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2006-09-26[PATCH] PM: make it possible to disable console suspendingRafael J. Wysocki
Change suspend_console() so that it waits for all consoles to flush the remaining messages and make it possible to switch the console suspending off with the help of a Kconfig option. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: 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>
2006-09-26[PATCH] swsusp: Use memory bitmaps during resumeRafael J. Wysocki
Make swsusp use memory bitmaps to store its internal information during the resume phase of the suspend-resume cycle. If the pfns of saveable pages are saved during the suspend phase instead of the kernel virtual addresses of these pages, we can use them during the resume phase directly to set the corresponding bits in a memory bitmap. Then, this bitmap is used to mark the page frames corresponding to the pages that were saveable before the suspend (aka "unsafe" page frames). Next, we allocate as many page frames as needed to store the entire suspend image and make sure that there will be some extra free "safe" page frames for the list of PBEs constructed later. Subsequently, the image is loaded and, if possible, the data loaded from it are written into their "original" page frames (ie. the ones they had occupied before the suspend). The image data that cannot be written into their "original" page frames are loaded into "safe" page frames and their "original" kernel virtual addresses, as well as the addresses of the "safe" pages containing their copies, are stored in a list of PBEs. Finally, the list of PBEs is used to copy the remaining image data into their "original" page frames (this is done atomically, by the architecture-dependent parts of swsusp). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: Introduce memory bitmapsRafael J. Wysocki
Introduce the memory bitmap data structure and make swsusp use in the suspend phase. The current swsusp's internal data structure is not very efficient from the memory usage point of view, so it seems reasonable to replace it with a data structure that will require less memory, such as a pair of bitmaps. The idea is to use bitmaps that may be allocated as sets of individual pages, so that we can avoid making allocations of order greater than 0. For this reason the memory bitmap structure consists of several linked lists of objects that contain pointers to memory pages with the actual bitmap data. Still, for a typical system all of these lists fit in a single page, so it's reasonable to introduce an additional mechanism allowing us to allocate all of them efficiently without sacrificing the generality of the design. This is done with the help of the chain_allocator structure and associated functions. We need to use two memory bitmaps during the suspend phase of the suspend-resume cycle. One of them is necessary for marking the saveable pages, and the second is used to mark the pages in which to store the copies of them (aka image pages). First, the bitmaps are created and we allocate as many image pages as needed (the corresponding bits in the second bitmap are set as soon as the pages are allocated). Second, the bits corresponding to the saveable pages are set in the first bitmap and the saveable pages are copied to the image pages. Finally, the first bitmap is used to save the kernel virtual addresses of the saveable pages and the second one is used to save the contents of the image pages. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: Introduce some helpful constantsRafael J. Wysocki
Introduce some constants that hopefully will help improve the readability of code in kernel/power/snapshot.c. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Change the name of pagedir_nosaveRafael J. Wysocki
The name of the pagedir_nosave variable does not make sense any more, so it seems reasonable to change it to something more meaningful. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: Fix alloc_pagedirRafael J. Wysocki
Get rid of the FIXME in kernel/power/snapshot.c#alloc_pagedir() and simplify the functions called by it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: Reorder memory-allocating functionsRafael J. Wysocki
Move some functions in kernel/power/snapshot.c to a better place (in the same file) and introduce free_image_page() (will be necessary in the future). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: Fix mark_free_pagesRafael J. Wysocki
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing PageNosaveFree for PageNosave pages. This allows us to get rid of an ugly hack in kernel/power/snapshot.c#copy_data_pages(). Additionally, the page-copying loop in copy_data_pages() is moved to an inline function. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Disable CPU hotplug during suspendRafael J. Wysocki
The current suspend code has to be run on one CPU, so we use the CPU hotplug to take the non-boot CPUs offline on SMP machines. However, we should also make sure that these CPUs will not be enabled by someone else after we have disabled them. The functions disable_nonboot_cpus() and enable_nonboot_cpus() are moved to kernel/cpu.c, because they now refer to some stuff in there that should better be static. Also it's better if disable_nonboot_cpus() returns an error instead of panicking if something goes wrong, and enable_nonboot_cpus() has no reason to panic(), because the CPUs may have been enabled by the userland before it tries to take them online. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: struct snapshot_handle cleanupRafael J. Wysocki
Add comments describing struct snapshot_handle and its members, change the confusing name of its member 'page' to 'cur'. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: clean up browsing of pfnsRafael J. Wysocki
Clean up some loops over pfns for each zone in snapshot.c: reduce the number of additions to perform, rework detection of saveable pages and make the code a bit less difficult to understand, hopefully. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: read speedupAndrew Morton
Implement async reads for swsusp resuming. Crufty old PIII testbox: 15.7 MB/s -> 20.3 MB/s Sony Vaio: 14.6 MB/s -> 33.3 MB/s I didn't implement the post-resume bio_set_pages_dirty(). I don't really understand why resume needs to run set_page_dirty() against these pages. It might be a worry that this code modifies PG_Uptodate, PG_Error and PG_Locked against the image pages. Can this possibly affect the resumed-into kernel? Hopefully not, if we're atomically restoring its mem_map? Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Jens Axboe <axboe@suse.de> Cc: Laurent Riffard <laurent.riffard@free.fr> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: add read-speed instrumentationAndrew Morton
Add some instrumentation to the swsusp readin code to show what bandwidth we're achieving. Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: write speedupAndrew Morton
Switch the swsusp writeout code from 4k-at-a-time to 4MB-at-a-time. Crufty old PIII testbox: 12.9 MB/s -> 20.9 MB/s Sony Vaio: 14.7 MB/s -> 26.5 MB/s The implementation is crude. A better one would use larger BIOs, but wouldn't gain any performance. The memcpys will be mostly pipelined with the IO and basically come for free. The ENOMEM path has not been tested. It should be. Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] swsusp: add write-speed instrumentationAndrew Morton
Add some instrumentation to the swsusp writeout code to show what bandwidth we're achieving. Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] FRV: permit __do_IRQ() to be dispensed withDavid Howells
Permit __do_IRQ() to be dispensed with based on a configuration option. Signed-off-by: David Howells <dhowells@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] selinux: rename selinux_ctxid_to_stringStephen Smalley
Rename selinux_ctxid_to_string to selinux_sid_to_string to be consistent with other interfaces. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] selinux: eliminate selinux_task_ctxidStephen Smalley
Eliminate selinux_task_ctxid since it duplicates selinux_task_get_sid. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] NUMA: Add zone_to_nid functionChristoph Lameter
There are many places where we need to determine the node of a zone. Currently we use a difficult to read sequence of pointer dereferencing. Put that into an inline function and use throughout VM. Maybe we can find a way to optimize the lookup in the future. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] zone_reclaim: dynamic slab reclaimChristoph Lameter
Currently one can enable slab reclaim by setting an explicit option in /proc/sys/vm/zone_reclaim_mode. Slab reclaim is then used as a final option if the freeing of unmapped file backed pages is not enough to free enough pages to allow a local allocation. However, that means that the slab can grow excessively and that most memory of a node may be used by slabs. We have had a case where a machine with 46GB of memory was using 40-42GB for slab. Zone reclaim was effective in dealing with pagecache pages. However, slab reclaim was only done during global reclaim (which is a bit rare on NUMA systems). This patch implements slab reclaim during zone reclaim. Zone reclaim occurs if there is a danger of an off node allocation. At that point we 1. Shrink the per node page cache if the number of pagecache pages is more than min_unmapped_ratio percent of pages in a zone. 2. Shrink the slab cache if the number of the nodes reclaimable slab pages (patch depends on earlier one that implements that counter) are more than min_slab_ratio (a new /proc/sys/vm tunable). The shrinking of the slab cache is a bit problematic since it is not node specific. So we simply calculate what point in the slab we want to reach (current per node slab use minus the number of pages that neeed to be allocated) and then repeately run the global reclaim until that is unsuccessful or we have reached the limit. I hope we will have zone based slab reclaim at some point which will make that easier. The default for the min_slab_ratio is 5% Also remove the slab option from /proc/sys/vm/zone_reclaim_mode. [akpm@osdl.org: cleanups] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Profiling: require buffer allocation on the correct nodeChristoph Lameter
Profiling really suffers with off node buffers. Fail if no memory is available on the nodes. The profiling code can deal with these failures should they occur. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Add __GFP_THISNODE to avoid fallback to other nodes and ignore ↵Christoph Lameter
cpuset/memory policy restrictions Add a new gfp flag __GFP_THISNODE to avoid fallback to other nodes. This flag is essential if a kernel component requires memory to be located on a certain node. It will be needed for alloc_pages_node() to force allocation on the indicated node and for alloc_pages() to force allocation on the current node. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Fix longstanding load balancing bug in the schedulerChristoph Lameter
The scheduler will stop load balancing if the most busy processor contains processes pinned via processor affinity. The scheduler currently only does one search for busiest cpu. If it cannot pull any tasks away from the busiest cpu because they were pinned then the scheduler goes into a corner and sulks leaving the idle processors idle. F.e. If you have processor 0 busy running four tasks pinned via taskset, there are none on processor 1 and one just started two processes on processor 2 then the scheduler will not move one of the two processes away from processor 2. This patch fixes that issue by forcing the scheduler to come out of its corner and retrying the load balancing by considering other processors for load balancing. This patch was originally developed by John Hawkes and discussed at http://marc.theaimsgroup.com/?l=linux-kernel&m=113901368523205&w=2. I have removed extraneous material and gone back to equipping struct rq with the cpu the queue is associated with since this makes the patch much easier and it is likely that others in the future will have the same difficulty of figuring out which processor owns which runqueue. The overhead added through these patches is a single word on the stack if the kernel is configured to support 32 cpus or less (32 bit). For 32 bit environments the maximum number of cpus that can be configued is 255 which would result in the use of 32 bytes additional on the stack. On IA64 up to 1k cpus can be configured which will result in the use of 128 additional bytes on the stack. The maximum additional cache footprint is one cacheline. Typically memory use will be much less than a cacheline and the additional cpumask will be placed on the stack in a cacheline that already contains other local variable. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: John Hawkes <hawkes@sgi.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Williams <pwil3058@bigpond.net.au> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-25[PATCH] load_module: no BUG if module_subsys uninitializedEd Swierk
Invoking load_module() before param_sysfs_init() is called crashes in mod_sysfs_setup(), since the kset in module_subsys is not initialized yet. In my case, net-pf-1 is getting modprobed as a result of hotplug trying to create a UNIX socket. Calls to hotplug begin after the topology_init initcall. Another patch for the same symptom (module_subsys-initialize-earlier.patch) moves param_sysfs_init() to the subsys initcalls, but this is still not early enough in the boot process in some cases. In particular, topology_init() causes /sbin/hotplug to run, which requests net-pf-1 (the UNIX socket protocol) which can be compiled as a module. Moving param_sysfs_init() to the postcore initcalls fixes this particular race, but there might well be other cases where a usermodehelper causes a module to load earlier still. The patch makes load_module() return an error rather than crashing the kernel if invoked before module_subsys is initialized. Cc: Mark Huang <mlhuang@cs.princeton.edu> Cc: Greg KH <greg@kroah.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-22[NETLINK]: Extend netlink messaging interfaceThomas Graf
Adds: nlmsg_get_pos() return current position in message nlmsg_trim() trim part of message nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr nla_put_nohdr(skb, len, data) add attribute w/o hdr nla_find_nested() find attribute in nested attributes Fixes nlmsg_new() to take allocation flags and consider size. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-19[PATCH] genirq core: fix handle_level_irq()Ingo Molnar
while porting the -rt tree to 2.6.18-rc7 i noticed the following screaming-IRQ scenario on an SMP system: 2274 0Dn.:1 0.001ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.010ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.020ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.029ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.039ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.048ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.058ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.068ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.077ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.087ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.097ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) as it turns out, the bug is caused by handle_level_irq(), which if it races with another CPU already handling this IRQ, it _unmasks_ the IRQ line on the way out. This is not how 2.6.17 works, and we introduced this bug in one of the early genirq cleanups right before it went into -mm. (the bug was not in the genirq patchset for a long time, and we didnt notice the bug due to the lack of -rt rebase to the new genirq code. -rt, and hardirq-preemption in particular opens up such races much wider than anything else.) Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-16[PATCH] bug fix in kernel/kmod.cKenneth Lee
I think there is a bug in kmod.c: In __call_usermodehelper(), when kernel_thread(wait_for_helper, ...) return success, since wait_for_helper() might call complete() at any time, the sub_info should not be used any more. Normally wait_for_helper() take a long time to finish, you may not get problem for most of the case. But if you remove /sbin/modprobe, it may become easier for you to get a oop in khelper. Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-16[PATCH] genirq: fix typo in IRQ resendImre Deak
Fix a bug where the IRQ_PENDING flag is never cleared and the ISR is called endlessly without an actual interrupt. Signed-off-by: Imre Deak <imre.deak@solidboot.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-13[PATCH] rcu_do_batch: make ->qlen decrement irq safeOleg Nesterov
rcu_do_batch() decrements rdp->qlen with irqs enabled. This is not good, it can also be modified by call_rcu() from interrupt. Decrement ->qlen once with irqs disabled, after a main loop. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-13[PATCH] lockdep: double the number of stack-trace entriesIngo Molnar
Miles Lane reported the "BUG: MAX_STACK_TRACE_ENTRIES too low!" message, which means that during normal use his system produced enough lockdep events so that the 128-thousand entries stack-trace array got exhausted. Double the size of the array. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Miles Lane <miles.lane@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-11[PATCH] audit: AUDIT_PERM supportAl Viro
add support for AUDIT_PERM predicate Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-09-11[PATCH] update audit rule change messagesAmy Griffis
Make the audit message for implicit rule removal more informative. Make the rule update message consistent with other messages. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-09-11[PATCH] sanity check audit_bufferAmy Griffis
Add sanity checks for NULL audit_buffer consistent with other audit_log* routines. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-09-11[PATCH] fix ppid bug in 2.6.18 kernelSteve Grubb
Hello, During some troubleshooting, I found that ppid was accidentally omitted from the legacy rule section. This resulted in EINVAL for any rule with ppid sent with AUDIT_ADD. Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-09-08[PATCH] Use the correct restart option for futex_lock_piThomas Gleixner
The current implementation of futex_lock_pi returns -ERESTART_RESTARTBLOCK in case that the lock operation has been interrupted by a signal. This results in a return of -EINTR to userspace in case there is an handler for the signal. This is wrong, because userspace expects that the lock function does not return in any case of signal delivery. This was not caught by my insufficient test case, but triggered a nasty userspace problem in an high load application scenario. Unfortunately also glibc does not check for this invalid return value. Using -ERSTARTNOINTR makes sure, that the interrupted syscall is restarted. The restart block related code can be safely removed, as the possible timeout argument is an absolute time value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-06[PATCH] lockdep: do not touch console state when tainting the kernelIngo Molnar
Remove an unintended console_verbose() side-effect from add_taint(). Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-06[PATCH] prevent swsusp with PAEPavel Machek
PAE + swsusp results in hard-to-debug crash about 50% of time during resume. Cause is known, fix needs to be ported from x86-64 (but we can't make it to 2.6.18, and I'd like this to be worked around in 2.6.18). Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-06[PATCH] lockdep ifdef fixJarek Poplawski
With CONFIG_SMP=y CONFIG_PREEMPT=y CONFIG_LOCKDEP=y CONFIG_DEBUG_LOCK_ALLOC=y # CONFIG_PROVE_LOCKING is not set spin_unlock_irqrestore() goes through lockdep but spin_lock_irqsave() doesn't. Apparently, bad things happen. Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-02[PATCH] eligible_child: remove an obsolete ->tgid checkOleg Nesterov
It is not possible to find a sub-thread in ->children/->ptrace_children lists, ptrace_attach() does not allow to attach to sub-threads. Even if it was possible to ptrace the task from the same thread group, we can't allow to release ->group_leader while there are others (ptracer) threads in the same group. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01[PATCH] kerneldoc for handle_bad_irq()Henrik Kretzschmar
Adds the description of the parameters from handle_bad_irq(). Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01[PATCH] task delay accounting fixesShailabh Nagar
Cleanup allocation and freeing of tsk->delays used by delay accounting. This solves two problems reported for delay accounting: 1. oops in __delayacct_blkio_ticks http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1844.html Currently tsk->delays is getting freed too early in task exit which can cause a NULL tsk->delays to get accessed via reading of /proc/<tgid>/stats. The patch fixes this problem by freeing tsk->delays closer to when task_struct itself is freed up. As a result, it also eliminates the use of tsk->delays_lock which was only being used (inadequately) to safeguard access to tsk->delays while a task was exiting. 2. Possible memory leak in kernel/delayacct.c http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1389.html The patch cleans up tsk->delays allocations after a bad fork which was missing earlier. The patch has been tested to fix the problems listed above and stress tested with rapid calls to delay accounting's taskstats command interface (which is the other path that can access the same data, besides the /proc interface causing the oops above). Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] cpuset: oom panic fixNick Piggin
cpuset_excl_nodes_overlap always returns 0 if current is exiting. This caused customer's systems to panic in the OOM killer when processes were having trouble getting memory for the final put_user in mm_release. Even though there were lots of processes to kill. Change to returning 1 in this case. This achieves parity with !CONFIG_CPUSETS case, and was observed to fix the problem. Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] cpuset: top_cpuset tracks hotplug changes to cpu_online_mapPaul Jackson
Change the list of cpus allowed to tasks in the top (root) cpuset to dynamically track what cpus are online, using a CPU hotplug notifier. Make this top cpus file read-only. On systems that have cpusets configured in their kernel, but that aren't actively using cpusets (for some distros, this covers the majority of systems) all tasks end up in the top cpuset. If that system does support CPU hotplug, then these tasks cannot make use of CPUs that are added after system boot, because the CPUs are not allowed in the top cpuset. This is a surprising regression over earlier kernels that didn't have cpusets enabled. In order to keep the behaviour of cpusets consistent between systems actively making use of them and systems not using them, this patch changes the behaviour of the 'cpus' file in the top (root) cpuset, making it read only, and making it automatically track the value of cpu_online_map. Thus tasks in the top cpuset will have automatic use of hot plugged CPUs allowed by their cpuset. Thanks to Anton Blanchard and Nathan Lynch for reporting this problem, driving the fix, and earlier versions of this patch. Signed-off-by: Paul Jackson <pj@sgi.com> Cc: Nathan Lynch <ntl@pobox.com> Cc: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] Remove redundant up() in stop_machine()Yingchao Zhou
An up() is called in kernel/stop_machine.c on failure, and also in the caller (unconditionally). Signed-off-by: Zhou Yingchao <yingchao.zhou@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] futex_find_get_task(): remove an obscure EXIT_ZOMBIE checkOleg Nesterov
futex_find_get_task: if (p->state == EXIT_ZOMBIE || p->exit_state == EXIT_ZOMBIE) return NULL; I can't understand this. First, p->state can't be EXIT_ZOMBIE. The ->exit_state check looks strange too. Sub-threads or tasks whose ->parent ignores SIGCHLD go directly to EXIT_DEAD state (I am ignoring a ptrace case). Why EXIT_DEAD tasks should be ok? Yes, EXIT_ZOMBIE is more important (a task may stay zombie for a long time), but this doesn't mean we should explicitely ignore other EXIT_XXX states. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27[PATCH] revert "Drop tasklist lock in do_sched_setscheduler"Oleg Nesterov
sched_setscheduler() looks at ->signal->rlim[]. It is unsafe do dereference ->signal unless tasklist_lock or ->siglock is held (or p == current). We pin the task structure, but this can't prevent from release_task()->__exit_signal() which sets ->signal = NULL. Restore tasklist_lock across the setscheduler call. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-14[PATCH] workqueue: remove lock_cpu_hotplug()Andrew Morton
Use a private lock instead. It protects all per-cpu data structures in workqueue.c, including the workqueues list. Fix a bug in schedule_on_each_cpu(): it was forgetting to lock down the per-cpu resources. Unfixed long-standing bug: if someone unplugs the CPU identified by `singlethread_cpu' the kernel will get very sick. Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14[PATCH] futex_handle_fault always failsjohn stultz
We found this issue last week w/ the -RT kernel, but it seems the same issue is in mainline as well. Basically it is possible for futex_unlock_pi to return without actually freeing the lock. This is due to buggy logic in the use of futex_handle_fault() and its attempt argument in a failure case. Looking at futex.c the logic is as follows: 1) In futex_unlock_pi() we start w/ ret=0 and we go down to the first futex_atomic_cmpxchg_inatomic(), where we find uval==-EFAULT. We then jump to the pi_faulted label. 2) From pi_faulted: We increment attempt, unlock the sem and hit the retry label. 3) From the retry label, with ret still zero, we again hit EFAULT on the first futex_atomic_cmpxchg_inatomic(), and again goto the pi_faulted label. 4) Again from pi_faulted: we increment attempt and enter the conditional, where we call futex_handle_fault. 5) futex_handle_fault fails, and we goto the out_unlock_release_sem label. 6) From out_unlock_release_sem we return, and since ret is still zero, we return without error, while never actually unlocking the lock. Issue #1: at the first futex_atomic_cmpxchg_inatomic() we should probably be setting ret=-EFAULT before jumping to pi_faulted: However in our case this doesn't really affect anything, as the glibc we're using ignores the error value from futex_unlock_pi(). Issue #2: Look at futex_handle_fault(), its first conditional will return -EFAULT if attempt is >= 2. However, from the "if(attempt++) futex_handle_fault(attempt)" logic above, we'll *never* call futex_handle_fault when attempt is less then two. So we never get a chance to even try to fault the page in. The following patch addresses these two issues by 1) Always setting ret to -EFAULT if futex_handle_fault fails, and 2) Removing the = in futex_handle_fault's (attempt >= 2) check. I'm really not sure this is the right fix, but wanted to bring it up so folks knew the issue is alive and well in the current -git tree. From looking at the git logs the logic was first introduced (then later copied to other places) in the following commit almost a year ago: http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=4732efbeb997189d9f9b04708dc26bf8613ed721;hp=5b039e681b8c5f30aac9cc04385cc94be45d0823 Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14[PATCH] sys_getppid oopses on debug kernelKirill Korotaev
sys_getppid() optimization can access a freed memory. On kernels with DEBUG_SLAB turned ON, this results in Oops. As Dave Hansen noted, this optimization is also unsafe for memory hotplug. So this patch always takes the lock to be safe. [oleg@tv-sign.ru: simplifications] Signed-off-by: Kirill Korotaev <dev@openvz.org> Cc: <stable@kernel.org> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14[PATCH] panic.c build fixAndrew Morton
kernel/panic.c: In function 'add_taint': kernel/panic.c:176: warning: implicit declaration of function 'debug_locks_off' Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>