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* tracing: Add full state to trace_seqJohannes Berg2009-12-09
| | | | | | | | | | | | | The trace_seq buffer might fill up, and right now one needs to check the return value of each printf into the buffer to check for that. Instead, have the buffer keep track of whether it is full or not, and reject more input if it is full or would have overflowed with an input that wasn't added. Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Buffer the output of seq_file in case of filled bufferSteven Rostedt2009-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the seq_read fills the buffer it will call s_start again on the next itertation with the same position. This causes a problem with the function_graph tracer because it consumes the iteration in order to determine leaf functions. What happens is that the iterator stores the entry, and the function graph plugin will look at the next entry. If that next entry is a return of the same function and task, then the function is a leaf and the function_graph plugin calls ring_buffer_read which moves the ring buffer iterator forward (the trace iterator still points to the function start entry). The copying of the trace_seq to the seq_file buffer will fail if the seq_file buffer is full. The seq_read will not show this entry. The next read by userspace will cause seq_read to again call s_start which will reuse the trace iterator entry (the function start entry). But the function return entry was already consumed. The function graph plugin will think that this entry is a nested function and not a leaf. To solve this, the trace code now checks the return status of the seq_printf (trace_print_seq). If the writing to the seq_file buffer fails, we set a flag in the iterator (leftover) and we do not reset the trace_seq buffer. On the next call to s_start, we check the leftover flag, and if it is set, we just reuse the trace_seq buffer and do not call into the plugin print functions. Before this patch: 2) | fput() { 2) | __fput() { 2) 0.550 us | inotify_inode_queue_event(); 2) | __fsnotify_parent() { 2) 0.540 us | inotify_dentry_parent_queue_event(); After the patch: 2) | fput() { 2) | __fput() { 2) 0.550 us | inotify_inode_queue_event(); 2) 0.548 us | __fsnotify_parent(); 2) 0.540 us | inotify_dentry_parent_queue_event(); [ Updated the patch to fix a missing return 0 from the trace_print_seq() stub when CONFIG_TRACING is disabled. Reported-by: Ingo Molnar <mingo@elte.hu> ] Reported-by: Jiri Olsa <jolsa@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Only call pipe_close if pipe_close is definedSteven Rostedt2009-12-09
| | | | | | | | | This fixes a cut and paste error that had pipe_close get called if pipe_open was defined (not pipe_close). Reported-by: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com> LKML-Reference: <20091209153204.F4CD.A69D9226@jp.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add pipe_close interfaceSteven Rostedt2009-12-07
| | | | | | | | | | An ftrace plugin can add a pipe_open interface when the user opens trace_pipe. But if the plugin allocates something within the pipe_open it can not free it because there exists no pipe_close. The hook to the trace file open has a corresponding close. The closing of the trace_pipe file should also have a corresponding close. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds2009-12-05
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Limit number of per cpu TSC sync messages x86: dumpstack, 64-bit: Disable preemption when walking the IRQ/exception stacks x86: dumpstack: Clean up the x86_stack_ids[][] initalization and other details x86, cpu: mv display_cacheinfo -> cpu_detect_cache_sizes x86: Suppress stack overrun message for init_task x86: Fix cpu_devs[] initialization in early_cpu_init() x86: Remove CPU cache size output for non-Intel too x86: Minimise printk spew from per-vendor init code x86: Remove the CPU cache size printk's cpumask: Avoid cpumask_t in arch/x86/kernel/apic/nmi.c x86: Make sure we also print a Code: line for show_regs()
| * x86: Limit number of per cpu TSC sync messagesMike Travis2009-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Limit the number of per cpu TSC sync messages by only printing to the console if an error occurs, otherwise print as a DEBUG message. The info message "Skipping synchronization ..." is only printed after the last cpu has booted. Signed-off-by: Mike Travis <travis@sgi.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Tejun Heo <tj@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Jack Steiner <steiner@sgi.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091118002222.181053000@alcatraz.americas.sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: dumpstack, 64-bit: Disable preemption when walking the IRQ/exception stacksIngo Molnar2009-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This warning: [ 847.140022] rb_producer D 0000000000000000 5928 519 2 0x00000000 [ 847.203627] BUG: using smp_processor_id() in preemptible [00000000] code: khungtaskd/517 [ 847.207360] caller is show_stack_log_lvl+0x2e/0x241 [ 847.210364] Pid: 517, comm: khungtaskd Not tainted 2.6.32-rc8-tip+ #13761 [ 847.213395] Call Trace: [ 847.215847] [<ffffffff81413bde>] debug_smp_processor_id+0x1f0/0x20a [ 847.216809] [<ffffffff81015eae>] show_stack_log_lvl+0x2e/0x241 [ 847.220027] [<ffffffff81018512>] show_stack+0x1c/0x1e [ 847.223365] [<ffffffff8107b7db>] sched_show_task+0xe4/0xe9 [ 847.226694] [<ffffffff8112f21f>] check_hung_task+0x140/0x199 [ 847.230261] [<ffffffff8112f4a8>] check_hung_uninterruptible_tasks+0x1b7/0x20f [ 847.233371] [<ffffffff8112f500>] ? watchdog+0x0/0x50 [ 847.236683] [<ffffffff8112f54e>] watchdog+0x4e/0x50 [ 847.240034] [<ffffffff810cee56>] kthread+0x97/0x9f [ 847.243372] [<ffffffff81012aea>] child_rip+0xa/0x20 [ 847.246690] [<ffffffff81e43494>] ? restore_args+0x0/0x30 [ 847.250019] [<ffffffff81e43083>] ? _spin_lock+0xe/0x10 [ 847.253351] [<ffffffff810cedbf>] ? kthread+0x0/0x9f [ 847.256833] [<ffffffff81012ae0>] ? child_rip+0x0/0x20 Happens because on preempt-RCU, khungd calls show_stack() with preemption enabled. Make sure we are not preemptible while walking the IRQ and exception stacks on 64-bit. (32-bit stack dumping is preemption safe.) Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: dumpstack: Clean up the x86_stack_ids[][] initalization and other detailsIngo Molnar2009-11-26
| | | | | | | | | | | | | | | | | | | | Make the initialization more readable, plus tidy up a few small visual details as well. No change in functionality. LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86, cpu: mv display_cacheinfo -> cpu_detect_cache_sizesBorislav Petkov2009-11-23
| | | | | | | | | | | | | | | | | | display_cacheinfo() doesn't display anything anymore and it is used to detect CPU cache sizes. Rename it accordingly. Signed-off-by: Borislav Petkov <petkovbb@gmail.com> LKML-Reference: <20091121130145.GA31357@liondog.tnic> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * x86: Suppress stack overrun message for init_taskJan Beulich2009-11-23
| | | | | | | | | | | | | | | | | | | | init_task doesn't get its stack end location set to STACK_END_MAGIC, and hence the message is confusing rather than helpful in this case. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4B06AEFE02000078000211F4@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Fix cpu_devs[] initialization in early_cpu_init()Ingo Molnar2009-11-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Yinghai Lu noticed that this commit: 0388423: x86: Minimise printk spew from per-vendor init code mistakenly left out the initialization of cpu_devs[] in the !PROCESSOR_SELECT case. Fix it. Reported-by: Yinghai Lu <yinghai@kernel.org> Cc: Dave Jones <davej@redhat.com> LKML-Reference: <20091113203000.GA19160@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Remove CPU cache size output for non-Intel tooRoland Dreier2009-11-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Dave Jones said about the output in intel_cacheinfo.c: "They aren't useful, and pollute the dmesg output a lot (especially on machines with many cores). Also the same information can be trivially found out from userspace." Give the generic display_cacheinfo() function the same treatment. Signed-off-by: Roland Dreier <rolandd@cisco.com> Acked-by: Dave Jones <davej@redhat.com> Cc: Mike Travis <travis@sgi.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Tejun Heo <tj@kernel.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Jack Steiner <steiner@sgi.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <adaocn6dp99.fsf_-_@roland-alpha.cisco.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Minimise printk spew from per-vendor init codeDave Jones2009-11-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the default case where the kernel supports all CPU vendors, we currently print out a bunch of not useful messages on every system. 32-bit: KERNEL supported cpus: Intel GenuineIntel AMD AuthenticAMD NSC Geode by NSC Cyrix CyrixInstead Centaur CentaurHauls Transmeta GenuineTMx86 Transmeta TransmetaCPU UMC UMC UMC UMC 64-bit: KERNEL supported cpus: Intel GenuineIntel AMD AuthenticAMD Centaur CentaurHauls Given that "what CPUs does the kernel support" isn't useful for the "support everything" case, we can suppress these printk's. Signed-off-by: Dave Jones <davej@redhat.com> LKML-Reference: <20091113203000.GA19160@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Remove the CPU cache size printk'sDave Jones2009-11-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | They aren't really useful, and they pollute the dmesg output a lot (especially on machines with many cores). Also the same information can be trivially found out from userspace. Reported-by: Mike Travis <travis@sgi.com> Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Tejun Heo <tj@kernel.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Jack Steiner <steiner@sgi.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091112231542.GA7129@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * cpumask: Avoid cpumask_t in arch/x86/kernel/apic/nmi.cRusty Russell2009-11-04
| | | | | | | | | | | | | | | | | | | | | | | | Ingo wants the certainty of a static cpumask (rather than a cpumask_var_t), but cpumask_t will some day be undefined to avoid on-stack declarations. This is what DECLARE_BITMAP/to_cpumask() is for. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> LKML-Reference: <200911031453.52394.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: Make sure we also print a Code: line for show_regs()Arjan van de Ven2009-11-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | show_regs() is called as a mini BUG() equivalent in some places, specifically for the "scheduling while atomic" case. Unfortunately right now it does not print a Code: line unlike a real bug/oops. This patch changes the x86 implementation of show_regs() so that it calls the same function as oopses do to print the registers as well as the Code: line. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20091102165915.4a980fc0@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2009-12-05
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, msr, cpumask: Use struct cpumask rather than the deprecated cpumask_t x86, cpuid: Simplify the code in cpuid_open x86, cpuid: Remove the bkl from cpuid_open() x86, msr: Remove the bkl from msr_open() x86: AMD Geode LX optimizations x86, msr: Unify rdmsr_on_cpus/wrmsr_on_cpus
| * | x86, msr, cpumask: Use struct cpumask rather than the deprecated cpumask_tRusty Russell2009-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes the declarations match the definitions, which already use 'struct cpumask'. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <200911052245.41803.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86, cpuid: Simplify the code in cpuid_openJohn Kacur2009-10-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Peter picked up my patch for tip/x86/cpu that removes the bkl in cpuid_open. Ingo subsequently merged that into tip/master. This patch folds back in tglx's 55968ede164ae523692f00717f50cd926f1382a0 to my patch that removed the bkl. This simplifies the code, and makes it consistent with the changes to kill the bkl in msr.c as well. Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Kacur <jkacur@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, cpuid: Remove the bkl from cpuid_open()John Kacur2009-10-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most of the variables are local to the function. It IS possible that for struct cpuinfo_x86 *c c could point to the same area. However, this is used read only. Signed-off-by: John Kacur <jkacur@redhat.com> LKML-Reference: <alpine.LFD.2.00.0910072016190.15183@localhost.localdomain> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, msr: Remove the bkl from msr_open()Frederic Weisbecker2009-10-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the big kernel lock from msr_open() as it doesn't protect anything there. The only racy event that can happen here is a concurrent cpu shutdown. So let's look at what could be racy during/after the above event: - The cpu_online() check is racy, but the bkl doesn't help about that anyway it disables preemption but we may be chcking another cpu than the current one. Also the cpu can still become offlined between open and read calls. - The cpu_data(cpu) returns a safe pointer too. It won't be released on cpu offlining. But some fields can be changed from arch/x86/kernel/smpboot.c:remove_siblinginfo() : - phys_proc_id - cpu_core_id Those are not read from msr_open(). What we are checking is the x86_capability that is left untouched on offlining. So this removal looks safe. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Kacur <jkacur@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sven-Thorsten Dietrich <sdietrich@suse.de> LKML-Reference: <1254944602-7382-1-git-send-email-fweisbec@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86: AMD Geode LX optimizationsMatteo Croce2009-10-02
| | | | | | | | | | | | | | | | | | | | | | | | Add CPU optimizations for AMD Geode LX. Signed-off-by: Matteo Croce <technoboy85@gmail.com> LKML-Reference: <40101cc30910010811v5d15ff4cx9dd57c9cc9b4b045@mail.gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, msr: Unify rdmsr_on_cpus/wrmsr_on_cpusBorislav Petkov2009-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since rdmsr_on_cpus and wrmsr_on_cpus are almost identical, unify them into a common __rwmsr_on_cpus helper thus avoiding code duplication. While at it, convert cpumask_t's to const struct cpumask *. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2009-12-05
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix a section mismatch in arch/x86/kernel/setup.c x86: Fixup last users of irq_chip->typename x86: Remove BKL from apm_32 x86: Remove BKL from microcode x86: use kernel_stack_pointer() in kprobes.c x86: use kernel_stack_pointer() in kgdb.c x86: use kernel_stack_pointer() in dumpstack.c x86: use kernel_stack_pointer() in process_32.c
| * | | x86: Fix a section mismatch in arch/x86/kernel/setup.cHelight.Xu2009-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | copy_edd() should be __init. warning msg: WARNING: vmlinux.o(.text+0x7759): Section mismatch in reference from the function copy_edd() to the variable .init.data:boot_params The function copy_edd() references the variable __initdata boot_params. This is often because copy_edd lacks a __initdata annotation or the annotation of boot_params is wrong. Signed-off-by: ZhenwenXu <helight.xu@gmail.com> LKML-Reference: <4B139F8F.4000907@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | | x86: Fixup last users of irq_chip->typenameThomas Gleixner2009-11-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The typename member of struct irq_chip was kept for migration purposes and is obsolete since more than 2 years. Fix up the leftovers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | x86: Remove BKL from apm_32Thomas Gleixner2009-10-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The lock/unlock kernel pair in do_open() got there with the BKL push down and protects nothing. Remove it. Replace the lock/unlock kernel in the ioctl code with a mutex to protect standbys_pending and suspends_pending. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <20091010153349.365236337@linutronix.de>
| * | | x86: Remove BKL from microcodeThomas Gleixner2009-10-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cycle_lock_kernel() in microcode_open() is a worthless exercise as there is nothing to wait for. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <20091010153349.196074920@linutronix.de>
| * | | x86: use kernel_stack_pointer() in kprobes.cH. Peter Anvin2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way to obtain a kernel-mode stack pointer from a struct pt_regs in 32-bit mode is "subtle": the stack doesn't actually contain the stack pointer, but rather the location where it would have been marks the actual previous stack frame. For clarity, use kernel_stack_pointer() instead of coding this weirdness explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Masami Hiramatsu <mhiramat@redhat.com>
| * | | x86: use kernel_stack_pointer() in kgdb.cH. Peter Anvin2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way to obtain a kernel-mode stack pointer from a struct pt_regs in 32-bit mode is "subtle": the stack doesn't actually contain the stack pointer, but rather the location where it would have been marks the actual previous stack frame. For clarity, use kernel_stack_pointer() instead of coding this weirdness explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Jason Wessel <jason.wessel@windriver.com>
| * | | x86: use kernel_stack_pointer() in dumpstack.cH. Peter Anvin2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way to obtain a kernel-mode stack pointer from a struct pt_regs in 32-bit mode is "subtle": the stack doesn't actually contain the stack pointer, but rather the location where it would have been marks the actual previous stack frame. For clarity, use kernel_stack_pointer() instead of coding this weirdness explicitly. Furthermore, user_mode() is only valid when the process is known to not run in V86 mode. Use the safer user_mode_vm() instead. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | | x86: use kernel_stack_pointer() in process_32.cH. Peter Anvin2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way to obtain a kernel-mode stack pointer from a struct pt_regs in 32-bit mode is "subtle": the stack doesn't actually contain the stack pointer, but rather the location where it would have been marks the actual previous stack frame. For clarity, use kernel_stack_pointer() instead of coding this weirdness explicitly. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | | | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2009-12-05
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: include/linux/compiler-gcc4.h: Fix build bug - gcc-4.0.2 doesn't understand __builtin_object_size x86/alternatives: No need for alternatives-asm.h to re-invent stuff already in asm.h x86/alternatives: Check replacementlen <= instrlen at build time x86, 64-bit: Set data segments to null after switching to 64-bit mode x86: Clean up the loadsegment() macro x86: Optimize loadsegment() x86: Add missing might_fault() checks to copy_{to,from}_user() x86-64: __copy_from_user_inatomic() adjustments x86: Remove unused thread_return label from switch_to() x86, 64-bit: Fix bstep_iret jump x86: Don't use the strict copy checks when branch profiling is in use x86, 64-bit: Move K8 B step iret fixup to fault entry asm x86: Generate cmpxchg build failures x86: Add a Kconfig option to turn the copy_from_user warnings into errors x86: Turn the copy_from_user check into an (optional) compile time warning x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy x86: Use __builtin_object_size() to validate the buffer size for copy_from_user()
| * | | | include/linux/compiler-gcc4.h: Fix build bug - gcc-4.0.2 doesn't understand ↵Andrew Morton2009-12-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __builtin_object_size Maybe 4.1.0 doesn't too, but this fixed it for me. Caused by: 4a31276: x86: Turn the copy_from_user check into an (optional) compile time warning 9f0cf4a: x86: Use __builtin_object_size() to validate the buffer size for copy_from_user() Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <200910090724.n997OQl6013538@imap1.linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86/alternatives: No need for alternatives-asm.h to re-invent stuff already ↵Jan Beulich2009-12-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | in asm.h This at once also gets the alignment specification right for x86-64. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4B0FF8F80200007800022708@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86/alternatives: Check replacementlen <= instrlen at build timeJan Beulich2009-12-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having run into the run-(boot-)time check a couple of times lately, I finally took time to find a build-time check so that one doesn't need to analyze the register/stack dump and resolve this (through manual lookup in vmlinux) to the offending construct. The assembler will emit a message like "Error: value of <num> too large for field of 1 bytes at <offset>", which while not pointing out the source location still makes analysis quite a bit easier. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4B0FF8AA0200007800022703@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86, 64-bit: Set data segments to null after switching to 64-bit modeBrian Gerst2009-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This prevents kernel threads from inheriting non-null segment selectors, and causing optimizations in __switch_to() to be ineffective. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Tim Blechmann <tim@klingt.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jan Beulich <JBeulich@novell.com> LKML-Reference: <1259165856-3512-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Clean up the loadsegment() macroIngo Molnar2009-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it readable in the source too, not just in the assembly output. No change in functionality. Cc: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1259176706-5908-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Optimize loadsegment()Brian Gerst2009-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Zero the input register in the exception handler instead of using an extra register to pass in a zero value. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1259176706-5908-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Add missing might_fault() checks to copy_{to,from}_user()Frederic Weisbecker2009-11-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86-64, copy_[to|from]_user() rely on assembly routines that never call might_fault(), making us missing various lockdep checks. This doesn't apply to __copy_from,to_user() that explicitly handle these calls, neither is it a problem in x86-32 where copy_to,from_user() rely on the "__" prefixed versions that also call might_fault(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258382538-30979-1-git-send-email-fweisbec@gmail.com> [ v2: fix module export ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86-64: __copy_from_user_inatomic() adjustmentsJan Beulich2009-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This v2.6.26 commit: ad2fc2c: x86: fix copy_user on x86 rendered __copy_from_user_inatomic() identical to copy_user_generic(), yet didn't make the former just call the latter from an inline function. Furthermore, this v2.6.19 commit: b885808: [PATCH] Add proper sparse __user casts to __copy_to_user_inatomic converted the return type of __copy_to_user_inatomic() from unsigned long to int, but didn't do the same to __copy_from_user_inatomic(). Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: <v.mayatskih@gmail.com> LKML-Reference: <4AFD5778020000780001F8F4@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Remove unused thread_return label from switch_to()Masami Hiramatsu2009-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unused thread_return label from switch_to() macro on x86-64. Since this symbol cuts into schedule(), backtrace at the latter half of schedule() was always shown as thread_return(). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091105160359.5181.26225.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86, 64-bit: Fix bstep_iret jumpBrian Gerst2009-11-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This jump should be unconditional. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1257274925-15713-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Don't use the strict copy checks when branch profiling is in useArjan van de Ven2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The branch profiling creates very complex code for each if statement, to the point that gcc has trouble even analyzing something as simple as if (count > 5) count = 5; This then means that causing an error on code that gcc cannot analyze for copy_from_user() and co is not very productive. This patch excludes the strict copy checks in the case of branch profiling being enabled. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <20091006070452.5e1fc119@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86, 64-bit: Move K8 B step iret fixup to fault entry asmBrian Gerst2009-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the handling of truncated %rip from an iret fault to the fault entry path. This allows x86-64 to use the standard search_extable() function. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jan Beulich <jbeulich@novell.com> LKML-Reference: <1255357103-5418-1-git-send-email-brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Generate cmpxchg build failuresPeter Zijlstra2009-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rework the x86 cmpxchg() implementation to generate build failures when used on improper types. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1254771187.21044.22.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Add a Kconfig option to turn the copy_from_user warnings into errorsArjan van de Ven2009-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For automated testing it is useful to have the option to turn the warnings on copy_from_user() etc checks into errors: In function ‘copy_from_user’, inlined from ‘fd_copyin’ at drivers/block/floppy.c:3080, inlined from ‘fd_ioctl’ at drivers/block/floppy.c:3503: linux/arch/x86/include/asm/uaccess_32.h:213: error: call to ‘copy_from_user_overflow’ declared with attribute error: copy_from_user buffer size is not provably correct Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20091002075050.4e9f7641@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Turn the copy_from_user check into an (optional) compile time warningArjan van de Ven2009-10-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A previous patch added the buffer size check to copy_from_user(). One of the things learned from analyzing the result of the previous patch is that in general, gcc is really good at proving that the code contains sufficient security checks to not need to do a runtime check. But that for those cases where gcc could not prove this, there was a relatively high percentage of real security issues. This patch turns the case of "gcc cannot prove" into a compile time warning, as long as a sufficiently new gcc is in use that supports this. The objective is that these warnings will trigger developers checking new cases out before a security hole enters a linux kernel release. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Cc: Jan Beulich <jbeulich@novell.com> LKML-Reference: <20090930130523.348ae6c4@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: Use __builtin_memset and __builtin_memcpy for memset/memcpyArjan van de Ven2009-09-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC provides reasonable memset/memcpy functions itself, with __builtin_memset and __builtin_memcpy. For the "unknown" cases, it'll fall back to our current existing functions, but for fixed size versions it'll inline something smart. Quite often that will be the same as we have now, but sometimes it can do something smarter (for example, if the code then sets the first member of a struct, it can do a shorter memset). In addition, and this is more important, gcc knows which registers and such are not clobbered (while for our asm version it pretty much acts like a compiler barrier), so for various cases it can avoid reloading values. The effect on codesize is shown below on my typical laptop .config: text data bss dec hex filename 5605675 2041100 6525148 14171923 d83f13 vmlinux.before 5595849 2041668 6525148 14162665 d81ae9 vmlinux.after Due to some not-so-good behavior in the gcc 3.x series, this change is only done for GCC 4.x and above. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20090928142122.6fc57e9c@infradead.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | | | x86: Use __builtin_object_size() to validate the buffer size for ↵Arjan van de Ven2009-09-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | copy_from_user() gcc (4.x) supports the __builtin_object_size() builtin, which reports the size of an object that a pointer point to, when known at compile time. If the buffer size is not known at compile time, a constant -1 is returned. This patch uses this feature to add a sanity check to copy_from_user(); if the target buffer is known to be smaller than the copy size, the copy is aborted and a WARNing is emitted in memory debug mode. These extra checks compile away when the object size is not known, or if both the buffer size and the copy length are constants. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20090926143301.2c396b94@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>