Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
[ sorry, for the record I'm not trimming Val's comments - mine are much below] On Wed, Jun 21, 2006 at 05:43:40PM -0700, Valerie Henson wrote: ... Hi folks, The quick summary of my thoughts on this patch is that it isn't the ideal patch, but it works and it's well-tested. Doing my preferred fix (adding a shutdown flag) would be invasive and take many weeks to reach the level of stability of Grant's patch. So I'm taking this patch but adding a comment describing my preferred fix. Here's the long version. The obvious ordering of bringing up the card is: request_irq() setup DMA resources enable interrupts start DMA engine The problem here is request_irq() enables interrupts. SO the third step happens as part of the first step. And if an IRQ happens to be pending, it will blow up. But since we reset the chip at init time, that should never happen. And the obvious ordering of shutting it down is: stop DMA engine disable interrupts remove DMA resources free_irq() This attempts to be symetrical with the init sequence and I like that approach where possible. It's not symetrical in practice because the interrupt code restarts DMA. (which is what you've noted below) The problem with the above shutdown order is that we can receive an interrupt in between stopping DMA and disabling interrupts, and the tulip irq handler will reenable DMA == Boom! The solution I prefer is to make the irq handler aware of whether we are shutting down or not, and not reenable DMA in that case. While I believe this will work too, I don't advocate this approach because I don't like to add code to interrupt handlers unless it's the _only_ way to fix a problem. However, it is a non-trivial patch to get right, and I would rather have the bug fixed short-term with the ordering Grant uses: disable interrupts free_irq() stop rxtx remove DMA resources Make sense to everyone? I'll redo the patch with the comment and get Grant's sign-off. Yes. I'm ok with anything similar to what you posted above: Signed-off-by: Grant Grundler [EMAIL PROTECTED] And Val, thanks for accepting the patch and taking the time to explain where you want to go next with the code in this case. I'll be happy to setup remote access to my test environment when you are ready to test that next step. thanks, grant -VAL - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Tue, Jun 13, 2006 at 05:55:31PM -0600, Grant Grundler wrote: On Thu, Jun 08, 2006 at 11:01:20AM -0600, Grant Grundler wrote: Here is a new patch that moves free_irq() into tulip_down(). The resulting code is structured the same as cp_close(). Val, Two details are wrong in version 2 and are fixed in v3 (appended below): o we don't need synchronize_irq() before calling free_irq(). (It should be removed from cp_close() too) Thanks to willy for pointing me at kernel/irq/manage.c. o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. Tested on rx4640 (HP IA64) for several hours. Please apply. Hi folks, The quick summary of my thoughts on this patch is that it isn't the ideal patch, but it works and it's well-tested. Doing my preferred fix (adding a shutdown flag) would be invasive and take many weeks to reach the level of stability of Grant's patch. So I'm taking this patch but adding a comment describing my preferred fix. Here's the long version. The obvious ordering of bringing up the card is: request_irq() setup DMA resources enable interrupts start DMA engine And the obvious ordering of shutting it down is: stop DMA engine disable interrupts remove DMA resources free_irq() The problem with the above shutdown order is that we can receive an interrupt in between stopping DMA and disabling interrupts, and the tulip irq handler will reenable DMA == Boom! The solution I prefer is to make the irq handler aware of whether we are shutting down or not, and not reenable DMA in that case. However, it is a non-trivial patch to get right, and I would rather have the bug fixed short-term with the ordering Grant uses: disable interrupts free_irq() stop rxtx remove DMA resources Make sense to everyone? I'll redo the patch with the comment and get Grant's sign-off. -VAL - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler wrote: On Thu, Jun 15, 2006 at 10:30:17PM +0200, Francois Romieu wrote: Afaik free_irq() on a shared irq does not touch the hardware and irqs are anything but synchronous. If free_irq() is issued before the device is idle and its irq are not acked, it's wrong. Correct. Before calling free_irq(), patch V3 masks interrupts on tulip and guarantees the tulip will not generate new interrupts before that call. Incorrect -- it does not guarantee that tulip will not generate new interrupt events. Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Fri, Jun 16, 2006 at 03:32:56AM -0400, Jeff Garzik wrote: Correct. Before calling free_irq(), patch V3 masks interrupts on tulip and guarantees the tulip will not generate new interrupts before that call. Incorrect -- it does not guarantee that tulip will not generate new interrupt events. Are you saying the following sequence doesn't mask tulip interrupts? /* Disable interrupts by clearing the interrupt mask. */ iowrite32 (0x, ioaddr + CSR7); ioread32 (ioaddr + CSR7); /* flush posted write */ Secondly, since you've ignored the two previous times I've asked, I'll assume you agree tulip driver has to (and does) handle the case of pending, masked interrupts at initialization because firmware might leave it in that state. thanks, grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
[ Jeff, apologies. I hit reply instead of group reply on previous email. I've added everyone back on the cc list.] On Fri, Jun 16, 2006 at 11:30:32AM -0400, Jeff Garzik wrote: ... Are you saying this sequence won't mask interrupts on tulip? /* Disable interrupts by clearing the interrupt mask. */ iowrite32 (0x, ioaddr + CSR7); ioread32 (ioaddr + CSR7); /* flush posted write */ It does not stop the generation of interrupt events. This use of interrupt events is misleading. The CPU does not sees these interrupt events once we mask interrupts. The DMA engine is still running, packets are still being received. The above code sequence does not change that. I agree. And I'm asking why does anyone care? We clean that up after IRQs are stopped from being delivered to the CPU. ... Secondly, since you have ignored the two previous times I've asked, I'll presume you agree that if firmware leaves it in this state (pending, masked interrupts), that the driver has to (and does) handle it. There is no firmware involved here, at any level, after boot. I agree. What about at boot time? The needed task in the driver has been the same since this thread started: (1) stop generating new work [stop DMA engine], and (2) quiesce the hardware. And it must happen in that order. No it doesn't. I've proven it works in the order I've proposed on pretty damn anal HW. Setting the interrupt mask register to zero doesn't stop new work from appearing. I agree. It stops the screaming interrupt problem. The fact that we are in close or down routine means the user already decided they don't care if new packets do or do not arrive. Unless you can point to a real user who is affected by my proposed patch, I ask again patch v3 be accepted. thanks, grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler wrote: [ Jeff, apologies. I hit reply instead of group reply on previous email. I've added everyone back on the cc list.] On Fri, Jun 16, 2006 at 11:30:32AM -0400, Jeff Garzik wrote: ... Are you saying this sequence won't mask interrupts on tulip? /* Disable interrupts by clearing the interrupt mask. */ iowrite32 (0x, ioaddr + CSR7); ioread32 (ioaddr + CSR7); /* flush posted write */ It does not stop the generation of interrupt events. This use of interrupt events is misleading. The CPU does not sees these interrupt events once we mask interrupts. The DMA engine is still running, packets are still being received. The above code sequence does not change that. I agree. And I'm asking why does anyone care? We clean that up after IRQs are stopped from being delivered to the CPU. ... Secondly, since you have ignored the two previous times I've asked, I'll presume you agree that if firmware leaves it in this state (pending, masked interrupts), that the driver has to (and does) handle it. There is no firmware involved here, at any level, after boot. I agree. What about at boot time? We reset the chip each time we do an interface-up. The needed task in the driver has been the same since this thread started: (1) stop generating new work [stop DMA engine], and (2) quiesce the hardware. And it must happen in that order. No it doesn't. I've proven it works in the order I've proposed on pretty damn anal HW. Setting the interrupt mask register to zero doesn't stop new work from appearing. I agree. It stops the screaming interrupt problem. The fact that we are in close or down routine means the user already decided they don't care if new packets do or do not arrive. Unless you can point to a real user who is affected by my proposed patch, I ask again patch v3 be accepted. All users are affected. There is still a race window due to calling free_irq() before stopping the DMA engine, you've simply minimized it. I don't see why it's so difficult to see (a) you are introducing a non-standard ordering, different from other net drivers (b) you are introducing an ordering that is counter to how the hardware is designed (c) if you follow the natural ordering, you are GUARANTEED not to have screaming interrupts, DMA still going across the PCI bus, and dozens of other details. Rather than running through all of these details, and tweaking your patch for each of them (as you have done with V1-V2 and V2-V3), simply _guarantee_ that you will not have problems. Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler [EMAIL PROTECTED] : [shared irq] I thought we've worked through that already: http://www.spinics.net/lists/netdev/msg05902.html Patch v3 takes care of that problem. The first step in the sequence is to mask IRQs on the tulip. The neighbor device sharing the IRQ will not see any interrupts from the tulip after that. Afaik free_irq() on a shared irq does not touch the hardware and irqs are anything but synchronous. If free_irq() is issued before the device is idle and its irq are not acked, it's wrong. -- Ueimor - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Thu, Jun 15, 2006 at 10:30:17PM +0200, Francois Romieu wrote: Afaik free_irq() on a shared irq does not touch the hardware and irqs are anything but synchronous. If free_irq() is issued before the device is idle and its irq are not acked, it's wrong. Correct. Before calling free_irq(), patch V3 masks interrupts on tulip and guarantees the tulip will not generate new interrupts before that call. grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Tue, Jun 13, 2006 at 10:44:12PM -0600, Grant Grundler wrote: On Tue, Jun 13, 2006 at 08:33:22PM -0400, Jeff Garzik wrote: Grant Grundler wrote: o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. You made the race window smaller, but it's still there. The chip's DMA engines should be stopped before you unregister the interrupt handler. Switching the order to be: tulip_stop_rxtx(tp);/* Stop DMA */ free_irq (dev-irq, dev); /* no more races after this */ I think the correct sequence would be: reset tulip interrupt mask flush posted write synchronize irq /* make sure we got 'em all */ tulip_stop_rxtx /* turn off dma */ free irq/* bye bye */ The synchronize irq guarantees we shouldn't see another irq generated by the card because it was held up somewhere. Cheers, Kyle M. - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Wed, Jun 14, 2006 at 09:05:06AM -0400, Kyle McMartin wrote: I think the correct sequence would be: reset tulip interrupt mask flush posted write synchronize irq /* make sure we got 'em all */ tulip_stop_rxtx /* turn off dma */ free irq/* bye bye */ The synchronize irq guarantees we shouldn't see another irq generated by the card because it was held up somewhere. Kyle, syncronize_irq() only guarantees currently executing interrupt handler completes before handing control back to the caller. It does not guarantee IRQ signals still inflight are flushed. Remember that IRQ lines are a sideband signal and not subject to PCI data ordering rules. thanks, grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler wrote: On Tue, Jun 13, 2006 at 08:33:22PM -0400, Jeff Garzik wrote: Grant Grundler wrote: o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. You made the race window smaller, but it's still there. The chip's DMA engines should be stopped before you unregister the interrupt handler. Switching the order to be: tulip_stop_rxtx(tp);/* Stop DMA */ free_irq (dev-irq, dev); /* no more races after this */ still leaves us open to IRQs being delivered _after_ we've stopped DMA. Correct. And that is the preferred, natural, logical, obvious order: 1) Turn things off. 2) Wait for activity to cease. That in turn allows the interrupt handler to re-enable DMA again. Then that would be a problem to solve... Some interrupt handlers will test netif_running() or a driver-specific shutting-down flag, specifically to avoid such behaviors. Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Wed, Jun 14, 2006 at 11:03:48AM -0400, Jeff Garzik wrote: Grant Grundler wrote: Switching the order to be: tulip_stop_rxtx(tp);/* Stop DMA */ free_irq (dev-irq, dev); /* no more races after this */ still leaves us open to IRQs being delivered _after_ we've stopped DMA. Correct. And that is the preferred, natural, logical, obvious order: 1) Turn things off. 2) Wait for activity to cease. Patch v3 does this in two stages: 1) turn off tulip interrupts 2) free_irq() calls syncronize_irq() to handle pending IRQs then calls tulip_stop_rxtx() which: 1) tells tulip to stop DMA 2) poll until DMA completes After this we can free remaining resources. That in turn allows the interrupt handler to re-enable DMA again. Then that would be a problem to solve... Some interrupt handlers will test netif_running() or a driver-specific shutting-down flag, specifically to avoid such behaviors. I'm not keen on adding more code to tulip_interrupt() routine for something that rarely happens (compared to IRQs) and is handled outside the interrupt routine. I'm pretty sure stopping interrupts before stopping DMA is sufficient. Can you show an example where it doesn't work? This is important since I'm going to propose a new Documentation/pci.txt based on this experience. thanks, grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler wrote: On Wed, Jun 14, 2006 at 11:03:48AM -0400, Jeff Garzik wrote: Grant Grundler wrote: Switching the order to be: tulip_stop_rxtx(tp);/* Stop DMA */ free_irq (dev-irq, dev); /* no more races after this */ still leaves us open to IRQs being delivered _after_ we've stopped DMA. Correct. And that is the preferred, natural, logical, obvious order: 1) Turn things off. 2) Wait for activity to cease. Patch v3 does this in two stages: 1) turn off tulip interrupts 2) free_irq() calls syncronize_irq() to handle pending IRQs then calls tulip_stop_rxtx() which: 1) tells tulip to stop DMA 2) poll until DMA completes After this we can free remaining resources. You need to turn off the thing that generates work (DMA engine), before turning off the thing that reaps work (irq handler). That in turn allows the interrupt handler to re-enable DMA again. Then that would be a problem to solve... Some interrupt handlers will test netif_running() or a driver-specific shutting-down flag, specifically to avoid such behaviors. I'm not keen on adding more code to tulip_interrupt() routine for something that rarely happens (compared to IRQs) and is handled outside the interrupt routine. I'm pretty sure stopping interrupts before stopping DMA is sufficient. Can you show an example where it doesn't work? It should be completely obvious that the chip is still generating work... You don't want to leave the hardware in a position where it has unacknowledged events. Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler [EMAIL PROTECTED] : [...] I'm not keen on adding more code to tulip_interrupt() routine for something that rarely happens (compared to IRQs) and is handled outside the interrupt routine. I'm pretty sure stopping interrupts before stopping DMA is sufficient. Can you show an example where it doesn't work? Shared irq. The device has not quiesced, the kernel stop listening to it and the neighbor device receives a late interruption from the network device. -- Ueimor - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Wed, Jun 14, 2006 at 10:47:20PM +0200, Francois Romieu wrote: Grant Grundler [EMAIL PROTECTED] : [...] I'm not keen on adding more code to tulip_interrupt() routine for something that rarely happens (compared to IRQs) and is handled outside the interrupt routine. I'm pretty sure stopping interrupts before stopping DMA is sufficient. Can you show an example where it doesn't work? Shared irq. The device has not quiesced, the kernel stop listening to it and the neighbor device receives a late interruption from the network device. I thought we've worked through that already: http://www.spinics.net/lists/netdev/msg05902.html Patch v3 takes care of that problem. The first step in the sequence is to mask IRQs on the tulip. The neighbor device sharing the IRQ will not see any interrupts from the tulip after that. thanks, grant - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Thu, Jun 08, 2006 at 11:01:20AM -0600, Grant Grundler wrote:
Here is a new patch that moves free_irq() into tulip_down().
The resulting code is structured the same as cp_close().
Val,
Two details are wrong in version 2 and are fixed in v3 (appended below):
o we don't need synchronize_irq() before calling free_irq().
(It should be removed from cp_close() too)
Thanks to willy for pointing me at kernel/irq/manage.c.
o tulip_stop_rxtx() has to be called _after_ free_irq().
ie. v2 patch didn't fix the original race condition
and when under test, dies about as fast as the original code.
Tested on rx4640 (HP IA64) for several hours.
Please apply.
thanks,
grant
Change Log:
IRQs are racing with tulip_down(). DMA can be restarted _after_
we call tulip_stop_rxtx() and the DMA buffers are unmapped.
The result is an MCA (hard crash on ia64) because of an
IO TLB miss.
Signed-off-by: Grant Grundler [EMAIL PROTECTED]
--- a/drivers/net/tulip/tulip_core.c
+++ b/drivers/net/tulip/tulip_core.c
@@ -18,11 +18,11 @@
#define DRV_NAME tulip
#ifdef CONFIG_TULIP_NAPI
-#define DRV_VERSION1.1.13-NAPI /* Keep at least for test */
+#define DRV_VERSION1.1.14-NAPI /* Keep at least for test */
#else
-#define DRV_VERSION1.1.13
+#define DRV_VERSION1.1.14
#endif
-#define DRV_RELDATEDecember 15, 2004
+#define DRV_RELDATEMay 6, 2006
#include linux/module.h
@@ -741,21 +741,20 @@ static void tulip_down (struct net_devic
/* Disable interrupts by clearing the interrupt mask. */
iowrite32 (0x, ioaddr + CSR7);
+ ioread32 (ioaddr + CSR7); /* flush posted write */
- /* Stop the Tx and Rx processes. */
- tulip_stop_rxtx(tp);
+ spin_unlock_irqrestore (tp-lock, flags);
- /* prepare receive buffers */
- tulip_refill_rx(dev);
+ free_irq (dev-irq, dev); /* no more races after this */
+ tulip_stop_rxtx(tp);/* Stop DMA */
- /* release any unconsumed transmit buffers */
- tulip_clean_tx_ring(tp);
+ /* Put driver back into the state we start with */
+ tulip_refill_rx(dev); /* prepare RX buffers */
+ tulip_clean_tx_ring(tp);/* clean up unsent TX buffers */
if (ioread32 (ioaddr + CSR6) != 0x)
tp-stats.rx_missed_errors += ioread32 (ioaddr + CSR8) 0x;
- spin_unlock_irqrestore (tp-lock, flags);
-
init_timer(tp-timer);
tp-timer.data = (unsigned long)dev;
tp-timer.function = tulip_tbl[tp-chip_id].media_timer;
@@ -774,7 +773,6 @@ static int tulip_close (struct net_devic
printk (KERN_DEBUG %s: Shutting down ethercard, status was
%2.2x.\n,
dev-name, ioread32 (ioaddr + CSR5));
- free_irq (dev-irq, dev);
/* Free all the skbuffs in the Rx queue. */
for (i = 0; i RX_RING_SIZE; i++) {
@@ -1752,7 +1752,6 @@ static int tulip_suspend (struct pci_dev
tulip_down(dev);
netif_device_detach(dev);
- free_irq(dev-irq, dev);
pci_save_state(pdev);
pci_disable_device(pdev);
-
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Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Tue, Jun 13, 2006 at 05:55:31PM -0600, Grant Grundler wrote: On Thu, Jun 08, 2006 at 11:01:20AM -0600, Grant Grundler wrote: Here is a new patch that moves free_irq() into tulip_down(). The resulting code is structured the same as cp_close(). Val, Two details are wrong in version 2 and are fixed in v3 (appended below): o we don't need synchronize_irq() before calling free_irq(). (It should be removed from cp_close() too) Thanks to willy for pointing me at kernel/irq/manage.c. o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. Tested on rx4640 (HP IA64) for several hours. Please apply. Thanks, I'll take a look next week (after the workshop and moving). -VAL - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Grant Grundler wrote: o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. You made the race window smaller, but it's still there. The chip's DMA engines should be stopped before you unregister the interrupt handler. Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
On Tue, Jun 13, 2006 at 08:33:22PM -0400, Jeff Garzik wrote: Grant Grundler wrote: o tulip_stop_rxtx() has to be called _after_ free_irq(). ie. v2 patch didn't fix the original race condition and when under test, dies about as fast as the original code. You made the race window smaller, but it's still there. The chip's DMA engines should be stopped before you unregister the interrupt handler. Switching the order to be: tulip_stop_rxtx(tp);/* Stop DMA */ free_irq (dev-irq, dev); /* no more races after this */ still leaves us open to IRQs being delivered _after_ we've stopped DMA. That in turn allows the interrupt handler to re-enable DMA again. Or are you worried about a masked, pending interrupt causing problems when the driver is re-opened or resumed? If firmware left the device in a that state at boot time wouldn't the driver be required to handle it? thanks, grant Jeff - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
