Give the statfs superblock operation a dentry pointer rather than a superblock
pointer.
This complements the get_sb() patch. That reduced the significance of
sb->s_root, allowing NFS to place a fake root there. However, NFS does
require a dentry to use as a target for the statfs operation. This permits
the root in the vfsmount to be used instead.
linux/mount.h has been added where necessary to make allyesconfig build
successfully.
Interest has also been expressed for use with the FUSE and XFS filesystems.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.
The filesystem is then required to manually set the superblock and root dentry
pointers. For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).
The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.
This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing. In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.
The patch also makes the following changes:
(*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
pointer argument and return an integer, so most filesystems have to change
very little.
(*) If one of the convenience function is not used, then get_sb() should
normally call simple_set_mnt() to instantiate the vfsmount. This will
always return 0, and so can be tail-called from get_sb().
(*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
dcache upon superblock destruction rather than shrink_dcache_anon().
This is required because the superblock may now have multiple trees that
aren't actually bound to s_root, but that still need to be cleaned up. The
currently called functions assume that the whole tree is rooted at s_root,
and that anonymous dentries are not the roots of trees which results in
dentries being left unculled.
However, with the way NFS superblock sharing are currently set to be
implemented, these assumptions are violated: the root of the filesystem is
simply a dummy dentry and inode (the real inode for '/' may well be
inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
with child trees.
[*] Anonymous until discovered from another tree.
(*) The documentation has been adjusted, including the additional bit of
changing ext2_* into foo_* in the documentation.
[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I have seen the cdrom drive appearing confused on using kdump on certain
x86_64 systems. During the booting up of the second kernel, the following
message would keep flooding the console, and the booting would not proceed
any further.
hda: cdrom_pc_intr: The drive appears confused (ireason = 0x01)
In this patch, whenever we are hitting a confused state in the interrupt
handler with the DRQ set, we end the request and return ide_stopped. Using
this I dont see the status error.
Signed-off-by: Rachita Kothiyal <rachita@in.ibm.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6:
[PATCH] Driver core: fix locking issues with the devices that are attached to classes
[PATCH] USB: get USB suspend to work again
Yeah, it's a hack, but it is only temporary until Alan's patches
reworking this area make it in. We really should not care what devices
below us are doing, especially when we do not really know what type of
devices they are. This patch relies on the fact that the endpoint
devices do not have a driver assigned to us.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (21 commits)
[ARM] 3629/1: S3C24XX: fix missing bracket in regs-dsc.h
[ARM] 3537/1: Rework DMA-bounce locking for finer granularity
[ARM] 3601/1: i.MX/MX1 DMA error handling for signaled channels only
[ARM] 3597/1: ixp4xx/nslu2: Board support for new LED subsystem
[ARM] 3595/1: ixp4xx/nas100d: Board support for new LED subsystem
[ARM] 3626/1: ARM EABI: fix syscall restarting
[ARM] 3628/1: S3C24XX: add get_rate call to struct clk
[ARM] 3627/1: S3C24XX: split s3c2410 clocks from core clocks
[ARM] 3613/1: S3C2410: Add sysdev and sysclass
[ARM] 3624/1: Report true modem control line states
[ARM] 3620/2: ixp23xx: add uengine loader support
[ARM] 3618/1: add defconfig for logicpd pxa270 card engine
[ARM] 3617/1: ep93xx: fix slightly incorrect timer tick rate
[ARM] 3616/1: fix timer handler wrap logic for a number of platforms
[ARM] 3615/1: ixp23xx: use platform devices for physmap flash
[ARM] 3614/1: ep93xx: use platform devices for physmap flash
[ARM] 3621/1: fix compilation breakage for pnx4008
[ARM] 3623/1: pnx4008: move GPIO-related defines to gpio.h
[ARM] 3622/1: pnx4008: remove clk_use/clk_unuse
[ARM] Enable VFP to be built when non-VFP capable CPUs are selected
...
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-serial:
[ARM] 3600/1: increase amba-pl010 UART_NR to 8
[ARM] 3571/1: netX: serial driver for Hilscher netX
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] Fix ondemand vs suspend deadlock
[CPUFREQ] Fix powernow-k8 SMP kernel on UP hardware bug.
[PATCH] redirect speedstep-centrino maintainer mail to cpufreq list
[CPUFREQ] correct powernow-k8 fid/vid masks for extended parts
[CPUFREQ] Clarify powernow-k8 cpu_family statements
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6: (33 commits)
[PATCH] myri10ge - drop workaround pci_save_state() disabling MSI
[PATCH] myri10ge - drop workaround for the missing AER ext cap on nVidia CK804
via-velocity: the link is not correctly detected when the device starts
[PATCH] add b44 to maintainers
[PATCH] WAN: ioremap() failure checks in drivers
[PATCH] WAN: register_hdlc_device() doesn't need dev_alloc_name()
[PATCH] skb_padto()-area fixes in 8390, wavelan
[PATCH] make drivers/net/forcedeth.c:nv_update_pause() static
[PATCH] network driver for Hilscher netx
[PATCH] Dereference in tokenring/olympic.c
[PATCH] Array overrun in drivers/net/wireless/wavelan.c
[PATCH] Remove useless check in drivers/net/pcmcia/xirc2ps_cs.c
[PATCH] 8139cp: add ethtool eeprom support
[PATCH] 8139cp: fix eeprom read command length
[PATCH] b44: update b44 Kconfig entry
[PATCH] b44: update version to 1.01
[PATCH] b44: add wol for old nic
[PATCH] b44: add parameter
[PATCH] b44: add wol
[PATCH] b44: fix manual speed/duplex/autoneg settings
...
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (139 commits)
[POWERPC] re-enable OProfile for iSeries, using timer interrupt
[POWERPC] support ibm,extended-*-frequency properties
[POWERPC] Extra sanity check in EEH code
[POWERPC] Dont look for class-code in pci children
[POWERPC] Fix mdelay badness on shared processor partitions
[POWERPC] disable floating point exceptions for init
[POWERPC] Unify ppc syscall tables
[POWERPC] mpic: add support for serial mode interrupts
[POWERPC] pseries: Print PCI slot location code on failure
[POWERPC] spufs: one more fix for 64k pages
[POWERPC] spufs: fail spu_create with invalid flags
[POWERPC] spufs: clear class2 interrupt status before wakeup
[POWERPC] spufs: fix Makefile for "make clean"
[POWERPC] spufs: remove stop_code from struct spu
[POWERPC] spufs: fix spu irq affinity setting
[POWERPC] spufs: further abstract priv1 register access
[POWERPC] spufs: split the Cell BE support into generic and platform dependant parts
[POWERPC] spufs: dont try to access SPE channel 1 count
[POWERPC] spufs: use kzalloc in create_spu
[POWERPC] spufs: fix initial state of wbox file
...
Manually resolved conflicts in:
drivers/net/phy/Makefile
include/asm-powerpc/spu.h
We don't need to restore the state right after saving it for later recovery
since commit 99dc804d9b (PCI: disable msi mode
in pci_disable_device) now prevents pci_save_state() from disabling MSI.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
We don't need to hardcode the AER capability of the nVidia CK804 chipset
anymore since commit cf34a8e07f (PCI: nVidia
quirk to make AER PCI-E extended capability visible) now makes sure that
this cap will be available to pci_find_ext_capability().
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Eric Sesterhenn found that pci200syn initialization lacks return
statement in ioremap() error path (coverity bug id #195). It looks
like more WAN drivers have problems with ioremap().
Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
David Boggs noticed that register_hdlc_device() no longer needs
to call dev_alloc_name() as it's called by register_netdev().
register_hdlc_device() is currently equivalent to register_netdev().
hdlc_setup() is now EXPORTed as per David's request.
Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Ar Iau, 2006-06-22 am 21:29 +1000, ysgrifennodd Herbert Xu:
> Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> >
> > The 8390 change (corrected version) also makes 8390.c faster so should
> > be applied anyway, and the orinoco one fixes some code that isn't even
> > needed and someone forgot to remove long ago. Otherwise the skb_padto
>
> Yeah I agree totally. However, I haven't actually seen the fixed 8390
> version being posted yet or at least not to netdev :)
Ah the resounding clang of a subtle hint ;)
Signed-off-by: Alan Cox <alan@redhat.com>
- Return 8390.c to the old way of handling short packets (which is also
faster)
- Remove the skb_padto from orinoco. This got left in when the padding bad
write patch was added and is actually not needed. This is fixing a merge
error way back when.
- Wavelan can also use the stack based buffer trick if you want
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch makes the needlessly global nv_update_pause() static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This is a patch for the Hilscher netx builtin ethernet ports. The
netx board support was merged into 2.6.17-git2.
The netx is a arm926 based SoC.
Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
--
drivers/net/Kconfig | 11
drivers/net/Makefile | 1
drivers/net/netx-eth.c | 516 ++++++++++++++++++++++++++++++++++++++++
include/asm-arm/arch-netx/eth.h | 27 ++
4 files changed, 555 insertions(+)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
hi,
coverity found (bug id #225) that we might call free_netdev()
with NULL argument, when alloc_trdev() fails. This patch
changes the goto, so we dont call free_netdev() for
dev == NULL.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
hi,
this is another array overrun spotted by coverity (#id 507)
we should check the index against array size before using it.
Not sure why the driver doesnt use ARRAY_SIZE instead of its
own macro.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
hi,
coverity choked at this check (id #223), assuming that
skb might be NULL and used anyways later. Since
start_hard_xmit() always gets called with a valid
skb, the check is useless and this patch removes it.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement the ethtool eeprom operations for the 8139cp driver.
Tested on x86 and big-endian ARM.
Signed-off-by: Philip Craig <philipc@snapgear.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The read command for the 93C46/93C56 EEPROMS should be 3 bits plus
the address. This doesn't appear to affect the operation of the
read command, but similar errors for write commands do cause failures.
Signed-off-by: Philip Craig <philipc@snapgear.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch adds wol support for the older 440x nics that use pattern matching.
This patch is a redo thanks to feedback from Michael Chan and Francois Romieu.
Signed-off-by: Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This patch adds a parameter to init_hw() to not completely initialize
the nic for wol.
Signed-off-by: Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Adds wol to the driver.
This is a redo of a previous patch thanks to feedback from Francois Romieu.
Signed-off-by Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fixes for speed/duplex/autoneg settings and driver settings info.
This is a redo of a previous patch thanks to feedback from Jeff Garzik.
Signed-off-by: Gary Zambrano <zambrano@broadcom.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Adds power-management (suspend/resume) support to the AT91RM9200
Ethernet driver.
Patch from David Brownell.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Moved global ether_clk variable into controller data structure.
Patch from David Brownell.
Davicom 9161 PHY was being incorrectly displayed as "9196".
Patch from Brian Stafford.
clk_get() doesn't return NULL on error, so the return value needs to be
tested with IS_ERR().
Whitespace cleanup.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Adds support for the MII ioctls via generic_mii_ioctl().
Patch from Brian Stafford.
Set the mii.phy_id to the detected PHY address, otherwise ethtool cannot
access PHYs other than 0.
Patch from Roman Kolesnikov.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
For Ethernet PHYs that don't have an IRQ pin or boards that don't
connect the IRQ pin to the processor, we enable a timer to poll the
PHY's link state.
Patch originally supplied by Eric Benard and Roman Kolesnikov.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
IOC3's homegrown DMA mapping functions that are used to optimize things
a little on IP27 set the wrong bit.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (27 commits)
[PATCH] PCI: nVidia quirk to make AER PCI-E extended capability visible
[PATCH] PCI: fix issues with extended conf space when MMCONFIG disabled because of e820
[PATCH] PCI: Bus Parity Status sysfs interface
[PATCH] PCI: fix memory leak in MMCONFIG error path
[PATCH] PCI: fix error with pci_get_device() call in the mpc85xx driver
[PATCH] PCI: MSI-K8T-Neo2-Fir: run only where needed
[PATCH] PCI: fix race with pci_walk_bus and pci_destroy_dev
[PATCH] PCI: clean up pci documentation to be more specific
[PATCH] PCI: remove unneeded msi code
[PATCH] PCI: don't move ioapics below PCI bridge
[PATCH] PCI: cleanup unused variable about msi driver
[PATCH] PCI: disable msi mode in pci_disable_device
[PATCH] PCI: Allow MSI to work on kexec kernel
[PATCH] PCI: AMD 8131 MSI quirk called too late, bus_flags not inherited ?
[PATCH] PCI: Move various PCI IDs to header file
[PATCH] PCI Bus Parity Status-broken hardware attribute, EDAC foundation
[PATCH] PCI: i386/x86_84: disable PCI resource decode on device disable
[PATCH] PCI ACPI: Rename the functions to avoid multiple instances.
[PATCH] PCI: don't enable device if already enabled
[PATCH] PCI: Add a "enable" sysfs attribute to the pci devices to allow userspace (Xorg) to enable devices without doing foul direct access
...
The AGP default doesn't work well with other selects, so use a select for
GART_IOMMU as well. Remove a redundant default for SWIOTLB as well.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Upgrade the zlib_inflate implementation in the kernel from a patched
version 1.1.3/4 to a patched 1.2.3.
The code in the kernel is about seven years old and I noticed that the
external zlib library's inflate performance was significantly faster (~50%)
than the code in the kernel on ARM (and faster again on x86_32).
For comparison the newer deflate code is 20% slower on ARM and 50% slower
on x86_32 but gives an approx 1% compression ratio improvement. I don't
consider this to be an improvement for kernel use so have no plans to
change the zlib_deflate code.
Various changes have been made to the zlib code in the kernel, the most
significant being the extra functions/flush option used by ppp_deflate.
This update reimplements the features PPP needs to ensure it continues to
work.
This code has been tested on ARM under both JFFS2 (with zlib compression
enabled) and ppp_deflate and on x86_32. JFFS2 sees an approx. 10% real
world file read speed improvement.
This patch also removes ZLIB_VERSION as it no longer has a correct value.
We don't need version checks anyway as the kernel's module handling will
take care of that for us. This removal is also more in keeping with the
zlib author's wishes (http://www.zlib.net/zlib_faq.html#faq24) and I've
added something to the zlib.h header to note its a modified version.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Joern Engel <joern@wh.fh-wedel.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
VGA_MAP_MEM translates to ioremap() on some architectures. It makes sense
to do this to vga_vram_base, because we're going to access memory between
vga_vram_base and vga_vram_end.
But it doesn't really make sense to map starting at vga_vram_end, because
we aren't going to access memory starting there. On ia64, which always has
to be different, ioremapping vga_vram_end gives you something completely
incompatible with ioremapped vga_vram_start, so vga_vram_size ends up being
nonsense.
As a bonus, we often know the size up front, so we can use ioremap()
correctly, rather than giving it a zero size.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- Add description of d_lock handling to comments over prune_one_dentry().
- It has three callsites - uninline it, saving 200 bytes of text.
Cc: Jan Blunck <jblunck@suse.de>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Olaf Hering <olh@suse.de>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The race is that the shrink_dcache_memory shrinker could get called while a
filesystem is being unmounted, and could try to prune a dentry belonging to
that filesystem.
If it does, then it will call in to iput on the inode while the dentry is
no longer able to be found by the umounting process. If iput takes a
while, generic_shutdown_super could get all the way though
shrink_dcache_parent and shrink_dcache_anon and invalidate_inodes without
ever waiting on this particular inode.
Eventually the superblock gets freed anyway and if the iput tried to touch
it (which some filesystems certainly do), it will lose. The promised
"Self-destruct in 5 seconds" doesn't lead to a nice day.
The race is closed by holding s_umount while calling prune_one_dentry on
someone else's dentry. As a down_read_trylock is used,
shrink_dcache_memory will no longer try to prune the dentry of a filesystem
that is being unmounted, and unmount will not be able to start until any
such active prune_one_dentry completes.
This requires that prune_dcache *knows* which filesystem (if any) it is
doing the prune on behalf of so that it can be careful of other
filesystems. shrink_dcache_memory isn't called it on behalf of any
filesystem, and so is careful of everything.
shrink_dcache_anon is now passed a super_block rather than the s_anon list
out of the superblock, so it can get the s_anon list itself, and can pass
the superblock down to prune_dcache.
If prune_dcache finds a dentry that it cannot free, it leaves it where it
is (at the tail of the list) and exits, on the assumption that some other
thread will be removing that dentry soon. To try to make sure that some
work gets done, a limited number of dnetries which are untouchable are
skipped over while choosing the dentry to work on.
I believe this race was first found by Kirill Korotaev.
Cc: Jan Blunck <jblunck@suse.de>
Acked-by: Kirill Korotaev <dev@openvz.org>
Cc: Olaf Hering <olh@suse.de>
Acked-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Avoid taking tasklist_lock for at getrusage for the multithreaded case too.
We don't need to take the tasklist lock for thread traversal of a process
since Oleg's do-__unhash_process-under-siglock.patch and related work.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the steal_locks() function.
steal_locks() doesn't work correctly with any filesystem that does it's own
lock management, including NFS, CIFS, etc.
In addition it has weird semantics on local filesystems in case tasks
sharing file-descriptor tables are doing POSIX locking operations in
parallel to execve().
The steal_locks() function has an effect on applications doing:
clone(CLONE_FILES)
/* in child */
lock
execve
lock
POSIX locks acquired before execve (by "child", "parent" or any further
task sharing files_struct) will after the execve be owned exclusively by
"child".
According to Chris Wright some LSB/LTP kind of suite triggers without the
stealing behavior, but there's no known real-world application that would
also fail.
Apps using NPTL are not affected, since all other threads are killed before
execve.
Apps using LinuxThreads are only affected if they
- have multiple threads during exec (LinuxThreads doesn't kill other
threads, the app may do it with pthread_kill_other_threads_np())
- rely on POSIX locks being inherited across exec
Both conditions are documented, but not their interaction.
Apps using clone() natively are affected if they
- use clone(CLONE_FILES)
- rely on POSIX locks being inherited across exec
The above scenarios are unlikely, but possible.
If the patch is vetoed, there's a plan B, that involves mostly keeping the
weird stealing semantics, but changing the way lock ownership is handled so
that network and local filesystems work consistently.
That would add more complexity though, so this solution seems to be
preferred by most people.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This race became a cause of oops, and can reproduce by the following.
while true; do
dd if=/dev/zero of=/dev/.static/dev/hdg1 bs=512 count=1000 & sync
done
This race condition was between __sync_single_inode() and iput().
cpu0 (fs's inode) cpu1 (bdev's inode)
----------------- -------------------
close("/dev/hda2")
[...]
__sync_single_inode()
/* copy the bdev's ->i_mapping */
mapping = inode->i_mapping;
generic_forget_inode()
bdev_clear_inode()
/* restre the fs's ->i_mapping */
inode->i_mapping = &inode->i_data;
/* bdev's inode was freed */
destroy_inode(inode);
if (wait) {
/* dereference a freed bdev's mapping->host */
filemap_fdatawait(mapping); /* Oops */
Since __sync_single_inode() is only taking a ref-count of fs's inode, the
another process can be close() and freeing the bdev's inode while writing
fs's inode. So, __sync_signle_inode() accesses the freed ->i_mapping,
oops.
This patch takes a ref-count on the bdev's inode for the fs's inode before
setting a ->i_mapping, and the clear_inode() of the fs's inode does iput() on
the bdev's inode. So if the fs's inode is still living, bdev's inode
shouldn't be freed.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
