Fix a UML hang in which everything would just stop until some I/O happened
- a ping, someone whacking the keyboard - at which point everything would
start up again as though nothing had happened.
The cause was gcc reordering some code which absolutely needed to be
executed in the order in the source. When unblock_signals switches signals
from off to on, it needs to see if any interrupts had happened in the
critical section. The interrupt handlers check signals_enabled - if it is
zero, then the handler adds a bit to the "pending" bitmask and returns.
unblock_signals checks this mask to see if any signals need to be
delivered.
The crucial part is this:
signals_enabled = 1;
save_pending = pending;
if(save_pending == 0)
return;
pending = 0;
In order to avoid an interrupt arriving between reading pending and setting
it to zero, in which case, the record of the interrupt would be erased,
signals are enabled.
What happened was that gcc reordered this so that 'save_pending = pending'
came before 'signals_enabled = 1', creating a one-instruction window within
which an interrupt could arrive, set its bit in pending, and have it be
immediately erased.
When the I/O workload is purely disk-based, the loss of a block device
interrupt stops the entire I/O system because the next block request will
wait for the current one to finish. Thus the system hangs until something
else causes some I/O to arrive, such as a network packet or console input.
The fix to this particular problem is a memory barrier between enabling
signals and reading the pending signal mask. An xchg would also probably
work.
Looking over this code for similar problems led me to do a few more
things:
- make signals_enabled and pending volatile so that they don't get cached
in registers
- add an mb() to the return paths of block_signals and unblock_signals so
that the modification of signals_enabled doesn't get shuffled into the
caller in the event that these are inlined in the future.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Callers after reiserfs_init_bitmap_cache() expect errval to contain -EINVAL
until much later. If a condition fails before errval is reset later,
reiserfs_fill_super() will mistakenly return 0, causing an Oops in
do_add_mount(). This patch resets errval to -EINVAL after the call.
I view this as a temporary fix and real error codes should be used
throughout reiserfs_fill_super().
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
WARNING: vmlinux - Section mismatch: reference to .init.text:spi_register_board_info from __ksymtab_gpl between '__ksymtab_spi_register_board_info' (at offset 0xc032f7d0) and '__ksymtab_spi_alloc_master'
Fix this by removing the export.
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a swsusp debugging mode. This does everything that's needed for a suspend
except for actually suspending. So we can look in the log messages and work
out a) what code is being slow and b) which drivers are misbehaving.
(1)
# echo testproc > /sys/power/disk
# echo disk > /sys/power/state
This should turn off the non-boot CPU, freeze all processes, wait for 5
seconds and then thaw the processes and the CPU.
(2)
# echo test > /sys/power/disk
# echo disk > /sys/power/state
This should turn off the non-boot CPU, freeze all processes, shrink
memory, suspend all devices, wait for 5 seconds, resume the devices etc.
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Stefan Seyfried <seife@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Apparently FUTEX_FD is unfixably racy and nothing uses it (or if it does, it
shouldn't).
Add a warning printk, give any remaining users six months to migrate off it.
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
printk_ratelimit() has global state which makes it not useful for callers
which wish to perform ratelimiting at a particular frequency.
Add a printk_timed_ratelimit() which utilises caller-provided state storage to
permit more flexibility.
This function can in fact be used for things other than printk ratelimiting
and is perhaps poorly named.
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It looks like there is a bug in init_reap_node() in slab.c that can cause
multiple oops's on certain ES7000 configurations. The variable reap_node
is defined per cpu, but only initialized on a single CPU. This causes an
oops in next_reap_node() when __get_cpu_var(reap_node) returns the wrong
value. Fix is below.
Signed-off-by: Dan Yeisley <dan.yeisley@unisys.com>
Cc: Andi Kleen <ak@suse.de>
Acked-by: Christoph Lameter <clameter@engr.sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Taken from http://bugzilla.kernel.org/show_bug.cgi?id=7439
It looks like device registration in drivers/char/ipmi/ipmi_si_intf.c was
cleaned up and a small error was made when setting the class_mask. The fix
is simple as the correct mask value is defined in the code but is not used.
Acked-by: Corey Minyard <minyard@acm.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When I was performing some operations on NFS, I got below error on server
side.
=============================================
[ INFO: possible recursive locking detected ]
2.6.19-prep #1
---------------------------------------------
nfsd4/3525 is trying to acquire lock:
(&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24
but task is already holding lock:
(&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24
other info that might help us debug this:
2 locks held by nfsd4/3525:
#0: (client_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24
#1: (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24
stack backtrace:
[<c04051ed>] show_trace_log_lvl+0x58/0x16a
[<c04057fa>] show_trace+0xd/0x10
[<c0405913>] dump_stack+0x19/0x1b
[<c043b6f1>] __lock_acquire+0x778/0x99c
[<c043be86>] lock_acquire+0x4b/0x6d
[<c0611ceb>] __mutex_lock_slowpath+0xbc/0x20a
[<c0611e5a>] mutex_lock+0x21/0x24
[<c047fd7e>] vfs_rmdir+0x76/0xf8
[<f94b7ce9>] nfsd4_clear_clid_dir+0x2c/0x41 [nfsd]
[<f94b7de9>] nfsd4_remove_clid_dir+0xb1/0xe8 [nfsd]
[<f94b307b>] laundromat_main+0x9b/0x1c3 [nfsd]
[<c04333d6>] run_workqueue+0x7a/0xbb
[<c0433d0b>] worker_thread+0xd2/0x107
[<c0436285>] kthread+0xc3/0xf2
[<c0402005>] kernel_thread_helper+0x5/0xb
===================================================================
Cause for this problem was,2 successive mutex_lock calls on 2 diffrent inodes ,as shown below
static int
nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
{
int status;
/* For now this directory should already be empty, but we empty it of
* any regular files anyway, just in case the directory was created by
* a kernel from the future.... */
nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file);
mutex_lock(&dir->d_inode->i_mutex);
status = vfs_rmdir(dir->d_inode, dentry);
...
int vfs_rmdir(struct inode *dir, struct dentry *dentry)
{
int error = may_delete(dir, dentry, 1);
if (error)
return error;
if (!dir->i_op || !dir->i_op->rmdir)
return -EPERM;
DQUOT_INIT(dir);
mutex_lock(&dentry->d_inode->i_mutex);
...
So I have developed the patch to overcome this problem.
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Call sysdev_class_unregister() on failure in edac_sysfs_memctrl_setup()
and decrease identation level for clear logic.
Acked-by: Doug Thompson <norsk5@xmission.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This just ignore the remaining pages, and remove unneeded unlock_pages().
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This just ignore the remaining pages.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This just ignore the remaining pages, and will fix a forgot put_pages_list().
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Current read_pages() assume ->readpages() frees the passed pages.
This patch free the pages in ->read_pages(), if those were remaining in the
pages_list. So, readpages() just can ignore the remaining pages in
pages_list.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix module_param/sysfs file permission typo.
Clean up MODULE_PARM_DESC strings to avoid fancy (and incorrect)
formatting.
Fix header includes for lkdtm; add some needed ones, remove unused ones;
and fix this gcc warning:
drivers/misc/lkdtm.c:150: warning: 'struct buffer_head' declared inside parameter list
drivers/misc/lkdtm.c:150: warning: its scope is only this definition or declaration, which is probably not what you want
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Ankita Garg <ankita@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ufs2 fails to mount on x86_64, claiming bad magic. This is because
ufs_super_block_third's fs_un1 member is padded out by 4 bytes for 8-byte
alignment, pushing down the rest of the struct.
Forcing this to be packed solves it. I took a quick look over other
on-disk structures and didn't immediately find other problems. I was able
to mount & ls a populated ufs2 filesystem w/ this change.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Un-needed add-store operation wastes a few bytes.
8 bytes wasted with -O2, on a ppc.
Signed-off-by: nkalmala <nkalmala@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix two issuses related to ipc_ids->entries freeing.
1. When freeing ipc namespace we need to free entries allocated
with ipc_init_ids().
2. When removing old entries in grow_ary() ipc_rcu_putref()
may be called on entries set to &ids->nullentry earlier in
ipc_init_ids().
This is almost impossible without namespaces, but with
them this situation becomes possible.
Found during OpenVZ testing after obvious leaks in beancounters.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move journal-api into filesystems.tmpl as a Chapter. Applies on top of the
previous docbook: make a filesystems book patch.
Remove trailing whitespace from journal-api chapter. Align some of the
tags.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Correct a few comments in kernel-doc Doc and source files.
(akpm: note: the patch removes a non-ascii character and might have to be
applied by hand..)
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
758333458a fixes the not checked copy_to_user
return value of compat_sys_pselect7. I ran into this too because of an old
source tree, but my fix would look quite a bit different to Andi's fix.
The reason is that the compat function IMHO should behave the very same as
the non-compat function if possible. Since sys_pselect7 does not return
-EFAULT in this specific case, change the compat code so it behaves like
sys_pselect7.
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This allows udev to do something intelligent when an array becomes
available.
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Neil's xterms are too wide.
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I missed a pointer dereference in this kmalloc result check.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] report rename failure when target file is locked by Windows
[CIFS] Allow null user connections
[CIFS] Fix readdir breakage when blocksize set too small
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
RDMA/addr: Use client registration to fix module unload race
IB/mthca: Fix MAD extended header format for MAD_IFC firmware command
IB/uverbs: Return sq_draining value in query_qp response
IB/amso1100: Fix incorrect pr_debug()
IB/amso1100: Use dma_alloc_coherent() instead of kmalloc/dma_map_single
IB/ehca: Fix eHCA driver compilation for uniprocessor
RDMA/cma: rdma_bind_addr() leaks a cma_dev reference count
IB/iser: Start connection after enabling iSER
Require registration with ib_addr module to prevent caller from
unloading while a callback is in progress.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Do not use -msym32 option for modules.
[MIPS] Don't use R10000 llsc workaround version for all llsc-full processors.
[MIPS] Ocelot G: Fix : "CURRENTLY_UNUSED" is not defined warning.
[MIPS] Fix warning about init_initrd() call if !CONFIG_BLK_DEV_INITRD.
[MIPS] IP27: Allow SMP ;-) Another changeset messed up by patch.
[MIPS] Fix merge screwup by patch(1)
Revert "[MIPS] Make SPARSEMEM selectable on QEMU."
On 64-bit kernel, modules are loaded into XKSEG for now. While XKSEG
address is not a sign-extended 32-bit address, we can not use -msym32
option.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/momentum/ocelot_g/gt-irq.o
arch/mips/momentum/ocelot_g/gt-irq.c:30:5: warning: "CURRENTLY_UNUSED" is not defined
arch/mips/momentum/ocelot_g/gt-irq.c:199:5: warning: "CURRENTLY_UNUSED" is not defined
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When lmo commit 4ef893e0515e8bf336dfbd200884f244869fbb43 was merged to
kernel.org as e73ea273ef patch happily
applied the IP27 segment to IP22. f63f36c18b11e166d0f362ac04dbcd7e6ea23f9e
did fix the effects partially - and with a wrong log message. Now fixed
for real (tm).
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patch happily applied an Ocelot G patch to Ocelot C when merging
linux-mips.org changeset 91ee9a801e65d2981dfe327d2519c7fc6ab02e6b into
kernel.org as 6ceb6d3ab2.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This reverts commit 31473747bd.
Another amazing example of patch(1) messing up - lmo changeset
66e8560d11d02bcadc261498471831a6375ad046 was merged twice to kernel.org
and ended up doing this rubbish job.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[NETFILTER]: silence a warning in ebtables
[IPV6]: File the fingerprints off ah6->spi/esp6->spi
[TCP]: Set default congestion control when no sysctl.
[TIPC] net/tipc/port.c: fix NULL dereference
Fixes Samba bugzilla bug # 4182
Rename by handle failures (retry after rename by path) were not
being returned back.
Signed-off-by: Steve French <sfrench@us.ibm.com>
This reverts commit f833229c96:
According to reviewers and the lspci data provided in commit message
itself, PCI ID 0x7110 should not have been added to ata_piix.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
net/bridge/netfilter/ebtables.c: In function 'ebt_dev_check':
net/bridge/netfilter/ebtables.c:89: warning: initialization discards qualifiers from pointer target type
So make the char* a const char * and the warning is gone.
Signed-off-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
I copied the logic from ll/sc arch implementations, but that
was wrong and makes no sense at all. Just do a straight
compare-exchange instruction, just like x86.
Based upon bug reports from Dennis Gilmore and Fabio Massimo.
Signed-off-by: David S. Miller <davem@davemloft.net>
In theory these are opaque 32bit values. However, we end up
allocating them sequentially in host-endian and stick unchanged
on the wire.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The setting of the default congestion control was buried in
the sysctl code so it would not be done properly if SYSCTL was
not enabled.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
