diff options
| author | Martin Aberg <maberg@gaisler.com> | 2017-01-26 11:01:10 +0100 |
|---|---|---|
| committer | Daniel Hellstrom <daniel@gaisler.com> | 2017-05-14 12:31:58 +0200 |
| commit | 057496906f2359433e318abdb644e5026ff08f32 (patch) | |
| tree | a20ba9d026be28d0d131481ddb36f2c9f7abe7d0 | |
| parent | leon, grcan: unregister interrupt handler at close (diff) | |
| download | rtems-057496906f2359433e318abdb644e5026ff08f32.tar.bz2 | |
leon, grcan: fixed race on interrupt mask register
There was a potential read-modify-write race on the interrupt mask (imr)
register between the ISR and user functions.
| -rw-r--r-- | c/src/lib/libbsp/sparc/shared/can/grcan.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/sparc/shared/can/grcan.c b/c/src/lib/libbsp/sparc/shared/can/grcan.c index c7aadaec23..9e1c05da97 100644 --- a/c/src/lib/libbsp/sparc/shared/can/grcan.c +++ b/c/src/lib/libbsp/sparc/shared/can/grcan.c @@ -1712,6 +1712,7 @@ int grcan_set_afilter(void *d, const struct grcan_filter *filter) int grcan_set_sfilter(void *d, const struct grcan_filter *filter) { struct grcan_priv *pDev = d; + SPIN_IRQFLAGS(oldLevel); FUNCDBG(); @@ -1721,13 +1722,17 @@ int grcan_set_sfilter(void *d, const struct grcan_filter *filter) pDev->sfilter.mask = 0; /* disable Sync interrupt */ + SPIN_LOCK_IRQ(&pDev->devlock, oldLevel); pDev->regs->imr = READ_REG(&pDev->regs->imr) & ~(GRCAN_RXSYNC_IRQ|GRCAN_TXSYNC_IRQ); + SPIN_UNLOCK_IRQ(&pDev->devlock, oldLevel); }else{ /* Save filter */ pDev->sfilter = *filter; /* Enable Sync interrupt */ + SPIN_LOCK_IRQ(&pDev->devlock, oldLevel); pDev->regs->imr = READ_REG(&pDev->regs->imr) | (GRCAN_RXSYNC_IRQ|GRCAN_TXSYNC_IRQ); + SPIN_UNLOCK_IRQ(&pDev->devlock, oldLevel); } /* Set Sync RX/TX filter */ grcan_hw_sync(pDev->regs,&pDev->sfilter); @@ -1756,6 +1761,7 @@ static void grcan_interrupt(void *arg) struct grcan_priv *pDev = arg; unsigned int status = READ_REG(&pDev->regs->pimsr); unsigned int canstat = READ_REG(&pDev->regs->stat); + SPIN_ISR_IRQFLAGS(irqflags); /* Spurious IRQ call? */ if ( !status && !canstat ) @@ -1777,8 +1783,10 @@ static void grcan_interrupt(void *arg) * that is blocked in read/write calls and stop futher calls * to read/write until user has called ioctl(fd,START,0). */ + SPIN_LOCK(&pDev->devlock, irqflags); pDev->started = 0; grcan_hw_stop(pDev); /* this mask all IRQ sources */ + SPIN_UNLOCK(&pDev->devlock, irqflags); status=0x1ffff; /* clear all interrupts */ goto out; } @@ -1803,13 +1811,17 @@ static void grcan_interrupt(void *arg) if ( status & GRCAN_RXIRQ_IRQ ){ /* RX IRQ pointer interrupt */ /*printk("RxIrq 0x%x\n",status);*/ + SPIN_LOCK(&pDev->devlock, irqflags); pDev->regs->imr = READ_REG(&pDev->regs->imr) & ~GRCAN_RXIRQ_IRQ; + SPIN_UNLOCK(&pDev->devlock, irqflags); rtems_semaphore_release(pDev->rx_sem); } if ( status & GRCAN_TXIRQ_IRQ ){ /* TX IRQ pointer interrupt */ + SPIN_LOCK(&pDev->devlock, irqflags); pDev->regs->imr = READ_REG(&pDev->regs->imr) & ~GRCAN_TXIRQ_IRQ; + SPIN_UNLOCK(&pDev->devlock, irqflags); rtems_semaphore_release(pDev->tx_sem); } @@ -1824,7 +1836,9 @@ static void grcan_interrupt(void *arg) } if ( status & GRCAN_TXEMPTY_IRQ ){ + SPIN_LOCK(&pDev->devlock, irqflags); pDev->regs->imr = READ_REG(&pDev->regs->imr) & ~GRCAN_TXEMPTY_IRQ; + SPIN_UNLOCK(&pDev->devlock, irqflags); rtems_semaphore_release(pDev->txempty_sem); } |