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* mm: allow PF_MEMALLOC from softirq contextMel Gorman2012-07-311-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is needed to allow network softirq packet processing to make use of PF_MEMALLOC. Currently softirq context cannot use PF_MEMALLOC due to it not being associated with a task, and therefore not having task flags to fiddle with - thus the gfp to alloc flag mapping ignores the task flags when in interrupts (hard or soft) context. Allowing softirqs to make use of PF_MEMALLOC therefore requires some trickery. This patch borrows the task flags from whatever process happens to be preempted by the softirq. It then modifies the gfp to alloc flags mapping to not exclude task flags in softirq context, and modify the softirq code to save, clear and restore the PF_MEMALLOC flag. The save and clear, ensures the preempted task's PF_MEMALLOC flag doesn't leak into the softirq. The restore ensures a softirq's PF_MEMALLOC flag cannot leak back into the preempted process. This should be safe due to the following reasons Softirqs can run on multiple CPUs sure but the same task should not be executing the same softirq code. Neither should the softirq handler be preempted by any other softirq handler so the flags should not leak to an unrelated softirq. Softirqs re-enable hardware interrupts in __do_softirq() so can be preempted by hardware interrupts so PF_MEMALLOC is inherited by the hard IRQ. However, this is similar to a process in reclaim being preempted by a hardirq. While PF_MEMALLOC is set, gfp_to_alloc_flags() distinguishes between hard and soft irqs and avoids giving a hardirq the ALLOC_NO_WATERMARKS flag. If the softirq is deferred to ksoftirq then its flags may be used instead of a normal tasks but as the softirq cannot be preempted, the PF_MEMALLOC flag does not leak to other code by accident. [davem@davemloft.net: Document why PF_MEMALLOC is safe] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Neil Brown <neilb@suse.de> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Eric B Munson <emunson@mgebm.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Mel Gorman <mgorman@suse.de> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/hotplug: correctly setup fallback zonelists when creating new pgdatJiang Liu2012-07-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When hotadd_new_pgdat() is called to create new pgdat for a new node, a fallback zonelist should be created for the new node. There's code to try to achieve that in hotadd_new_pgdat() as below: /* * The node we allocated has no zone fallback lists. For avoiding * to access not-initialized zonelist, build here. */ mutex_lock(&zonelists_mutex); build_all_zonelists(pgdat, NULL); mutex_unlock(&zonelists_mutex); But it doesn't work as expected. When hotadd_new_pgdat() is called, the new node is still in offline state because node_set_online(nid) hasn't been called yet. And build_all_zonelists() only builds zonelists for online nodes as: for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); build_zonelist_cache(pgdat); } Though we hope to create zonelist for the new pgdat, but it doesn't. So add a new parameter "pgdat" the build_all_zonelists() to build pgdat for the new pgdat too. Signed-off-by: Jiang Liu <liuj97@gmail.com> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memcg: rename config variablesAndrew Morton2012-07-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | Sanity: CONFIG_CGROUP_MEM_RES_CTLR -> CONFIG_MEMCG CONFIG_CGROUP_MEM_RES_CTLR_SWAP -> CONFIG_MEMCG_SWAP CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED -> CONFIG_MEMCG_SWAP_ENABLED CONFIG_CGROUP_MEM_RES_CTLR_KMEM -> CONFIG_MEMCG_KMEM [mhocko@suse.cz: fix missed bits] Cc: Glauber Costa <glommer@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threadsWanpeng Li2012-07-312-6/+4
| | | | | | | | | | | | | | Since per-BDI flusher threads were introduced in 2.6, the pdflush mechanism is not used any more. But the old interface exported through /proc/sys/vm/nr_pdflush_threads still exists and is obviously useless. For back-compatibility, printk warning information and return 2 to notify the users that the interface is removed. Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: account the total_vm in the vm_stat_account()Huang Shijie2012-07-311-3/+1
| | | | | | | | | | | | vm_stat_account() accounts the shared_vm, stack_vm and reserved_vm now. But we can also account for total_vm in the vm_stat_account() which makes the code tidy. Even for mprotect_fixup(), we can get the right result in the end. Signed-off-by: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* resource: make sure requested range is included in the root rangeOctavian Purdila2012-07-301-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the requested range is outside of the root range the logic in __reserve_region_with_split will cause an infinite recursion which will overflow the stack as seen in the warning bellow. This particular stack overflow was caused by requesting the (100000000-107ffffff) range while the root range was (0-ffffffff). In this case __request_resource would return the whole root range as conflict range (i.e. 0-ffffffff). Then, the logic in __reserve_region_with_split would continue the recursion requesting the new range as (conflict->end+1, end) which incidentally in this case equals the originally requested range. This patch aborts looking for an usable range when the request does not intersect with the root range. When the request partially overlaps with the root range, it ajust the request to fall in the root range and then continues with the new request. When the request is modified or aborted errors and a stack trace are logged to allow catching the errors in the upper layers. [ 5.968374] WARNING: at kernel/sched.c:4129 sub_preempt_count+0x63/0x89() [ 5.975150] Modules linked in: [ 5.978184] Pid: 1, comm: swapper Not tainted 3.0.22-mid27-00004-gb72c817 #46 [ 5.985324] Call Trace: [ 5.987759] [<c1039dfc>] ? console_unlock+0x17b/0x18d [ 5.992891] [<c1039620>] warn_slowpath_common+0x48/0x5d [ 5.998194] [<c1031758>] ? sub_preempt_count+0x63/0x89 [ 6.003412] [<c1039644>] warn_slowpath_null+0xf/0x13 [ 6.008453] [<c1031758>] sub_preempt_count+0x63/0x89 [ 6.013499] [<c14d60c4>] _raw_spin_unlock+0x27/0x3f [ 6.018453] [<c10c6349>] add_partial+0x36/0x3b [ 6.022973] [<c10c7c0a>] deactivate_slab+0x96/0xb4 [ 6.027842] [<c14cf9d9>] __slab_alloc.isra.54.constprop.63+0x204/0x241 [ 6.034456] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.039842] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.045232] [<c10c7dc9>] kmem_cache_alloc_trace+0x51/0xb0 [ 6.050710] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.056100] [<c103f78f>] kzalloc.constprop.5+0x29/0x38 [ 6.061320] [<c17b45e9>] __reserve_region_with_split+0x1c/0xd1 [ 6.067230] [<c17b4693>] __reserve_region_with_split+0xc6/0xd1 ... [ 7.179057] [<c17b4693>] __reserve_region_with_split+0xc6/0xd1 [ 7.184970] [<c17b4779>] reserve_region_with_split+0x30/0x42 [ 7.190709] [<c17a8ebf>] e820_reserve_resources_late+0xd1/0xe9 [ 7.196623] [<c17c9526>] pcibios_resource_survey+0x23/0x2a [ 7.202184] [<c17cad8a>] pcibios_init+0x23/0x35 [ 7.206789] [<c17ca574>] pci_subsys_init+0x3f/0x44 [ 7.211659] [<c1002088>] do_one_initcall+0x72/0x122 [ 7.216615] [<c17ca535>] ? pci_legacy_init+0x3d/0x3d [ 7.221659] [<c17a27ff>] kernel_init+0xa6/0x118 [ 7.226265] [<c17a2759>] ? start_kernel+0x334/0x334 [ 7.231223] [<c14d7482>] kernel_thread_helper+0x6/0x10 Signed-off-by: Octavian Purdila <octavian.purdila@intel.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* taskstats: check nla_reserve() returnAlan Cox2012-07-301-0/+5
| | | | | | | | | Addresses https://bugzilla.kernel.org/show_bug.cgi?id=44621 Reported-by: <rucsoftsec@gmail.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysctl: suppress kmemleak messagesSteven Rostedt2012-07-301-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | register_sysctl_table() is a strange function, as it makes internal allocations (a header) to register a sysctl_table. This header is a handle to the table that is created, and can be used to unregister the table. But if the table is permanent and never unregistered, the header acts the same as a static variable. Unfortunately, this allocation of memory that is never expected to be freed fools kmemleak in thinking that we have leaked memory. For those sysctl tables that are never unregistered, and have no pointer referencing them, kmemleak will think that these are memory leaks: unreferenced object 0xffff880079fb9d40 (size 192): comm "swapper/0", pid 0, jiffies 4294667316 (age 12614.152s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8146b590>] kmemleak_alloc+0x73/0x98 [<ffffffff8110a935>] kmemleak_alloc_recursive.constprop.42+0x16/0x18 [<ffffffff8110b852>] __kmalloc+0x107/0x153 [<ffffffff8116fa72>] kzalloc.constprop.8+0xe/0x10 [<ffffffff811703c9>] __register_sysctl_paths+0xe1/0x160 [<ffffffff81170463>] register_sysctl_paths+0x1b/0x1d [<ffffffff8117047d>] register_sysctl_table+0x18/0x1a [<ffffffff81afb0a1>] sysctl_init+0x10/0x14 [<ffffffff81b05a6f>] proc_sys_init+0x2f/0x31 [<ffffffff81b0584c>] proc_root_init+0xa5/0xa7 [<ffffffff81ae5b7e>] start_kernel+0x3d0/0x40a [<ffffffff81ae52a7>] x86_64_start_reservations+0xae/0xb2 [<ffffffff81ae53ad>] x86_64_start_kernel+0x102/0x111 [<ffffffffffffffff>] 0xffffffffffffffff The sysctl_base_table used by sysctl itself is one such instance that registers the table to never be unregistered. Use kmemleak_not_leak() to suppress the kmemleak false positive. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdump: append newline to the last lien of vmcoreinfo noteVivek Goyal2012-07-301-1/+1
| | | | | | | | | | | | | | | | The last line of vmcoreinfo note does not end with \n. Parsing all the lines in note becomes easier if all lines end with \n instead of trying to special case the last line. I know at least one tool, vmcore-dmesg in kexec-tools tree which made the assumption that all lines end with \n. I think it is a good idea to fix it. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fork: fix error handling in dup_task()Akinobu Mita2012-07-301-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function dup_task() may fail at the following function calls in the following order. 0) alloc_task_struct_node() 1) alloc_thread_info_node() 2) arch_dup_task_struct() Error by 0) is not a matter, it can just return. But error by 1) requires releasing task_struct allocated by 0) before it returns. Likewise, error by 2) requires releasing task_struct and thread_info allocated by 0) and 1). The existing error handling calls free_task_struct() and free_thread_info() which do not only release task_struct and thread_info, but also call architecture specific arch_release_task_struct() and arch_release_thread_info(). The problem is that task_struct and thread_info are not fully initialized yet at this point, but arch_release_task_struct() and arch_release_thread_info() are called with them. For example, x86 defines its own arch_release_task_struct() that releases a task_xstate. If alloc_thread_info_node() fails in dup_task(), arch_release_task_struct() is called with task_struct which is just allocated and filled with garbage in this error handling. This actually happened with tools/testing/fault-injection/failcmd.sh # env FAILCMD_TYPE=fail_page_alloc \ ./tools/testing/fault-injection/failcmd.sh --times=100 \ --min-order=0 --ignore-gfp-wait=0 \ -- make -C tools/testing/selftests/ run_tests In order to fix this issue, make free_{task_struct,thread_info}() not to call arch_release_{task_struct,thread_info}() and call arch_release_{task_struct,thread_info}() implicitly where needed. Default arch_release_task_struct() and arch_release_thread_info() are defined as empty by default. So this change only affects the architectures which implement their own arch_release_task_struct() or arch_release_thread_info() as listed below. arch_release_task_struct(): x86, sh arch_release_thread_info(): mn10300, tile Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Salman Qazi <sqazi@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* revert "sched: Fix fork() error path to not crash"Andrew Morton2012-07-301-8/+3
| | | | | | | | | | | | To make way for "fork: fix error handling in dup_task()", which fixes the errors more completely. Cc: Salman Qazi <sqazi@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fork: use vma_pages() to simplify the codeHuang Shijie2012-07-301-2/+2
| | | | | | | | | | The current code can be replaced by vma_pages(). So use it to simplify the code. [akpm@linux-foundation.org: initialise `len' at its definition site] Signed-off-by: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmod: avoid deadlock from recursive kmod callTetsuo Handa2012-07-301-2/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The system deadlocks (at least since 2.6.10) when call_usermodehelper(UMH_WAIT_EXEC) request triggers call_usermodehelper(UMH_WAIT_PROC) request. This is because "khelper thread is waiting for the worker thread at wait_for_completion() in do_fork() since the worker thread was created with CLONE_VFORK flag" and "the worker thread cannot call complete() because do_execve() is blocked at UMH_WAIT_PROC request" and "the khelper thread cannot start processing UMH_WAIT_PROC request because the khelper thread is waiting for the worker thread at wait_for_completion() in do_fork()". The easiest example to observe this deadlock is to use a corrupted /sbin/hotplug binary (like shown below). # : > /tmp/dummy # chmod 755 /tmp/dummy # echo /tmp/dummy > /proc/sys/kernel/hotplug # modprobe whatever call_usermodehelper("/tmp/dummy", UMH_WAIT_EXEC) is called from kobject_uevent_env() in lib/kobject_uevent.c upon loading/unloading a module. do_execve("/tmp/dummy") triggers a call to request_module("binfmt-0000") from search_binary_handler() which in turn calls call_usermodehelper(UMH_WAIT_PROC). In order to avoid deadlock, as a for-now and easy-to-backport solution, do not try to call wait_for_completion() in call_usermodehelper_exec() if the worker thread was created by khelper thread with CLONE_VFORK flag. Future and fundamental solution might be replacing singleton khelper thread with some workqueue so that recursive calls up to max_active dependency loop can be handled without deadlock. [akpm@linux-foundation.org: add comment to kmod_thread_locker] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kmod.c: document call_usermodehelper_fns() a bitAndrew Morton2012-07-301-0/+6
| | | | | | | | | | | | | | | This function's interface is, uh, subtle. Attempt to apologise for it. Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Kees Cook <keescook@chromium.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Oleg Nesterov <oleg@redhat.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>
* printk: only look for prefix levels in kernel messagesJoe Perches2012-07-301-15/+17
| | | | | | | | | | vprintk_emit() prefix parsing should only be done for internal kernel messages. This allows existing behavior to be kept in all cases. Signed-off-by: Joe Perches <joe@perches.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* printk: add generic functions to find KERN_<LEVEL> headersJoe Perches2012-07-301-5/+9
| | | | | | | | | | | | | | | | | | The current form of a KERN_<LEVEL> is "<.>". Add printk_get_level and printk_skip_level functions to handle these formats. These functions centralize tests of KERN_<LEVEL> so a future modification can change the KERN_<LEVEL> style and shorten the number of bytes consumed by these headers. [akpm@linux-foundation.org: fix build error and warning] Signed-off-by: Joe Perches <joe@perches.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Wu Fengguang <wfg@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kmsg: /dev/kmsg - properly return possible copy_from_user() failureKay Sievers2012-07-301-1/+3
| | | | | | | Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/sys.c: avoid argv_free(NULL)Andrew Morton2012-07-301-19/+25
| | | | | | | | | | | | | | | | | If argv_split() failed, the code will end up calling argv_free(NULL). Fix it up and clean things up a bit. Addresses Coverity report 703573. Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Kees Cook <keescook@chromium.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NMI watchdog: fix for lockup detector breakage on resumeSameer Nanda2012-07-302-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On the suspend/resume path the boot CPU does not go though an offline->online transition. This breaks the NMI detector post-resume since it depends on PMU state that is lost when the system gets suspended. Fix this by forcing a CPU offline->online transition for the lockup detector on the boot CPU during resume. To provide more context, we enable NMI watchdog on Chrome OS. We have seen several reports of systems freezing up completely which indicated that the NMI watchdog was not firing for some reason. Debugging further, we found a simple way of repro'ing system freezes -- issuing the command 'tasket 1 sh -c "echo nmilockup > /proc/breakme"' after the system has been suspended/resumed one or more times. With this patch in place, the system freeze result in panics, as expected. These panics provide a nice stack trace for us to debug the actual issue causing the freeze. [akpm@linux-foundation.org: fiddle with code comment] [akpm@linux-foundation.org: make lockup_detector_bootcpu_resume() conditional on CONFIG_SUSPEND] [akpm@linux-foundation.org: fix section errors] Signed-off-by: Sameer Nanda <snanda@chromium.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Don Zickus <dzickus@redhat.com> Cc: Mandeep Singh Baines <msb@chromium.org> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* panic: fix a possible deadlock in panic()Vikram Mulukutla2012-07-301-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | panic_lock is meant to ensure that panic processing takes place only on one cpu; if any of the other cpus encounter a panic, they will spin waiting to be shut down. However, this causes a regression in this scenario: 1. Cpu 0 encounters a panic and acquires the panic_lock and proceeds with the panic processing. 2. There is an interrupt on cpu 0 that also encounters an error condition and invokes panic. 3. This second invocation fails to acquire the panic_lock and enters the infinite while loop in panic_smp_self_stop. Thus all panic processing is stopped, and the cpu is stuck for eternity in the while(1) inside panic_smp_self_stop. To address this, disable local interrupts with local_irq_disable before acquiring the panic_lock. This will prevent interrupt handlers from executing during the panic processing, thus avoiding this particular problem. Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* coredump: warn about unsafe suid_dumpable / core_pattern comboKees Cook2012-07-301-2/+35
| | | | | | | | | | | | | | | | When suid_dumpable=2, detect unsafe core_pattern settings and warn when they are seen. Signed-off-by: Kees Cook <keescook@chromium.org> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alan Cox <alan@linux.intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Doug Ledford <dledford@redhat.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: James Morris <james.l.morris@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* prctl: remove redunant assignment of "error" to zeroSasikantha babu2012-07-301-11/+2
| | | | | | | | | | | | | | Just setting the "error" to error number is enough on failure and It doesn't require to set "error" variable to zero in each switch case, since it was already initialized with zero. And also removed return 0 in switch case with break statement Signed-off-by: Sasikantha babu <sasikanth.v19@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Serge E. Hallyn <serge@hallyn.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* posix_types.h: Cleanup stale __NFDBITS and related definitionsJosh Boyer2012-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Recently, glibc made a change to suppress sign-conversion warnings in FD_SET (glibc commit ceb9e56b3d1). This uncovered an issue with the kernel's definition of __NFDBITS if applications #include <linux/types.h> after including <sys/select.h>. A build failure would be seen when passing the -Werror=sign-compare and -D_FORTIFY_SOURCE=2 flags to gcc. It was suggested that the kernel should either match the glibc definition of __NFDBITS or remove that entirely. The current in-kernel uses of __NFDBITS can be replaced with BITS_PER_LONG, and there are no uses of the related __FDELT and __FDMASK defines. Given that, we'll continue the cleanup that was started with commit 8b3d1cda4f5f ("posix_types: Remove fd_set macros") and drop the remaining unused macros. Additionally, linux/time.h has similar macros defined that expand to nothing so we'll remove those at the same time. Reported-by: Jeff Law <law@redhat.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> CC: <stable@vger.kernel.org> Signed-off-by: Josh Boyer <jwboyer@redhat.com> [ .. and fix up whitespace as per akpm ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2012-07-264-86/+272
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "The biggest change is a performance improvement on SMP systems: | 4 socket 40 core + SMT Westmere box, single 30 sec tbench | runs, higher is better: | | clients 1 2 4 8 16 32 64 128 |.......................................................................... | pre 30 41 118 645 3769 6214 12233 14312 | post 299 603 1211 2418 4697 6847 11606 14557 | | A nice increase in performance. which speedup is particularly noticeable on heavily interacting few-tasks workloads, so the changes should help desktop-style Xorg workloads and interactivity as well, on multi-core CPUs. There are also cpuset suspend behavior fixes/restructuring and various smaller tweaks." * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix race in task_group() sched: Improve balance_cpu() to consider other cpus in its group as target of (pinned) task sched: Reset loop counters if all tasks are pinned and we need to redo load balance sched: Reorder 'struct lb_env' members to reduce its size sched: Improve scalability via 'CPU buddies', which withstand random perturbations cpusets: Remove/update outdated comments cpusets, hotplug: Restructure functions that are invoked during hotplug cpusets, hotplug: Implement cpuset tree traversal in a helper function CPU hotplug, cpusets, suspend: Don't modify cpusets during suspend/resume sched/x86: Remove broken power estimation
| * sched: Fix race in task_group()Peter Zijlstra2012-07-242-14/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stefan reported a crash on a kernel before a3e5d1091c1 ("sched: Don't call task_group() too many times in set_task_rq()"), he found the reason to be that the multiple task_group() invocations in set_task_rq() returned different values. Looking at all that I found a lack of serialization and plain wrong comments. The below tries to fix it using an extra pointer which is updated under the appropriate scheduler locks. Its not pretty, but I can't really see another way given how all the cgroup stuff works. Reported-and-tested-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1340364965.18025.71.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched: Improve balance_cpu() to consider other cpus in its group as target ↵Srivatsa Vaddagiri2012-07-241-4/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | of (pinned) task Current load balance scheme requires only one cpu in a sched_group (balance_cpu) to look at other peer sched_groups for imbalance and pull tasks towards itself from a busy cpu. Tasks thus pulled by balance_cpu could later get picked up by cpus that are in the same sched_group as that of balance_cpu. This scheme however fails to pull tasks that are not allowed to run on balance_cpu (but are allowed to run on other cpus in its sched_group). That can affect fairness and in some worst case scenarios cause starvation. Consider a two core (2 threads/core) system running tasks as below: Core0 Core1 / \ / \ C0 C1 C2 C3 | | | | v v v v F0 T1 F1 [idle] T2 F0 = SCHED_FIFO task (pinned to C0) F1 = SCHED_FIFO task (pinned to C2) T1 = SCHED_OTHER task (pinned to C1) T2 = SCHED_OTHER task (pinned to C1 and C2) F1 could become a cpu hog, which will starve T2 unless C1 pulls it. Between C0 and C1 however, C0 is required to look for imbalance between cores, which will fail to pull T2 towards Core0. T2 will starve eternally in this case. The same scenario can arise in presence of non-rt tasks as well (say we replace F1 with high irq load). We tackle this problem by having balance_cpu move pinned tasks to one of its sibling cpus (where they can run). We first check if load balance goal can be met by ignoring pinned tasks, failing which we retry move_tasks() with a new env->dst_cpu. This patch modifies load balance semantics on who can move load towards a given cpu in a given sched_domain. Before this patch, a given_cpu or a ilb_cpu acting on behalf of an idle given_cpu is responsible for moving load to given_cpu. With this patch applied, balance_cpu can in addition decide on moving some load to a given_cpu. There is a remote possibility that excess load could get moved as a result of this (balance_cpu and given_cpu/ilb_cpu deciding *independently* and at *same* time to move some load to a given_cpu). However we should see less of such conflicting decisions in practice and moreover subsequent load balance cycles should correct the excess load moved to given_cpu. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4FE06CDB.2060605@linux.vnet.ibm.com [ minor edits ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched: Reset loop counters if all tasks are pinned and we need to redo load ↵Prashanth Nageshappa2012-07-241-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | balance While load balancing, if all tasks on the source runqueue are pinned, we retry after excluding the corresponding source cpu. However, loop counters env.loop and env.loop_break are not reset before retrying, which can lead to failure in moving the tasks. In this patch we reset env.loop and env.loop_break to their inital values before we retry. Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4FE06EEF.2090709@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched: Reorder 'struct lb_env' members to reduce its sizePrashanth Nageshappa2012-07-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Members of 'struct lb_env' are not in appropriate order to reuse compiler added padding on 64bit architectures. In this patch we reorder those struct members and help reduce the size of the structure from 96 bytes to 80 bytes on 64 bit architectures. Suggested-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4FE06DDE.7000403@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched: Improve scalability via 'CPU buddies', which withstand random ↵Mike Galbraith2012-07-242-22/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | perturbations Traversing an entire package is not only expensive, it also leads to tasks bouncing all over a partially idle and possible quite large package. Fix that up by assigning a 'buddy' CPU to try to motivate. Each buddy may try to motivate that one other CPU, if it's busy, tough, it may then try its SMT sibling, but that's all this optimization is allowed to cost. Sibling cache buddies are cross-wired to prevent bouncing. 4 socket 40 core + SMT Westmere box, single 30 sec tbench runs, higher is better: clients 1 2 4 8 16 32 64 128 .......................................................................... pre 30 41 118 645 3769 6214 12233 14312 post 299 603 1211 2418 4697 6847 11606 14557 A nice increase in performance. Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1339471112.7352.32.camel@marge.simpson.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * cpusets: Remove/update outdated commentsSrivatsa S. Bhat2012-07-241-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cpuset_track_online_cpus() is no longer present. So remove the outdated comment and replace it with reference to cpuset_update_active_cpus() which is its equivalent. Also, we don't lack memory hot-unplug anymore. And David Rientjes pointed out how it is dealt with. So update that comment as well. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120524141700.3692.98192.stgit@srivatsabhat.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * cpusets, hotplug: Restructure functions that are invoked during hotplugSrivatsa S. Bhat2012-07-242-29/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Separate out the cpuset related handling for CPU/Memory online/offline. This also helps us exploit the most obvious and basic level of optimization that any notification mechanism (CPU/Mem online/offline) has to offer us: "We *know* why we have been invoked. So stop pretending that we are lost, and do only the necessary amount of processing!". And while at it, rename scan_for_empty_cpusets() to scan_cpusets_upon_hotplug(), which is more appropriate considering how it is restructured. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120524141650.3692.48637.stgit@srivatsabhat.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * cpusets, hotplug: Implement cpuset tree traversal in a helper functionSrivatsa S. Bhat2012-07-241-9/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At present, the functions that deal with cpusets during CPU/Mem hotplug are quite messy, since a lot of the functionality is mixed up without clear separation. And this takes a toll on optimization as well. For example, the function cpuset_update_active_cpus() is called on both CPU offline and CPU online events; and it invokes scan_for_empty_cpusets(), which makes sense only for CPU offline events. And hence, the current code ends up unnecessarily traversing the cpuset tree during CPU online also. As a first step towards cleaning up those functions, encapsulate the cpuset tree traversal in a helper function, so as to facilitate upcoming changes. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120524141635.3692.893.stgit@srivatsabhat.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * CPU hotplug, cpusets, suspend: Don't modify cpusets during suspend/resumeSrivatsa S. Bhat2012-07-242-4/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the event of CPU hotplug, the kernel modifies the cpusets' cpus_allowed masks as and when necessary to ensure that the tasks belonging to the cpusets have some place (online CPUs) to run on. And regular CPU hotplug is destructive in the sense that the kernel doesn't remember the original cpuset configurations set by the user, across hotplug operations. However, suspend/resume (which uses CPU hotplug) is a special case in which the kernel has the responsibility to restore the system (during resume), to exactly the same state it was in before suspend. In order to achieve that, do the following: 1. Don't modify cpusets during suspend/resume. At all. In particular, don't move the tasks from one cpuset to another, and don't modify any cpuset's cpus_allowed mask. So, simply ignore cpusets during the CPU hotplug operations that are carried out in the suspend/resume path. 2. However, cpusets and sched domains are related. We just want to avoid altering cpusets alone. So, to keep the sched domains updated, build a single sched domain (containing all active cpus) during each of the CPU hotplug operations carried out in s/r path, effectively ignoring the cpusets' cpus_allowed masks. (Since userspace is frozen while doing all this, it will go unnoticed.) 3. During the last CPU online operation during resume, build the sched domains by looking up the (unaltered) cpusets' cpus_allowed masks. That will bring back the system to the same original state as it was in before suspend. Ultimately, this will not only solve the cpuset problem related to suspend resume (ie., restores the cpusets to exactly what it was before suspend, by not touching it at all) but also speeds up suspend/resume because we avoid running cpuset update code for every CPU being offlined/onlined. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20120524141611.3692.20155.stgit@srivatsabhat.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge tag 'driver-core-3.6-rc1' of ↵Linus Torvalds2012-07-261-38/+121
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core changes from Greg Kroah-Hartman: "Here's the big driver core pull request for 3.6-rc1. Unlike 3.5, this kernel should be a lot tamer, with the printk changes now settled down. All we have here is some extcon driver updates, w1 driver updates, a few printk cleanups that weren't needed for 3.5, but are good to have now, and some other minor fixes/changes in the driver core. All of these have been in the linux-next releases for a while now. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'driver-core-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits) printk: Export struct log size and member offsets through vmcoreinfo Drivers: hv: Change the hex constant to a decimal constant driver core: don't trigger uevent after failure extcon: MAX77693: Add extcon-max77693 driver to support Maxim MAX77693 MUIC device sysfs: fail dentry revalidation after namespace change fix sysfs: fail dentry revalidation after namespace change extcon: spelling of detach in function doc extcon: arizona: Stop microphone detection if we give up on it extcon: arizona: Update cable reporting calls and split headset PM / Runtime: Do not increment device usage counts before probing kmsg - do not flush partial lines when the console is busy kmsg - export "continuation record" flag to /dev/kmsg kmsg - avoid warning for CONFIG_PRINTK=n compilations kmsg - properly print over-long continuation lines driver-core: Use kobj_to_dev instead of re-implementing it driver-core: Move kobj_to_dev from genhd.h to device.h driver core: Move deferred devices to the end of dpm_list before probing driver core: move uevent call to driver_register driver core: fix shutdown races with probe/remove(v3) Extcon: Arizona: Add driver for Wolfson Arizona class devices ...
| * | printk: Export struct log size and member offsets through vmcoreinfoVivek Goyal2012-07-191-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are tools like makedumpfile and vmcore-dmesg which can extract kernel log buffer from vmcore. Since we introduced structured logging, that functionality is broken. Now user space tools need to know about "struct log" and offsets of various fields to be able to parse struct log data and extract text message or dictonary. This patch exports some of the fields. Currently I am not exporting log "level" info as that is a bitfield and offsetof() bitfields can't be calculated. But if people start asking for log level info in the output then we probably either need to seprate out "level" or use bit shift operations for flags and level. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | kmsg - do not flush partial lines when the console is busyKay Sievers2012-07-161-25/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fragments of continuation lines are flushed to the console immediately. In case the console is locked, the fragment must be queued up in the cont buffer. If the the console is busy and the continuation line is complete, but no part of it was written to the console up to this point, we can just store the entire line as a regular record and free the buffer earlier. If the console is busy and earlier messages are already queued up, we should not flush the fragments of continuation lines, but store them after the queued up messages, to ensure the proper ordering. This keeps the console output better readable in case printk()s race against each other, or we receive over-long continuation lines we need to flush. Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | kmsg - export "continuation record" flag to /dev/kmsgKay Sievers2012-07-161-2/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases we are forced to store individual records for a continuation line print. Export a flag to allow the external re-construction of the line. The flag allows us to apply a similar logic externally which is used internally when the console, /proc/kmsg or the syslog() output is printed. $ cat /dev/kmsg 4,165,0,-;Free swap = 0kB 4,166,0,-;Total swap = 0kB 6,167,0,c;[ 4,168,0,+;0 4,169,0,+;1 4,170,0,+;2 4,171,0,+;3 4,172,0,+;] 6,173,0,-;[0 1 2 3 ] 6,174,0,-;Console: colour VGA+ 80x25 6,175,0,-;console [tty0] enabled Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | kmsg - avoid warning for CONFIG_PRINTK=n compilationsKay Sievers2012-07-161-2/+9
| | | | | | | | | | | | | | | Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | kmsg - properly print over-long continuation linesKay Sievers2012-07-161-14/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reserve PREFIX_MAX bytes in the LOG_LINE_MAX line when buffering a continuation line, to be able to properly prefix the LOG_LINE_MAX line with the syslog prefix and timestamp when printing it. Reported-By: Dave Jones <davej@redhat.com> Signed-off-by: Kay Sievers <kay@vrfy.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | Merge tag 'staging-3.6-rc1' of ↵Linus Torvalds2012-07-262-12/+31
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging tree patches from Greg Kroah-Hartman: "Here's the big staging tree merge for the 3.6-rc1 merge window. There are some patches in here outside of drivers/staging/, notibly the iio code (which is still stradeling the staging / not staging boundry), the pstore code, and the tracing code. All of these have gotten acks from the various subsystem maintainers to be included in this tree. The pstore and tracing patches are related, and are coming here as they replace one of the android staging drivers. Otherwise, the normal staging mess. Lots of cleanups and a few new drivers (some iio drivers, and the large csr wireless driver abomination.) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fixed up trivial conflicts in drivers/staging/comedi/drivers/s626.h and drivers/staging/gdm72xx/netlink_k.c * tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1108 commits) staging: csr: delete a bunch of unused library functions staging: csr: remove csr_utf16.c staging: csr: remove csr_pmem.h staging: csr: remove CsrPmemAlloc staging: csr: remove CsrPmemFree() staging: csr: remove CsrMemAllocDma() staging: csr: remove CsrMemCalloc() staging: csr: remove CsrMemAlloc() staging: csr: remove CsrMemFree() and CsrMemFreeDma() staging: csr: remove csr_util.h staging: csr: remove CsrOffSetOf() stating: csr: remove unneeded #includes in csr_util.c staging: csr: make CsrUInt16ToHex static staging: csr: remove CsrMemCpy() staging: csr: remove CsrStrLen() staging: csr: remove CsrVsnprintf() staging: csr: remove CsrStrDup staging: csr: remove CsrStrChr() staging: csr: remove CsrStrNCmp staging: csr: remove CsrStrCmp ...
| * | | tracing/function: Convert func_set_flag() to a switch statementAnton Vorontsov2012-07-171-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the function accepts just one bit, we can use the switch construction instead of if/else if/... Just a cosmetic change, there should be no functional changes. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | tracing/function: Introduce persistent trace optionAnton Vorontsov2012-07-171-5/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces 'func_ptrace' option, now available in /sys/kernel/debug/tracing/options when function tracer is selected. The patch also adds some tiny code that calls back to pstore to record the trace. The callback is no-op when PSTORE=n. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | tracing: Fix initialization failure path in tracing_set_tracer()Anton Vorontsov2012-07-171-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If tracer->init() fails, current code will leave current_tracer pointing to an unusable tracer, which at best makes 'current_tracer' report inaccurate value. Fix the issue by pointing current_tracer to nop tracer, and only update current_tracer with the new one after all the initialization succeeds. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | | Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2012-07-241-19/+57
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull first round of SCSI updates from James Bottomley: "The most important feature of this patch set is the new async infrastructure that makes sure async_synchronize_full() synchronizes all domains and allows us to remove all the hacks (like having scsi_complete_async_scans() in the device base code) and means that the async infrastructure will "just work" in future. The rest is assorted driver updates (aacraid, bnx2fc, virto-scsi, megaraid, bfa, lpfc, qla2xxx, qla4xxx) plus a lot of infrastructure work in sas and FC. Signed-off-by: James Bottomley <JBottomley@Parallels.com>" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (97 commits) [SCSI] Revert "[SCSI] fix async probe regression" [SCSI] cleanup usages of scsi_complete_async_scans [SCSI] queue async scan work to an async_schedule domain [SCSI] async: make async_synchronize_full() flush all work regardless of domain [SCSI] async: introduce 'async_domain' type [SCSI] bfa: Fix to set correct return error codes and misc cleanup. [SCSI] aacraid: Series 7 Async. (performance) mode support [SCSI] aha152x: Allow use on 64bit systems [SCSI] virtio-scsi: Add vdrv->scan for post VIRTIO_CONFIG_S_DRIVER_OK LUN scanning [SCSI] bfa: squelch lockdep complaint with a spin_lock_init [SCSI] qla2xxx: remove unnecessary reads of PCI_CAP_ID_EXP [SCSI] qla4xxx: remove unnecessary read of PCI_CAP_ID_EXP [SCSI] ufs: fix incorrect return value about SUCCESS and FAILED [SCSI] ufs: reverse the ufshcd_is_device_present logic [SCSI] ufs: use module_pci_driver [SCSI] usb-storage: update usb devices for write cache quirk in quirk list. [SCSI] usb-storage: add support for write cache quirk [SCSI] set to WCE if usb cache quirk is present. [SCSI] virtio-scsi: hotplug support for virtio-scsi [SCSI] virtio-scsi: split scatterlist per target ...
| * | | | [SCSI] async: make async_synchronize_full() flush all work regardless of domainDan Williams2012-07-201-2/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In response to an async related regression James noted: "My theory is that this is an init problem: The assumption in a lot of our code is that async_synchronize_full() waits for everything ... even the domain specific async schedules, which isn't true." ...so make this assumption true. Each domain, including the default one, registers itself on a global domain list when work is scheduled. Once all entries complete it exits that list. Waiting for the list to be empty syncs all in-flight work across all domains. Domains can opt-out of global syncing if they are declared as exclusive ASYNC_DOMAIN_EXCLUSIVE(). All stack-based domains have been declared exclusive since the domain may go out of scope as soon as the last work item completes. Statically declared domains are mostly ok, but async_unregister_domain() is there to close any theoretical races with pending async_synchronize_full waiters at module removal time. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Reported-by: Meelis Roos <mroos@linux.ee> Reported-by: Eldad Zack <eldadzack@gmail.com> Tested-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
| * | | | [SCSI] async: introduce 'async_domain' typeDan Williams2012-07-201-18/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is in preparation for teaching async_synchronize_full() to sync all pending async work, and not just on the async_running domain. This conversion is functionally equivalent, just embedding the existing list in a new async_domain type. The .registered attribute is used in a later patch to distinguish between domains that want to be flushed by async_synchronize_full() versus those that only expect async_synchronize_{full|cookie}_domain to be used for flushing. [jejb: add async.h to scsi_priv.h for struct async_domain] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Tested-by: Eldad Zack <eldad@fogrefinery.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
* | | | | Merge branch 'for-3.6' of ↵Linus Torvalds2012-07-241-46/+1
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup changes from Tejun Heo: "Nothing too interesting. A minor bug fix and some cleanups." * 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Update remount documentation cgroup: cgroup_rm_files() was calling simple_unlink() with the wrong inode cgroup: Remove populate() documentation cgroup: remove hierarchy_mutex
| * | | | | cgroup: cgroup_rm_files() was calling simple_unlink() with the wrong inodeTejun Heo2012-07-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While refactoring cgroup file removal path, 05ef1d7c4a "cgroup: introduce struct cfent" incorrectly changed the @dir argument of simple_unlink() to the inode of the file being deleted instead of that of the containing directory. The effect of this bug is minor - ctime and mtime of the parent weren't properly updated on file deletion. Fix it by using @cgrp->dentry->d_inode instead. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Li Zefan <lizefan@huawei.com> Cc: stable@vger.kernel.org
| * | | | | cgroup: remove hierarchy_mutexLi Zefan2012-06-061-45/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was introduced for memcg to iterate cgroup hierarchy without holding cgroup_mutex, but soon after that it was replaced with a lockless way in memcg. No one used hierarchy_mutex since that, so remove it. Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | | | | | Merge branch 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds2012-07-242-648/+584
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull workqueue changes from Tejun Heo: "There are three major changes. - WQ_HIGHPRI has been reimplemented so that high priority work items are served by worker threads with -20 nice value from dedicated highpri worker pools. - CPU hotplug support has been reimplemented such that idle workers are kept across CPU hotplug events. This makes CPU hotplug cheaper (for PM) and makes the code simpler. - flush_kthread_work() has been reimplemented so that a work item can be freed while executing. This removes an annoying behavior difference between kthread_worker and workqueue." * 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: fix spurious CPU locality WARN from process_one_work() kthread_worker: reimplement flush_kthread_work() to allow freeing the work item being executed kthread_worker: reorganize to prepare for flush_kthread_work() reimplementation workqueue: simplify CPU hotplug code workqueue: remove CPU offline trustee workqueue: don't butcher idle workers on an offline CPU workqueue: reimplement CPU online rebinding to handle idle workers workqueue: drop @bind from create_worker() workqueue: use mutex for global_cwq manager exclusion workqueue: ROGUE workers are UNBOUND workers workqueue: drop CPU_DYING notifier operation workqueue: perform cpu down operations from low priority cpu_notifier() workqueue: reimplement WQ_HIGHPRI using a separate worker_pool workqueue: introduce NR_WORKER_POOLS and for_each_worker_pool() workqueue: separate out worker_pool flags workqueue: use @pool instead of @gcwq or @cpu where applicable workqueue: factor out worker_pool from global_cwq workqueue: don't use WQ_HIGHPRI for unbound workqueues
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