30 Jun, 2010
1 commit
-
Apparently "pid-1" confuses people...
Requested-by: Randy Dunlap
Signed-off-by: Peter Zijlstra
Cc: torvalds@linux-foundation.org
Cc: randy.dunlap@oracle.com
Cc: Ilya Loginov
LKML-Reference:
Signed-off-by: Ingo Molnar
29 Jun, 2010
1 commit
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Ilya reported that on a very slow machine he could reliably
reproduce a race between forking init and kthreadd. We first
fork init so that it obtains pid-1, however since the scheduler
is already fully running at this point it can preempt and run
the init thread before we spawn and set kthreadd_task.The init thread can then attempt spawning kthreads without
kthreadd being present which results in an OOPS.Reported-by: Ilya Loginov
Signed-off-by: Peter Zijlstra
Acked-by: Linus Torvalds
LKML-Reference:
Signed-off-by: Ingo Molnar
25 Jun, 2010
1 commit
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GCC 4.4.1 on ARM has been observed to replace the while loop in
sched_avg_update with a call to uldivmod, resulting in the
following build failure at link-time:kernel/built-in.o: In function `sched_avg_update':
kernel/sched.c:1261: undefined reference to `__aeabi_uldivmod'
kernel/sched.c:1261: undefined reference to `__aeabi_uldivmod'
make: *** [.tmp_vmlinux1] Error 1This patch introduces a fake data hazard to the loop body to
prevent the compiler optimising the loop away.Signed-off-by: Will Deacon
Signed-off-by: Andrew Morton
Acked-by: Peter Zijlstra
Cc: Catalin Marinas
Cc: Russell King
Cc: Linus Torvalds
Cc:
Signed-off-by: Ingo Molnar
18 Jun, 2010
1 commit
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Commit e70971591 ("sched: Optimize unused cgroup configuration") introduced
an imbalanced scheduling bug.If we do not use CGROUP, function update_h_load won't update h_load. When the
system has a large number of tasks far more than logical CPU number, the
incorrect cfs_rq[cpu]->h_load value will cause load_balance() to pull too
many tasks to the local CPU from the busiest CPU. So the busiest CPU keeps
going in a round robin. That will hurt performance.The issue was found originally by a scientific calculation workload that
developed by Yanmin. With that commit, the workload performance drops
about 40%.CPU before after
00 : 2 : 7
01 : 1 : 7
02 : 11 : 6
03 : 12 : 7
04 : 6 : 6
05 : 11 : 7
06 : 10 : 6
07 : 12 : 7
08 : 11 : 6
09 : 12 : 6
10 : 1 : 6
11 : 1 : 6
12 : 6 : 6
13 : 2 : 6
14 : 2 : 6
15 : 1 : 6Reviewed-by: Yanmin zhang
Signed-off-by: Alex Shi
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
09 Jun, 2010
1 commit
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PROVE_RCU has a few issues with the cpu_cgroup because the scheduler
typically holds rq->lock around the css rcu derefs but the generic
cgroup code doesn't (and can't) know about that lock.Provide means to add extra checks to the css dereference and use that
in the scheduler to annotate its users.The addition of rq->lock to these checks is correct because the
cgroup_subsys::attach() method takes the rq->lock for each task it
moves, therefore by holding that lock, we ensure the task is pinned to
the current cgroup and the RCU derefence is valid.That leaves one genuine race in __sched_setscheduler() where we used
task_group() without holding any of the required locks and thus raced
with the cgroup code. Solve this by moving the check under the
appropriate lock.Signed-off-by: Peter Zijlstra
Cc: "Paul E. McKenney"
LKML-Reference:
Signed-off-by: Ingo Molnar
08 Jun, 2010
6 commits
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* git://git.infradead.org/~dwmw2/mtd-2.6.35:
jffs2: update ctime when changing the file's permission by setfacl
jffs2: Fix NFS race by using insert_inode_locked()
jffs2: Fix in-core inode leaks on error paths
mtd: Fix NAND submenu
mtd/r852: update card detect early.
mtd/r852: Fixes in case of DMA timeout
mtd/r852: register IRQ as last step
drivers/mtd: Use memdup_user
docbook: make mtd nand module init static -
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
ahci: redo stopping DMA engines on empty ports
sata_sil24: fix kernel panic on ARM caused by unaligned access in sata_sil24
ahci: add pci quirk for JMB362
sata_via: explain the magic fix -
Commit 96d60303fd (ahci: Turn off DMA engines when there's no device)
implemented stopping DMA engines on empty ports but it used single
sampling of status registers to determine device presence which led to
disabling of DMA engines on occupied ports. Do it after all EH
actions are complete using device presence state determined by EH.
This avoids spurious disabling of DMA engines and simplifies the code.Signed-off-by: Tejun Heo
Tested-by: Marc Dionne
Cc: Matthew Garrett
Cc: Robert Hancock
Signed-off-by: Jeff Garzik -
The sata_sil24 driver has six 16-bit registers that are initialised with
32-bit writes. This cause a kernel panic on ARM due to the unaligned
accesses which result.This patch changes the accesses to the correct 16-bit ones.
Signed-off-by: Colin Tuckley
Signed-off-by: Tejun Heo
Signed-off-by: Jeff Garzik -
JMB362 is a new variant of jmicron controller which is similar to
JMB360 but has two SATA ports instead of one. As there is no PATA
port, single function AHCI mode can be used as in JMB360. Add pci
quirk for JMB362.Signed-off-by: Tejun Heo
Reported-by: Aries Lee
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik -
Add Joseph Chan's explanation of the problem and workaround to the
VT6421 magic fix.Signed-off-by: Tejun Heo
Cc: Joseph Chan
Signed-off-by: Jeff Garzik
07 Jun, 2010
2 commits
-
At the point of the call to dev_err, wm8350 is NULL.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)//
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@if ((E == NULL && ...) || ...)
{
... when != if (...) S1 else S2
when != E = E1
* E->f
... when any
return ...;
}
else S3
//Signed-off-by: Julia Lawall
Acked-by: Mark Brown
Signed-off-by: Wim Van Sebroeck -
This reverts commit 962400e8fd29981a7b166e463dd143b6ac6a3e76, which was
entirely bogus.The code used to multiply the character offset by "vc->vc_cols", and
that's actually correct, because 'd' itself is an 'unsigned short'. So
the pointer arithmetic already takes the size of a VGA character into
account. Changing it to use vc_size_row (which is just "vc_cols"
shifted up to take the size of the character into account) ends up
multiplying with the VGA character size twice.This got reported as bugs for various other subsystems, because what it
actually results in is writing the 16-bit vc_video_erase_char pattern
(usually 0x0720: 0x07 is the default attribute, 0x20 is ASCII space)
into some random other allocation.So Markus ended up reporting this as a ext4 bug, while to Torsten Kaiser
it looked like a problem with KMS or libata. Jeff Chua saw it in
different places.And finally - Justin Mattock had slab poisoning enabled, and saw it as a
slab poison overwritten. And bisected and reverted this to verify the
buggy commit.Reported-by: Markus Trippelsdorf
Reported-by: Torsten Kaiser
Reported-by: Jeff Chua
Reported-by: Justin P. Mattock
Reported-bisected-and-tested-by: Justin P. Mattock
Acked-by: Dave Airlie
Cc: Frank Pan
Cc: Greg Kroah-Hartman
Signed-off-by: Linus Torvalds
06 Jun, 2010
4 commits
-
jffs2 didn't update the ctime of the file when its permission was changed.
Steps to reproduce:
# touch aaa
# stat -c %Z aaa
1275289822
# setfacl -m 'u::x,g::x,o::x' aaa
# stat -c %Z aaa
1275289822 .Signed-off-by: Jan Kara
Signed-off-by: David Woodhouse -
Cursors need to be in the GTT domain when being accessed by the GPU.
Previously this was a fortuitous byproduct of userspace using pwrite()
to upload the image data into the cursor. The redundant clflush was
removed in commit 9b8c4a and so the image was no longer being flushed
out of the caches into main memory. One could also devise a scenario
where the cursor was rendered by the GPU, prior to being attached as the
cursor, resulting in similar corruption due to the missing MI_FLUSH.Fixes:
Bug 28335 - Cursor corruption caused by commit 9b8c4a0b21
https://bugs.freedesktop.org/show_bug.cgi?id=28335Signed-off-by: Chris Wilson
Reported-and-tested-by: Jeff Chua
Tested-by: Linus Torvalds
Reported-by: Andy Isaacson
Signed-off-by: Linus Torvalds -
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Fix remaining racy updates of EXT4_I(inode)->i_flags
ext4: Make sure the MOVE_EXT ioctl can't overwrite append-only files
05 Jun, 2010
23 commits
-
A few functions were still modifying i_flags in a racy manner.
Signed-off-by: Dmitry Monakhov
Signed-off-by: "Theodore Ts'o" -
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: improve xfs_isilocked
xfs: skip writeback from reclaim context
xfs: remove done roadmap item from xfs-delayed-logging-design.txt
xfs: fix race in inode cluster freeing failing to stale inodes
xfs: fix access to upper inodes without inode64
xfs: fix might_sleep() warning when initialising per-ag tree
fs/xfs/quota: Add missing mutex_unlock
xfs: remove duplicated #include
xfs: convert more trace events to DEFINE_EVENT
xfs: xfs_trace.c: remove duplicated #include
xfs: Check new inode size is OK before preallocating
xfs: clean up xlog_align
xfs: cleanup log reservation calculactions
xfs: be more explicit if RT mount fails due to config
xfs: replace E2BIG with EFBIG where appropriate -
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (30 commits)
X25: remove duplicated #include
tcp: use correct net ns in cookie_v4_check()
rps: tcp: fix rps_sock_flow_table table updates
ppp_generic: fix multilink fragment sizes
syncookies: remove Kconfig text line about disabled-by-default
ixgbe: only check pfc bits in hang logic if pfc is enabled
net: check for refcount if pop a stacked dst_entry
ixgbe: return IXGBE_ERR_RAR_INDEX when out of range
act_pedit: access skb->data safely
sfc: Store port number in net_device::dev_id
epic100: Test __BIG_ENDIAN instead of (non-existent) CONFIG_BIG_ENDIAN
tehuti: return -EFAULT on copy_to_user errors
isdn/kcapi: return -EFAULT on copy_from_user errors
e1000e: change logical negate to bitwise
sfc: Get port number from CS_PORT_NUM, not PCI function number
cls_u32: use skb_header_pointer() to dereference data safely
TCP: tcp_hybla: Fix integer overflow in slow start increment
act_nat: fix the wrong checksum when addr isn't in old_addr/mask
net/fec: fix pm to survive to suspend/resume
korina: count RX DMA OVR as rx_fifo_error
... -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
nilfs2: remove obsolete declarations of cache constructor and destructor
nilfs2: fix style issue in nilfs_destroy_cachep -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
Minix: Clean up left over label
fix truncate inode time modification breakage
fix setattr error handling in sysfs, configfs
fcntl: return -EFAULT if copy_to_user fails
wrong type for 'magic' argument in simple_fill_super()
fix the deadlock in qib_fs
mqueue doesn't need make_bad_inode() -
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
module: fix bne2 "gave up waiting for init of module libcrc32c"
module: verify_export_symbols under the lock
module: move find_module check to end
module: make locking more fine-grained.
module: Make module sysfs functions private.
module: move sysfs exposure to end of load_module
module: fix kdb's illicit use of struct module_use.
module: Make the 'usage' lists be two-way -
Problem: it's hard to avoid an init routine stumbling over a
request_module these days. And it's not clear it's always a bad idea:
for example, a module like kvm with dynamic dependencies on kvm-intel
or kvm-amd would be neater if it could simply request_module the right
one.In this particular case, it's libcrc32c:
libcrc32c_mod_init
crypto_alloc_shash
crypto_alloc_tfm
crypto_find_alg
crypto_alg_mod_lookup
crypto_larval_lookup
request_moduleIf another module is waiting inside resolve_symbol() for libcrc32c to
finish initializing (ie. bne2 depends on libcrc32c) then it does so
holding the module lock, and our request_module() can't make progress
until that is released.Waiting inside resolve_symbol() without the lock isn't all that hard:
we just need to pass the -EBUSY up the call chain so we can sleep
where we don't hold the lock. Error reporting is a bit trickier: we
need to copy the name of the unfinished module before releasing the
lock.Other notes:
1) This also fixes a theoretical issue where a weak dependency would allow
symbol version mismatches to be ignored.
2) We rename use_module to ref_module to make life easier for the only
external user (the out-of-tree ksplice patches).Signed-off-by: Rusty Russell
Cc: Linus Torvalds
Cc: Tim Abbot
Tested-by: Brandon Philips -
It disabled preempt so it was "safe", but nothing stops another module
slipping in before this module is added to the global list now we don't
hold the lock the whole time.So we check this just after we check for duplicate modules, and just
before we put the module in the global list.(find_symbol finds symbols in coming and going modules, too).
Signed-off-by: Rusty Russell
-
I think Rusty may have made the lock a bit _too_ finegrained there, and
didn't add it to some places that needed it. It looks, for example, like
PATCH 1/2 actually drops the lock in places where it's needed
("find_module()" is documented to need it, but now load_module() didn't
hold it at all when it did the find_module()).Rather than adding a new "module_loading" list, I think we should be able
to just use the existing "modules" list, and just fix up the locking a
bit.In fact, maybe we could just move the "look up existing module" a bit
later - optimistically assuming that the module doesn't exist, and then
just undoing the work if it turns out that we were wrong, just before
adding ourselves to the list.Signed-off-by: Rusty Russell
-
Kay Sievers reports that we still have some
contention over module loading which is slowing boot.Linus also disliked a previous "drop lock and regrab" patch to fix the
bne2 "gave up waiting for init of module libcrc32c" message.This is more ambitious: we only grab the lock where we need it.
Signed-off-by: Rusty Russell
Cc: Brandon Philips
Cc: Kay Sievers
Cc: Linus Torvalds -
These were placed in the header in ef665c1a06 to get the various
SYSFS/MODULE config combintations to compile.That may have been necessary then, but it's not now. These functions
are all local to module.c.Signed-off-by: Rusty Russell
Cc: Randy Dunlap -
This means a little extra work, but is more logical: we don't put
anything in sysfs until we're about to put the module into the
global list an parse its parameters.This also gives us a logical place to put duplicate module detection
in the next patch.Signed-off-by: Rusty Russell
-
Linus changed the structure, and luckily this didn't compile any more.
Reported-by: Stephen Rothwell
Signed-off-by: Rusty Russell
Cc: Jason Wessel
Cc: Martin Hicks -
When adding a module that depends on another one, we used to create a
one-way list of "modules_which_use_me", so that module unloading could
see who needs a module.It's actually quite simple to make that list go both ways: so that we
not only can see "who uses me", but also see a list of modules that are
"used by me".In fact, we always wanted that list in "module_unload_free()": when we
unload a module, we want to also release all the other modules that are
used by that module. But because we didn't have that list, we used to
first iterate over all modules, and then iterate over each "used by me"
list of that module.By making the list two-way, we simplify module_unload_free(), and it
allows for some trivial fixes later too.Signed-off-by: Linus Torvalds
Signed-off-by: Rusty Russell (cleaned & rebased) -
Remove duplicated #include('s) in drivers/net/wan/x25_asy.c
Signed-off-by: Huang Weiyi
Signed-off-by: David S. Miller -
Its better to make a route lookup in appropriate namespace.
Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller -
I believe a moderate SYN flood attack can corrupt RFS flow table
(rps_sock_flow_table), making RPS/RFS much less effective.Even in a normal situation, server handling short lived sessions suffer
from bad steering for the first data packet of a session, if another SYN
packet is received for another session.We do following action in tcp_v4_rcv() :
sock_rps_save_rxhash(sk, skb->rxhash);
We should _not_ do this if sk is a LISTEN socket, as about each
packet received on a LISTEN socket has a different rxhash than
previous one.
-> RPS_NO_CPU markers are spread all over rps_sock_flow_table.Also, it makes sense to protect sk->rxhash field changes with socket
lock (We currently can change it even if user thread owns the lock
and might use rxhash)This patch moves sock_rps_save_rxhash() to a sock locked section,
and only for non LISTEN sockets.Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller -
Fix bug in multilink fragment size calculation introduced by
commit 9c705260feea6ae329bc6b6d5f6d2ef0227eda0a
"ppp: ppp_mp_explode() redesign"Signed-off-by: Ben McKeegan
Signed-off-by: David S. Miller -
syncookies default to on since
e994b7c901ded7200b525a707c6da71f2cf6d4bb
(tcp: Don't make syn cookies initial setting depend on CONFIG_SYSCTL).Signed-off-by: Florian Westphal
Signed-off-by: David S. Miller -
Only check pfc bits in hang logic if PFC is enabled. Previously,
if DCB was enabled but PFC was disabled the incorrect pause
bits would be checked.Signed-off-by: John Fastabend
Acked-by: Don Skidmore
Signed-off-by: Jeff Kirsher
Signed-off-by: David S. Miller -
xfrm triggers a warning if dst_pop() drops a refcount
on a noref dst. This patch changes dst_pop() to
skb_dst_pop(). skb_dst_pop() drops the refcnt only
on a refcounted dst. Also we don't clone the child
dst_entry, so it is not refcounted and we can use
skb_dst_set_noref() in xfrm_output_one().Signed-off-by: Steffen Klassert
Signed-off-by: Eric Dumazet
Signed-off-by: David S. Miller -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: wacom - add Cintiq 21UX2 and Intuos4 WL
Input: ads7846 - fix compiler warning in ads7846_probe()
Input: tps6507x-ts - a couple work queue cleanups
Input: s3c2410_ts - tone down logging
Input: s3c2410_ts - fix build error due to ADC Kconfig rename -
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (23 commits)
sh: Make intc messages consistent via pr_fmt.
sh: make sure static declaration on ms7724se
sh: make sure static declaration on mach-migor
sh: make sure static declaration on mach-ecovec24
sh: make sure static declaration on mach-ap325rxa
clocksource: sh_cmt: compute mult and shift before registration
clocksource: sh_tmu: compute mult and shift before registration
sh: PIO disabling for x3proto and urquell.
sh: mach-sdk7786: conditionally disable PIO support.
sh: support for platforms without PIO.
usb: r8a66597-hcd pio to mmio accessor conversion.
usb: gadget: r8a66597-udc pio to mmio accessor conversion.
usb: gadget: m66592-udc pio to mmio accessor conversion.
sh: add romImage MMCIF boot for sh7724 and Ecovec V2
sh: add boot code to MMCIF driver header
sh: prepare MMCIF driver header file
sh: allow romImage data between head.S and the zero page
sh: Add support MMCIF for ecovec
sh: remove duplicated #include
input: serio: disable i8042 for non-cayman sh platforms.
...
