>-----Original Message----- >From: Tomas Henzl [mailto:thenzl@xxxxxxxxxx] >Sent: Tuesday, June 02, 2015 3:20 PM >To: Sumit Saxena; linux-scsi@xxxxxxxxxxxxxxx >Cc: Kashyap Desai >Subject: Re: [PATCH] regression, megaraid - fix irq setup process > >On 06/02/2015 09:06 AM, Sumit Saxena wrote: >>> -----Original Message----- >>> From: Tomas Henzl [mailto:thenzl@xxxxxxxxxx] >>> Sent: Monday, June 01, 2015 10:57 PM >>> To: linux-scsi@xxxxxxxxxxxxxxx >>> Cc: kashyap.desai@xxxxxxxxxxxxx; Sumit.Saxena@xxxxxxxxxxxxx >>> Subject: [PATCH] regression, megaraid - fix irq setup process >>> >>> This fixes a regression caused by commit >>> d3557fc8be11d25f316884581f487684f8e7dad3 >>> megaraid_sas : Add separate function for setting up IRQs This makes >>> boot >> end >>> with 'root does not exist' message on certain adapters. >>> >>> The bug is that the driver does not setup ints for cards without >>> msi-x >> support. >>> This patch fixes it, in addition to that it moves irq-enable call >>> after >> tasklet >>> initialisation - otherwise a kernel panic may occur, when an int >>> arrives >> before >>> the tasklet is ready. >> >> Thanks for pointing it out. >> Tasklet is only scheduled for MFI adapters inside ISR routine and all >> commands fired prior to "tasklet_init" are in polled mode and MFI >> adapters will not send interrupt for the same. >> Fusion adapters may send the interrupts but their ISR function don't >> use tasklet at all so there should not be any problem. >On my card it happens - and kernel panics. > >> We will move tasklet_init prior to enable_intr. Calling enable_intr >> later after firing few more DCMDs will cause more DCMDs to be fired in >> polled mode(though fusion adapter will send interrupt but will not >> free up MFI frame used). >> I agree that cleaning up of this is required. I will send a patch to >> clean it up and address few additional stuff. >This patch fixes a regression caused by your previous patch, a solution is >needed soon. >Please don't forget that this patch fixes also the issue of the driver not >setting >the irq at all for cards without msi-x support and add it to you fix. Tomas, I have sent modified patch in which tasklet_init will be done before enable_intr (instead of calling enable_intr at later point of time). that patch should also fix the issue. Thanks, Sumit > >--tm >> >>> >>> Signed-off-by: Tomas Henzl <thenzl@xxxxxxxxxx> >>> --- >>> drivers/scsi/megaraid/megaraid_sas_base.c | 22 ++++++++++------------ >>> 1 file changed, 10 insertions(+), 12 deletions(-) >>> >>> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c >>> b/drivers/scsi/megaraid/megaraid_sas_base.c >>> index a022c39153..3771d6fff5 100644 >>> --- a/drivers/scsi/megaraid/megaraid_sas_base.c >>> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c >>> @@ -4619,18 +4619,16 @@ static int megasas_init_fw(struct >>> megasas_instance *instance) >>> instance->msix_vectors = i; >>> else >>> instance->msix_vectors = 0; >>> + } >>> >>> - dev_info(&instance->pdev->dev, >>> - "firmware supports msix\t: (%d)", fw_msix_count); >>> - dev_info(&instance->pdev->dev, >>> - "current msix/online cpus\t: (%d/%d)\n", >>> - instance->msix_vectors, (unsigned >>> int)num_online_cpus()); >>> + dev_info(&instance->pdev->dev, "firmware supports msix\t: (%d)", >>> + fw_msix_count); >>> + dev_info(&instance->pdev->dev, "current msix/online cpus\t: >>> (%d/%d)\n", >>> + instance->msix_vectors, (unsigned int)num_online_cpus()); >>> >>> - if (instance->msix_vectors ? >>> - megasas_setup_irqs_msix(instance, 1) : >>> - megasas_setup_irqs_ioapic(instance)) >>> - goto fail_setup_irqs; >>> - } >>> + if (instance->msix_vectors ? megasas_setup_irqs_msix(instance, 1) >> : >>> + megasas_setup_irqs_ioapic(instance)) >>> + goto fail_setup_irqs; >>> >>> instance->ctrl_info = kzalloc(sizeof(struct megasas_ctrl_info), >>> GFP_KERNEL); >>> @@ -4646,8 +4644,6 @@ static int megasas_init_fw(struct >>> megasas_instance >>> *instance) >>> /* Get operational params, sge flags, send init cmd to controller >> */ >>> if (instance->instancet->init_adapter(instance)) >>> goto fail_init_adapter; >>> - instance->instancet->enable_intr(instance); >>> - >>> printk(KERN_ERR "megasas: INIT adapter done\n"); >>> >>> /** for passthrough >>> @@ -4769,6 +4765,8 @@ static int megasas_init_fw(struct >>> megasas_instance >>> *instance) >>> tasklet_init(&instance->isr_tasklet, instance->instancet->tasklet, >>> (unsigned long)instance); >>> >>> + instance->instancet->enable_intr(instance); >>> + >>> /* Launch SR-IOV heartbeat timer */ >>> if (instance->requestorId) { >>> if (!megasas_sriov_start_heartbeat(instance, 1)) >> >>> -- >>> 1.9.3 >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-scsi" >> in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo >> info at http://vger.kernel.org/majordomo-info.html >> -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
