This fixes a race during initialization with the NAPI softirq
processing by using an RCU approach.
This race was discovered when refill_skbs() was added to
the setup code.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
we could do one thing (see the patch below): i think it would be useful
to fill up the netlogging skb queue straight at initialization time.
Especially if netpoll is used for dumping alone, the system might not be
in a situation to fill up the queue at the point of crash, so better be
a bit more prepared and keep the pipeline filled.
[ I've modified this to be called earlier - mpm ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add limited retry logic to netpoll_send_skb
Each time we attempt to send, decrement our per-device retry counter.
On every successful send, we reset the counter.
We delay 50us between attempts with up to 20000 retries for a total of
1 second. After we've exhausted our retries, subsequent failed
attempts will try only once until reset by success.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor netpoll_send_skb restructuring
Restructure to avoid confusing goto and move some bits out of the
retry loop.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Suggested by Steven Rostedt, matches his patch included in e100.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes an obvious deadlock in the netpoll code. netpoll_rx takes the
npinfo->rx_lock. netpoll_rx is also the only caller of arp_reply (through
__netpoll_rx). As such, it is not necessary to take this lock.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initialize npinfo->rx_flags. The way it stands now, this will have random
garbage, and so will incur a locking penalty even when an rx_hook isn't
registered and we are not active in the netpoll polling code.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are many instances of
skb->protocol = htons(ETH_P_*);
skb->protocol = __constant_htons(ETH_P_*);
and
skb->protocol = *_type_trans(...);
Most of *_type_trans() are already endian-annotated, so, let's shift
attention on other warnings.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Well I've only found one potential cause for the assertion
failure in tcp_mark_head_lost. First of all, this can only
occur if cnt > 1 since tp->packets_out is never zero here.
If it did hit zero we'd have much bigger problems.
So cnt is equal to fackets_out - reordering. Normally
fackets_out is less than packets_out. The only reason
I've found that might cause fackets_out to exceed packets_out
is if tcp_fragment is called from tcp_retransmit_skb with a
TSO skb and the current MSS is greater than the MSS stored
in the TSO skb. This might occur as the result of an expiring
dst entry.
In that case, packets_out may decrease (line 1380-1381 in
tcp_output.c). However, fackets_out is unchanged which means
that it may in fact exceed packets_out.
Previously tcp_retrans_try_collapse was the only place where
packets_out can go down and it takes care of this by decrementing
fackets_out.
So we should make sure that fackets_out is reduced by an appropriate
amount here as well.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We have a chek in there to make sure that the name won't overflow
task_struct.comm[], but it's triggering for scsi with lots of HBAs, only
scsi is using single-threaded workqueues which don't append the "/%d"
anyway.
All too hard. Just kill the BUG_ON.
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
[ kthread_create() uses vsnprintf() and limits the thing, so no
actual overflow can actually happen regardless ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Even though the changes are minor for the next release an increasing
version number simplifies my support issues.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The workaround for broken device-tree that prevents fan control from
working on recent G5 models need to be "enabled" for machines with
revision 0x37 of the bridge in addition to machines with revision 0x35.
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Need to use list_for_entry_safe(), as we're removing items during the
traversal. list_for_each_entry() uses the first ptr also as an iterator, if
you kfree() it slab takes it, might poison it and then you try to use it to
iterate to the next object in list.
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix the p-persistence CSMA algorithm which in simplex mode was starting
with a slottime delay before doing anything else as if there was carrier
collision resulting in bad performance on simplex links.
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sata_sx4 directly references sg->length to calculate total_len in
pdc20621_dma_prep(). This is incorrect as dma_map_sg() could have
merged multiple sg's into one and, in such case, sg->length doesn't
reflect true size of the entry. This patch makes it use
sg_dma_len(sg).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Patch from Ben Dooks
Rename the s3c2410_report_oc() to s3c2410_usb_report_oc()
as this is an usb specific function.
Change port power on the usb-simtec implementation to only
power up the output if both are set, as per the usb 1.1
specification
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Ben Dooks
Documentation for the in-built OHCI host controller
and the support for it in Linux.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, we can't use the "user" bit in the page tables to
control whether a page table entry is "global" or "asid" specific,
since the vector page is mapped as "user" accessible but is not
process specific.
Therefore, give direct control of the ARMv6 "nG" (not global)
bit to the mm layers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1. Move hwif_to_node to ide.h
2. Use hwif_to_node in ide-disk.c
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the tda9887 stuff from lgdt330x.c. It's experimental code
which wasn't supposed to leak out and we don't want it in 2.6.13.
Signed-off-by: Michael Krufky <mkrufky@m1k.net>
Acked-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Two trivial text changes in Kconfig and lgdt330x.c
Signed-off-by: Michael Krufky <mkrufky@m1k.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Added pci_request_regions() before using the controller to avoid duplicate
usage of the I2O controller when the dpt_i2o driver and I2O subsystem is
loaded at the same time.
Signed-off-by: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
From: Dave Johnson <djohnson+linux-kernel@sw.starentnetworks.com>
sendmsg()/recvmsg() syscalls from o32/n32 apps to a 64bit kernel will
cause a kernel memory leak if iov_len > UIO_FASTIOV for each syscall!
This is because both sys_sendmsg() and verify_compat_iovec() kmalloc a
new iovec structure. Only the one from sys_sendmsg() is free'ed.
I wrote a simple test program to confirm this after identifying the
problem:
http://davej.org/programs/testsendmsg.c
Note that the below fix will break solaris_sendmsg()/solaris_recvmsg() as
it also calls verify_compat_iovec() but expects it to malloc internally.
[ I fixed that. -DaveM ]
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to divide, not multiply. While we're here,
use NSEC_PER_USEC instead of a magic constant.
Based upon a report from Josip Loncaric and a patch
by Andrew Morton.
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver already depends on CONFIG_PCI in Kconfig.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
envctrl currently uses very odd ways to stop a thread, using various
things that should be exposed to drivers at all.
This patch (which is untested as I don't have sparc hardware) switches
it to use the proper kthread infrastructure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove new configuration API from i2o_config
The API-patch is still available from the I2O website (which is mentioned in
the kernel config now). It is removed because it creates a new binary
sysfs-attribute, which doesn't have the limitiation of 4k. Expect for the
Adaptec controllers, which has a limitation in the hardware this attribute
doesn't make sense anywhere else. Until the sysfs API provides an attribute
which doesn't buffer (like firmware) and let access to at least 64k blocks i
provide a separate patch...
(akpm: basically, this API was introduced post-2.6.12 and Markus wants to pull
it out before 2.6.13).
Signed-off-by: Markus Lidel <Markus.Lidel@shadowconnect.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fixed problems so we can build with gcc-4.0.1
Signed-off-by: Peter Schaefer-Hutter <peter.schaefer-hutter@tfk-racoms.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Makes dpram allocations work
* Makes non-console UART work on both 8xx and 82xx
* Fixed whitespace in files that were touched
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Pantelis Antoniou <panto@intracom.gr>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix possible cpuset_sem ABBA deadlock if 'notify_on_release' set.
For a particular usage pattern, creating and destroying cpusets fairly
frequently using notify_on_release, on a very large system, this deadlock
can be seen every few days. If you are not using the cpuset
notify_on_release feature, you will never see this deadlock.
The existing code, on task exit (or cpuset deletion) did:
get cpuset_sem
if cpuset marked notify_on_release and is ready to release:
compute cpuset path relative to /dev/cpuset mount point
call_usermodehelper() forks /sbin/cpuset_release_agent with path
drop cpuset_sem
Unfortunately, the fork in call_usermodehelper can allocate memory, and
allocating memory can require cpuset_sem, if the mems_generation values
changed in the interim. This results in an ABBA deadlock, trying to obtain
cpuset_sem when it is already held by the current task.
To fix this, I put the cpuset path (which must be computed while holding
cpuset_sem) in a temporary buffer, to be used in the call_usermodehelper
call of /sbin/cpuset_release_agent only _after_ dropping cpuset_sem.
So the new logic is:
get cpuset_sem
if cpuset marked notify_on_release and is ready to release:
compute cpuset path relative to /dev/cpuset mount point
stash path in kmalloc'd buffer
drop cpuset_sem
call_usermodehelper() forks /sbin/cpuset_release_agent with path
free path
The sharp eyed reader might notice that this patch does not contain any
calls to kmalloc. The existing code in the check_for_release() routine was
already kmalloc'ing a buffer to hold the cpuset path. In the old code, it
just held the buffer for a few lines, over the cpuset_release_agent() call
that in turn invoked call_usermodehelper(). In the new code, with the
application of this patch, it returns that buffer via the new char
**ppathbuf parameter, for later use and freeing in cpuset_release_agent(),
which is called after cpuset_sem is dropped. Whereas the old code has just
one call to cpuset_release_agent(), right in the check_for_release()
routine, the new code has three calls to cpuset_release_agent(), from the
various places that a cpuset can be released.
This patch has been build and booted on SN2, and passed a stress test that
previously hit the deadlock within a few seconds.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
i8xx_tco.c v0.08: only "arm" the watchdog when the watchdog has been
started. (Kernel Bug 4251: system reset when battery is read and i8xx_tco
driver loaded)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>