Based upon a lockdep report.
Since ->poll() can be invoked from netpoll with interrupts
disabled, we must not unconditionally enable interrupts
in napi_complete().
Instead we must use local_irq_{save,restore}().
Noticed by Peter Zijlstra:
<irqs disabled>
netpoll_poll()
poll_napi()
spin_trylock(&napi->poll_lock)
poll_one_napi()
napi->poll() := sky2_poll()
napi_complete()
local_irq_disable()
local_irq_enable() <--- *BUG*
<irq>
irq_exit()
do_softirq()
net_rx_action()
spin_lock(&napi->poll_lock) <--- Deadlock!
Because we still hold the lock....
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
ahci: Add Marvell 6121 SATA support
pata_ali: use atapi_cmd_type() to determine cmd type instead of transfer size
ahci: implement skip_host_reset parameter
ahci: request all PCI BARs
devres: implement pcim_iomap_regions_request_all()
libata-acpi: improve dock event handling
Some drivers need to reserve all PCI BARs to prevent other drivers
misusing unoccupied BARs. pcim_iomap_regions_request_all() requests
all BARs and iomap specified BARs.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
There is a race in virtio_net, dealing with disabling/enabling the callback.
I saw the following oops:
kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:218!
illegal operation: 0001 [#1] SMP
Modules linked in: sunrpc dm_mod
CPU: 2 Not tainted 2.6.25-rc1zlive-host-10623-gd358142-dirty #99
Process swapper (pid: 0, task: 000000000f85a610, ksp: 000000000f873c60)
Krnl PSW : 0404300180000000 00000000002b81a6 (vring_disable_cb+0x16/0x20)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
Krnl GPRS: 0000000000000001 0000000000000001 0000000010005800 0000000000000001
000000000f3a0900 000000000f85a610 0000000000000000 0000000000000000
0000000000000000 000000000f870000 0000000000000000 0000000000001237
000000000f3a0920 000000000010ff74 00000000002846f6 000000000fa0bcd8
Krnl Code: 00000000002b819a: a7110001 tmll %r1,1
00000000002b819e: a7840004 brc 8,2b81a6
00000000002b81a2: a7f40001 brc 15,2b81a4
>00000000002b81a6: a51b0001 oill %r1,1
00000000002b81aa: 40102000 sth %r1,0(%r2)
00000000002b81ae: 07fe bcr 15,%r14
00000000002b81b0: eb7ff0380024 stmg %r7,%r15,56(%r15)
00000000002b81b6: a7f13e00 tmll %r15,15872
Call Trace:
([<000000000fa0bcd0>] 0xfa0bcd0)
[<00000000002b8350>] vring_interrupt+0x5c/0x6c
[<000000000010ab08>] do_extint+0xb8/0xf0
[<0000000000110716>] ext_no_vtime+0x16/0x1a
[<0000000000107e72>] cpu_idle+0x1c2/0x1e0
The problem can be triggered with a high amount of host->guest traffic.
I think its the following race:
poll says netif_rx_complete
poll calls enable_cb
enable_cb opens the interrupt mask
a new packet comes, an interrupt is triggered----\
enable_cb sees that there is more work |
enable_cb disables the interrupt |
. V
. interrupt is delivered
. skb_recv_done does atomic napi test, ok
some waiting disable_cb is called->check fails->bang!
.
poll would do napi check
poll would do disable_cb
The fix is to let enable_cb not disable the interrupt again, but expect the
caller to do the cleanup if it returns false. In that case, the interrupt is
only disabled, if the napi test_set_bit was successful.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned up doco)
The comments in the definition of struct export_operations don't match the
current members.
Add a comment for the 2 new functions and remove 2 comments for unused ones.
Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PCI busses can be registered multiple times, so we need to detect if we
have registered our bus structure in sysfs already. If so, don't do it
again.
Thanks to Guennadi Liakhovetski <g.liakhovetski@gmx.de> for reporting
the problem, and to Linus for poking me to get me to believe that it was
a real problem.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When building drivers/macintosh/mediabay.c if CONFIG_ADB_PMU isn't
defined we get:
drivers/built-in.o: In function `media_bay_step':
mediabay.c:(.text+0x92b84): undefined reference to `pmu_suspend'
mediabay.c:(.text+0x92c08): undefined reference to `pmu_resume'
Create empty place holders in that scenario.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
pmu_sys_suspended is declared extern when:
defined(CONFIG_PM_SLEEP) && defined(CONFIG_PPC32)
but only defined when:
defined(CONFIG_SUSPEND) && defined(CONFIG_PPC32)
which is wrong. Let's fix that.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
[SCTP]: Fix local_addr deletions during list traversals.
net: fix build with CONFIG_NET=n
[TCP]: Prevent sending past receiver window with TSO (at last skb)
rt2x00: Add new D-Link USB ID
rt2x00: never disable multicast because it disables broadcast too
libertas: fix the 'compare command with itself' properly
drivers/net/Kconfig: fix whitespace for GELIC_WIRELESS entry
[NETFILTER]: nf_queue: don't return error when unregistering a non-existant handler
[NETFILTER]: nfnetlink_queue: fix EPERM when binding/unbinding and instance 0 exists
[NETFILTER]: nfnetlink_log: fix EPERM when binding/unbinding and instance 0 exists
[NETFILTER]: nf_conntrack: replace horrible hack with ksize()
[NETFILTER]: nf_conntrack: add \n to "expectation table full" message
[NETFILTER]: xt_time: fix failure to match on Sundays
[NETFILTER]: nfnetlink_log: fix computation of netlink skb size
[NETFILTER]: nfnetlink_queue: fix computation of allocated size for netlink skb.
[NETFILTER]: nfnetlink: fix ifdef in nfnetlink_compat.h
[NET]: include <linux/types.h> into linux/ethtool.h for __u* typedef
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
RxRPC: fix rxrpc_recvmsg()'s returning of msg_name
net/enc28j60: oops fix
...
It was all wrapped in '#ifdef CONFIG_BLOCK' anyway, so userspace was
getting nothing useful out of it. And the special #ifndef __KERNEL__
version of 'struct partition' makes me inclined to promote an attitude
of violence...
Stick some comments on some of the #endifs too, while we're at it.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduced in commit-id 9e2779fa28 and
ifdef'ed out for nommu in 8ca3ed87db, both
approaches end up breaking the nommu build in different ways. An
impressive feat for a 2-liner.
Current is_vmalloc_addr() users fall in to two camps:
- Determining whether to use vfree()/kfree()
- Whether to do vmlist traversal (only /proc/kcore).
Since we don't support /proc/kcore on nommu, that leaves the
vfree()/kfree() determination use cases. nommu vfree() happens to be a
wrapper to kfree() anyways, so is_vmalloc_addr() can always return 0
and end up with the right behaviour.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6:
drivers: fix dma_get_required_mask
firmware: provide stubs for the FW_LOADER=n case
nozomi: fix initialization and early flow control access
sysdev: fix problem with sysdev_class being re-registered
Additional input received from JMicron on MemoryStick host interfaces showed
that some assumtions in fifo handling code were incorrect. This patch also
fixes data corruption used to occure during PIO transfers.
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thanks to some input from kind people at JMicron it is now possible to have
more correct definitions of protocol structures and bit field semantics.
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since the header file gadget.h isn't being exported to userspace,
there seems to be little point having a __KERNEL__ proprocessor check.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since the header file g_printer.h doesn't depend on __KERNEL__,
there's no need to unifdef it in the Kbuild file.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
