Dan Williams da87ca4d4c ioat: fix tasklet tear down ... Since commit 7787380336 "net_dma: mark broken" we no longer pin dma engines active for the network-receive-offload use case. As a result the ->free_chan_resources() that occurs after the driver self test no longer has a NET_DMA induced ->alloc_chan_resources() to back it up. A late firing irq can lead to ksoftirqd spinning indefinitely due to the tasklet_disable() performed by ->free_chan_resources(). Only ->alloc_chan_resources() can clear this condition in affected kernels. This problem has been present since commit 3e037454bc "I/OAT: Add support for MSI and MSI-X" in 2.6.24, but is now exposed. Given the NET_DMA use case is deprecated we can revisit moving the driver to use threaded irqs. For now, just tear down the irq and tasklet properly by: 1/ Disable the irq from triggering the tasklet 2/ Disable the irq from re-arming 3/ Flush inflight interrupts 4/ Flush the timer 5/ Flush inflight tasklets References: https://lkml.org/lkml/2014/1/27/282 https://lkml.org/lkml/2014/2/19/672 Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@vger.kernel.org> Reported-by: Mike Galbraith <bitbucket@online.de> Reported-by: Stanislav Fomichev <stfomichev@yandex-team.ru> Tested-by: Mike Galbraith <bitbucket@online.de> Tested-by: Stanislav Fomichev <stfomichev@yandex-team.ru> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>		2014-02-25 09:44:20 -08:00
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dca.c	ioat/dca: Update DCA BIOS workarounds to use TAINT_FIRMWARE_WORKAROUND	2013-03-22 12:55:38 -04:00
dma_v2.c	ioat: fix tasklet tear down	2014-02-25 09:44:20 -08:00
dma_v2.h	ioatdma: clean up sed pool kmem_cache	2013-11-14 11:04:41 -08:00
dma_v3.c	ioat: fix tasklet tear down	2014-02-25 09:44:20 -08:00
dma.c	ioat: fix tasklet tear down	2014-02-25 09:44:20 -08:00
dma.h	ioat: fix tasklet tear down	2014-02-25 09:44:20 -08:00
hw.h	drivers/dma: remove unused support for MEMSET operations	2013-07-03 16:07:42 -07:00
Makefile	drivers/dma/ioat: Use the ccflag-y instead of EXTRA_CFLAGS	2010-12-04 15:03:06 -08:00
pci.c	ioatdma: clean up sed pool kmem_cache	2013-11-14 11:04:41 -08:00
registers.h	ioatdma: Adding write back descriptor error status support for ioatdma 3.3	2013-04-15 22:46:15 +05:30