Lee Schermerhorn noticed yesterday that I broke the mapping_writably_mapped
test in 2.6.7! Bad bad bug, good good find.
The i_mmap_writable count must be incremented for VM_SHARED (just as
i_writecount is for VM_DENYWRITE, but while holding the i_mmap_lock)
when dup_mmap() copies the vma for fork: it has its own more optimal
version of __vma_link_file(), and I missed this out. So the count
was later going down to 0 (dangerous) when one end unmapped, then
wrapping negative (inefficient) when the other end unmapped.
The only impact on x86 would have been that setting a mandatory lock on
a file which has at some time been opened O_RDWR and mapped MAP_SHARED
(but not necessarily PROT_WRITE) across a fork, might fail with -EAGAIN
when it should succeed, or succeed when it should fail.
But those architectures which rely on flush_dcache_page() to flush
userspace modifications back into the page before the kernel reads it,
may in some cases have skipped the flush after such a fork - though any
repetitive test will soon wrap the count negative, in which case it will
flush_dcache_page() unnecessarily.
Fix would be a two-liner, but mapping variable added, and comment moved.
Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The last patch to lib/idr.c caused a bug if idr_get_new_above() was
called on an empty idr.
Usually, nodes stay on the same layer. New layers are added to the top
of the tree.
The exception is idr_get_new_above() on an empty tree: In this case, the
new root node is first added on layer 0, then moved upwards. p->layer
was not updated.
As usual: You shall never rely on the source code comments, they will
only mislead you.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix __put_user_asm8() by jumping to the end label (3:) from the exception
handler, rather than jumping back to retry the second store instruction (label
2:).
Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the preemption resume_kernel() routine by inverting the test to see
whether interrupts are off (IM7 is all enabled, not all disabled).
Furthermore, interrupts should be disabled on entry to resume_kernel() so that
they're correctly set for jumping to restore_all() and doing the need
reschedule test.
Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Discard low-prioriy Tx interrupts when closing an MN10300 on-chip serial port.
The MN10300 on-chip serial port uses three interrupts to manage its serial
ports:
(1) A very high priority interrupt that drives virtual DMA for Rx.
(2) A very high priority interrupt that drives virtual DMA for Tx.
(3) A normal priority virtual interrupt that does the normal UART interrupt
stuff and is shared between Rx and Tx.
mn10300_serial_stop_tx() only disables the high priority Tx interrupt. It
doesn't also disable the normal priority one because it is shared with Rx.
However, the high priority interrupt may interrupt local_irq_disabled()
sections, and so may have queued up a low priority virtual interrupt whilst the
UART driver is asking for the Tx interrupt to be disabled.
The result of this can be an oops when we try to process the interrupt in
mn10300_serial_transmit_interrupt() as port->uart.info and port->uart.info->tty
may have gone away.
To deal with this, if either of those pointers is NULL, we make sure the
high-priority Tx interrupt is disabled and discard the interrupt. The low
priority interrupt is disabled by the mn10300_serial_pic irq_chip table.
Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Include the linux/page.h header into the MN10300 kernel linker script thus
allowing us to use PAGE_SIZE macro instead of a numeric constant.
Also use the PERCPU macro instead of an explicit section definition.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCIe: ASPM: Break out of endless loop waiting for PCI config bits to switch
PCI: stop leaking 'slot_name' in pci_create_slot
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] SN: prevent IRQ retargetting in request_irq()
[IA64] Fix section mismatch ioc3uart_init()/ioc3uart_submodule
[IA64] Clear up section mismatch for ioc4_ide_attach_one.
[IA64] Clear up section mismatch with arch_unregister_cpu()
[IA64] Clear up section mismatch for sn_check_wars.
[IA64] Updated the generic_defconfig to work with the 2.6.28-rc7 kernel.
[IA64] Fix GRU compile error w/o CONFIG_HUGETLB_PAGE
[IA64] eliminate NULL test and memset after alloc_bootmem
[IA64] remove BUILD_BUG_ON from paravirt_getreg()
The pktcdvd created class devices only export some sysfs files,
but have no char dev_t registered in the driver.
At class device creation time they copy the dev_t value of the
block device to the char device, wich will register a new char
device in the driver core and userspace, with a conflicting dev_t
value.
In many cases the class devices dev_t just points to a random
USB device. This fixes the sysfs "duplicate entry" errors.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Peter Osterlund <petero2@telia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sparc64:
drivers/video/mb862xx/mb862xxfb.c:929: warning: long long unsigned int format, resource_size_t arg (arg 4)
drivers/video/mb862xx/mb862xxfb.c:931: warning: long long unsigned int format, resource_size_t arg (arg 4)
We don't know what type the architecture uses to implement u64, hence they
cannot be printed.
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Matteo Fortini <m.fortini@selcomgroup.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miles Lane tailing /sys files hit a BUG which Pekka Enberg has tracked
to my 966c8c12dc sprint_symbol(): use
less stack exposing a bug in slub's list_locations() -
kallsyms_lookup() writes a 0 to namebuf[KSYM_NAME_LEN-1], but that was
beyond the end of page provided.
The 100 slop which list_locations() allows at end of page looks roughly
enough for all the other stuff it might print after the symbol before
it checks again: break out KSYM_SYMBOL_LEN earlier than before.
Latencytop and ftrace and are using KSYM_NAME_LEN buffers where they
need KSYM_SYMBOL_LEN buffers, and vmallocinfo a 2*KSYM_NAME_LEN buffer
where it wants a KSYM_SYMBOL_LEN buffer: fix those before anyone copies
them.
[akpm@linux-foundation.org: ftrace.h needs module.h]
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc Miles Lane <miles.lane@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On umount two event will be dispatched to watcher:
1: inotify_dev_queue_event(.., IN_UNMOUNT,..)
2: remove_watch(watch, dev)
->inotify_dev_queue_event(.., IN_IGNORED, ..)
But if watcher has IN_ONESHOT bit set then the watcher will be released
inside first event. Which result in accessing invalid object later. IMHO
it is not pure regression. This bug wasn't triggered while initial
inotify interface testing phase because of another bug in IN_ONESHOT
handling logic :)
commit ac74c00e49
Author: Ulisses Furquim <ulissesf@gmail.com>
Date: Fri Feb 8 04:18:16 2008 -0800
inotify: fix check for one-shot watches before destroying them
As the IN_ONESHOT bit is never set when an event is sent we must check it
in the watch's mask and not in the event's mask.
TESTCASE:
mkdir mnt
mount -ttmpfs none mnt
mkdir mnt/d
./inotify mnt/d&
umount mnt ## << lockup or crash here
TESTSOURCE:
/* gcc -oinotify inotify.c */
#include <stdio.h>
#include <stdlib.h>
#include <sys/inotify.h>
int main(int argc, char **argv)
{
char buf[1024];
struct inotify_event *ie;
char *p;
int i;
ssize_t l;
p = argv[1];
i = inotify_init();
inotify_add_watch(i, p, ~0);
l = read(i, buf, sizeof(buf));
printf("read %d bytes\n", l);
ie = (struct inotify_event *) buf;
printf("event mask: %d\n", ie->mask);
return 0;
}
Signed-off-by: Dmitri Monakhov <dmonakhov@openvz.org>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Robert Love <rlove@google.com>
Cc: Ulisses Furquim <ulissesf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 2f007e74bb, do_pages_stat()
gets the page address from user-space and puts the corresponding status
back while holding the mmap_sem for read. There is no need to hold
mmap_sem there while some page-faults may occur.
This patch adds a temporary address and status buffer so as to only
hold mmap_sem while working on these kernel buffers. This is
implemented by extracting do_pages_stat_array() out of do_pages_stat().
Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rusty Russell
Linus Torvalds
Hugh Dickins
Manfred Spraul
Akira Takeuchi
Cyrill Gorcunov
Kay Sievers
Andrew Morton
Dmitri Monakhov
Eric Dumazet
Brice Goglin
Balaji Rao
Matt Mackall