- 28 5月, 2017 1 次提交
-
-
由 Al Viro 提交于
... and sanitize the ifdefs in there Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
-
- 13 5月, 2017 2 次提交
-
-
由 Martin Liska 提交于
Starting from GCC 7.1, __gcov_exit is a new symbol expected to be implemented in a profiling runtime. [akpm@linux-foundation.org: coding-style fixes] [mliska@suse.cz: v2] Link: http://lkml.kernel.org/r/e63a3c59-0149-c97e-4084-20ca8f146b26@suse.cz Link: http://lkml.kernel.org/r/8c4084fa-3885-29fe-5fc4-0d4ca199c785@suse.czSigned-off-by: NMartin Liska <mliska@suse.cz> Acked-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Deepa Dinamani 提交于
All uses of the current_fs_time() function have been replaced by other time interfaces. And, its use cases can be fulfilled by current_time() or ktime_get_* variants. Link: http://lkml.kernel.org/r/1491613030-11599-13-git-send-email-deepa.kernel@gmail.comSigned-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: NArnd Bergmann <arnd@arndb.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 10 5月, 2017 1 次提交
-
-
由 Will Deacon 提交于
Perf can generate and record a user callchain in response to a synchronous request, such as a tracepoint firing. If this happens under set_fs(KERNEL_DS), then we can end up walking the user stack (and dereferencing/saving whatever we find there) without the protections usually afforded by checks such as access_ok. Rather than play whack-a-mole with each architecture's stack unwinding implementation, fix the root of the problem by ensuring that we force USER_DS when invoking perf_callchain_user from the perf core. Reported-by: NAl Viro <viro@ZenIV.linux.org.uk> Signed-off-by: NWill Deacon <will.deacon@arm.com> Acked-by: NPeter Zijlstra <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NIngo Molnar <mingo@kernel.org>
-
- 09 5月, 2017 15 次提交
-
-
由 Matthias Kaehlcke 提交于
This fixes the following clang warning: kernel/trace/trace.c:3231:12: warning: address of array 'iter->started' will always evaluate to 'true' [-Wpointer-bool-conversion] if (iter->started) Link: http://lkml.kernel.org/r/20170421234110.117075-1-mka@chromium.orgSigned-off-by: NMatthias Kaehlcke <mka@chromium.org> Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
-
由 Deepa Dinamani 提交于
struct timespec is not y2038 safe on 32 bit machines and needs to be replaced by struct timespec64 in order to represent times beyond year 2038 on such machines. Fix all the timestamp representation in struct trace_hwlat and all the corresponding implementations. Link: http://lkml.kernel.org/r/1491613030-11599-3-git-send-email-deepa.kernel@gmail.comSigned-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Acked-by: NSteven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Laura Abbott 提交于
set_memory_* functions have moved to set_memory.h. Switch to this explicitly. Link: http://lkml.kernel.org/r/1488920133-27229-13-git-send-email-labbott@redhat.comSigned-off-by: NLaura Abbott <labbott@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Laura Abbott 提交于
set_memory_* functions have moved to set_memory.h. Switch to this explicitly. Link: http://lkml.kernel.org/r/1488920133-27229-12-git-send-email-labbott@redhat.comSigned-off-by: NLaura Abbott <labbott@redhat.com> Acked-by: NJessica Yu <jeyu@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michal Hocko 提交于
__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.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Reviewed-by: NMatthew 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Dmitry Vyukov 提交于
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.comSigned-off-by: NDmitry 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Zhang Xiao 提交于
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.comSigned-off-by: NZhang Xiao <xiao.zhang@windriver.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Kirill Tkhai 提交于
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.localdomainSigned-off-by: NKirill 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Kirill Tkhai 提交于
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 314a8ad0 ("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.localdomainSigned-off-by: NKirill Tkhai <ktkhai@virtuozzo.com> Acked-by: NCyrill 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Hari Bathini 提交于
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.comSigned-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: NDave Young <dyoung@redhat.com> Acked-by: NTony 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Hari Bathini 提交于
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.comSigned-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com> Acked-by: NDave 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Hoeun Ryu 提交于
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.comSigned-off-by: NHoeun Ryu <hoeun.ryu@gmail.com> Reviewed-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NMichal 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Tetsuo Handa 提交于
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 b2d4c2ed ("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.jpSigned-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: NVegard Nossum <vegard.nossum@oracle.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Gao Feng 提交于
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.comSigned-off-by: NGao 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Daniel Borkmann 提交于
The patch fixes two things at once: 1) It checks the env->allow_ptr_leaks and only prints the map address to the log if we have the privileges to do so, otherwise it just dumps 0 as we would when kptr_restrict is enabled on %pK. Given the latter is off by default and not every distro sets it, I don't want to rely on this, hence the 0 by default for unprivileged. 2) Printing of ldimm64 in the verifier log is currently broken in that we don't print the full immediate, but only the 32 bit part of the first insn part for ldimm64. Thus, fix this up as well; it's okay to access, since we verified all ldimm64 earlier already (including just constants) through replace_map_fd_with_map_ptr(). Fixes: 1be7f75d ("bpf: enable non-root eBPF programs") Fixes: cbd35700 ("bpf: verifier (add ability to receive verification log)") Reported-by: NJann Horn <jannh@google.com> Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
-
- 06 5月, 2017 1 次提交
-
-
由 Rafael J. Wysocki 提交于
The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ during suspend-to-idle transitions and, consequently, any events signaled through it wake up the system from that state. However, on some systems some of the events signaled via the ACPI SCI while suspended to idle should not cause the system to wake up. In fact, quite often they should just be discarded. Arguably, systems should not resume entirely on such events, but in order to decide which events really should cause the system to resume and which are spurious, it is necessary to resume up to the point when ACPI SCIs are actually handled and processed, which is after executing dpm_resume_noirq() in the system resume path. For this reasons, add a loop around freeze_enter() in which the platforms can process events signaled via multiplexed IRQ lines like the ACPI SCI and add suspend-to-idle hooks that can be used for this purpose to struct platform_freeze_ops. In the ACPI case, the ->wake hook is used for checking if the SCI has triggered while suspended and deferring the interrupt-induced system wakeup until the events signaled through it are actually processed sufficiently to decide whether or not the system should resume. In turn, the ->sync hook allows all of the relevant event queues to be flushed so as to prevent events from being missed due to race conditions. In addition to that, some ACPI code processing wakeup events needs to be modified to use the "hard" version of wakeup triggers, so that it will cause a system resume to happen on device-induced wakeup events even if the "soft" mechanism to prevent the system from suspending is not enabled (that also helps to catch device-induced wakeup events occurring during suspend transitions in progress). Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
-
- 05 5月, 2017 1 次提交
-
-
由 Daniel Micay 提交于
stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms The stack canary is an 'unsigned long' and should be fully initialized to random data rather than only 32 bits of random data. Signed-off-by: NDaniel Micay <danielmicay@gmail.com> Acked-by: NArjan van de Ven <arjan@linux.intel.com> Acked-by: NRik van Riel <riel@redhat.com> Acked-by: NKees Cook <keescook@chromium.org> Cc: Arjan van Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
- 04 5月, 2017 6 次提交
-
-
由 Steven Rostedt (VMware) 提交于
Dan Carpenter sent a patch to remove a check in ftrace_match_record() because the logic of the code made the check redundant. I looked deeper into the code, and made the following logic table, with the three variables and the result of the original code. modname mod_matches exclude_mod result ------- ----------- ----------- ------ 0 0 0 return 0 0 0 1 func_match 0 1 * < cannot exist > 1 0 0 return 0 1 0 1 func_match 1 1 0 func_match 1 1 1 return 0 Notice that when mod_matches == exclude mod, the result is always to return 0, and when mod_matches != exclude_mod, then the result is to test the function. This means we only need test if mod_matches is equal to exclude_mod. Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
-
由 Dan Carpenter 提交于
We know that "mod_matches" is true here so there is no need to check again. Link: http://lkml.kernel.org/r/20170331152130.GA4947@mwandaSigned-off-by: NDan Carpenter <dan.carpenter@oracle.com> Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
-
由 Amey Telawane 提交于
Strcpy is inherently not safe, and strlcpy() should be used instead. __trace_find_cmdline() uses strcpy() because the comms saved must have a terminating nul character, but it doesn't hurt to add the extra protection of using strlcpy() instead of strcpy(). Link: http://lkml.kernel.org/r/1493806274-13936-1-git-send-email-amit.pundir@linaro.orgSigned-off-by: NAmey Telawane <ameyt@codeaurora.org> [AmitP: Cherry-picked this commit from CodeAurora kernel/msm-3.10 https://source.codeaurora.org/quic/la/kernel/msm-3.10/commit/?id=2161ae9a70b12cf18ac8e5952a20161ffbccb477] Signed-off-by: NAmit Pundir <amit.pundir@linaro.org> [ Updated change log and removed the "- 1" from len parameter ] Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
-
由 Michal Hocko 提交于
GFP_NOFS context is used for the following 5 reasons currently: - to prevent from deadlocks when the lock held by the allocation context would be needed during the memory reclaim - to prevent from stack overflows during the reclaim because the allocation is performed from a deep context already - to prevent lockups when the allocation context depends on other reclaimers to make a forward progress indirectly - just in case because this would be safe from the fs POV - silence lockdep false positives Unfortunately overuse of this allocation context brings some problems to the MM. Memory reclaim is much weaker (especially during heavy FS metadata workloads), OOM killer cannot be invoked because the MM layer doesn't have enough information about how much memory is freeable by the FS layer. In many cases it is far from clear why the weaker context is even used and so it might be used unnecessarily. We would like to get rid of those as much as possible. One way to do that is to use the flag in scopes rather than isolated cases. Such a scope is declared when really necessary, tracked per task and all the allocation requests from within the context will simply inherit the GFP_NOFS semantic. Not only this is easier to understand and maintain because there are much less problematic contexts than specific allocation requests, this also helps code paths where FS layer interacts with other layers (e.g. crypto, security modules, MM etc...) and there is no easy way to convey the allocation context between the layers. Introduce memalloc_nofs_{save,restore} API to control the scope of GFP_NOFS allocation context. This is basically copying memalloc_noio_{save,restore} API we have for other restricted allocation context GFP_NOIO. The PF_MEMALLOC_NOFS flag already exists and it is just an alias for PF_FSTRANS which has been xfs specific until recently. There are no more PF_FSTRANS users anymore so let's just drop it. PF_MEMALLOC_NOFS is now checked in the MM layer and drops __GFP_FS implicitly same as PF_MEMALLOC_NOIO drops __GFP_IO. memalloc_noio_flags is renamed to current_gfp_context because it now cares about both PF_MEMALLOC_NOFS and PF_MEMALLOC_NOIO contexts. Xfs code paths preserve their semantic. kmem_flags_convert() doesn't need to evaluate the flag anymore. This patch shouldn't introduce any functional changes. Let's hope that filesystems will drop direct GFP_NOFS (resp. ~__GFP_FS) usage as much as possible and only use a properly documented memalloc_nofs_{save,restore} checkpoints where they are appropriate. [akpm@linux-foundation.org: fix comment typo, reflow comment] Link: http://lkml.kernel.org/r/20170306131408.9828-5-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Brian Foster <bfoster@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Michal Hocko 提交于
The current implementation of the reclaim lockup detection can lead to false positives and those even happen and usually lead to tweak the code to silence the lockdep by using GFP_NOFS even though the context can use __GFP_FS just fine. See http://lkml.kernel.org/r/20160512080321.GA18496@dastard as an example. ================================= [ INFO: inconsistent lock state ] 4.5.0-rc2+ #4 Tainted: G O --------------------------------- inconsistent {RECLAIM_FS-ON-R} -> {IN-RECLAIM_FS-W} usage. kswapd0/543 [HC0[0]:SC0[0]:HE1:SE1] takes: (&xfs_nondir_ilock_class){++++-+}, at: xfs_ilock+0x177/0x200 [xfs] {RECLAIM_FS-ON-R} state was registered at: mark_held_locks+0x79/0xa0 lockdep_trace_alloc+0xb3/0x100 kmem_cache_alloc+0x33/0x230 kmem_zone_alloc+0x81/0x120 [xfs] xfs_refcountbt_init_cursor+0x3e/0xa0 [xfs] __xfs_refcount_find_shared+0x75/0x580 [xfs] xfs_refcount_find_shared+0x84/0xb0 [xfs] xfs_getbmap+0x608/0x8c0 [xfs] xfs_vn_fiemap+0xab/0xc0 [xfs] do_vfs_ioctl+0x498/0x670 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x12/0x6f CPU0 ---- lock(&xfs_nondir_ilock_class); <Interrupt> lock(&xfs_nondir_ilock_class); *** DEADLOCK *** 3 locks held by kswapd0/543: stack backtrace: CPU: 0 PID: 543 Comm: kswapd0 Tainted: G O 4.5.0-rc2+ #4 Call Trace: lock_acquire+0xd8/0x1e0 down_write_nested+0x5e/0xc0 xfs_ilock+0x177/0x200 [xfs] xfs_reflink_cancel_cow_range+0x150/0x300 [xfs] xfs_fs_evict_inode+0xdc/0x1e0 [xfs] evict+0xc5/0x190 dispose_list+0x39/0x60 prune_icache_sb+0x4b/0x60 super_cache_scan+0x14f/0x1a0 shrink_slab.part.63.constprop.79+0x1e9/0x4e0 shrink_zone+0x15e/0x170 kswapd+0x4f1/0xa80 kthread+0xf2/0x110 ret_from_fork+0x3f/0x70 To quote Dave: "Ignoring whether reflink should be doing anything or not, that's a "xfs_refcountbt_init_cursor() gets called both outside and inside transactions" lockdep false positive case. The problem here is lockdep has seen this allocation from within a transaction, hence a GFP_NOFS allocation, and now it's seeing it in a GFP_KERNEL context. Also note that we have an active reference to this inode. So, because the reclaim annotations overload the interrupt level detections and it's seen the inode ilock been taken in reclaim ("interrupt") context, this triggers a reclaim context warning where it thinks it is unsafe to do this allocation in GFP_KERNEL context holding the inode ilock..." This sounds like a fundamental problem of the reclaim lock detection. It is really impossible to annotate such a special usecase IMHO unless the reclaim lockup detection is reworked completely. Until then it is much better to provide a way to add "I know what I am doing flag" and mark problematic places. This would prevent from abusing GFP_NOFS flag which has a runtime effect even on configurations which have lockdep disabled. Introduce __GFP_NOLOCKDEP flag which tells the lockdep gfp tracking to skip the current allocation request. While we are at it also make sure that the radix tree doesn't accidentaly override tags stored in the upper part of the gfp_mask. Link: http://lkml.kernel.org/r/20170306131408.9828-3-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Suggested-by: NPeter Zijlstra <peterz@infradead.org> Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NVlastimil Babka <vbabka@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Brian Foster <bfoster@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Nikolay Borisov <nborisov@suse.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Nikolay Borisov 提交于
Patch series "scope GFP_NOFS api", v5. This patch (of 7): Commit 21caf2fc ("mm: teach mm by current context info to not do I/O during memory allocation") added the memalloc_noio_(save|restore) functions to enable people to modify the MM behavior by disabling I/O during memory allocation. This was further extended in commit 934f3072 ("mm: clear __GFP_FS when PF_MEMALLOC_NOIO is set"). memalloc_noio_* functions prevent allocation paths recursing back into the filesystem without explicitly changing the flags for every allocation site. However, lockdep hasn't been keeping up with the changes and it entirely misses handling the memalloc_noio adjustments. Instead, it is left to the callers of __lockdep_trace_alloc to call the function after they have shaven the respective GFP flags which can lead to false positives: ================================= [ INFO: inconsistent lock state ] 4.10.0-nbor #134 Not tainted --------------------------------- inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage. fsstress/3365 [HC0[0]:SC0[0]:HE1:SE1] takes: (&xfs_nondir_ilock_class){++++?.}, at: xfs_ilock+0x141/0x230 {IN-RECLAIM_FS-W} state was registered at: __lock_acquire+0x62a/0x17c0 lock_acquire+0xc5/0x220 down_write_nested+0x4f/0x90 xfs_ilock+0x141/0x230 xfs_reclaim_inode+0x12a/0x320 xfs_reclaim_inodes_ag+0x2c8/0x4e0 xfs_reclaim_inodes_nr+0x33/0x40 xfs_fs_free_cached_objects+0x19/0x20 super_cache_scan+0x191/0x1a0 shrink_slab+0x26f/0x5f0 shrink_node+0xf9/0x2f0 kswapd+0x356/0x920 kthread+0x10c/0x140 ret_from_fork+0x31/0x40 irq event stamp: 173777 hardirqs last enabled at (173777): __local_bh_enable_ip+0x70/0xc0 hardirqs last disabled at (173775): __local_bh_enable_ip+0x37/0xc0 softirqs last enabled at (173776): _xfs_buf_find+0x67a/0xb70 softirqs last disabled at (173774): _xfs_buf_find+0x5db/0xb70 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xfs_nondir_ilock_class); <Interrupt> lock(&xfs_nondir_ilock_class); *** DEADLOCK *** 4 locks held by fsstress/3365: #0: (sb_writers#10){++++++}, at: mnt_want_write+0x24/0x50 #1: (&sb->s_type->i_mutex_key#12){++++++}, at: vfs_setxattr+0x6f/0xb0 #2: (sb_internal#2){++++++}, at: xfs_trans_alloc+0xfc/0x140 #3: (&xfs_nondir_ilock_class){++++?.}, at: xfs_ilock+0x141/0x230 stack backtrace: CPU: 0 PID: 3365 Comm: fsstress Not tainted 4.10.0-nbor #134 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 Call Trace: kmem_cache_alloc_node_trace+0x3a/0x2c0 vm_map_ram+0x2a1/0x510 _xfs_buf_map_pages+0x77/0x140 xfs_buf_get_map+0x185/0x2a0 xfs_attr_rmtval_set+0x233/0x430 xfs_attr_leaf_addname+0x2d2/0x500 xfs_attr_set+0x214/0x420 xfs_xattr_set+0x59/0xb0 __vfs_setxattr+0x76/0xa0 __vfs_setxattr_noperm+0x5e/0xf0 vfs_setxattr+0xae/0xb0 setxattr+0x15e/0x1a0 path_setxattr+0x8f/0xc0 SyS_lsetxattr+0x11/0x20 entry_SYSCALL_64_fastpath+0x23/0xc6 Let's fix this by making lockdep explicitly do the shaving of respective GFP flags. Fixes: 934f3072 ("mm: clear __GFP_FS when PF_MEMALLOC_NOIO is set") Link: http://lkml.kernel.org/r/20170306131408.9828-2-mhocko@kernel.orgSigned-off-by: NNikolay Borisov <nborisov@suse.com> Signed-off-by: NMichal Hocko <mhocko@suse.com> Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Brian Foster <bfoster@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 03 5月, 2017 2 次提交
-
-
由 Paul E. McKenney 提交于
Because the rcu_cblist_n_lazy_cbs() just samples the ->len_lazy counter, and because the rcu_cblist structure is quite straightforward, it makes sense to open-code rcu_cblist_n_lazy_cbs(p) as p->len_lazy, cutting out a level of indirection. This commit makes this change. Reported-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org>
-
由 Paul E. McKenney 提交于
Because the rcu_cblist_n_cbs() just samples the ->len counter, and because the rcu_cblist structure is quite straightforward, it makes sense to open-code rcu_cblist_n_cbs(p) as p->len, cutting out a level of indirection. This commit makes this change. Reported-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org>
-
- 02 5月, 2017 11 次提交
-
-
由 Paul E. McKenney 提交于
Because the rcu_cblist_empty() just samples the ->head pointer, and because the rcu_cblist structure is quite straightforward, it makes sense to open-code rcu_cblist_empty(p) as !p->head, cutting out a level of indirection. This commit makes this change. Reported-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org>
-
由 Paul E. McKenney 提交于
This commit creates a new kernel/rcu/rcu_segcblist.c file that contains non-trivial segcblist functions. Trivial functions remain as static inline functions in kernel/rcu/rcu_segcblist.h Reported-by: NLinus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de>
-
由 Paul Moore 提交于
Cong Wang correctly pointed out that the RCU read locking of the auditd_connection struct was wrong, this patch correct this by adopting a more traditional, and correct RCU locking model. This patch is heavily based on an earlier prototype by Cong Wang. Cc: <stable@vger.kernel.org> # 4.11.x- Reported-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Paul Moore 提交于
The audit subsystem implemented its own buffer cache mechanism which is a bit silly these days when we could use the kmem_cache construct. Some credit is due to Florian Westphal for originally proposing that we remove the audit cache implementation in favor of simple kmalloc()/kfree() calls, but I would rather have a dedicated slab cache to ease debugging and future stats/performance work. Cc: Florian Westphal <fw@strlen.de> Reviewed-by: NRichard Guy Briggs <rgb@redhat.com> Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Deepa Dinamani 提交于
struct timespec is not y2038 safe. Audit timestamps are recorded in string format into an audit buffer for a given context. These mark the entry timestamps for the syscalls. Use y2038 safe struct timespec64 to represent the times. The log strings can handle this transition as strings can hold upto 1024 characters. Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: NArnd Bergmann <arnd@arndb.de> Acked-by: NPaul Moore <paul@paul-moore.com> Acked-by: NRichard Guy Briggs <rgb@redhat.com> Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Paul Moore 提交于
This is arguably the right thing to do, and will make it easier when we start supporting multiple audit daemons in different namespaces. Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Paul Moore 提交于
We were setting the portid incorrectly in the netlink message headers, fix that to always be 0 (nlmsg_pid = 0). Signed-off-by: NPaul Moore <paul@paul-moore.com> Reviewed-by: NRichard Guy Briggs <rgb@redhat.com>
-
由 Paul Moore 提交于
There is no reason to have both of these functions, combine the two. Signed-off-by: NPaul Moore <paul@paul-moore.com> Reviewed-by: NRichard Guy Briggs <rgb@redhat.com>
-
由 Elena Reshetova 提交于
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: NElena Reshetova <elena.reshetova@intel.com> Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com> Signed-off-by: NKees Cook <keescook@chromium.org> Signed-off-by: NDavid Windsor <dwindsor@gmail.com> [PM: fix subject line, add #include] Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Elena Reshetova 提交于
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: NElena Reshetova <elena.reshetova@intel.com> Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com> Signed-off-by: NKees Cook <keescook@chromium.org> Signed-off-by: NDavid Windsor <dwindsor@gmail.com> [PM: fix subject line, add #include] Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Richard Guy Briggs 提交于
When a sysadmin wishes to monitor module unloading with a syscall rule such as: -a always,exit -F arch=x86_64 -S delete_module -F key=mod-unload the SYSCALL record doesn't tell us what module was requested for unloading. Use the new KERN_MODULE auxiliary record to record it. The SYSCALL record result code will list the return code. See: https://github.com/linux-audit/audit-kernel/issues/37 https://github.com/linux-audit/audit-kernel/issues/7 https://github.com/linux-audit/audit-kernel/wiki/RFE-Module-Load-Record-FormatSigned-off-by: NRichard Guy Briggs <rgb@redhat.com> Acked-by: NJessica Yu <jeyu@redhat.com> Signed-off-by: NPaul Moore <paul@paul-moore.com>
-