- 13 Jul, 2011 35 commits
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Greg Kroah-Hartman authored
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Miklos Szeredi authored
commit 2aa15890 upstream. Michael Leun reported that running parallel opens on a fuse filesystem can trigger a "kernel BUG at mm/truncate.c:475" Gurudas Pai reported the same bug on NFS. The reason is, unmap_mapping_range() is not prepared for more than one concurrent invocation per inode. For example: thread1: going through a big range, stops in the middle of a vma and stores the restart address in vm_truncate_count. thread2: comes in with a small (e.g. single page) unmap request on the same vma, somewhere before restart_address, finds that the vma was already unmapped up to the restart address and happily returns without doing anything. Another scenario would be two big unmap requests, both having to restart the unmapping and each one setting vm_truncate_count to its own value. This could go on forever without any of them being able to finish. Truncate and hole punching already serialize with i_mutex. Other callers of unmap_mapping_range() do not, and it's difficult to get i_mutex protection for all callers. In particular ->d_revalidate(), which calls invalidate_inode_pages2_range() in fuse, may be called with or without i_mutex. This patch adds a new mutex to 'struct address_space' to prevent running multiple concurrent unmap_mapping_range() on the same mapping. [ We'll hopefully get rid of all this with the upcoming mm preemptibility series by Peter Zijlstra, the "mm: Remove i_mmap_mutex lockbreak" patch in particular. But that is for 2.6.39 ] Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> Reported-by:
Michael Leun <lkml20101129@newton.leun.net> Reported-by:
Gurudas Pai <gurudas.pai@oracle.com> Tested-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@suse.de>
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Xufeng Zhang authored
[ Upstream commit 9cfaa8de ] Consider this scenario: When the size of the first received udp packet is bigger than the receive buffer, MSG_TRUNC bit is set in msg->msg_flags. However, if checksum error happens and this is a blocking socket, it will goto try_again loop to receive the next packet. But if the size of the next udp packet is smaller than receive buffer, MSG_TRUNC flag should not be set, but because MSG_TRUNC bit is not cleared in msg->msg_flags before receive the next packet, MSG_TRUNC is still set, which is wrong. Fix this problem by clearing MSG_TRUNC flag when starting over for a new packet. Signed-off-by:
Xufeng Zhang <xufeng.zhang@windriver.com> Signed-off-by:
Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Xufeng Zhang authored
[ Upstream commit 32c90254 ] udpv6_recvmsg() function is not using the correct variable to determine whether or not the socket is in non-blocking operation, this will lead to unexpected behavior when a UDP checksum error occurs. Consider a non-blocking udp receive scenario: when udpv6_recvmsg() is called by sock_common_recvmsg(), MSG_DONTWAIT bit of flags variable in udpv6_recvmsg() is cleared by "flags & ~MSG_DONTWAIT" in this call: err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); i.e. with udpv6_recvmsg() getting these values: int noblock = flags & MSG_DONTWAIT int flags = flags & ~MSG_DONTWAIT So, when udp checksum error occurs, the execution will go to csum_copy_err, and then the problem happens: csum_copy_err: ............... if (flags & MSG_DONTWAIT) return -EAGAIN; goto try_again; ............... But it will always go to try_again as MSG_DONTWAIT has been cleared from flags at call time -- only noblock contains the original value of MSG_DONTWAIT, so the test should be: if (noblock) return -EAGAIN; This is also consistent with what the ipv4/udp code does. Signed-off-by:
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Marcus Meissner authored
[ Upstream commit d0733d2e ] Check against mistakenly passing in IPv6 addresses (which would result in an INADDR_ANY bind) or similar incompatible sockaddrs. Signed-off-by:
Marcus Meissner <meissner@suse.de> Cc: Reinhard Max <max@suse.de> Signed-off-by:
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Eric Dumazet authored
[ Upstream commit 13fcb7bd ] In 2.6.27, commit 393e52e3 (packet: deliver VLAN TCI to userspace) added a small information leak. Add padding field and make sure its zeroed before copy to user. Signed-off-by:
Eric Dumazet <eric.dumazet@gmail.com> CC: Patrick McHardy <kaber@trash.net> Signed-off-by:
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Joe Perches authored
[ Upstream commit 6c4a5cb2 ] A mis-configured filter can spam the logs with lots of stack traces. Rate-limit the warnings and add printout of the bogus filter information. Original-patch-by:
Ben Greear <greearb@candelatech.com> Signed-off-by:
Joe Perches <joe@perches.com> Signed-off-by:
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Joe Perches authored
[ Upstream commit b3eec79b ] Add a generic mechanism to ratelimit WARN(foo, fmt, ...) messages using a hidden per call site static struct ratelimit_state. Also add an __WARN_RATELIMIT variant to be able to use a specific struct ratelimit_state. Signed-off-by:
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Rafael J. Wysocki authored
commit 4d4cf23c upstream. There is a bug in free_unnecessary_pages() that causes it to attempt to free too many pages in some cases, which triggers the BUG_ON() in memory_bm_clear_bit() for copy_bm. Namely, if count_data_pages() is initially greater than alloc_normal, we get to_free_normal equal to 0 and "save" greater from 0. In that case, if the sum of "save" and count_highmem_pages() is greater than alloc_highmem, we subtract a positive number from to_free_normal. Hence, since to_free_normal was 0 before the subtraction and is an unsigned int, the result is converted to a huge positive number that is used as the number of pages to free. Fix this bug by checking if to_free_normal is actually greater than or equal to the number we're going to subtract from it. Signed-off-by:
Rafael J. Wysocki <rjw@sisk.pl> Reported-and-tested-by:
Matthew Garrett <mjg@redhat.com> Signed-off-by:
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Rafael J. Wysocki authored
commit 6715045d upstream. There is a problem in hibernate_preallocate_memory() that it calls preallocate_image_memory() with an argument that may be greater than the total number of available non-highmem memory pages. If that's the case, the OOM condition is guaranteed to trigger, which in turn can cause significant slowdown to occur during hibernation. To avoid that, make preallocate_image_memory() adjust its argument before calling preallocate_image_pages(), so that the total number of saveable non-highem pages left is not less than the minimum size of a hibernation image. Change hibernate_preallocate_memory() to try to allocate from highmem if the number of pages allocated by preallocate_image_memory() is too low. Modify free_unnecessary_pages() to take all possible memory allocation patterns into account. Reported-by:
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by:
M. Vefa Bicakci <bicave@superonline.com> Signed-off-by:
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Eric Dumazet authored
[ Upstream commit eeb14972 ] A malicious user or buggy application can inject code and trigger an infinite loop in inet_diag_bc_audit() Also make sure each instruction is aligned on 4 bytes boundary, to avoid unaligned accesses. Reported-by:
Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by:
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Nelson Elhage authored
commit 6b8c92ba upstream. This will let us use it on a nlmsghdr stored inside a netlink_callback. Signed-off-by:
Nelson Elhage <nelhage@ksplice.com> Signed-off-by:
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Liu Aleaxander authored
commit fb967ecc upstream. The os-linux/mem.c file calls fchmod function, which is declared in sys/stat.h header file, so include it. Fixes build breakage under FC13. Signed-off-by:
Liu Aleaxander <Aleaxander@gmail.com> Acked-by:
Boaz Harrosh <bharrosh@panasas.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Roland McGrath authored
commit aa5fb4db upstream. With glibc 2.11 or later that was built with --enable-multi-arch, the UML link fails with undefined references to __rel_iplt_start and similar symbols. In recent binutils, the default linker script defines these symbols (see ld --verbose). Fix the UML linker scripts to match the new defaults for these sections. Signed-off-by:
Roland McGrath <roland@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Alan Stern authored
commit cbb33004 upstream. This patch (as1465) continues implementation of the policy that errors during suspend or hibernation should not prevent the system from going to sleep. In this case, failure to turn on the Suspend feature for a hub port shouldn't be reported as an error. There are situations where this does actually occur (such as when the device plugged into that port was disconnected in the recent past), and it turns out to be harmless. There's no reason for it to prevent a system sleep. Also, don't allow the hub driver to fail a system suspend if the downstream ports aren't all suspended. This is also harmless (and should never happen, given the change mentioned above); printing a warning message in the kernel log is all we really need to do. Signed-off-by:
Alan Stern <stern@rowland.harvard.edu> Signed-off-by:
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Alan Stern authored
commit 0af212ba upstream. This patch (as1464) implements the recommended policy that most errors during suspend or hibernation should not prevent the system from going to sleep. In particular, failure to suspend a USB driver or a USB device should not prevent the sleep from succeeding: Failure to suspend a device won't matter, because the device will automatically go into suspend mode when the USB bus stops carrying packets. (This might be less true for USB-3.0 devices, but let's not worry about them now.) Failure of a driver to suspend might lead to trouble later on when the system wakes up, but it isn't sufficient reason to prevent the system from going to sleep. Signed-off-by:
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Vasiliy Kulikov authored
commit 26c4caea upstream. Currently a single process may register exit handlers unlimited times. It may lead to a bloated listeners chain and very slow process terminations. Eg after 10KK sent TASKSTATS_CMD_ATTR_REGISTER_CPUMASKs ~300 Mb of kernel memory is stolen for the handlers chain and "time id" shows 2-7 seconds instead of normal 0.003. It makes it possible to exhaust all kernel memory and to eat much of CPU time by triggerring numerous exits on a single CPU. The patch limits the number of times a single process may register itself on a single CPU to one. One little issue is kept unfixed - as taskstats_exit() is called before exit_files() in do_exit(), the orphaned listener entry (if it was not explicitly deregistered) is kept until the next someone's exit() and implicit deregistration in send_cpu_listeners(). So, if a process registered itself as a listener exits and the next spawned process gets the same pid, it would inherit taskstats attributes. Signed-off-by:
Vasiliy Kulikov <segooon@gmail.com> Cc: Balbir Singh <bsingharora@gmail.com> Signed-off-by:
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Arnd Bergmann authored
commit 6e4e2f81 upstream. Lockdep found a locking inconsistency in the mkiss_close function: > kernel: [ INFO: inconsistent lock state ] > kernel: 2.6.39.1 #3 > kernel: --------------------------------- > kernel: inconsistent {IN-SOFTIRQ-R} -> {SOFTIRQ-ON-W} usage. > kernel: ax25ipd/2813 [HC0[0]:SC0[0]:HE1:SE1] takes: > kernel: (disc_data_lock){+++?.-}, at: [<ffffffffa018552b>] mkiss_close+0x1b/0x90 [mkiss] > kernel: {IN-SOFTIRQ-R} state was registered at: The message hints that disc_data_lock is aquired with softirqs disabled, but does not itself disable softirqs, which can in rare circumstances lead to a deadlock. The same problem is present in the 6pack driver, this patch fixes both by using write_lock_bh instead of write_lock. Reported-by:
Bernard F6BVP <f6bvp@free.fr> Tested-by:
Arnd Bergmann <arnd@arndb.de> Acked-by: Ralf Baechle<ralf@linux-mips.org> Signed-off-by:
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Trond Myklebust authored
commit 5afa9133 upstream. Fix a couple of instances where we were exiting the RPC client on arbitrary signals. We should only do so on fatal signals. Signed-off-by:
Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by:
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NeilBrown authored
commit 4274215d upstream. If a device fails in a way that causes pending request to take a while to complete, md will not be able to immediately remove it from the array in remove_and_add_spares. It will then incorrectly look like a spare device and md will try to recover it even though it is failed. This leads to a recovery process starting and instantly aborting over and over again. We should check if the device is faulty before considering it to be a spare. This will avoid trying to start a recovery that cannot proceed. This bug was introduced in 2.6.26 so that patch is suitable for any kernel since then. Reported-by:
Jim Paradis <james.paradis@stratus.com> Signed-off-by:
NeilBrown <neilb@suse.de> Signed-off-by:
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Jean Delvare authored
commit 9b640f2e upstream. * Print all error and information messages even when debugging is disabled. * Don't use adapter device to log messages before it is ready. Signed-off-by:
Jean Delvare <khali@linux-fr.org> Signed-off-by:
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Shaohua Li authored
commit 3181faa8 upstream. I got a rcu warnning at boot. the ioc->ioc_data is rcu_deferenced, but doesn't hold rcu_read_lock. Signed-off-by:
Shaohua Li <shaohua.li@intel.com> Signed-off-by:
Jens Axboe <jaxboe@fusionio.com> Signed-off-by:
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Jens Axboe authored
commit ab4bd22d upstream. Since we are modifying this RCU pointer, we need to hold the lock protecting it around it. This fixes a potential reuse and double free of a cfq io_context structure. The bug has been in CFQ for a long time, it hit very few people but those it did hit seemed to see it a lot. Tracked in RH bugzilla here: https://bugzilla.redhat.com/show_bug.cgi?id=577968 Credit goes to Paul Bolle for figuring out that the issue was around the one-hit ioc->ioc_data cache. Thanks to his hard work the issue is now fixed. Signed-off-by:
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Marcin Slusarz authored
commit 161b6ae0 upstream. Order of initialization look like this: ... debugobjects kmemleak ...(lots of other subsystems)... workqueues (through early initcall) ... debugobjects use schedule_work for batch freeing of its data and kmemleak heavily use debugobjects, so when it comes to freeing and workqueues were not initialized yet, kernel crashes: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff810854d1>] __queue_work+0x29/0x41a [<ffffffff81085910>] queue_work_on+0x16/0x1d [<ffffffff81085abc>] queue_work+0x29/0x55 [<ffffffff81085afb>] schedule_work+0x13/0x15 [<ffffffff81242de1>] free_object+0x90/0x95 [<ffffffff81242f6d>] debug_check_no_obj_freed+0x187/0x1d3 [<ffffffff814b6504>] ? _raw_spin_unlock_irqrestore+0x30/0x4d [<ffffffff8110bd14>] ? free_object_rcu+0x68/0x6d [<ffffffff8110890c>] kmem_cache_free+0x64/0x12c [<ffffffff8110bd14>] free_object_rcu+0x68/0x6d [<ffffffff810b58bc>] __rcu_process_callbacks+0x1b6/0x2d9 ... because system_wq is NULL. Fix it by checking if workqueues susbystem was initialized before using. Signed-off-by:
Marcin Slusarz <marcin.slusarz@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20110528112342.GA3068@joi.lanSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Florian Fainelli authored
commit 9b19d40a upstream. Otherwise, the gpiolib autorequest feature will produce a WARN_ON(): WARNING: at drivers/gpio/gpiolib.c:101 0x8020ec6c() autorequest GPIO-215 [...] Signed-off-by:
Florian Fainelli <florian@openwrt.org> Signed-off-by:
Wim Van Sebroeck <wim@iguana.be> Signed-off-by:
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Sjoerd Simons authored
commit 8ca2c80b upstream. When freeing memory for the video buffers also remove them from the irq & main queues. This fixes an oops when doing the following: open ("/dev/video", ..) VIDIOC_REQBUFS VIDIOC_QBUF VIDIOC_REQBUFS close () As the second VIDIOC_REQBUFS will cause the list entries of the buffers to be cleared while they still hang around on the main and irc queues Signed-off-by:
Sjoerd Simons <sjoerd.simons@collabora.co.uk> Acked-by:
Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by:
Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by:
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Rafael Aquini authored
commit b0320c7b upstream. When 1GB hugepages are allocated on a system, free(1) reports less available memory than what really is installed in the box. Also, if the total size of hugepages allocated on a system is over half of the total memory size, CommitLimit becomes a negative number. The problem is that gigantic hugepages (order > MAX_ORDER) can only be allocated at boot with bootmem, thus its frames are not accounted to 'totalram_pages'. However, they are accounted to hugetlb_total_pages() What happens to turn CommitLimit into a negative number is this calculation, in fs/proc/meminfo.c: allowed = ((totalram_pages - hugetlb_total_pages()) * sysctl_overcommit_ratio / 100) + total_swap_pages; A similar calculation occurs in __vm_enough_memory() in mm/mmap.c. Also, every vm statistic which depends on 'totalram_pages' will render confusing values, as if system were 'missing' some part of its memory. Impact of this bug: When gigantic hugepages are allocated and sysctl_overcommit_memory == OVERCOMMIT_NEVER. In a such situation, __vm_enough_memory() goes through the mentioned 'allowed' calculation and might end up mistakenly returning -ENOMEM, thus forcing the system to start reclaiming pages earlier than it would be ususal, and this could cause detrimental impact to overall system's performance, depending on the workload. Besides the aforementioned scenario, I can only think of this causing annoyances with memory reports from /proc/meminfo and free(1). [akpm@linux-foundation.org: standardize comment layout] Reported-by:
Russ Anderson <rja@sgi.com> Signed-off-by:
Rafael Aquini <aquini@linux.com> Acked-by:
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Eugene A. Shatokhin authored
commit a0b8de35 upstream. We would free the proper number of curves, but in the wrong slots, due to a missing level of indirection through the pdgain_idx table. It's simpler just to try to free all four slots, so do that. Signed-off-by:
Bob Copeland <me@bobcopeland.com> Signed-off-by:
John W. Linville <linville@tuxdriver.com> Signed-off-by:
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Michal Kubecek authored
commit 8440f4b1 upstream. When opening /dev/snapshot device, snapshot_open() creates memory bitmaps which are freed in snapshot_release(). But if any of the callbacks called by pm_notifier_call_chain() returns NOTIFY_BAD, open() fails, snapshot_release() is never called and bitmaps are not freed. Next attempt to open /dev/snapshot then triggers BUG_ON() check in create_basic_memory_bitmaps(). This happens e.g. when vmwatchdog module is active on s390x. Signed-off-by:
Michal Kubecek <mkubecek@suse.cz> Signed-off-by:
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Sarah Sharp authored
commit fa75ac37 upstream. While trying to switch a UAS device from the BOT configuration to the UAS configuration via the bConfigurationValue file, Tanya ran into an issue in the USB core. usb_disable_device() sets entries in udev->ep_out and udev->ep_out to NULL, but doesn't call into the xHCI bandwidth management functions to remove the BOT configuration endpoints from the xHCI host's internal structures. The USB core would then attempt to add endpoints for the UAS configuration, and some of the endpoints had the same address as endpoints in the BOT configuration. The xHCI driver blindly added the endpoints again, but the xHCI host controller rejected the Configure Endpoint command because active endpoints were added without being dropped. Make the xHCI driver reject calls to xhci_add_endpoint() that attempt to add active endpoints without first calling xhci_drop_endpoint(). This should be backported to kernels as old as 2.6.31. Signed-off-by:
Sarah Sharp <sarah.a.sharp@linux.intel.com> Reported-by:
Tanya Brokhman <tlinder@codeaurora.org> Signed-off-by:
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Jiri Slaby authored
commit 92f6fa09 upstream. We restored tty_ldisc_wait_idle in 100eeae2 (TTY: restore tty_ldisc_wait_idle). We used it in the ldisc changing path to fix the case where there are tasks in n_tty_read waiting for data and somebody tries to change ldisc. Similar to the case above, there may be also tasks waiting in n_tty_read while hangup is performed. As 65b77046 (tty-ldisc: turn ldisc user count into a proper refcount) removed the wait-until-idle from all paths, hangup path won't wait for them to disappear either now. So add it back even to the hangup path. There is a difference, we need uninterruptible sleep as there is obviously HUP signal pending. So tty_ldisc_wait_idle now sleeps without possibility to be interrupted. This is what original tty_ldisc_wait_idle did. After the wait idle reintroduction (100eeae2), we have had interruptible sleeps for the ldisc changing path. But as there is a 5s timeout anyway, we don't allow it to be interrupted from now on. It's not worth the added complexity of deciding what kind of sleep we want. Before 65b77046 tty_ldisc_release was called also from tty_ldisc_release. It is called from tty_release, so I don't think we need to restore that one. This is nicely reproducible after constifying the timing when drivers/tty/n_tty.c is patched as follows ("TTY: ntty, add one more sanity check" patch is needed to actually see it explode): %% -1548,6 +1549,7 @@ static int n_tty_open(struct tty_struct *tty) /* These are ugly. Currently a malloc failure here can panic */ if (!tty->read_buf) { + msleep(100); tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL); if (!tty->read_buf) return -ENOMEM; %% -1785,6 +1788,7 @@ do_it_again: break; } timeout = schedule_timeout(timeout); + msleep(20); continue; } __set_current_state(TASK_RUNNING); ===== With a process: ===== while (1) { int fd = open(argv[1], O_RDWR); read(fd, buf, sizeof(buf)); close(fd); } ===== and its child: ===== setsid(); while (1) { int fd = open(tty, O_RDWR|O_NOCTTY); ioctl(fd, TIOCSCTTY, 1); vhangup(); close(fd); usleep(100 * (10 + random() % 1000)); } ===== EOF ===== References: https://bugzilla.novell.com/show_bug.cgi?id=693374 References: https://bugzilla.novell.com/show_bug.cgi?id=694509Signed-off-by:
Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Thomas Gleixner authored
commit b5199515 upstream. The clocksource watchdog code is interruptible and it has been observed that this can trigger false positives which disable the TSC. The reason is that an interrupt storm or a long running interrupt handler between the read of the watchdog source and the read of the TSC brings the two far enough apart that the delta is larger than the unstable treshold. Move both reads into a short interrupt disabled region to avoid that. Reported-and-tested-by:
Vernon Mauery <vernux@us.ibm.com> Signed-off-by:
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Stefano Stabellini authored
commit a91d9287 upstream. We only need to set max_pfn_mapped to the last pfn mapped on x86_64 to make sure that cleanup_highmap doesn't remove important mappings at _end. We don't need to do this on x86_32 because cleanup_highmap is not called on x86_32. Besides lowering max_pfn_mapped on x86_32 has the unwanted side effect of limiting the amount of memory available for the 1:1 kernel pagetable allocation. This patch reverts the x86_32 part of the original patch. Signed-off-by:
Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by:
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by:
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Andrea Arcangeli authored
commit 99a15e21 upstream. swapcache will reach the below code path in migrate_page_move_mapping, and swapcache is accounted as NR_FILE_PAGES but it's not accounted as NR_SHMEM. Hugh pointed out we must use PageSwapCache instead of comparing mapping to &swapper_space, to avoid build failure with CONFIG_SWAP=n. Signed-off-by:
Andrea Arcangeli <aarcange@redhat.com> Acked-by:
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Hugh Dickins authored
commit 2b472611 upstream. Andrea Righi reported a case where an exiting task can race against ksmd::scan_get_next_rmap_item (http://lkml.org/lkml/2011/6/1/742) easily triggering a NULL pointer dereference in ksmd. ksm_scan.mm_slot == &ksm_mm_head with only one registered mm CPU 1 (__ksm_exit) CPU 2 (scan_get_next_rmap_item) list_empty() is false lock slot == &ksm_mm_head list_del(slot->mm_list) (list now empty) unlock lock slot = list_entry(slot->mm_list.next) (list is empty, so slot is still ksm_mm_head) unlock slot->mm == NULL ... Oops Close this race by revalidating that the new slot is not simply the list head again. Andrea's test case: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/mman.h> #define BUFSIZE getpagesize() int main(int argc, char **argv) { void *ptr; if (posix_memalign(&ptr, getpagesize(), BUFSIZE) < 0) { perror("posix_memalign"); exit(1); } if (madvise(ptr, BUFSIZE, MADV_MERGEABLE) < 0) { perror("madvise"); exit(1); } *(char *)NULL = 0; return 0; } Reported-by:
Andrea Righi <andrea@betterlinux.com> Tested-by:
Chris Wright <chrisw@sous-sol.org> Signed-off-by:
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- 23 Jun, 2011 5 commits
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Greg Kroah-Hartman authored
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Greg Kroah-Hartman authored
This reverts commit 6f63415f. It turns out this is not what we want to have happen for the .32 and .33-longterm kernels as it does not work properly at all. This was reported by Gentoo, Arch, and Canonical developers as causing problems for their users: https://bugs.archlinux.org/task/24302 http://bugs.gentoo.org/show_bug.cgi?id=359445 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/796336 Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Gordon Malm <gengor@gentoo.org> Cc: Don Fry <donald.h.fry@intel.com> Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by:
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Kasper Pedersen authored
commit a386b5af upstream. When the clocksource is not a multiple of HZ, the clock will be off. For acpi_pm, HZ=1000 the error is 127.111 ppm: The rounding of cycle_interval ends up generating a false error term in ntp_error accumulation since xtime_interval is not exactly 1/HZ. So, we subtract out the error caused by the rounding. This has been visible since 2.6.32-rc2 commit a092ff0f time: Implement logarithmic time accumulation That commit raised NTP_INTERVAL_FREQ and exposed the rounding error. testing tool: http://n1.taur.dk/permanent/testpmt.c Also tested with ntpd and a frequency counter. Signed-off-by:
Kasper Pedersen <kkp2010@kasperkp.dk> Acked-by:
john stultz <johnstul@us.ibm.com> Cc: John Kacur <jkacur@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:
Will Tisdale <willtisdale@gmail.com> Signed-off-by:
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Thomas Gleixner authored
commit 676dc3cf upstream. Mark the IRQF_NO_SUSPEND interrupts IRQF_FORCE_RESUME and remove the extra walk through the interrupt descriptors. Signed-off-by:
Stefan Bader <stefan.bader@canonical.com> Signed-off-by:
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Thomas Gleixner authored
commit dc5f219e upstream. Xen needs to reenable interrupts which are marked IRQF_NO_SUSPEND in the resume path. Add a flag to force the reenabling in the resume code. Tested-and-acked-by:
Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by:
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