From: Madalin Bucur Date: Fri, 21 Dec 2018 14:41:42 +0000 (+0200) Subject: soc: fsl: qbman: avoid race in clearing QMan interrupt X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=89857a8a5c89a406b967ab2be7bd2ccdbe75e73d;p=linux.git soc: fsl: qbman: avoid race in clearing QMan interrupt By clearing all interrupt sources, not only those that already occurred, the existing code may acknowledge by mistake interrupts that occurred after the code checks for them. Signed-off-by: Madalin Bucur Signed-off-by: Roy Pledge Signed-off-by: Li Yang --- diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c index 52c153cd795a8..636f83f781f5a 100644 --- a/drivers/soc/fsl/qbman/qman.c +++ b/drivers/soc/fsl/qbman/qman.c @@ -1143,18 +1143,19 @@ static void qm_mr_process_task(struct work_struct *work); static irqreturn_t portal_isr(int irq, void *ptr) { struct qman_portal *p = ptr; - - u32 clear = QM_DQAVAIL_MASK | p->irq_sources; u32 is = qm_in(&p->p, QM_REG_ISR) & p->irq_sources; + u32 clear = 0; if (unlikely(!is)) return IRQ_NONE; /* DQRR-handling if it's interrupt-driven */ - if (is & QM_PIRQ_DQRI) + if (is & QM_PIRQ_DQRI) { __poll_portal_fast(p, QMAN_POLL_LIMIT); + clear = QM_DQAVAIL_MASK | QM_PIRQ_DQRI; + } /* Handling of anything else that's interrupt-driven */ - clear |= __poll_portal_slow(p, is); + clear |= __poll_portal_slow(p, is) & QM_PIRQ_SLOW; qm_out(&p->p, QM_REG_ISR, clear); return IRQ_HANDLED; }