffffffffffff, >>> 0xffffffff 0xffffffff >>> [ 145.213261] ixgbevf 0000:81:10.0: enabling device (0000 -> 0002) >>> [ 145.213394] ixgbe 0000:81:00.0 eth0: VF Reset msg received from vf 0 >>> [ 145.214272] ixgbe 0000:81:00.0: VF 0 has no MAC address assigned, you >>> may have to assign one manually >>> [ 145.224379] ixgbevf 0000:81:10.0: MAC address not assigned by >>> administrator. >>> [ 145.224384] ixgbevf 0000:81:10.0: Assigning random MAC address >>> [ 145.225941] ixgbevf 0000:81:10.0: 1a:85:06:48:a7:19 >>> [ 145.225944] ixgbevf 0000:81:10.0: MAC: 1 >>> [ 145.225946] ixgbevf 0000:81:10.0: Intel(R) 82599 Virtual Function >>> [ 145.299961] ixgbe 0000:81:00.0 eth0: NIC Link is Up 1 Gbps, Flow Control: >>> None >>> [ 154.947742] nfs: server 172.18.45.166 not responding, still trying >>> [ 191.025780] nfs: server 172.18.45.166 not responding, still trying >>> [ 191.026122] nfs: server 172.18.45.166 OK >>> [ 191.026317] nfs: server 172.18.45.166 OK >>> [ 263.706402] VFIO - User Level meta-driver version: 0.3 >>> [ 269.757613] vfio-pci 0000:81:10.0: 0x0 0x0, 0x0 0xffffffffffff, 0xffffffffffffffff >>> 0xffffffffffffffff >>> [ 269.757617] specified DMA range outside IOMMU capability >>> [ 269.757618] Failed to set up IOMMU for device 0000:81:10.0; retaining >>> platform DMA ops >>> >>> From the logs its clear that when ixgbevf driver originally probes and adds >>> the device >>> to smmu the dma mask is 32, but when it binds to vfio-pci, it becomes 64 bit. >> >> Just to add to that, the mask is set to 64 bit in the ixgebvf driver probe[1] > > Aha, but of course it's still the same struct device getting bound to > VFIO later, so whatever mask the first driver set is still in there when > we go through of_dma_configure() the second time (and the fact that we > go through more than once being the new behaviour). So yes, this is a > legitimate problem and we really do need to be robust against size > overflow. I reckon the below tweak of your fix is probably the way to > go; cleaning up the arch_setup_dma_ops() interface can happen later. > ok, i will add this fix separately and also the acpi fix that lorenzo has suggested in patch #8 in to the series after testing confirmation. Regards, Sricharan > > -----8<----- > diff --git a/drivers/of/device.c b/drivers/of/device.c > index 9933077df7b7..77d080bde52d 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -107,7 +107,7 @@ void of_dma_configure(struct device *dev, struct > device_node *np) > ret = of_dma_get_range(np, &dma_addr, &paddr, &size); > if (ret < 0) { > dma_addr = offset = 0; > - size = dev->coherent_dma_mask + 1; > + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > } else { > offset = PFN_DOWN(paddr - dma_addr); >