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2006-11-22Don't call "note_interrupt()" with irq descriptor lock heldLinus Torvalds
This reverts commit f72fa707604c015a6625e80f269506032d5430dc, and solves the problem that it tried to fix by simply making "__do_IRQ()" call the note_interrupt() function without the lock held, the way everybody else does. It should be noted that all interrupt handling code must never allow the descriptor actors to be entered "recursively" (that's why we do all the magic IRQ_PENDING stuff in the first place), so there actually is exclusion at that much higher level, even in the absense of locking. Acked-by: Vivek Goyal <vgoyal@in.ibm.com> Acked-by:Pavel Emelianov <xemul@openvz.org> Cc: Andrew Morton <akpm@osdl.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-17[PATCH] lockdep: fix static keys in module-allocated percpu areasIngo Molnar
lockdep got confused by certain locks in modules: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. Call Trace: [<ffffffff8026f40d>] dump_trace+0xaa/0x3f2 [<ffffffff8026f78f>] show_trace+0x3a/0x60 [<ffffffff8026f9d1>] dump_stack+0x15/0x17 [<ffffffff802abfe8>] __lock_acquire+0x724/0x9bb [<ffffffff802ac52b>] lock_acquire+0x4d/0x67 [<ffffffff80267139>] rt_spin_lock+0x3d/0x41 [<ffffffff8839ed3f>] :ip_conntrack:__ip_ct_refresh_acct+0x131/0x174 [<ffffffff883a1334>] :ip_conntrack:udp_packet+0xbf/0xcf [<ffffffff8839f9af>] :ip_conntrack:ip_conntrack_in+0x394/0x4a7 [<ffffffff8023551f>] nf_iterate+0x41/0x7f [<ffffffff8025946a>] nf_hook_slow+0x64/0xd5 [<ffffffff802369a2>] ip_rcv+0x24e/0x506 [...] Steven Rostedt found the bug: static_obj() check did not take PERCPU_ENOUGH_ROOM into account, so in-module DEFINE_PER_CPU-area locks were triggering this message. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-16[PATCH] some irq_chip variables point to NULLZhang, Yanmin
I got an oops when booting 2.6.19-rc5-mm1 on my ia64 machine. Below is the log. Oops 11012296146944 [1] Modules linked in: binfmt_misc dm_mirror dm_multipath dm_mod thermal processor f an container button sg eepro100 e100 mii Pid: 0, CPU 0, comm: swapper psr : 0000121008022038 ifs : 800000000000040b ip : [<a0000001000e1411>] Not tainted ip is at __do_IRQ+0x371/0x3e0 unat: 0000000000000000 pfs : 000000000000040b rsc : 0000000000000003 rnat: 656960155aa56aa5 bsps: a00000010058b890 pr : 656960155aa55a65 ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c0270033f csd : 0000000000000000 ssd : 0000000000000000 b0 : a0000001000e1390 b6 : a0000001005beac0 b7 : e00000007f01aa00 f6 : 000000000000000000000 f7 : 0ffe69090000000000000 f8 : 1000a9090000000000000 f9 : 0ffff8000000000000000 f10 : 1000a908ffffff6f70000 f11 : 1003e0000000000000909 r1 : a000000100fbbff0 r2 : 0000000000010002 r3 : 0000000000010001 r8 : fffffffffffbffff r9 : a000000100bd8060 r10 : a000000100dd83b8 r11 : fffffffffffeffff r12 : a000000100bcbbb0 r13 : a000000100bc4000 r14 : 0000000000010000 r15 : 0000000000010000 r16 : a000000100c01aa8 r17 : a000000100d2c350 r18 : 0000000000000000 r19 : a000000100d2c300 r20 : a000000100c01a88 r21 : 0000000080010100 r22 : a000000100c01ac0 r23 : a0000001000108e0 r24 : e000000477980004 r25 : 0000000000000000 r26 : 0000000000000000 r27 : e00000000913400c r28 : e0000004799ee51c r29 : e0000004778b87f0 r30 : a000000100d2c300 r31 : a00000010005c7e0 Call Trace: [<a000000100014600>] show_stack+0x40/0xa0 sp=a000000100bcb760 bsp=a000000100bc4f40 [<a000000100014f00>] show_regs+0x840/0x880 sp=a000000100bcb930 bsp=a000000100bc4ee8 [<a000000100037fb0>] die+0x250/0x320 sp=a000000100bcb930 bsp=a000000100bc4ea0 [<a00000010005e5f0>] ia64_do_page_fault+0x8d0/0xa20 sp=a000000100bcb950 bsp=a000000100bc4e50 [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290 sp=a000000100bcb9e0 bsp=a000000100bc4e50 [<a0000001000e1410>] __do_IRQ+0x370/0x3e0 sp=a000000100bcbbb0 bsp=a000000100bc4df0 [<a000000100011f50>] ia64_handle_irq+0x170/0x220 sp=a000000100bcbbb0 bsp=a000000100bc4dc0 [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290 sp=a000000100bcbbb0 bsp=a000000100bc4dc0 [<a000000100012390>] ia64_pal_call_static+0x90/0xc0 sp=a000000100bcbd80 bsp=a000000100bc4d78 [<a000000100015630>] default_idle+0x90/0x160 sp=a000000100bcbd80 bsp=a000000100bc4d58 [<a000000100014290>] cpu_idle+0x1f0/0x440 sp=a000000100bcbe20 bsp=a000000100bc4d18 [<a000000100009980>] rest_init+0xc0/0xe0 sp=a000000100bcbe20 bsp=a000000100bc4d00 [<a0000001009f8ea0>] start_kernel+0x6a0/0x6c0 sp=a000000100bcbe20 bsp=a000000100bc4ca0 [<a0000001000089f0>] __end_ivt_text+0x6d0/0x6f0 sp=a000000100bcbe30 bsp=a000000100bc4c00 <0>Kernel panic - not syncing: Aiee, killing interrupt handler! The root cause is that some irq_chip variables, especially ia64_msi_chip, initiate their memeber end to point to NULL. __do_IRQ doesn't check if irq_chip->end is null and just calls it after processing the interrupt. As irq_chip->end is called at many places, so I fix it by reinitiating irq_chip->end to dummy_irq_chip.end, e.g., a noop function. Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-14Revert "[PATCH] fix Data Acess error in dup_fd"Linus Torvalds
This reverts commit 0130b0b32ee53dc7add773fcea984f6a26ef1da3. Sergey Vlasov points out (and Vadim Lobanov concurs) that the bug it was supposed to fix must be some unrelated memory corruption, and the "fix" actually causes more problems: "However, the new code does not look safe in all cases. If some other task has opened more files while dup_fd() released oldf->file_lock, the new code will update open_files to the new larger value. But newf was allocated with the old smaller value of open_files, therefore subsequent accesses to newf may try to write into unallocated memory." so revert it. Cc: Sharyathi Nagesh <sharyath@in.ibm.com> Cc: Sergey Vlasov <vsu@altlinux.ru> Cc: Vadim Lobanov <vlobanov@speakeasy.net> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-14[PATCH] setup_irq(): better mismatch debuggingAndrew Morton
When we get a mismatch between handlers on the same IRQ, all we get is "IRQ handler type mismatch for IRQ n". Let's print the name of the presently-registered handler with which we got the mismatch. Cc: 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>
2006-11-13[PATCH] Fix misrouted interrupts deadlocksPavel Emelianov
While testing kernel on machine with "irqpoll" option I've caught such a lockup: __do_IRQ() spin_lock(&desc->lock); desc->chip->ack(); /* IRQ is ACKed */ note_interrupt() misrouted_irq() handle_IRQ_event() if (...) local_irq_enable_in_hardirq(); /* interrupts are enabled from now */ ... __do_IRQ() /* same IRQ we've started from */ spin_lock(&desc->lock); /* LOCKUP */ Looking at misrouted_irq() code I've found that a potential deadlock like this can also take place: 1CPU: __do_IRQ() spin_lock(&desc->lock); /* irq = A */ misrouted_irq() for (i = 1; i < NR_IRQS; i++) { spin_lock(&desc->lock); /* irq = B */ if (desc->status & IRQ_INPROGRESS) { 2CPU: __do_IRQ() spin_lock(&desc->lock); /* irq = B */ misrouted_irq() for (i = 1; i < NR_IRQS; i++) { spin_lock(&desc->lock); /* irq = A */ if (desc->status & IRQ_INPROGRESS) { As the second lock on both CPUs is taken before checking that this irq is being handled in another processor this may cause a deadlock. This issue is only theoretical. I propose the attached patch to fix booth problems: when trying to handle misrouted IRQ active desc->lock may be unlocked. Acked-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-13[PATCH] fix Data Acess error in dup_fdSharyathi Nagesh
On running the Stress Test on machine for more than 72 hours following error message was observed. 0:mon> e cpu 0x0: Vector: 300 (Data Access) at [c00000007ce2f7f0] pc: c000000000060d90: .dup_fd+0x240/0x39c lr: c000000000060d6c: .dup_fd+0x21c/0x39c sp: c00000007ce2fa70 msr: 800000000000b032 dar: ffffffff00000028 dsisr: 40000000 current = 0xc000000074950980 paca = 0xc000000000454500 pid = 27330, comm = bash 0:mon> t [c00000007ce2fa70] c000000000060d28 .dup_fd+0x1d8/0x39c (unreliable) [c00000007ce2fb30] c000000000060f48 .copy_files+0x5c/0x88 [c00000007ce2fbd0] c000000000061f5c .copy_process+0x574/0x1520 [c00000007ce2fcd0] c000000000062f88 .do_fork+0x80/0x1c4 [c00000007ce2fdc0] c000000000011790 .sys_clone+0x5c/0x74 [c00000007ce2fe30] c000000000008950 .ppc_clone+0x8/0xc The problem is because of race window. When if(expand) block is executed in dup_fd unlocking of oldf->file_lock give a window for fdtable in oldf to be modified. So actual open_files in oldf may not match with open_files variable. Cc: Vadim Lobanov <vlobanov@speakeasy.net> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-06[PATCH] sysctl: allow a zero ctl_name in the middle of a sysctl tableEric W. Biederman
Since it is becoming clear that there are just enough users of the binary sysctl interface that completely removing the binary interface from the kernel will not be an option for foreseeable future, we need to find a way to address the sysctl maintenance issues. The basic problem is that sysctl requires one central authority to allocate sysctl numbers, or else conflicts and ABI breakage occur. The proc interface to sysctl does not have that problem, as names are not densely allocated. By not terminating a sysctl table until I have neither a ctl_name nor a procname, it becomes simple to add sysctl entries that don't show up in the binary sysctl interface. Which allows people to avoid allocating a binary sysctl value when not needed. I have audited the kernel code and in my reading I have not found a single sysctl table that wasn't terminated by a completely zero filled entry. So this change in behavior should not affect anything. I think this mechanism eases the pain enough that combined with a little disciple we can solve the reoccurring sysctl ABI breakage. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-06[PATCH] Improve the removed sysctl warningsEric W. Biederman
Don't warn about libpthread's access to kernel.version. When it receives -ENOSYS it will read /proc/sys/kernel/version. If anything else shows up print the sysctl number string. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Cal Peake <cp@absolutedigital.net> Cc: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-06[PATCH] lockdep: fix delayacct locking bugPeter Zijlstra
Make the delayacct lock irqsave; this avoids the possible deadlock where an interrupt is taken while holding the delayacct lock which needs to take the delayacct lock. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-06[PATCH] Fix the spurious unlock_cpu_hotplug false warningsGautham R Shenoy
Cpu-hotplug locking has a minor race case caused because of setting the variable "recursive" to NULL *after* releasing the cpu_bitmask_lock in the function unlock_cpu_hotplug,instead of doing so before releasing the cpu_bitmask_lock. This was the cause of most of the recent false spurious lock_cpu_unlock warnings. This should fix the problem reported by Martin Lorenz reported in http://lkml.org/lkml/2006/10/29/127. Thanks to Srinivasa DS for pointing it out. Signed-off-by: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-04Make sure "user->sigpending" count is in syncLinus Torvalds
The previous commit (45c18b0bb579b5c1b89f8c99f1b6ffa4c586ba08, aka "Fix unlikely (but possible) race condition on task->user access") fixed a potential oops due to __sigqueue_alloc() getting its "user" pointer out of sync with switch_user(), and accessing a user pointer that had been de-allocated on another CPU. It still left another (much less serious) problem, where a concurrent __sigqueue_alloc and swich_user could cause sigqueue_alloc to do signal pending reference counting for a _different_ user than the one it then actually ended up using. No oops, but we'd end up with the wrong signal accounting. Another case of Oleg's eagle-eyes picking up the problem. This is trivially fixed by just making sure we load whichever "user" structure we decide to use (it doesn't matter _which_ one we pick, we just need to pick one) just once. Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Andrew Morton <akpm@osdl.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-04Fix unlikely (but possible) race condition on task->user accessLinus Torvalds
There's a possible race condition when doing a "switch_uid()" from one user to another, which could race with another thread doing a signal allocation and looking at the old thread ->user pointer as it is freed. This explains an oops reported by Lukasz Trabinski: http://permalink.gmane.org/gmane.linux.kernel/462241 We fix this by delaying the (reference-counted) freeing of the user structure until the thread signal handler lock has been released, so that we know that the signal allocation has either seen the new value or has properly incremented the reference count of the old one. Race identified by Oleg Nesterov. Cc: Lukasz Trabinski <lukasz@wsisiz.edu.pl> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Andrew Morton <akpm@osdl.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] Create compat_sys_migrate_pagesStephen Rothwell
This is needed on bigendian 64bit architectures. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] swsusp: debuggingRafael J. Wysocki
Add a swsusp debugging mode. This does everything that's needed for a suspend except for actually suspending. So we can look in the log messages and work out a) what code is being slow and b) which drivers are misbehaving. (1) # echo testproc > /sys/power/disk # echo disk > /sys/power/state This should turn off the non-boot CPU, freeze all processes, wait for 5 seconds and then thaw the processes and the CPU. (2) # echo test > /sys/power/disk # echo disk > /sys/power/state This should turn off the non-boot CPU, freeze all processes, shrink memory, suspend all devices, wait for 5 seconds, resume the devices etc. Cc: 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>
2006-11-03[PATCH] schedule removal of FUTEX_FDAndrew Morton
Apparently FUTEX_FD is unfixably racy and nothing uses it (or if it does, it shouldn't). Add a warning printk, give any remaining users six months to migrate off it. Cc: Ulrich Drepper <drepper@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] Add printk_timed_ratelimit()Andrew Morton
printk_ratelimit() has global state which makes it not useful for callers which wish to perform ratelimiting at a particular frequency. Add a printk_timed_ratelimit() which utilises caller-provided state storage to permit more flexibility. This function can in fact be used for things other than printk ratelimiting and is perhaps poorly named. Cc: Ulrich Drepper <drepper@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31[PATCH] taskstats: fix sub-threads accountingOleg Nesterov
If there are no listeners, taskstats_exit_send() just returns because taskstats_exit_alloc() didn't allocate *tidstats. This is wrong, each sub-thread should do fill_tgid_exit() on exit, otherwise its ->delays is not recorded in ->signal->stats and lost. Q: We don't send TASKSTATS_TYPE_AGGR_TGID when single-threaded process exits. Is it good? How can the listener figure out that it was actually a process exit, not sub-thread? Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Balbir Singh <balbir@in.ibm.com> Acked-by: Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-30[PATCH] xacct_add_tsk: fix pure theoretical ->mm use-after-freeOleg Nesterov
Paranoid fix. The task can free its ->mm after the 'if (p->mm)' check. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-30[PATCH] ndiswrapper: don't set the module->taints flagsRandy Dunlap
For ndiswrapper, don't set the module->taints flags, just set the kernel global tainted flag. This should allow ndiswrapper to continue to use GPL symbols. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Florin Malita <fmalita@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-29[PATCH] taskstats: fix sk_buff size calculationOleg Nesterov
prepare_reply() adds GENL_HDRLEN to the payload (genlmsg_total_size()), but then it does genlmsg_put()->nlmsg_put(). This means we forget to reserve a room for 'struct nlmsghdr'. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Thomas Graf <tgraf@suug.ch> Cc: Andrew Morton <akpm@osdl.org> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-29[PATCH] taskstats: fix sk_buff leakOleg Nesterov
'return genlmsg_cancel()' in taskstats_user_cmd/taskstats_exit_send potentially leaks a skb. Unless we pass 'rep_skb' to the netlink layer we own sk_buff. This means we should always do kfree_skb() on failure. [ Thomas acked and pointed out missing return value in original version ] Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Thomas Graf <tgraf@suug.ch> Cc: Andrew Morton <akpm@osdl.org> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] workqueue: update kerneldocAlan Stern
This patch (as812) changes the kerneldoc comments explaining the return values from queue_work(), queue_delayed_work(), and queue_delayed_work_on(). The updated comments explain more accurately the meaning of the return code and avoid suggesting that a 0 value means the routine was unsuccessful. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] cpu-hotplug: release `workqueue_mutex' properly on CPU hot-removeSatoru Takeuchi
_cpu_down() acquires `workqueue_mutex' on its process, but doen't release it if __cpu_disable() fails. Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] time_adjust cleared before useJim Houston
I notice that the code which implements adjtime clears the time_adjust value before using it. The attached patch makes the obvious fix. Acked-by: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Jim Houston <jim.houston@ccur.com> Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] fill_tgid: cleanup delays accountingOleg Nesterov
fill_tgid() should skip not only an already exited group leader. If the task has ->exit_state != 0 it already did exit_notify(), so it also did fill_tgid_exit()->delayacct_add_tsk(->signal->stats) and we should skip it to avoid a double accounting. This patch doesn't close the race completely, but it cleanups the code. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] taskstats: don't use tasklist_lockOleg Nesterov
Remove tasklist_lock from taskstats.c. find_task_by_pid() is rcu-safe. ->siglock allows us to traverse subthread without tasklist. Q: delay accounting looks wrong to me. If sub-thread has already called taskstats_exit_send() but didn't call release_task(self) yet it will be accounted twice. The window is big. No? Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] taskstats: kill ->taskstats_lock in favor of ->siglockOleg Nesterov
signal_struct is (mostly) protected by ->sighand->siglock, I think we don't need ->taskstats_lock to protect ->stats. This also allows us to simplify the locking in fill_tgid(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] taskstats_tgid_free: fix usageOleg Nesterov
taskstats_tgid_free() is called on copy_process's error path. This is wrong. IF (clone_flags & CLONE_THREAD) We should not clear ->signal->taskstats, current uses it, it probably has a valid accumulated info. ELSE taskstats_tgid_init() set ->signal->taskstats = NULL, there is nothing to free. Move the callsite to __exit_signal(). We don't need any locking, entire thread group is exiting, nobody should have a reference to soon to be released ->signal. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] bacct_add_tsk: fix unsafe and wrong parent/group_leader dereferenceOleg Nesterov
1. ts = timespec_sub(uptime, current->group_leader->start_time); It is possible that current != tsk. Probably it was supposed to be 'tsk->group_leader->start_time. But why we are reading group_leader's start_time ? This accounting is per thread, not per procees, I changed this to 'tsk->start_time. Please corect me. 2. stats->ac_ppid = (tsk->parent) ? tsk->parent->pid : 0; tsk->parent never == NULL, and it is unsafe to dereference it. Both the task and it's parent may exit after the caller unlocks tasklist_lock, the memory could be unmapped (DEBUG_SLAB). (And we should use ->real_parent->tgid in fact). Q: I don't understand the 'if (thread_group_leader(tsk))' check. Why it is needed ? Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Acked-by: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] fill_tgid: fix task_struct leak and possible oopsOleg Nesterov
1. fill_tgid() forgets to do put_task_struct(first). 2. release_task(first) can happen after fill_tgid() drops tasklist_lock, it is unsafe to dereference first->signal. This is a temporary fix, imho the locking should be reworked. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] Constify compat_get_bitmap argumentStephen Rothwell
This means we can call it when the bitmap we want to fetch is declared const. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] Add missing space in module.c for taintskernelJan Dittmer
Obvious fix. Signed-off-by: Jan Dittmer <jdi@l4x.org> Acked-by: Florin Malita <fmalita@gmail.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-21[PATCH] x86-64: Speed up dwarf2 unwinderJan Beulich
This changes the dwarf2 unwinder to do a binary search for CIEs instead of a linear work. The linker is unfortunately not able to build a proper lookup table at link time, instead it creates one at runtime as soon as the bootmem allocator is usable (so you'll continue using the linear lookup for the first [hopefully] few calls). The code should be ready to utilize a build-time created table once a fixed linker becomes available. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-10-20[PATCH] kernel/nsproxy.c: use kmemdup()Alexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20[PATCH] cad_pid sysctl with PROC_FS=nRandy Dunlap
If CONFIG_PROC_FS=n: kernel/sysctl.c:148: warning: 'proc_do_cad_pid' used but never defined kernel/built-in.o:(.data+0x1228): undefined reference to `proc_do_cad_pid' make: *** [.tmp_vmlinux1] Error 1 Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20[PATCH] readjust comments of task_timeslice for kernel docBorislav Petkov
Signed-off-by: Borislav Petkov <petkov@math.uni-muenster.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: fm801-gp - handle errors from pci_enable_device() Input: gameport core - handle errors returned by device_bind_driver() Input: serio core - handle errors returned by device_bind_driver() Lockdep: fix compile error in drivers/input/serio/serio.c Input: serio - add lockdep annotations Lockdep: add lockdep_set_class_and_subclass() and lockdep_set_subclass() Input: atkbd - supress "too many keys" error message Input: i8042 - supress ACK/NAKs when blinking during panic Input: add missing exports to fix modular build
2006-10-17[PATCH] Convert cpu hotplug notifiers to use raw_notifier instead of ↵Neil Brown
blocking_notifier The use of blocking notifier by _cpu_up and _cpu_down in cpu.c has two problem. 1/ An interaction with the workqueue notifier causes lockdep to spit a warning. 2/ A notifier could conceivable be added or removed while _cpu_up or _cpu_down are in process. As each notifier is called twice (prepare then commit/abort) this could be unhealthy. To fix to we simply take cpu_add_remove_lock while adding or removing notifiers to/from the list. This makes the 'blocking' usage unnecessary as all accesses to cpu_chain are now protected by cpu_add_remove_lock. So change "blocking" to "raw" in all relevant places. This fixes 1. Credit: Andrew Morton Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> (reporter) Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17[PATCH] rt-mutex: fixup rt-mutex debug codePeter Zijlstra
BUG: warning at kernel/rtmutex-debug.c:125/rt_mutex_debug_task_free() (Not tainted) [<c04051e3>] show_trace_log_lvl+0x58/0x16a [<c04057f0>] show_trace+0xd/0x10 [<c0405900>] dump_stack+0x19/0x1b [<c043f03d>] rt_mutex_debug_task_free+0x35/0x6a [<c04224c0>] free_task+0x15/0x24 [<c042378c>] copy_process+0x12bd/0x1324 [<c0423835>] do_fork+0x42/0x113 [<c04021dd>] sys_fork+0x19/0x1b [<c0403fb7>] syscall_call+0x7/0xb In copy_process(), dup_task_struct() also duplicates the ->pi_lock, ->pi_waiters and ->pi_blocked_on members. rt_mutex_debug_task_free() called from free_task() validates these members. However free_task() can be invoked before these members are reset for the new task. Move the initialization code before the first bail that can hit free_task(). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17[PATCH] genirq: clean up irq-flow-type namingIngo Molnar
Introduce desc->name and eliminate the handle_irq_name() hack. Add set_irq_chip_and_handler_name() to set the flow type and name at once. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Matthew Wilcox <willy@debian.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17[PATCH] swsusp: fix memory leaksAndrew Morton
My fancy new swsusp IO code had a big memory leak. It's somewhat invisible because the whole mem_map[] gets overwritten after resume, but it can cause us to get low on memory during the actual suspend process. Cc: "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>
2006-10-17[PATCH] posix-cpu-timers: prevent signal delivery starvationThomas Gleixner
The integer divisions in the timer accounting code can round the result down to 0. Adding 0 is without effect and the signal delivery stops. Clamp the division result to minimum 1 to avoid this. Problem was reported by Seongbae Park <spark@google.com>, who provided also an inital patch. Roland sayeth: I have had some more time to think about the problem, and to reproduce it using Toyo's test case. For the record, if my understanding of the problem is correct, this happens only in one very particular case. First, the expiry time has to be so soon that in cputime_t units (usually 1s/HZ ticks) it's < nthreads so the division yields zero. Second, it only affects each thread that is so new that its CPU time accumulation is zero so now+0 is still zero and ->it_*_expires winds up staying zero. For the VIRT and PROF clocks when cputime_t is tick granularity (or the SCHED clock on configurations where sched_clock's value only advances on clock ticks), this is not hard to arrange with new threads starting up and blocking before they accumulate a whole tick of CPU time. That's what happens in Toyo's test case. Note that in general it is fine for that division to round down to zero, and set each thread's expiry time to its "now" time. The problem only arises with thread's whose "now" value is still zero, so that now+0 winds up 0 and is interpreted as "not set" instead of ">= now". So it would be a sufficient and more precise fix to just use max(ticks, 1) inside the loop when setting each it_*_expires value. But, it does no harm to round the division up to one and always advance every thread's expiry time. If the thread didn't already fire timers for the expiry time of "now", there is no expectation that it will do so before the next tick anyway. So I followed Thomas's patch in lifting the max out of the loops. This patch also covers the reload cases, which are harder to write a test for (and I didn't try). I've tested it with Toyo's case and it fixes that. [toyoa@mvista.com: fix: min_t -> max_t] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Daniel Walker <dwalker@mvista.com> Cc: Toyo Abe <toyoa@mvista.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Seongbae Park <spark@google.com> Cc: Peter Mattis <pmattis@google.com> Cc: Rohit Seth <rohitseth@google.com> Cc: Martin Bligh <mbligh@google.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17[PATCH] i386 Time: Avoid PIT SMP lockupsjohn stultz
Avoid possible PIT livelock issues seen on SMP systems (and reported by Andi), by not allowing it as a clocksource on SMP boxes. However, since the PIT may no longer be present, we have to properly handle the cases where SMP systems have TSC skew and fall back from the TSC. Since the PIT isn't there, it would "fall back" to the TSC again. So this changes the jiffies rating to 1, and the TSC-bad rating value to 0. Thus you will get the following behavior priority on i386 systems: tsc [if present & stable] hpet [if present] cyclone [if present] acpi_pm [if present] pit [if UP] jiffies Rather then the current more complicated: tsc [if present & stable] hpet [if present] cyclone [if present] acpi_pm [if present] pit [if cpus < 4] tsc [if present & unstable] jiffies Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@suse.de> Cc: 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>
2006-10-17[PATCH] lockdep: increase max allowed recursion depthIngo Molnar
In general, lockdep warnings are intended to be non-fatal, so I have put in various practical limits on internal data structure failure modes. We haven't had a /single/ lockdep-internal crash ever since lockdep went upstream [the unwinder crashes are outside of lockdep], and that's largely due to the good internal checks it does. Recursion within the dependency graph is currently limited to 20, that's probably not enough on some many-CPU boxes - this patch doubles it to 40. I have written the lockdep functions to have as small stackframes as possible, so 40 should be OK too. (The practical recursion limit should be somewhere between 100 and 200 entries. If we hit that then I'll change the algorithm to be iteration-based. Graph walking logic is so easy to program via recursion, so i'd like to keep recursion as long as possible.) Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-16[PATCH] fix epoll_pwait when EPOLL=nRandy Dunlap
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=7371 sys_epoll_pwait needs to be listed as a conditional (weak) entry point for CONFIG_EPOLL=n. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11[PATCH] lockdep: fix printk recursion logicIngo Molnar
Bug reported and fixed by Tilman Schmidt <tilman@imap.cc>: if lockdep is enabled then log messages make it to /var/log/messages belatedly. The reason is a missed wakeup of klogd. Initially there was only a lockdep_internal() protection against lockdep recursion within vprintk() - it grew the 'outer' lockdep_off()/on() protection only later on. But that lockdep_off() made the release_console_sem() within vprintk() always happen under the lockdep_internal() condition, causing the bug. The right solution to remove the inner protection against recursion here - the outer one is enough. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11[PATCH] lockdep: use BUILD_BUG_ONAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11[PATCH] bitmap: parse input from kernel and user buffersReinette Chatre
lib/bitmap.c:bitmap_parse() is a library function that received as input a user buffer. This seemed to have originated from the way the write_proc function of the /proc filesystem operates. This has been reworked to not use kmalloc and eliminates a lot of get_user() overhead by performing one access_ok before using __get_user(). We need to test if we are in kernel or user space (is_user) and access the buffer differently. We cannot use __get_user() to access kernel addresses in all cases, for example in architectures with separate address space for kernel and user. This function will be useful for other uses as well; for example, taking input for /sysfs instead of /proc, so it was changed to accept kernel buffers. We have this use for the Linux UWB project, as part as the upcoming bandwidth allocator code. Only a few routines used this function and they were changed too. Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com> Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Cc: Paul Jackson <pj@sgi.com> Cc: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11[PATCH] sched: likely profilingNick Piggin
This likely profiling is pretty fun. I found a few possible problems in sched.c. This patch may be not measurable, but when I did measure long ago, nooping (un)likely cost a couple of % on scheduler heavy benchmarks, so it all adds up. Tweak some branch hints: - the 2nd 64 bits in the bitmask is likely to be populated, because it contains the first 28 bits (nearly 3/4) of the normal priorities. (ratio of 669669:691 ~= 1000:1). - it isn't unlikely that context switching switches to another process. it might be very rapidly switching to and from the idle process (ratio of 475815:419004 and 471330:423544). Let the branch predictor decide. - preempt_enable seems to be very often called in a nested preempt_disable or with interrupts disabled (ratio of 3567760:87965 ~= 40:1) Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Daniel Walker <dwalker@mvista.com> Cc: Hua Zhong <hzhong@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>