Thanks Bjorn for replying on this thread. On Wed, May 13, 2020 at 3:33 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > [+cc linux-pci] > > On Mon, May 11, 2020 at 07:46:06PM -0700, Prabhakar Kushwaha wrote: > > An SMMU Stream table is created by the primary kernel. This table is > > used by the SMMU to perform address translations for device-originated > > transactions. Any crash (if happened) launches the kdump kernel which > > re-creates the SMMU Stream table. New transactions will be translated > > via this new table.. > > > > There are scenarios, where devices are still having old pending > > transactions (configured in the primary kernel). These transactions > > come in-between Stream table creation and device-driver probe. > > As new stream table does not have entry for older transactions, > > it will be aborted by SMMU. > > > > Similar observations were found with PCIe-Intel 82576 Gigabit > > Network card. It sends old Memory Read transaction in kdump kernel. > > Transactions configured for older Stream table entries, that do not > > exist any longer in the new table, will cause a PCIe Completion Abort. > > That sounds like exactly what we want, doesn't it? > > Or do you *want* DMA from the previous kernel to complete? That will > read or scribble on something, but maybe that's not terrible as long > as it's not memory used by the kdump kernel. > Yes, Abort should happen. But it should happen in context of driver. But current abort is happening because of SMMU and no driver/pcie setup present at this moment. Solution of this issue should be at 2 place a) SMMU level: I still believe, this patch has potential to overcome issue till finally driver's probe takeover. b) Device level: Even if something goes wrong. Driver/device should able to recover. > > Returned PCIe completion abort further leads to AER Errors from APEI > > Generic Hardware Error Source (GHES) with completion timeout. > > A network device hang is observed even after continuous > > reset/recovery from driver, Hence device is no more usable. > > The fact that the device is no longer usable is definitely a problem. > But in principle we *should* be able to recover from these errors. If > we could recover and reliably use the device after the error, that > seems like it would be a more robust solution that having to add > special cases in every IOMMU driver. > > If you have details about this sort of error, I'd like to try to fix > it because we want to recover from that sort of error in normal > (non-crash) situations as well. > Completion abort case should be gracefully handled. And device should always remain usable. There are 2 scenario which I am testing with Ethernet card PCIe-Intel 82576 Gigabit Network card. I) Crash testing using kdump root file system: De-facto scenario - kdump file system does not have Ethernet driver - A lot of AER prints [1], making it impossible to work on shell of kdump root file system. - Note kdump shell allows to use makedumpfile, vmcore-dmesg applications. II) Crash testing using default root file system: Specific case to test Ethernet driver in second kernel - Default root file system have Ethernet driver - AER error comes even before the driver probe starts. - Driver does reset Ethernet card as part of probe but no success. - AER also tries to recover. but no success. [2] - I also tries to remove AER errors by using "pci=noaer" bootargs and commenting ghes_handle_aer() from GHES driver.. than different set of errors come which also never able to recover [3] As per my understanding, possible solutions are - Copy SMMU table i.e. this patch OR - Doing pci_reset_function() during enumeration phase. I also tried clearing "M" bit using pci_clear_master during enumeration but it did not help. Because driver re-set M bit causing same AER error again. -pk --------------------------------------------------------------------------------------------------------------------------- [1] with bootargs having pci=noaer [ 22.494648] {4}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1 [ 22.512773] {4}[Hardware Error]: event severity: recoverable [ 22.518419] {4}[Hardware Error]: Error 0, type: recoverable [ 22.544804] {4}[Hardware Error]: section_type: PCIe error [ 22.550363] {4}[Hardware Error]: port_type: 0, PCIe end point [ 22.556268] {4}[Hardware Error]: version: 3.0 [ 22.560785] {4}[Hardware Error]: command: 0x0507, status: 0x4010 [ 22.576852] {4}[Hardware Error]: device_id: 0000:09:00.1 [ 22.582323] {4}[Hardware Error]: slot: 0 [ 22.586406] {4}[Hardware Error]: secondary_bus: 0x00 [ 22.591530] {4}[Hardware Error]: vendor_id: 0x8086, device_id: 0x10c9 [ 22.608900] {4}[Hardware Error]: class_code: 000002 [ 22.613938] {4}[Hardware Error]: serial number: 0xff1b4580, 0x90e2baff [ 22.803534] pci 0000:09:00.1: AER: aer_status: 0x00004000, aer_mask: 0x00000000 [ 22.810838] pci 0000:09:00.1: AER: [14] CmpltTO (First) [ 22.817613] pci 0000:09:00.1: AER: aer_layer=Transaction Layer, aer_agent=Requester ID [ 22.847374] pci 0000:09:00.1: AER: aer_uncor_severity: 0x00062011 [ 22.866161] mpt3sas_cm0: 63 BIT PCI BUS DMA ADDRESSING SUPPORTED, total mem (8153768 kB) [ 22.946178] pci 0000:09:00.0: AER: can't recover (no error_detected callback) [ 22.995142] pci 0000:09:00.1: AER: can't recover (no error_detected callback) [ 23.002300] pcieport 0000:00:09.0: AER: device recovery failed [ 23.027607] pci 0000:09:00.1: AER: aer_status: 0x00004000, aer_mask: 0x00000000 [ 23.044109] pci 0000:09:00.1: AER: [14] CmpltTO (First) [ 23.060713] pci 0000:09:00.1: AER: aer_layer=Transaction Layer, aer_agent=Requester ID [ 23.068616] pci 0000:09:00.1: AER: aer_uncor_severity: 0x00062011 [ 23.122056] pci 0000:09:00.0: AER: can't recover (no error_detected callback) ---------------------------------------------------------------------------------------------------------------------------- [2] Normal bootargs. [ 54.252454] {6}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1 [ 54.265827] {6}[Hardware Error]: event severity: recoverable [ 54.271473] {6}[Hardware Error]: Error 0, type: recoverable [ 54.281605] {6}[Hardware Error]: section_type: PCIe error [ 54.287163] {6}[Hardware Error]: port_type: 0, PCIe end point [ 54.296955] {6}[Hardware Error]: version: 3.0 [ 54.301471] {6}[Hardware Error]: command: 0x0507, status: 0x4010 [ 54.312520] {6}[Hardware Error]: device_id: 0000:09:00.1 [ 54.317991] {6}[Hardware Error]: slot: 0 [ 54.322074] {6}[Hardware Error]: secondary_bus: 0x00 [ 54.327197] {6}[Hardware Error]: vendor_id: 0x8086, device_id: 0x10c9 [ 54.333797] {6}[Hardware Error]: class_code: 000002 [ 54.351312] {6}[Hardware Error]: serial number: 0xff1b4580, 0x90e2baff [ 54.358001] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 54.376852] pcieport 0000:00:09.0: AER: device recovery successful [ 54.383034] igb 0000:09:00.1: AER: aer_status: 0x00004000, aer_mask: 0x00000000 [ 54.390348] igb 0000:09:00.1: AER: [14] CmpltTO (First) [ 54.397144] igb 0000:09:00.1: AER: aer_layer=Transaction Layer, aer_agent=Requester ID [ 54.409555] igb 0000:09:00.1: AER: aer_uncor_severity: 0x00062011 [ 54.551370] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 54.705214] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 54.758703] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 54.865445] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 54.888751] pcieport 0000:00:09.0: AER: device recovery successful [ 54.894933] igb 0000:09:00.1: AER: aer_status: 0x00004000, aer_mask: 0x00000000 [ 54.902228] igb 0000:09:00.1: AER: [14] CmpltTO (First) [ 54.916059] igb 0000:09:00.1: AER: aer_layer=Transaction Layer, aer_agent=Requester ID [ 54.923972] igb 0000:09:00.1: AER: aer_uncor_severity: 0x00062011 [ 55.057272] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 274.571401] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 274.686138] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 274.786134] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 274.886141] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 397.792897] Workqueue: events aer_recover_work_func [ 397.797760] Call trace: [ 397.800199] __switch_to+0xcc/0x108 [ 397.803675] __schedule+0x2c0/0x700 [ 397.807150] schedule+0x58/0xe8 [ 397.810283] schedule_preempt_disabled+0x18/0x28 [ 397.810788] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 397.814887] __mutex_lock.isra.9+0x288/0x5c8 [ 397.814890] __mutex_lock_slowpath+0x1c/0x28 [ 397.830962] mutex_lock+0x4c/0x68 [ 397.834264] report_slot_reset+0x30/0xa0 [ 397.838178] pci_walk_bus+0x68/0xc0 [ 397.841653] pcie_do_recovery+0xe8/0x248 [ 397.845562] aer_recover_work_func+0x100/0x138 [ 397.849995] process_one_work+0x1bc/0x458 [ 397.853991] worker_thread+0x150/0x500 [ 397.857727] kthread+0x114/0x118 [ 397.860945] ret_from_fork+0x10/0x18 [ 397.864525] INFO: task kworker/223:2:2939 blocked for more than 122 seconds. [ 397.871564] Not tainted 5.7.0-rc3+ #68 [ 397.875819] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 397.883638] kworker/223:2 D 0 2939 2 0x00000228 [ 397.889121] Workqueue: ipv6_addrconf addrconf_verify_work [ 397.894505] Call trace: [ 397.896940] __switch_to+0xcc/0x108 [ 397.900419] __schedule+0x2c0/0x700 [ 397.903894] schedule+0x58/0xe8 [ 397.907023] schedule_preempt_disabled+0x18/0x28 [ 397.910798] AER: AER recover: Buffer overflow when recovering AER for 0000:09:00:1 [ 397.911630] __mutex_lock.isra.9+0x288/0x5c8 [ 397.923440] __mutex_lock_slowpath+0x1c/0x28 [ 397.927696] mutex_lock+0x4c/0x68 [ 397.931005] rtnl_lock+0x24/0x30 [ 397.934220] addrconf_verify_work+0x18/0x30 [ 397.938394] process_one_work+0x1bc/0x458 [ 397.942390] worker_thread+0x150/0x500 [ 397.946126] kthread+0x114/0x118 [ 397.949345] ret_from_fork+0x10/0x18 --------------------------------------------------------------------------------------------------------------------------------- [3] with bootargs as pci=noaer and comment ghes_halder_aer() from AER driver [ 69.037035] igb 0000:09:00.1 enp9s0f1: Reset adapter [ 69.348446] {9}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 [ 69.356698] {9}[Hardware Error]: It has been corrected by h/w and requires no further action [ 69.365121] {9}[Hardware Error]: event severity: corrected [ 69.370593] {9}[Hardware Error]: Error 0, type: corrected [ 69.376064] {9}[Hardware Error]: section_type: PCIe error [ 69.381623] {9}[Hardware Error]: port_type: 4, root port [ 69.387094] {9}[Hardware Error]: version: 3.0 [ 69.391611] {9}[Hardware Error]: command: 0x0106, status: 0x4010 [ 69.397777] {9}[Hardware Error]: device_id: 0000:00:09.0 [ 69.403248] {9}[Hardware Error]: slot: 0 [ 69.407331] {9}[Hardware Error]: secondary_bus: 0x09 [ 69.412455] {9}[Hardware Error]: vendor_id: 0x177d, device_id: 0xaf84 [ 69.419055] {9}[Hardware Error]: class_code: 000406 [ 69.424093] {9}[Hardware Error]: bridge: secondary_status: 0x6000, control: 0x0002 [ 72.118132] igb 0000:09:00.1 enp9s0f1: igb: enp9s0f1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX [ 73.995068] igb 0000:09:00.1: Detected Tx Unit Hang [ 73.995068] Tx Queue <2> [ 73.995068] TDH <0> [ 73.995068] TDT <1> [ 73.995068] next_to_use <1> [ 73.995068] next_to_clean <0> [ 73.995068] buffer_info[next_to_clean] [ 73.995068] time_stamp <ffff9c1a> [ 73.995068] next_to_watch <0000000097d42934> [ 73.995068] jiffies <ffff9cd0> [ 73.995068] desc.status <168000> [ 75.987323] igb 0000:09:00.1: Detected Tx Unit Hang [ 75.987323] Tx Queue <2> [ 75.987323] TDH <0> [ 75.987323] TDT <1> [ 75.987323] next_to_use <1> [ 75.987323] next_to_clean <0> [ 75.987323] buffer_info[next_to_clean] [ 75.987323] time_stamp <ffff9c1a> [ 75.987323] next_to_watch <0000000097d42934> [ 75.987323] jiffies <ffff9d98> [ 75.987323] desc.status <168000> [ 77.952661] {10}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1 [ 77.971790] {10}[Hardware Error]: event severity: recoverable [ 77.977522] {10}[Hardware Error]: Error 0, type: recoverable [ 77.983254] {10}[Hardware Error]: section_type: PCIe error [ 77.999930] {10}[Hardware Error]: port_type: 0, PCIe end point [ 78.005922] {10}[Hardware Error]: version: 3.0 [ 78.010526] {10}[Hardware Error]: command: 0x0507, status: 0x4010 [ 78.016779] {10}[Hardware Error]: device_id: 0000:09:00.1 [ 78.033107] {10}[Hardware Error]: slot: 0 [ 78.037276] {10}[Hardware Error]: secondary_bus: 0x00 [ 78.066253] {10}[Hardware Error]: vendor_id: 0x8086, device_id: 0x10c9 [ 78.072940] {10}[Hardware Error]: class_code: 000002 [ 78.078064] {10}[Hardware Error]: serial number: 0xff1b4580, 0x90e2baff [ 78.096202] igb 0000:09:00.1: Detected Tx Unit Hang [ 78.096202] Tx Queue <2> [ 78.096202] TDH <0> [ 78.096202] TDT <1> [ 78.096202] next_to_use <1> [ 78.096202] next_to_clean <0> [ 78.096202] buffer_info[next_to_clean] [ 78.096202] time_stamp <ffff9c1a> [ 78.096202] next_to_watch <0000000097d42934> [ 78.096202] jiffies <ffff9e6a> [ 78.096202] desc.status <168000> [ 79.587406] {11}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 [ 79.595744] {11}[Hardware Error]: It has been corrected by h/w and requires no further action [ 79.604254] {11}[Hardware Error]: event severity: corrected [ 79.609813] {11}[Hardware Error]: Error 0, type: corrected [ 79.615371] {11}[Hardware Error]: section_type: PCIe error [ 79.621016] {11}[Hardware Error]: port_type: 4, root port [ 79.626574] {11}[Hardware Error]: version: 3.0 [ 79.631177] {11}[Hardware Error]: command: 0x0106, status: 0x4010 [ 79.637430] {11}[Hardware Error]: device_id: 0000:00:09.0 [ 79.642988] {11}[Hardware Error]: slot: 0 [ 79.647157] {11}[Hardware Error]: secondary_bus: 0x09 [ 79.652368] {11}[Hardware Error]: vendor_id: 0x177d, device_id: 0xaf84 [ 79.659055] {11}[Hardware Error]: class_code: 000406 [ 79.664180] {11}[Hardware Error]: bridge: secondary_status: 0x6000, control: 0x0002 [ 79.987052] igb 0000:09:00.1: Detected Tx Unit Hang [ 79.987052] Tx Queue <2> [ 79.987052] TDH <0> [ 79.987052] TDT <1> [ 79.987052] next_to_use <1> [ 79.987052] next_to_clean <0> [ 79.987052] buffer_info[next_to_clean] [ 79.987052] time_stamp <ffff9c1a> [ 79.987052] next_to_watch <0000000097d42934> [ 79.987052] jiffies <ffff9f28> [ 79.987052] desc.status <168000> [ 79.987056] igb 0000:09:00.1: Detected Tx Unit Hang [ 79.987056] Tx Queue <3> [ 79.987056] TDH <0> [ 79.987056] TDT <1> [ 79.987056] next_to_use <1> [ 79.987056] next_to_clean <0> [ 79.987056] buffer_info[next_to_clean] [ 79.987056] time_stamp <ffff9e43> [ 79.987056] next_to_watch <000000008da33deb> [ 79.987056] jiffies <ffff9f28> [ 79.987056] desc.status <514000> [ 81.986688] igb 0000:09:00.1 enp9s0f1: Reset adapter [ 81.986842] igb 0000:09:00.1: Detected Tx Unit Hang [ 81.986842] Tx Queue <2> [ 81.986842] TDH <0> [ 81.986842] TDT <1> [ 81.986842] next_to_use <1> [ 81.986842] next_to_clean <0> [ 81.986842] buffer_info[next_to_clean] [ 81.986842] time_stamp <ffff9c1a> [ 81.986842] next_to_watch <0000000097d42934> [ 81.986842] jiffies <ffff9ff0> [ 81.986842] desc.status <168000> [ 81.986844] igb 0000:09:00.1: Detected Tx Unit Hang [ 81.986844] Tx Queue <3> [ 81.986844] TDH <0> [ 81.986844] TDT <1> [ 81.986844] next_to_use <1> [ 81.986844] next_to_clean <0> [ 81.986844] buffer_info[next_to_clean] [ 81.986844] time_stamp <ffff9e43> [ 81.986844] next_to_watch <000000008da33deb> [ 81.986844] jiffies <ffff9ff0> [ 81.986844] desc.status <514000> [ 85.346515] {12}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0 [ 85.354854] {12}[Hardware Error]: It has been corrected by h/w and requires no further action [ 85.363365] {12}[Hardware Error]: event severity: corrected [ 85.368924] {12}[Hardware Error]: Error 0, type: corrected [ 85.374483] {12}[Hardware Error]: section_type: PCIe error [ 85.380129] {12}[Hardware Error]: port_type: 0, PCIe end point [ 85.386121] {12}[Hardware Error]: version: 3.0 [ 85.390725] {12}[Hardware Error]: command: 0x0507, status: 0x0010 [ 85.396980] {12}[Hardware Error]: device_id: 0000:09:00.0 [ 85.402540] {12}[Hardware Error]: slot: 0 [ 85.406710] {12}[Hardware Error]: secondary_bus: 0x00 [ 85.411921] {12}[Hardware Error]: vendor_id: 0x8086, device_id: 0x10c9 [ 85.418609] {12}[Hardware Error]: class_code: 000002 [ 85.423733] {12}[Hardware Error]: serial number: 0xff1b4580, 0x90e2baff [ 85.826695] igb 0000:09:00.1 enp9s0f1: igb: enp9s0f1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX > > So, If we are in a kdump kernel try to copy SMMU Stream table from > > primary/old kernel to preserve the mappings until the device driver > > takes over. > > > > Signed-off-by: Prabhakar Kushwaha <pkushwaha@xxxxxxxxxxx> > > --- > > Changes for v2: Used memremap in-place of ioremap > > > > V2 patch has been sanity tested. > > > > V1 patch has been tested with > > A) PCIe-Intel 82576 Gigabit Network card in following > > configurations with "no AER error". Each iteration has > > been tested on both Suse kdump rfs And default Centos distro rfs. > > > > 1) with 2 level stream table > > ---------------------------------------------------- > > SMMU | Normal Ping | Flood Ping > > ----------------------------------------------------- > > Default Operation | 100 times | 10 times > > ----------------------------------------------------- > > IOMMU bypass | 41 times | 10 times > > ----------------------------------------------------- > > > > 2) with Linear stream table. > > ----------------------------------------------------- > > SMMU | Normal Ping | Flood Ping > > ------------------------------------------------------ > > Default Operation | 100 times | 10 times > > ------------------------------------------------------ > > IOMMU bypass | 55 times | 10 times > > ------------------------------------------------------- > > > > B) This patch is also tested with Micron Technology Inc 9200 PRO NVMe > > SSD card with 2 level stream table using "fio" in mixed read/write and > > only read configurations. It is tested for both Default Operation and > > IOMMU bypass mode for minimum 10 iterations across Centos kdump rfs and > > default Centos ditstro rfs. > > > > This patch is not full proof solution. Issue can still come > > from the point device is discovered and driver probe called. > > This patch has reduced window of scenario from "SMMU Stream table > > creation - device-driver" to "device discovery - device-driver". > > Usually, device discovery to device-driver is very small time. So > > the probability is very low. > > > > Note: device-discovery will overwrite existing stream table entries > > with both SMMU stage as by-pass. > > > > > > drivers/iommu/arm-smmu-v3.c | 36 +++++++++++++++++++++++++++++++++++- > > 1 file changed, 35 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > > index 82508730feb7..d492d92c2dd7 100644 > > --- a/drivers/iommu/arm-smmu-v3.c > > +++ b/drivers/iommu/arm-smmu-v3.c > > @@ -1847,7 +1847,13 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, > > break; > > case STRTAB_STE_0_CFG_S1_TRANS: > > case STRTAB_STE_0_CFG_S2_TRANS: > > - ste_live = true; > > + /* > > + * As kdump kernel copy STE table from previous > > + * kernel. It still may have valid stream table entries. > > + * Forcing entry as false to allow overwrite. > > + */ > > + if (!is_kdump_kernel()) > > + ste_live = true; > > break; > > case STRTAB_STE_0_CFG_ABORT: > > BUG_ON(!disable_bypass); > > @@ -3264,6 +3270,9 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) > > return -ENOMEM; > > } > > > > + if (is_kdump_kernel()) > > + return 0; > > + > > for (i = 0; i < cfg->num_l1_ents; ++i) { > > arm_smmu_write_strtab_l1_desc(strtab, &cfg->l1_desc[i]); > > strtab += STRTAB_L1_DESC_DWORDS << 3; > > @@ -3272,6 +3281,23 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) > > return 0; > > } > > > > +static void arm_smmu_copy_table(struct arm_smmu_device *smmu, > > + struct arm_smmu_strtab_cfg *cfg, u32 size) > > +{ > > + struct arm_smmu_strtab_cfg rdcfg; > > + > > + rdcfg.strtab_dma = readq_relaxed(smmu->base + ARM_SMMU_STRTAB_BASE); > > + rdcfg.strtab_base_cfg = readq_relaxed(smmu->base > > + + ARM_SMMU_STRTAB_BASE_CFG); > > + > > + rdcfg.strtab_dma &= STRTAB_BASE_ADDR_MASK; > > + rdcfg.strtab = memremap(rdcfg.strtab_dma, size, MEMREMAP_WB); > > + > > + memcpy_fromio(cfg->strtab, rdcfg.strtab, size); > > + > > + cfg->strtab_base_cfg = rdcfg.strtab_base_cfg; > > +} > > + > > static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu) > > { > > void *strtab; > > @@ -3307,6 +3333,9 @@ static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu) > > reg |= FIELD_PREP(STRTAB_BASE_CFG_SPLIT, STRTAB_SPLIT); > > cfg->strtab_base_cfg = reg; > > > > + if (is_kdump_kernel()) > > + arm_smmu_copy_table(smmu, cfg, l1size); > > + > > return arm_smmu_init_l1_strtab(smmu); > > } > > > > @@ -3334,6 +3363,11 @@ static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu) > > reg |= FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE, smmu->sid_bits); > > cfg->strtab_base_cfg = reg; > > > > + if (is_kdump_kernel()) { > > + arm_smmu_copy_table(smmu, cfg, size); > > + return 0; > > + } > > + > > arm_smmu_init_bypass_stes(strtab, cfg->num_l1_ents); > > return 0; > > } > > -- > > 2.18.2 > > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec