summaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAgeFilesLines
* mm, vmalloc: use __GFP_HIGHMEM implicitlyMichal Hocko2017-05-085-11/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | __vmalloc* allows users to provide gfp flags for the underlying allocation. This API is quite popular $ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l 77 The only problem is that many people are not aware that they really want to give __GFP_HIGHMEM along with other flags because there is really no reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages which are mapped to the kernel vmalloc space. About half of users don't use this flag, though. This signals that we make the API unnecessarily too complex. This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM are simplified and drop the flag. Link: http://lkml.kernel.org/r/20170307141020.29107-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Cristopher Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kcov: simplify interrupt checkDmitry Vyukov2017-05-081-8/+1
| | | | | | | | | | | | | | | | | | | in_interrupt() semantics are confusing and wrong for most users as it also returns true when bh is disabled. Thus we open coded a proper check for interrupts in __sanitizer_cov_trace_pc() with a lengthy explanatory comment. Use the new in_task() predicate instead. Link: http://lkml.kernel.org/r/20170321091026.139655-1-dvyukov@google.com Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: James Morse <james.morse@arm.com> Cc: Alexander Popov <alex.popov@linux.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* taskstats: add e/u/stime for TGID commandZhang Xiao2017-05-081-0/+14
| | | | | | | | | | | | | | The elapsed time, user CPU time and system CPU time for the thread group status request are presently left at zero. Fill these in. [akpm@linux-foundation.org: run ktime_get_ns() a single time] [akpm@linux-foundation.org: include linux/sched/cputime.h for task_cputime()] Link: http://lkml.kernel.org/r/1488508424-12322-1-git-send-email-xiao.zhang@windriver.com Signed-off-by: Zhang Xiao <xiao.zhang@windriver.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pidns: expose task pid_ns_for_children to userspaceKirill Tkhai2017-05-081-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pid_ns_for_children set by a task is known only to the task itself, and it's impossible to identify it from outside. It's a big problem for checkpoint/restore software like CRIU, because it can't correctly handle tasks, that do setns(CLONE_NEWPID) in proccess of their work. This patch solves the problem, and it exposes pid_ns_for_children to ns directory in standard way with the name "pid_for_children": ~# ls /proc/5531/ns -l | grep pid lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid -> pid:[4026531836] lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid_for_children -> pid:[4026532286] Link: http://lkml.kernel.org/r/149201123914.6007.2187327078064239572.stgit@localhost.localdomain Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Andrei Vagin <avagin@virtuozzo.com> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()Kirill Tkhai2017-05-081-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | alloc_pidmap() advances pid_namespace::last_pid. When first pid allocation fails, then next created process will have pid 2 and pid_ns_prepare_proc() won't be called. So, pid_namespace::proc_mnt will never be initialized (not to mention that there won't be a child reaper). I saw crash stack of such case on kernel 3.10: BUG: unable to handle kernel NULL pointer dereference at (null) IP: proc_flush_task+0x8f/0x1b0 Call Trace: release_task+0x3f/0x490 wait_consider_task.part.10+0x7ff/0xb00 do_wait+0x11f/0x280 SyS_wait4+0x7d/0x110 We may fix this by restore of last_pid in 0 or by prohibiting of futher allocations. Since there was a similar issue in Oleg Nesterov's commit 314a8ad0f18a ("pidns: fix free_pid() to handle the first fork failure"). and it was fixed via prohibiting allocation, let's follow this way, and do the same. Link: http://lkml.kernel.org/r/149201021004.4863.6762095011554287922.stgit@localhost.localdomain Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Andrei Vagin <avagin@virtuozzo.com> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ia64: reuse append_elf_note() and final_note() functionsHari Bathini2017-05-082-48/+14
| | | | | | | | | | | | | | | | | | | Get rid of multiple definitions of append_elf_note() & final_note() functions. Reuse these functions compiled under CONFIG_CRASH_CORE Also, define Elf_Word and use it instead of generic u32 or the more specific Elf64_Word. Link: http://lkml.kernel.org/r/149035342324.6881.11667840929850361402.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_COREHari Bathini2017-05-085-407/+456
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and reuse crashkernel parameter for fadump", v4. Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. This patchset removes dependency with CONFIG_KEXEC for crashkernel parameter and vmcoreinfo related code as it can be reused without kexec support. Also, crashkernel parameter is reused instead of fadump_reserve_mem to reserve memory for fadump. The first patch moves crashkernel parameter parsing and vmcoreinfo related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE. The second patch reuses the definitions of append_elf_note() & final_note() functions under CONFIG_CRASH_CORE in IA64 arch code. The third patch removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump) in powerpc. The next patch reuses crashkernel parameter for reserving memory for fadump, instead of the fadump_reserve_mem parameter. This has the advantage of using all syntaxes crashkernel parameter supports, for fadump as well. The last patch updates fadump kernel documentation about use of crashkernel parameter. This patch (of 5): Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. But currently, code related to vmcoreinfo and parsing of crashkernel parameter is built under CONFIG_KEXEC_CORE. This patch introduces CONFIG_CRASH_CORE and moves the above mentioned code under this config, allowing code reuse without dependency on CONFIG_KEXEC. There is no functional change with this patch. Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fork: free vmapped stacks in cache when cpus are offlineHoeun Ryu2017-05-081-0/+23
| | | | | | | | | | | | | | | | | | | | | | | Using virtually mapped stack, kernel stacks are allocated via vmalloc. In the current implementation, two stacks per cpu can be cached when tasks are freed and the cached stacks are used again in task duplications. But the cached stacks may remain unfreed even when cpu are offline. By adding a cpu hotplug callback to free the cached stacks when a cpu goes offline, the pages of the cached stacks are not wasted. Link: http://lkml.kernel.org/r/1487076043-17802-1-git-send-email-hoeun.ryu@gmail.com Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Mateusz Guzik <mguzik@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/hung_task.c: defer showing held locksTetsuo Handa2017-05-081-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | When I was running my testcase which may block hundreds of threads on fs locks, I got lockup due to output from debug_show_all_locks() added by commit b2d4c2edb2e4 ("locking/hung_task: Show all locks"). For example, if 1000 threads were blocked in TASK_UNINTERRUPTIBLE state and 500 out of 1000 threads hold some lock, debug_show_all_locks() from for_each_process_thread() loop will report locks held by 500 threads for 1000 times. This is a too much noise. In order to make sure rcu_lock_break() is called frequently, we should avoid calling debug_show_all_locks() from for_each_process_thread() loop because debug_show_all_locks() effectively calls for_each_process_thread() loop. Let's defer calling debug_show_all_locks() till before panic() or leaving for_each_process_thread() loop. Link: http://lkml.kernel.org/r/1489296834-60436-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* proc/sysctl: fix the int overflow for jiffies conversionGao Feng2017-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | do_proc_dointvec_jiffies_conv() uses LONG_MAX/HZ as the max value to avoid overflow. But actually the *valp is int type, so it still causes overflow. For example, echo 2147483647 > ./sys/net/ipv4/tcp_keepalive_time Then, cat ./sys/net/ipv4/tcp_keepalive_time The output is "-1", it is not expected. Now use INT_MAX/HZ as the max value instead LONG_MAX/HZ to fix it. Link: http://lkml.kernel.org/r/1490109532-9228-1-git-send-email-fgao@ikuai8.com Signed-off-by: Gao Feng <fgao@ikuai8.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'powerpc-4.12-1' of ↵Linus Torvalds2017-05-051-14/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB virtual address space, but a process can request access to the full 512TB by passing a hint to mmap(). - Support for the new Power9 "XIVE" interrupt controller. - TLB flushing optimisations for the radix MMU on Power9. - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface Architecture 2.0". - The ability to configure the mmap randomisation limits at build and runtime. - Several small fixes and cleanups to the kprobes code, as well as support for KPROBES_ON_FTRACE. - Major improvements to handling of system reset interrupts, correctly treating them as NMIs, giving them a dedicated stack and using a new hypervisor call to trigger them, all of which should aid debugging and robustness. - Many fixes and other minor enhancements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi" * tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it powerpc/powernv: Fix TCE kill on NVLink2 powerpc/mm/radix: Drop support for CPUs without lockless tlbie powerpc/book3s/mce: Move add_taint() later in virtual mode powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body powerpc/smp: Document irq enable/disable after migrating IRQs powerpc/mpc52xx: Don't select user-visible RTAS_PROC powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset() powerpc/eeh: Clean up and document event handling functions powerpc/eeh: Avoid use after free in eeh_handle_special_event() cxl: Mask slice error interrupts after first occurrence cxl: Route eeh events to all drivers in cxl_pci_error_detected() cxl: Force context lock during EEH flow powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST powerpc/xmon: Teach xmon oops about radix vectors powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids powerpc/pseries: Enable VFIO powerpc/powernv: Fix iommu table size calculation hook for small tables powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc powerpc: Add arch/powerpc/tools directory ...
| * powerpc/kprobes: Fix handling of function offsets on ABIv2Naveen N. Rao2017-04-201-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 239aeba76409 ("perf powerpc: Fix kprobe and kretprobe handling with kallsyms on ppc64le") changed how we use the offset field in struct kprobe on ABIv2. perf now offsets from the global entry point if an offset is specified and otherwise chooses the local entry point. Fix the same in kernel for kprobe API users. We do this by extending kprobe_lookup_name() to accept an additional parameter to indicate the offset specified with the kprobe registration. If offset is 0, we return the local function entry and return the global entry point otherwise. With: # cd /sys/kernel/debug/tracing/ # echo "p _do_fork" >> kprobe_events # echo "p _do_fork+0x10" >> kprobe_events before this patch: # cat ../kprobes/list c0000000000d0748 k _do_fork+0x8 [DISABLED] c0000000000d0758 k _do_fork+0x18 [DISABLED] c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] and after: # cat ../kprobes/list c0000000000d04c8 k _do_fork+0x8 [DISABLED] c0000000000d04d0 k _do_fork+0x10 [DISABLED] c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] Acked-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * kprobes: Convert kprobe_lookup_name() to a functionNaveen N. Rao2017-04-201-12/+8
| | | | | | | | | | | | | | | | | | | | | | The macro is now pretty long and ugly on powerpc. In the light of further changes needed here, convert it to a __weak variant to be over-ridden with a nicer looking function. Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * kprobes: Skip preparing optprobe if the probe is ftrace-basedMasami Hiramatsu2017-04-201-2/+9
| | | | | | | | | | | | | | | | | | Skip preparing optprobe if the probe is ftrace-based, since anyway, it must not be optimized (or already optimized by ftrace). Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge branch 'for-linus' of ↵Linus Torvalds2017-05-053-4/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "This is a set of small fixes that were mostly stumbled over during more significant development. This proc fix and the fix to posix-timers are the most significant of the lot. There is a lot of good development going on but unfortunately it didn't quite make the merge window" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: Fix unbalanced hard link numbers signal: Make kill_proc_info static rlimit: Properly call security_task_setrlimit signal: Remove unused definition of sig_user_definied ia64: Remove unused IA64_TASK_SIGHAND_OFFSET and IA64_SIGHAND_SIGLOCK_OFFSET ipc: Remove unused declaration of recompute_msgmni posix-timers: Correct sanity check in posix_cpu_nsleep sysctl: Remove dead register_sysctl_root
| * | signal: Make kill_proc_info staticEric W. Biederman2017-04-211-1/+1
| | | | | | | | | | | | | | | | | | | | | There are no users outside of signal.c so make the function static so the compiler and other developers have that information. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | rlimit: Properly call security_task_setrlimitEric W. Biederman2017-04-211-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify do_prlimit to call security_task_setrlimit passing the task whose rlimit we are changing not the tsk->group_leader. In general this should not matter as the lsms implementing security_task_setrlimit apparmor and selinux both examine the task->cred to see what should be allowed on the destination task. That task->cred is shared between tasks created with CLONE_THREAD unless thread keyrings are in play, in which case both apparmor and selinux create duplicate security contexts. So the only time when it will matter which thread is passed to security_task_setrlimit is if one of the threads of a process performs an operation that changes only it's credentials. At which point if a thread has done that we don't want to hide that information from the lsms. So fix the call of security_task_setrlimit. With the removal of tsk->group_leader this makes the code slightly faster, more comprehensible and maintainable. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | posix-timers: Correct sanity check in posix_cpu_nsleepEric W. Biederman2017-04-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | CPUCLOCK_PID(which_clock) is a pid value from userspace so compare it against task_pid_vnr, not current->pid. As task_pid_vnr is in the tasks pid value in the tasks pid namespace, and current->pid is in the initial pid namespace. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | | Merge tag 'modules-for-v4.12' of ↵Linus Torvalds2017-05-031-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: - Minor code cleanups - Fix section alignment for .init_array * tag 'modules-for-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: kallsyms: Use bounded strnchr() when parsing string module: Unify the return value type of try_module_get module: set .init_array alignment to 8
| * | | kallsyms: Use bounded strnchr() when parsing stringNaveen N. Rao2017-04-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When parsing for the <module:name> format, we use strchr() to look for the separator, when we know that the module name can't be longer than MODULE_NAME_LEN. Enforce the same using strnchr(). Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Jessica Yu <jeyu@redhat.com>
* | | | Merge tag 'trace-v4.12' of ↵Linus Torvalds2017-05-0312-585/+1303
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New features for this release: - Pretty much a full rewrite of the processing of function plugins. i.e. echo do_IRQ:stacktrace > set_ftrace_filter - The rewrite was needed to add plugins to be unique to tracing instances. i.e. mkdir instance/foo; cd instances/foo; echo do_IRQ:stacktrace > set_ftrace_filter The old way was written very hacky. This removes a lot of those hacks. - New "function-fork" tracing option. When set, pids in the set_ftrace_pid will have their children added when the processes with their pids listed in the set_ftrace_pid file forks. - Exposure of "maxactive" for kretprobe in kprobe_events - Allow for builtin init functions to be traced by the function tracer (via the kernel command line). Module init function tracing will come in the next release. - Added more selftests, and have selftests also test in an instance" * tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (60 commits) ring-buffer: Return reader page back into existing ring buffer selftests: ftrace: Allow some event trigger tests to run in an instance selftests: ftrace: Have some basic tests run in a tracing instance too selftests: ftrace: Have event tests also run in an tracing instance selftests: ftrace: Make func_event_triggers and func_traceonoff_triggers tests do instances selftests: ftrace: Allow some tests to be run in a tracing instance tracing/ftrace: Allow for instances to trigger their own stacktrace probes tracing/ftrace: Allow for the traceonoff probe be unique to instances tracing/ftrace: Enable snapshot function trigger to work with instances tracing/ftrace: Allow instances to have their own function probes tracing/ftrace: Add a better way to pass data via the probe functions ftrace: Dynamically create the probe ftrace_ops for the trace_array tracing: Pass the trace_array into ftrace_probe_ops functions tracing: Have the trace_array hold the list of registered func probes ftrace: If the hash for a probe fails to update then free what was initialized ftrace: Have the function probes call their own function ftrace: Have each function probe use its own ftrace_ops ftrace: Have unregister_ftrace_function_probe_func() return a value ftrace: Add helper function ftrace_hash_move_and_update_ops() ftrace: Remove data field from ftrace_func_probe structure ...
| * | | | ring-buffer: Return reader page back into existing ring bufferSteven Rostedt (VMware)2017-05-013-9/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When reading the ring buffer for consuming, it is optimized for splice, where a page is taken out of the ring buffer (zero copy) and sent to the reading consumer. When the read is finished with the page, it calls ring_buffer_free_read_page(), which simply frees the page. The next time the reader needs to get a page from the ring buffer, it must call ring_buffer_alloc_read_page() which allocates and initializes a reader page for the ring buffer to be swapped into the ring buffer for a new filled page for the reader. The problem is that there's no reason to actually free the page when it is passed back to the ring buffer. It can hold it off and reuse it for the next iteration. This completely removes the interaction with the page_alloc mechanism. Using the trace-cmd utility to record all events (causing trace-cmd to require reading lots of pages from the ring buffer, and calling ring_buffer_alloc/free_read_page() several times), and also assigning a stack trace trigger to the mm_page_alloc event, we can see how many times the ring_buffer_alloc_read_page() needed to allocate a page for the ring buffer. Before this change: # trace-cmd record -e all -e mem_page_alloc -R stacktrace sleep 1 # trace-cmd report |grep ring_buffer_alloc_read_page | wc -l 9968 After this change: # trace-cmd record -e all -e mem_page_alloc -R stacktrace sleep 1 # trace-cmd report |grep ring_buffer_alloc_read_page | wc -l 4 Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing/ftrace: Allow for instances to trigger their own stacktrace probesSteven Rostedt (VMware)2017-04-201-3/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Have the stacktrace function trigger probe trigger stack traces within the instance that they were added to in the set_ftrace_filter. ># cd /sys/kernel/debug/tracing ># mkdir instances/foo ># cd instances/foo ># echo schedule:stacktrace:1 > set_ftrace_filter ># cat trace # tracer: nop # # entries-in-buffer/entries-written: 1/1 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <idle>-0 [001] .N.2 202.585010: <stack trace> => => schedule => schedule_preempt_disabled => do_idle => cpu_startup_entry => start_secondary => verify_cpu Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing/ftrace: Allow for the traceonoff probe be unique to instancesSteven Rostedt (VMware)2017-04-203-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Have the traceon/off function probe triggers affect only the instance they are set in. This required making the trace_on/off accessible for other files in the tracing directory. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing/ftrace: Enable snapshot function trigger to work with instancesSteven Rostedt (VMware)2017-04-201-19/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modify the snapshot probe trigger to work with instances. This way the snapshot function trigger will only affect the instance that it is added to in the set_ftrace_filter file. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing/ftrace: Allow instances to have their own function probesSteven Rostedt (VMware)2017-04-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass around the local trace_array that is the descriptor for tracing instances, when enabling and disabling probes. This by default sets the enable/disable of event probe triggers to work with instances. The other probes will need some more work to get them working with instances. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing/ftrace: Add a better way to pass data via the probe functionsSteven Rostedt (VMware)2017-04-205-107/+153
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the redesign of the registration and execution of the function probes (triggers), data can now be passed from the setup of the probe to the probe callers that are specific to the trace_array it is on. Although, all probes still only affect the toplevel trace array, this change will allow for instances to have their own probes separated from other instances and the top array. That is, something like the stacktrace probe can be set to trace only in an instance and not the toplevel trace array. This isn't implement yet, but this change sets the ground work for the change. When a probe callback is triggered (someone writes the probe format into set_ftrace_filter), it calls register_ftrace_function_probe() passing in init_data that will be used to initialize the probe. Then for every matching function, register_ftrace_function_probe() will call the probe_ops->init() function with the init data that was passed to it, as well as an address to a place holder that is associated with the probe and the instance. The first occurrence will have a NULL in the pointer. The init() function will then initialize it. If other probes are added, or more functions are part of the probe, the place holder will be passed to the init() function with the place holder data that it was initialized to the last time. Then this place_holder is passed to each of the other probe_ops functions, where it can be used in the function callback. When the probe_ops free() function is called, it can be called either with the rip of the function that is being removed from the probe, or zero, indicating that there are no more functions attached to the probe, and the place holder is about to be freed. This gives the probe_ops a way to free the data it assigned to the place holder if it was allocade during the first init call. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Dynamically create the probe ftrace_ops for the trace_arraySteven Rostedt (VMware)2017-04-205-57/+146
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to eventually have each trace_array instance have its own unique set of function probes (triggers), the trace array needs to hold the ops and the filters for the probes. This is the first step to accomplish this. Instead of having the private data of the probe ops point to the trace_array, create a separate list that the trace_array holds. There's only one private_data for a probe, we need one per trace_array. The probe ftrace_ops will be dynamically created for each instance, instead of being static. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing: Pass the trace_array into ftrace_probe_ops functionsSteven Rostedt (VMware)2017-04-205-30/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass the trace_array associated to a ftrace_probe_ops into the probe_ops func(), init() and free() functions. The trace_array is the descriptor that describes a tracing instance. This will help create the infrastructure that will allow having function probes unique to tracing instances. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing: Have the trace_array hold the list of registered func probesSteven Rostedt (VMware)2017-04-205-30/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a link list to the trace_array to hold func probes that are registered. Currently, all function probes are the same for all instances as it was before, that is, only the top level trace_array holds the function probes. But this lays the ground work to have function probes be attached to individual instances, and having the event trigger only affect events in the given instance. But that work is still to be done. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: If the hash for a probe fails to update then free what was initializedSteven Rostedt (VMware)2017-04-201-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the ftrace_hash_move_and_update_ops() fails, and an ops->free() function exists, then it needs to be called on all the ops that were added by this registration. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Have the function probes call their own functionSteven Rostedt (VMware)2017-04-202-127/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the function probes have their own ftrace_ops, there's no reason to continue using the ftrace_func_hash to find which probe to call in the function callback. The ops that is passed in to the function callback is part of the probe_ops to call. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Have each function probe use its own ftrace_opsSteven Rostedt (VMware)2017-04-202-148/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Have the function probes have their own ftrace_ops, and remove the trace_probe_ops. This simplifies some of the ftrace infrastructure code. Individual entries for each function is still allocated for the use of the output for set_ftrace_filter, but they will be removed soon too. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Have unregister_ftrace_function_probe_func() return a valueSteven Rostedt (VMware)2017-04-205-14/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently unregister_ftrace_function_probe_func() is a void function. It does not give any feedback if an error occurred or no item was found to remove and nothing was done. Change it to return status and success if it removed something. Also update the callers to return that feedback to the user. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Add helper function ftrace_hash_move_and_update_ops()Steven Rostedt (VMware)2017-04-201-52/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The processes of updating a ops filter_hash is a bit complex, and requires setting up an old hash to perform the update. This is done exactly the same in two locations for the same reasons. Create a helper function that does it in one place. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Remove data field from ftrace_func_probe structureSteven Rostedt (VMware)2017-04-205-15/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No users of the function probes uses the data field anymore. Remove it, and change the init function to take a void *data parameter instead of a void **data, because the init will just get the data that the registering function was received, and there's no state after it is called. The other functions for ftrace_probe_ops still take the data parameter, but it will currently only be passed NULL. It will stay as a parameter for future data to be passed to these functions. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Remove printing of data in showing of a function probeSteven Rostedt (VMware)2017-04-201-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | None of the probe users uses the data field anymore of the entry. They all have their own print() function. Remove showing the data field in the generic function as the data field will be going away. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Remove unused unregister_ftrace_function_probe_all() functionSteven Rostedt (VMware)2017-04-202-20/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are no users of unregister_ftrace_function_probe_all(). The only probe function that is used is unregister_ftrace_function_probe_func(). Rename the internal static function __unregister_ftrace_function_probe() to unregister_ftrace_function_probe_func() and make it global. Also remove the PROBE_TEST_FUNC as it would be always set. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Remove unused unregister_ftrace_function_probe() functionSteven Rostedt (VMware)2017-04-202-18/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nothing calls unregister_ftrace_function_probe(). Remove it as well as the flag PROBE_TEST_DATA, as this function was the only one to set it. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Convert the rest of the function trigger over to the mapping functionsSteven Rostedt (VMware)2017-04-201-38/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the data pointer for individual ips will soon be removed and no longer passed to the callback function probe handlers, convert the rest of the function trigger counters over to the new ftrace_func_mapper helper functions. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing: Have the snapshot trigger use the mapping helper functionsSteven Rostedt (VMware)2017-04-201-8/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the data pointer for individual ips will soon be removed and no longer passed to the callback function probe handlers, convert the snapshot trigger counter over to the new ftrace_func_mapper helper functions. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Added ftrace_func_mapper for function probe triggersSteven Rostedt (VMware)2017-04-203-15/+210
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to move the ops to the function probes directly, they need a way to map function ips to their own data without depending on the infrastructure of the function probes, as the data field will be going away. New helper functions are added that are based on the ftrace_hash code. ftrace_func_mapper functions are there to let the probes map ips to their data. These can be allocated by the probe ops, and referenced in the function callbacks. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Pass probe ops to probe functionSteven Rostedt (VMware)2017-04-205-14/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation to cleaning up the probe function registration code, the "data" parameter will eventually be removed from the probe->func() call. Instead it will receive its own "ops" function, in which it can set up its own data that it needs to map. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Remove unused "flags" field from struct ftrace_func_probeSteven Rostedt (VMware)2017-04-201-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nothing uses "flags" in the ftrace_func_probe descriptor. Remove it. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Move the function commands into the tracing directorySteven Rostedt (VMware)2017-04-201-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As nothing outside the tracing directory uses the function command mechanism, I'm moving the prototypes out of the include/linux/ftrace.h and into the local kernel/trace/trace.h header. I plan on making them hook to the trace_array structure which is local to kernel/trace, and I do not want to expose it to the rest of the kernel. This requires that the command functions must also be local to tracing. But luckily nothing else uses them. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Move the probe function into the tracing directorySteven Rostedt (VMware)2017-04-181-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As nothing outside the tracing directory uses the function probes mechanism, I'm moving the prototypes out of the include/linux/ftrace.h and into the local kernel/trace/trace.h header. I plan on making them hook to the trace_array structure which is local to kernel/trace, and I do not want to expose it to the rest of the kernel. This requires that the probe functions must also be local to tracing. But luckily nothing else uses them. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Add 'function-fork' trace optionNamhyung Kim2017-04-173-2/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function-fork option is same as event-fork that it tracks task fork/exit and set the pid filter properly. This can be useful if user wants to trace selected tasks including their children only. Link: http://lkml.kernel.org/r/20170417024430.21194-3-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | tracing: Have the trace_event benchmark thread call cond_resched_rcu_qs()Steven Rostedt (VMware)2017-04-171-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The trace_event benchmark thread runs in kernel space in an infinite loop while also calling cond_resched() in case anything else wants to schedule in. Unfortunately, on a PREEMPT kernel, that makes it a nop, in which case, this will never voluntarily schedule. That will cause synchronize_rcu_tasks() to forever block on this thread, while it is running. This is exactly what cond_resched_rcu_qs() is for. Use that instead. Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Fix indexing of t_hash_start() from t_next()Steven Rostedt (VMware)2017-04-171-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | t_hash_start() does not increment *pos, where as t_next() must. But when t_next() does increment *pos, it must still pass in the original *pos to t_hash_start() otherwise it will skip the first instance: # cd /sys/kernel/debug/tracing # echo schedule:traceoff > set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter # echo call_rcu > set_ftrace_filter # cat set_ftrace_filter call_rcu schedule:traceoff:unlimited do_IRQ:traceoff:unlimited The above called t_hash_start() from t_start() as there was only one function (call_rcu), but if we add another function: # echo xfrm_policy_destroy_rcu >> set_ftrace_filter # cat set_ftrace_filter call_rcu xfrm_policy_destroy_rcu do_IRQ:traceoff:unlimited The "schedule:traceoff" disappears. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | | ftrace: Fix removing of second function probeSteven Rostedt (VMware)2017-04-151-4/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When two function probes are added to set_ftrace_filter, and then one of them is removed, the update to the function locations is not performed, and the record keeping of the function states are corrupted, and causes an ftrace_bug() to occur. This is easily reproducable by adding two probes, removing one, and then adding it back again. # cd /sys/kernel/debug/tracing # echo schedule:traceoff > set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter # echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter # echo do_IRQ:traceoff > set_ftrace_filter Causes: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1098 at kernel/trace/ftrace.c:2369 ftrace_get_addr_curr+0x143/0x220 Modules linked in: [...] CPU: 2 PID: 1098 Comm: bash Not tainted 4.10.0-test+ #405 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 Call Trace: dump_stack+0x68/0x9f __warn+0x111/0x130 ? trace_irq_work_interrupt+0xa0/0xa0 warn_slowpath_null+0x1d/0x20 ftrace_get_addr_curr+0x143/0x220 ? __fentry__+0x10/0x10 ftrace_replace_code+0xe3/0x4f0 ? ftrace_int3_handler+0x90/0x90 ? printk+0x99/0xb5 ? 0xffffffff81000000 ftrace_modify_all_code+0x97/0x110 arch_ftrace_update_code+0x10/0x20 ftrace_run_update_code+0x1c/0x60 ftrace_run_modify_code.isra.48.constprop.62+0x8e/0xd0 register_ftrace_function_probe+0x4b6/0x590 ? ftrace_startup+0x310/0x310 ? debug_lockdep_rcu_enabled.part.4+0x1a/0x30 ? update_stack_state+0x88/0x110 ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320 ? preempt_count_sub+0x18/0xd0 ? mutex_lock_nested+0x104/0x800 ? ftrace_regex_write.isra.43.part.44+0x1d3/0x320 ? __unwind_start+0x1c0/0x1c0 ? _mutex_lock_nest_lock+0x800/0x800 ftrace_trace_probe_callback.isra.3+0xc0/0x130 ? func_set_flag+0xe0/0xe0 ? __lock_acquire+0x642/0x1790 ? __might_fault+0x1e/0x20 ? trace_get_user+0x398/0x470 ? strcmp+0x35/0x60 ftrace_trace_onoff_callback+0x48/0x70 ftrace_regex_write.isra.43.part.44+0x251/0x320 ? match_records+0x420/0x420 ftrace_filter_write+0x2b/0x30 __vfs_write+0xd7/0x330 ? do_loop_readv_writev+0x120/0x120 ? locks_remove_posix+0x90/0x2f0 ? do_lock_file_wait+0x160/0x160 ? __lock_is_held+0x93/0x100 ? rcu_read_lock_sched_held+0x5c/0xb0 ? preempt_count_sub+0x18/0xd0 ? __sb_start_write+0x10a/0x230 ? vfs_write+0x222/0x240 vfs_write+0xef/0x240 SyS_write+0xab/0x130 ? SyS_read+0x130/0x130 ? trace_hardirqs_on_caller+0x182/0x280 ? trace_hardirqs_on_thunk+0x1a/0x1c entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7fe61c157c30 RSP: 002b:00007ffe87890258 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: ffffffff8114a410 RCX: 00007fe61c157c30 RDX: 0000000000000010 RSI: 000055814798f5e0 RDI: 0000000000000001 RBP: ffff8800c9027f98 R08: 00007fe61c422740 R09: 00007fe61ca53700 R10: 0000000000000073 R11: 0000000000000246 R12: 0000558147a36400 R13: 00007ffe8788f160 R14: 0000000000000024 R15: 00007ffe8788f15c ? trace_hardirqs_off_caller+0xc0/0x110 ---[ end trace 99fa09b3d9869c2c ]--- Bad trampoline accounting at: ffffffff81cc3b00 (do_IRQ+0x0/0x150) Cc: stable@vger.kernel.org Fixes: 59df055f1991 ("ftrace: trace different functions with a different tracer") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-29 00:56:04 +0000