Hi Greg, Here is the summary of this patch. After host reset, the driver breaks from the device scan loop only when ioc_status of config page request equals MPI2_IOCSTATUS_CONFIG_INVALID_PAGE. If the firmware returns some other ioc_status such as MPI2_IOCSTATUS_INVALID_FUNCTION then this results to infinite loop. As this issue is critical since the driver may go in to infinite loop, so we thought to add this patch in stable kernel also. Regards, Sreekanth >-----Original Message----- >From: gregkh@xxxxxxxxxxxxxxxxxxx [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] >Sent: Tuesday, July 23, 2013 9:27 AM >To: Reddy, Sreekanth; JBottomley@xxxxxxxxxxxxx >Cc: stable@xxxxxxxxxxxxxxx >Subject: WTF: patch "[PATCH] [SCSI] mpt2sas: Fix for device scan following >host reset" was seriously submitted to be applied to the 3.10-stable tree? > >The patch below was submitted to be applied to the 3.10-stable tree. > >I fail to see how this patch meets the stable kernel rules as found at >Documentation/stable_kernel_rules.txt. > >I could be totally wrong, and if so, please respond to ><stable@xxxxxxxxxxxxxxx> and let me know why this patch should be applied. >Otherwise, it is now dropped from my patch queues, never to be seen again. > >thanks, > >greg k-h > >------------------ original commit in Linus's tree ------------------ > >From 6241f22ca12a26ee149cbe31b27bac97dbdc8bc4 Mon Sep 17 00:00:00 >2001 >From: Sreekanth Reddy <Sreekanth.Reddy@xxxxxxx> >Date: Sat, 2 Feb 2013 00:56:18 +0530 >Subject: [PATCH] [SCSI] mpt2sas: Fix for device scan following host reset >could get stuck in a infinite loop > >Modified device scan routine so each configuration page read breaks from the >while loop when the ioc_status is not equal to MPI2_IOCSTATUS_SUCCESS. > >[jejb: checkpatch fixes] >Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@xxxxxxx> >Cc: stable@xxxxxxxxxxxxxxx >Signed-off-by: James Bottomley <JBottomley@xxxxxxxxxxxxx> > >diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c >b/drivers/scsi/mpt2sas/mpt2sas_scsih.c >index 116e201..01dfbab 100644 >--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c >+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c >@@ -7097,12 +7097,15 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > struct _sas_device *sas_device; > struct _sas_node *expander_device; > static struct _raid_device *raid_device; >+ u8 retry_count; > unsigned long flags; > > printk(MPT2SAS_INFO_FMT "scan devices: start\n", ioc->name); > > _scsih_sas_host_refresh(ioc); > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: expanders start\n", >+ ioc->name); > /* expanders */ > handle = 0xFFFF; > while (!(mpt2sas_config_get_expander_pg0(ioc, &mpi_reply, >&expander_pg0, @@ -7111,6 +7114,13 @@ >_scsih_scan_for_devices_after_reset(struct MPT2SAS_ADAPTER *ioc) > MPI2_IOCSTATUS_MASK; > if (ioc_status == MPI2_IOCSTATUS_CONFIG_INVALID_PAGE) > break; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from expander >scan: " >+ "ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > handle = le16_to_cpu(expander_pg0.DevHandle); > spin_lock_irqsave(&ioc->sas_node_lock, flags); > expander_device = >mpt2sas_scsih_expander_find_by_sas_address( >@@ -7119,13 +7129,26 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > if (expander_device) > _scsih_refresh_expander_links(ioc, expander_device, > handle); >- else >+ else { >+ printk(MPT2SAS_INFO_FMT "\tBEFORE adding >expander: " >+ "handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(expander_pg0.SASAddress)); > _scsih_expander_add(ioc, handle); >+ printk(MPT2SAS_INFO_FMT "\tAFTER adding >expander: " >+ "handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(expander_pg0.SASAddress)); >+ } > } > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: expanders complete\n", >+ ioc->name); >+ > if (!ioc->ir_firmware) > goto skip_to_sas; > >+ printk(MPT2SAS_INFO_FMT "\tscan devices phys disk start\n", >+ioc->name); > /* phys disk */ > phys_disk_num = 0xFF; > while (!(mpt2sas_config_get_phys_disk_pg0(ioc, &mpi_reply, @@ - >7135,6 +7158,13 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > MPI2_IOCSTATUS_MASK; > if (ioc_status == MPI2_IOCSTATUS_CONFIG_INVALID_PAGE) > break; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from phys disk >scan:" >+ "ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > phys_disk_num = pd_pg0.PhysDiskNum; > handle = le16_to_cpu(pd_pg0.DevHandle); > spin_lock_irqsave(&ioc->sas_device_lock, flags); @@ -7146,17 >+7176,46 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > &sas_device_pg0, >MPI2_SAS_DEVICE_PGAD_FORM_HANDLE, > handle) != 0) > continue; >+ ioc_status = le16_to_cpu(mpi_reply.IOCStatus) & >+ MPI2_IOCSTATUS_MASK; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from phys disk >scan " >+ "ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > parent_handle = >le16_to_cpu(sas_device_pg0.ParentDevHandle); > if (!_scsih_get_sas_address(ioc, parent_handle, > &sas_address)) { >+ printk(MPT2SAS_INFO_FMT "\tBEFORE adding phys >disk: " >+ " handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(sas_device_pg0.SASAddress)); > mpt2sas_transport_update_links(ioc, sas_address, > handle, sas_device_pg0.PhyNum, > MPI2_SAS_NEG_LINK_RATE_1_5); > set_bit(handle, ioc->pd_handles); >- _scsih_add_device(ioc, handle, 0, 1); >+ retry_count = 0; >+ /* This will retry adding the end device. >+ * _scsih_add_device() will decide on retries and >+ * return "1" when it should be retried >+ */ >+ while (_scsih_add_device(ioc, handle, retry_count++, >+ 1)) { >+ ssleep(1); >+ } >+ printk(MPT2SAS_INFO_FMT "\tAFTER adding phys >disk: " >+ " handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(sas_device_pg0.SASAddress)); > } > } > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: phys disk complete\n", >+ ioc->name); >+ >+ printk(MPT2SAS_INFO_FMT "\tscan devices: volumes start\n", ioc- >>name); > /* volumes */ > handle = 0xFFFF; > while (!(mpt2sas_config_get_raid_volume_pg1(ioc, &mpi_reply, @@ >-7165,6 +7224,13 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > MPI2_IOCSTATUS_MASK; > if (ioc_status == MPI2_IOCSTATUS_CONFIG_INVALID_PAGE) > break; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from volume >scan: " >+ "ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > handle = le16_to_cpu(volume_pg1.DevHandle); > spin_lock_irqsave(&ioc->raid_device_lock, flags); > raid_device = _scsih_raid_device_find_by_wwid(ioc, >@@ -7176,18 +7242,38 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > &volume_pg0, >MPI2_RAID_VOLUME_PGAD_FORM_HANDLE, handle, > sizeof(Mpi2RaidVolPage0_t))) > continue; >+ ioc_status = le16_to_cpu(mpi_reply.IOCStatus) & >+ MPI2_IOCSTATUS_MASK; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from volume >scan: " >+ "ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > if (volume_pg0.VolumeState == >MPI2_RAID_VOL_STATE_OPTIMAL || > volume_pg0.VolumeState == >MPI2_RAID_VOL_STATE_ONLINE || > volume_pg0.VolumeState == >MPI2_RAID_VOL_STATE_DEGRADED) { > memset(&element, 0, >sizeof(Mpi2EventIrConfigElement_t)); > element.ReasonCode = >MPI2_EVENT_IR_CHANGE_RC_ADDED; > element.VolDevHandle = volume_pg1.DevHandle; >+ printk(MPT2SAS_INFO_FMT "\tBEFORE adding >volume: " >+ " handle (0x%04x)\n", ioc->name, >+ volume_pg1.DevHandle); > _scsih_sas_volume_add(ioc, &element); >+ printk(MPT2SAS_INFO_FMT "\tAFTER adding volume: >" >+ " handle (0x%04x)\n", ioc->name, >+ volume_pg1.DevHandle); > } > } > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: volumes complete\n", >+ ioc->name); >+ > skip_to_sas: > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: end devices start\n", >+ ioc->name); > /* sas devices */ > handle = 0xFFFF; > while (!(mpt2sas_config_get_sas_device_pg0(ioc, &mpi_reply, @@ - >7197,6 +7283,13 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > MPI2_IOCSTATUS_MASK; > if (ioc_status == MPI2_IOCSTATUS_CONFIG_INVALID_PAGE) > break; >+ if (ioc_status != MPI2_IOCSTATUS_SUCCESS) { >+ printk(MPT2SAS_INFO_FMT "\tbreak from end device >scan:" >+ " ioc_status(0x%04x), loginfo(0x%08x)\n", >+ ioc->name, ioc_status, >+ le32_to_cpu(mpi_reply.IOCLogInfo)); >+ break; >+ } > handle = le16_to_cpu(sas_device_pg0.DevHandle); > if (!(_scsih_is_end_device( > le32_to_cpu(sas_device_pg0.DeviceInfo)))) >@@ -7209,12 +7302,31 @@ _scsih_scan_for_devices_after_reset(struct >MPT2SAS_ADAPTER *ioc) > continue; > parent_handle = >le16_to_cpu(sas_device_pg0.ParentDevHandle); > if (!_scsih_get_sas_address(ioc, parent_handle, >&sas_address)) { >+ printk(MPT2SAS_INFO_FMT "\tBEFORE adding end >device: " >+ "handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(sas_device_pg0.SASAddress)); > mpt2sas_transport_update_links(ioc, sas_address, >handle, > sas_device_pg0.PhyNum, >MPI2_SAS_NEG_LINK_RATE_1_5); >- _scsih_add_device(ioc, handle, 0, 0); >+ retry_count = 0; >+ /* This will retry adding the end device. >+ * _scsih_add_device() will decide on retries and >+ * return "1" when it should be retried >+ */ >+ while (_scsih_add_device(ioc, handle, retry_count++, >+ 0)) { >+ ssleep(1); >+ } >+ printk(MPT2SAS_INFO_FMT "\tAFTER adding end >device: " >+ "handle (0x%04x), sas_addr(0x%016llx)\n", >+ ioc->name, handle, (unsigned long long) >+ le64_to_cpu(sas_device_pg0.SASAddress)); > } > } > >+ printk(MPT2SAS_INFO_FMT "\tscan devices: end devices >complete\n", >+ ioc->name); >+ > printk(MPT2SAS_INFO_FMT "scan devices: complete\n", ioc->name); >} > >@@ -8076,8 +8188,8 @@ _scsih_probe(struct pci_dev *pdev, const struct >pci_device_id *id) > if (max_sectors != 0xFFFF) { > if (max_sectors < 64) { > shost->max_sectors = 64; >- printk(MPT2SAS_WARN_FMT "Invalid value %d >passed "\ >- "for max_sectors, range is 64 to 32767. Assigning "\ >+ printk(MPT2SAS_WARN_FMT "Invalid value %d >passed " >+ "for max_sectors, range is 64 to 32767. Assigning " > "value of 64.\n", ioc->name, max_sectors); > } else if (max_sectors > 32767) { > shost->max_sectors = 32767; > -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html