From: Wayne Boyer Date: Tue, 17 May 2011 16:18:53 +0000 (-0700) Subject: [SCSI] ipr: fix possible false positive detection of stuck interrupt X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=a5442ba4a428081ebac7090f46c62ffaa17ca951;p=deliverable%2Flinux.git [SCSI] ipr: fix possible false positive detection of stuck interrupt If the driver is getting flooded with interrupts, there's a possibility that the interrupt service routine could falsely detect a stuck interrupt condition and reset the adapter. This patch changes the logic such that the routine will loop back into the command processing code one more time after detecting the stuck interrupt signature. If there are no commands to process after that pass, and the interrupt is still not cleared, then the driver will print the "Error clearing HRRQ" message and reset the adapter. Signed-off-by: Wayne Boyer Acked-by: Brian King Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index 12868ca46110..888086c4e709 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -5149,21 +5149,21 @@ static irqreturn_t ipr_isr(int irq, void *devp) if (ipr_cmd != NULL) { /* Clear the PCI interrupt */ + num_hrrq = 0; do { writel(IPR_PCII_HRRQ_UPDATED, ioa_cfg->regs.clr_interrupt_reg32); int_reg = readl(ioa_cfg->regs.sense_interrupt_reg32); } while (int_reg & IPR_PCII_HRRQ_UPDATED && num_hrrq++ < IPR_MAX_HRRQ_RETRIES); - if (int_reg & IPR_PCII_HRRQ_UPDATED) { - ipr_isr_eh(ioa_cfg, "Error clearing HRRQ"); - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - return IRQ_HANDLED; - } - } else if (rc == IRQ_NONE && irq_none == 0) { int_reg = readl(ioa_cfg->regs.sense_interrupt_reg32); irq_none++; + } else if (num_hrrq == IPR_MAX_HRRQ_RETRIES && + int_reg & IPR_PCII_HRRQ_UPDATED) { + ipr_isr_eh(ioa_cfg, "Error clearing HRRQ"); + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + return IRQ_HANDLED; } else break; }