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2016-10-07min/max: remove sparse warnings when they're nestedJohannes Berg
Currently, when min/max are nested within themselves, sparse will warn: warning: symbol '_min1' shadows an earlier one originally declared here warning: symbol '_min1' shadows an earlier one originally declared here warning: symbol '_min2' shadows an earlier one originally declared here This also immediately happens when min3() or max3() are used. Since sparse implements __COUNTER__, we can use __UNIQUE_ID() to generate unique variable names, avoiding this. Link: http://lkml.kernel.org/r/1471519773-29882-1-git-send-email-johannes@sipsolutions.net Signed-off-by: Johannes Berg <johannes.berg@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-22sched/core: Optimize __schedule()Peter Zijlstra
Oleg noted that by making do_exit() use __schedule() for the TASK_DEAD context switch, we can avoid the TASK_DEAD special case currently in __schedule() because that avoids the extra preempt_disable() from schedule(). In order to facilitate this, create a do_task_dead() helper which we place in the scheduler code, such that it can access __schedule(). Also add some __noreturn annotations to the functions, there's no coming back from do_exit(). Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Cheng Chao <cs.os.kernel@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: chris@chris-wilson.co.uk Cc: tj@kernel.org Link: http://lkml.kernel.org/r/20160913163729.GB5012@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-02dynamic_debug: only add header when usedLuis de Bethencourt
kernel.h header doesn't directly use dynamic debug, instead we can include it in module.c (which used it via kernel.h). printk.h only uses it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen in that case. Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com [luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h] Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-15rcu: sysctl: Panic on RCU StallDaniel Bristot de Oliveira
It is not always easy to determine the cause of an RCU stall just by analysing the RCU stall messages, mainly when the problem is caused by the indirect starvation of rcu threads. For example, when preempt_rcu is not awakened due to the starvation of a timer softirq. We have been hard coding panic() in the RCU stall functions for some time while testing the kernel-rt. But this is not possible in some scenarios, like when supporting customers. This patch implements the sysctl kernel.panic_on_rcu_stall. If set to 1, the system will panic() when an RCU stall takes place, enabling the capture of a vmcore. The vmcore provides a way to analyze all kernel/tasks states, helping out to point to the culprit and the solution for the stall. The kernel.panic_on_rcu_stall sysctl is disabled by default. Changes from v1: - Fixed a typo in the git log - The if(sysctl_panic_on_rcu_stall) panic() is in a static function - Fixed the CONFIG_TINY_RCU compilation issue - The var sysctl_panic_on_rcu_stall is now __read_mostly Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-05-20Merge tag 'staging-4.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging and IIO driver updates from Greg KH: "Here's the big staging and iio driver update for 4.7-rc1. I think we almost broke even with this release, only adding a few more lines than we removed, which isn't bad overall given that there's a bunch of new iio drivers added. The Lustre developers seem to have woken up from their sleep and have been doing a great job in cleaning up the code and pruning unused or old cruft, the filesystem is almost readable :) Other than that, just a lot of basic coding style cleanups in the churn. All have been in linux-next for a while with no reported issues" * tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (938 commits) Staging: emxx_udc: emxx_udc: fixed coding style issue staging/gdm724x: fix "alignment should match open parenthesis" issues staging/gdm724x: Fix avoid CamelCase staging: unisys: rename misleading var ii with frag staging: unisys: visorhba: switch success handling to error handling staging: unisys: visorhba: main path needs to flow down the left margin staging: unisys: visorinput: handle_locking_key() simplifications staging: unisys: visorhba: fail gracefully for thread creation failures staging: unisys: visornic: comment restructuring and removing bad diction staging: unisys: fix format string %Lx to %llx for u64 staging: unisys: remove unused struct members staging: unisys: visorchannel: correct variable misspelling staging: unisys: visorhba: replace functionlike macro with function staging: dgnc: Need to check for NULL of ch staging: dgnc: remove redundant condition check staging: dgnc: fix 'line over 80 characters' staging: dgnc: clean up the dgnc_get_modem_info() staging: lustre: lnet: enable configuration per NI interface staging: lustre: o2iblnd: properly set ibr_why staging: lustre: o2iblnd: remove last of kiblnd_tunables_fini ...
2016-05-19include/linux: apply __malloc attributeRasmus Villemoes
Attach the malloc attribute to a few allocation functions. This helps gcc generate better code by telling it that the return value doesn't alias any existing pointers (which is even more valuable given the pessimizations implied by -fno-strict-aliasing). A simple example of what this allows gcc to do can be seen by looking at the last part of drm_atomic_helper_plane_reset: plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL); if (plane->state) { plane->state->plane = plane; plane->state->rotation = BIT(DRM_ROTATE_0); } which compiles to e8 99 bf d6 ff callq ffffffff8116d540 <kmem_cache_alloc_trace> 48 85 c0 test %rax,%rax 48 89 83 40 02 00 00 mov %rax,0x240(%rbx) 74 11 je ffffffff814015c4 <drm_atomic_helper_plane_reset+0x64> 48 89 18 mov %rbx,(%rax) 48 8b 83 40 02 00 00 mov 0x240(%rbx),%rax [*] c7 40 40 01 00 00 00 movl $0x1,0x40(%rax) With this patch applied, the instruction at [*] is elided, since the store to plane->state->plane is known to not alter the value of plane->state. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-29kernel.h: add u64_to_user_ptr()Gustavo Padovan
This function had copies in 3 different files. Unify them in kernel.h. Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Rob Clark <robdclark@gmail.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Acked-by: Daniel Vetter <daniel.vetter@intel.com> [drm/i915/] Acked-by: Rob Clark <robdclark@gmail.com> [drm/msm/] Acked-by: Lucas Stach <l.stach@pengutronix.de> [drm/etinav/] Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-24Merge tag 'trace-v4.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Nothing major this round. Mostly small clean ups and fixes. Some visible changes: - A new flag was added to distinguish traces done in NMI context. - Preempt tracer now shows functions where preemption is disabled but interrupts are still enabled. Other notes: - Updates were done to function tracing to allow better performance with perf. - Infrastructure code has been added to allow for a new histogram feature for recording live trace event histograms that can be configured by simple user commands. The feature itself was just finished, but needs a round in linux-next before being pulled. This only includes some infrastructure changes that will be needed" * tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits) tracing: Record and show NMI state tracing: Fix trace_printk() to print when not using bprintk() tracing: Remove redundant reset per-CPU buff in irqsoff tracer x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c tracing: Fix crash from reading trace_pipe with sendfile tracing: Have preempt(irqs)off trace preempt disabled functions tracing: Fix return while holding a lock in register_tracer() ftrace: Use kasprintf() in ftrace_profile_tracefs() ftrace: Update dynamic ftrace calls only if necessary ftrace: Make ftrace_hash_rec_enable return update bool tracing: Fix typoes in code comment and printk in trace_nop.c tracing, writeback: Replace cgroup path to cgroup ino tracing: Use flags instead of bool in trigger structure tracing: Add an unreg_all() callback to trigger commands tracing: Add needs_rec flag to event triggers tracing: Add a per-event-trigger 'paused' field tracing: Add get_syscall_name() tracing: Add event record param to trigger_ops.func() tracing: Make event trigger functions available tracing: Make ftrace_event_field checking functions available ...
2016-03-22panic: change nmi_panic from macro to functionHidehiro Kawai
Commit 1717f2096b54 ("panic, x86: Fix re-entrance problem due to panic on NMI") and commit 58c5661f2144 ("panic, x86: Allow CPUs to save registers even if looping in NMI context") introduced nmi_panic() which prevents concurrent/recursive execution of panic(). It also saves registers for the crash dump on x86. However, there are some cases where NMI handlers still use panic(). This patch set partially replaces them with nmi_panic() in those cases. Even this patchset is applied, some NMI or similar handlers (e.g. MCE handler) continue to use panic(). This is because I can't test them well and actual problems won't happen. For example, the possibility that normal panic and panic on MCE happen simultaneously is very low. This patch (of 3): Convert nmi_panic() to a proper function and export it instead of exporting internal implementation details to modules, for obvious reasons. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22tracing: Fix trace_printk() to print when not using bprintk()Steven Rostedt (Red Hat)
The trace_printk() code will allocate extra buffers if the compile detects that a trace_printk() is used. To do this, the format of the trace_printk() is saved to the __trace_printk_fmt section, and if that section is bigger than zero, the buffers are allocated (along with a message that this has happened). If trace_printk() uses a format that is not a constant, and thus something not guaranteed to be around when the print happens, the compiler optimizes the fmt out, as it is not used, and the __trace_printk_fmt section is not filled. This means the kernel will not allocate the special buffers needed for the trace_printk() and the trace_printk() will not write anything to the tracing buffer. Adding a "__used" to the variable in the __trace_printk_fmt section will keep it around, even though it is set to NULL. This will keep the string from being printed in the debugfs/tracing/printk_formats section as it is not needed. Reported-by: Vlastimil Babka <vbabka@suse.cz> Fixes: 07d777fe8c398 "tracing: Add percpu buffers for trace_printk()" Cc: stable@vger.kernel.org # v3.5+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: "Highlights: 1) Support more Realtek wireless chips, from Jes Sorenson. 2) New BPF types for per-cpu hash and arrap maps, from Alexei Starovoitov. 3) Make several TCP sysctls per-namespace, from Nikolay Borisov. 4) Allow the use of SO_REUSEPORT in order to do per-thread processing of incoming TCP/UDP connections. The muxing can be done using a BPF program which hashes the incoming packet. From Craig Gallek. 5) Add a multiplexer for TCP streams, to provide a messaged based interface. BPF programs can be used to determine the message boundaries. From Tom Herbert. 6) Add 802.1AE MACSEC support, from Sabrina Dubroca. 7) Avoid factorial complexity when taking down an inetdev interface with lots of configured addresses. We were doing things like traversing the entire address less for each address removed, and flushing the entire netfilter conntrack table for every address as well. 8) Add and use SKB bulk free infrastructure, from Jesper Brouer. 9) Allow offloading u32 classifiers to hardware, and implement for ixgbe, from John Fastabend. 10) Allow configuring IRQ coalescing parameters on a per-queue basis, from Kan Liang. 11) Extend ethtool so that larger link mode masks can be supported. From David Decotigny. 12) Introduce devlink, which can be used to configure port link types (ethernet vs Infiniband, etc.), port splitting, and switch device level attributes as a whole. From Jiri Pirko. 13) Hardware offload support for flower classifiers, from Amir Vadai. 14) Add "Local Checksum Offload". Basically, for a tunneled packet the checksum of the outer header is 'constant' (because with the checksum field filled into the inner protocol header, the payload of the outer frame checksums to 'zero'), and we can take advantage of that in various ways. From Edward Cree" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits) bonding: fix bond_get_stats() net: bcmgenet: fix dma api length mismatch net/mlx4_core: Fix backward compatibility on VFs phy: mdio-thunder: Fix some Kconfig typos lan78xx: add ndo_get_stats64 lan78xx: handle statistics counter rollover RDS: TCP: Remove unused constant RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket net: smc911x: convert pxa dma to dmaengine team: remove duplicate set of flag IFF_MULTICAST bonding: remove duplicate set of flag IFF_MULTICAST net: fix a comment typo ethernet: micrel: fix some error codes ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it bpf, dst: add and use dst_tclassid helper bpf: make skb->tc_classid also readable net: mvneta: bm: clarify dependencies cls_bpf: reset class and reuse major in da ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c ldmvsw: Add ldmvsw.c driver code ...
2016-03-17lib: move strtobool() to kstrtobool()Kees Cook
Create the kstrtobool_from_user() helper and move strtobool() logic into the new kstrtobool() (matching all the other kstrto* functions). Provides an inline wrapper for existing strtobool() callers. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Joe Perches <joe@perches.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Amitkumar Karwar <akarwar@marvell.com> Cc: Nishant Sarmukadam <nishants@marvell.com> Cc: Kalle Valo <kvalo@codeaurora.org> Cc: Steve French <sfrench@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-04uapi: define DIV_ROUND_UP for userlandNicolas Dichtel
DIV_ROUND_UP is defined in linux/kernel.h only for the kernel. When ethtool.h is included by a userland app, we got the following error: include/linux/ethtool.h:1218:8: error: variably modified 'queue_mask' at file scope __u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)]; ^ Let's add a common definition in uapi and use it everywhere. Fixes: ac2c7ad0e5d6 ("net/ethtool: introduce a new ioctl for per queue setting") CC: Kan Liang <kan.liang@intel.com> Suggested-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-16include/linux/kernel.h: change abs() macro so it uses consistent return typeMichal Nazarewicz
Rewrite abs() so that its return type does not depend on the architecture and no unexpected type conversion happen inside of it. The only conversion is from unsigned to signed type. char is left as a return type but treated as a signed type regradless of it's actual signedness. With the old version, int arguments were promoted to long and depending on architecture a long argument might result in s64 or long return type (which may or may not be the same). This came after some back and forth with Nicolas. The current macro has different return type (for the same input type) depending on architecture which might be midly iritating. An alternative version would promote to int like so: #define abs(x) __abs_choose_expr(x, long long, \ __abs_choose_expr(x, long, \ __builtin_choose_expr( \ sizeof(x) <= sizeof(int), \ ({ int __x = (x); __x<0?-__x:__x; }), \ ((void)0)))) I have no preference but imagine Linus might. :] Nicolas argument against is that promoting to int causes iconsistent behaviour: int main(void) { unsigned short a = 0, b = 1, c = a - b; unsigned short d = abs(a - b); unsigned short e = abs(c); printf("%u %u\n", d, e); // prints: 1 65535 } Then again, no sane person expects consistent behaviour from C integer arithmetic. ;) Note: __builtin_types_compatible_p(unsigned char, char) is always false, and __builtin_types_compatible_p(signed char, char) is also always false. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-19panic, x86: Allow CPUs to save registers even if looping in NMI contextHidehiro Kawai
Currently, kdump_nmi_shootdown_cpus(), a subroutine of crash_kexec(), sends an NMI IPI to CPUs which haven't called panic() to stop them, save their register information and do some cleanups for crash dumping. However, if such a CPU is infinitely looping in NMI context, we fail to save its register information into the crash dump. For example, this can happen when unknown NMIs are broadcast to all CPUs as follows: CPU 0 CPU 1 =========================== ========================== receive an unknown NMI unknown_nmi_error() panic() receive an unknown NMI spin_trylock(&panic_lock) unknown_nmi_error() crash_kexec() panic() spin_trylock(&panic_lock) panic_smp_self_stop() infinite loop kdump_nmi_shootdown_cpus() issue NMI IPI -----------> blocked until IRET infinite loop... Here, since CPU 1 is in NMI context, the second NMI from CPU 0 is blocked until CPU 1 executes IRET. However, CPU 1 never executes IRET, so the NMI is not handled and the callback function to save registers is never called. In practice, this can happen on some servers which broadcast NMIs to all CPUs when the NMI button is pushed. To save registers in this case, we need to: a) Return from NMI handler instead of looping infinitely or b) Call the callback function directly from the infinite loop Inherently, a) is risky because NMI is also used to prevent corrupted data from being propagated to devices. So, we chose b). This patch does the following: 1. Move the infinite looping of CPUs which haven't called panic() in NMI context (actually done by panic_smp_self_stop()) outside of panic() to enable us to refer pt_regs. Please note that panic_smp_self_stop() is still used for normal context. 2. Call a callback of kdump_nmi_shootdown_cpus() directly to save registers and do some cleanups after setting waiting_for_crash_ipi which is used for counting down the number of CPUs which handled the callback Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: lkml <linux-kernel@vger.kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Seth Jennings <sjenning@redhat.com> Cc: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Link: http://lkml.kernel.org/r/20151210014628.25437.75256.stgit@softrs [ Cleanup comments, fixup formatting. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19panic, x86: Fix re-entrance problem due to panic on NMIHidehiro Kawai
If panic on NMI happens just after panic() on the same CPU, panic() is recursively called. Kernel stalls, as a result, after failing to acquire panic_lock. To avoid this problem, don't call panic() in NMI context if we've already entered panic(). For that, introduce nmi_panic() macro to reduce code duplication. In the case of panic on NMI, don't return from NMI handlers if another CPU already panicked. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: lkml <linux-kernel@vger.kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seth Jennings <sjenning@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/20151210014626.25437.13302.stgit@softrs [ Cleanup comments, fixup formatting. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-11-09remove abs64()Andrew Morton
Switch everything to the new and more capable implementation of abs(). Mainly to give the new abs() a bit of a workout. Cc: Michal Nazarewicz <mina86@mina86.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-09kernel.h: make abs() work with 64-bit typesMichal Nazarewicz
For 64-bit arguments, the abs macro casts it to an int which leads to lost precision and may cause incorrect results. To deal with 64-bit types abs64 macro has been introduced but still there are places where abs macro is used incorrectly. To deal with the problem, expand abs macro such that it operates on s64 type when dealing with 64-bit types while still returning long when dealing with smaller types. This fixes one known bug (per John): The internal clocksteering done for fine-grained error correction uses a : logarithmic approximation, so any time adjtimex() adjusts the clock : steering, timekeeping_freqadjust() quickly approximates the correct clock : frequency over a series of ticks. : : Unfortunately, the logic in timekeeping_freqadjust(), introduced in commit : dc491596f639438 (Rework frequency adjustments to work better w/ nohz), : used the abs() function with a s64 error value to calculate the size of : the approximated adjustment to be made. : : Per include/linux/kernel.h: "abs() should not be used for 64-bit types : (s64, u64, long long) - use abs64()". : : Thus on 32-bit platforms, this resulted in the clocksteering to take a : quite dampended random walk trying to converge on the proper frequency, : which caused the adjustments to be made much slower then intended (most : easily observed when large adjustments are made). Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Reported-by: John Stultz <john.stultz@linaro.org> Tested-by: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06lib/kasprintf.c: introduce kvasprintf_constRasmus Villemoes
This adds kvasprintf_const which tries to use kstrdup_const if possible: If the format string contains no % characters, or if the format string is exactly "%s", we delegate to kstrdup_const. Otherwise, we fall back to kvasprintf. Just as for kstrdup_const, the main motivation is to save memory by reusing .rodata when possible. The return value should be freed by kfree_const, just like for kstrdup_const. There is deliberately no kasprintf_const: In the vast majority of cases, the format string argument is a literal, so one can determine statically whether one could instead use kstrdup_const directly (which would also require one to change all corresponding kfree calls to kfree_const). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17include, lib: add __printf attributes to several function prototypesNicolas Iooss
Using __printf attributes helps to detect several format string issues at compile time (even though -Wformat-security is currently disabled in Makefile). For example it can detect when formatting a pointer as a number, like the issue fixed in commit a3fa71c40f18 ("wl18xx: show rx_frames_per_rates as an array as it really is"), or when the arguments do not match the format string, c.f. for example commit 5ce1aca81435 ("reiserfs: fix __RASSERT format string"). To prevent similar bugs in the future, add a __printf attribute to every function prototype which needs one in include/linux/ and lib/. These functions were mostly found by using gcc's -Wsuggest-attribute=format flag. Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Felipe Balbi <balbi@ti.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-01Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge third patchbomb from Andrew Morton: - the rest of MM - scripts/gdb updates - ipc/ updates - lib/ updates - MAINTAINERS updates - various other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (67 commits) genalloc: rename of_get_named_gen_pool() to of_gen_pool_get() genalloc: rename dev_get_gen_pool() to gen_pool_get() x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit MAINTAINERS: add zpool MAINTAINERS: BCACHE: Kent Overstreet has changed email address MAINTAINERS: move Jens Osterkamp to CREDITS MAINTAINERS: remove unused nbd.h pattern MAINTAINERS: update brcm gpio filename pattern MAINTAINERS: update brcm dts pattern MAINTAINERS: update sound soc intel patterns MAINTAINERS: remove website for paride MAINTAINERS: update Emulex ocrdma email addresses bcache: use kvfree() in various places libcxgbi: use kvfree() in cxgbi_free_big_mem() target: use kvfree() in session alloc and free IB/ehca: use kvfree() in ipz_queue_{cd}tor() drm/nouveau/gem: use kvfree() in u_free() drm: use kvfree() in drm_free_large() cxgb4: use kvfree() in t4_free_mem() cxgb3: use kvfree() in cxgb_free_mem() ...
2015-07-01Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Main excitement here is Peter Zijlstra's lockless rbtree optimization to speed module address lookup. He found some abusers of the module lock doing that too. A little bit of parameter work here too; including Dan Streetman's breaking up the big param mutex so writing a parameter can load another module (yeah, really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were appended too" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits) modules: only use mod->param_lock if CONFIG_MODULES param: fix module param locks when !CONFIG_SYSFS. rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() module: add per-module param_lock module: make perm const params: suppress unused variable error, warn once just in case code changes. modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'. kernel/module.c: avoid ifdefs for sig_enforce declaration kernel/workqueue.c: remove ifdefs over wq_power_efficient kernel/params.c: export param_ops_bool_enable_only kernel/params.c: generalize bool_enable_only kernel/module.c: use generic module param operaters for sig_enforce kernel/params: constify struct kernel_param_ops uses sysfs: tightened sysfs permission checks module: Rework module_addr_{min,max} module: Use __module_address() for module_address_lookup() module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING module: Optimize __module_address() using a latched RB-tree rbtree: Implement generic latch_tree seqlock: Introduce raw_read_seqcount_latch() ...
2015-06-30kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops pathHATAYAMA Daisuke
Commit f06e5153f4ae2e ("kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump after panic_notifers") introduced "crash_kexec_post_notifiers" kernel boot option, which toggles wheather panic() calls crash_kexec() before panic_notifiers and dump kmsg or after. The problem is that the commit overlooks panic_on_oops kernel boot option. If it is enabled, crash_kexec() is called directly without going through panic() in oops path. To fix this issue, this patch adds a check to "crash_kexec_post_notifiers" in the condition of kexec_should_crash(). Also, put a comment in kexec_should_crash() to explain not obvious things on this patch. Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Acked-by: Baoquan He <bhe@redhat.com> Tested-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-26Merge tag 'trace-v4.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "This patch series contains several clean ups and even a new trace clock "monitonic raw". Also some enhancements to make the ring buffer even faster. But the biggest and most noticeable change is the renaming of the ftrace* files, structures and variables that have to deal with trace events. Over the years I've had several developers tell me about their confusion with what ftrace is compared to events. Technically, "ftrace" is the infrastructure to do the function hooks, which include tracing and also helps with live kernel patching. But the trace events are a separate entity altogether, and the files that affect the trace events should not be named "ftrace". These include: include/trace/ftrace.h -> include/trace/trace_events.h include/linux/ftrace_event.h -> include/linux/trace_events.h Also, functions that are specific for trace events have also been renamed: ftrace_print_*() -> trace_print_*() (un)register_ftrace_event() -> (un)register_trace_event() ftrace_event_name() -> trace_event_name() ftrace_trigger_soft_disabled() -> trace_trigger_soft_disabled() ftrace_define_fields_##call() -> trace_define_fields_##call() ftrace_get_offsets_##call() -> trace_get_offsets_##call() Structures have been renamed: ftrace_event_file -> trace_event_file ftrace_event_{call,class} -> trace_event_{call,class} ftrace_event_buffer -> trace_event_buffer ftrace_subsystem_dir -> trace_subsystem_dir ftrace_event_raw_##call -> trace_event_raw_##call ftrace_event_data_offset_##call-> trace_event_data_offset_##call ftrace_event_type_funcs_##call -> trace_event_type_funcs_##call And a few various variables and flags have also been updated. This has been sitting in linux-next for some time, and I have not heard a single complaint about this rename breaking anything. Mostly because these functions, variables and structures are mostly internal to the tracing system and are seldom (if ever) used by anything external to that" * tag 'trace-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) ring_buffer: Allow to exit the ring buffer benchmark immediately ring-buffer-benchmark: Fix the wrong type ring-buffer-benchmark: Fix the wrong param in module_param ring-buffer: Add enum names for the context levels ring-buffer: Remove useless unused tracing_off_permanent() ring-buffer: Give NMIs a chance to lock the reader_lock ring-buffer: Add trace_recursive checks to ring_buffer_write() ring-buffer: Allways do the trace_recursive checks ring-buffer: Move recursive check to per_cpu descriptor ring-buffer: Add unlikelys to make fast path the default tracing: Rename ftrace_get_offsets_##call() to trace_event_get_offsets_##call() tracing: Rename ftrace_define_fields_##call() to trace_event_define_fields_##call() tracing: Rename ftrace_event_type_funcs_##call to trace_event_type_funcs_##call tracing: Rename ftrace_data_offset_##call to trace_event_data_offset_##call tracing: Rename ftrace_raw_##call event structures to trace_event_raw_##call tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled() tracing: Rename FTRACE_EVENT_FL_* flags to EVENT_FILE_FL_* tracing: Rename struct ftrace_subsystem_dir to trace_subsystem_dir tracing: Rename ftrace_event_name() to trace_event_name() tracing: Rename FTRACE_MAX_EVENT to TRACE_EVENT_TYPE_MAX ...
2015-05-28ring-buffer: Remove useless unused tracing_off_permanent()Steven Rostedt (Red Hat)
The tracing_off_permanent() call is a way to disable all ring_buffers. Nothing uses it and nothing should use it, as tracing_off() and friends are better, as they disable the ring buffers related to tracing. The tracing_off_permanent() even disabled non tracing ring buffers. This is a bit drastic, and was added to handle NMIs doing outputs that could corrupt the ring buffer when only tracing used them. It is now obsolete and adds a little overhead, it should be removed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-05-28sysfs: tightened sysfs permission checksGobinda Charan Maji
There were some inconsistency in restriction to VERIFY_OCTAL_PERMISSIONS(). Previously the test was "User perms >= group perms >= other perms". The permission field of User, Group or Other consists of three bits. LSB is EXECUTE permission, MSB is READ permission and the middle bit is WRITE permission. But logically WRITE is "more privileged" than READ. Say for example, permission value is "0430". Here User has only READ permission whereas Group has both WRITE and EXECUTE permission. So, the checks could be tightened and the tests are separated to USER_READABLE >= GROUP_READABLE >= OTHER_READABLE, USER_WRITABLE >= GROUP_WRITABLE and OTHER_WRITABLE is not permitted. Signed-off-by: Gobinda Charan Maji <gobinda.cemk07@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-19sched/preempt, mm/fault: Trigger might_sleep() in might_fault() with ↵David Hildenbrand
disabled pagefaults Commit 662bbcb2747c ("mm, sched: Allow uaccess in atomic with pagefault_disable()") removed might_sleep() checks for all user access code (that uses might_fault()). The reason was to disable wrong "sleep in atomic" warnings in the following scenario: pagefault_disable() rc = copy_to_user(...) pagefault_enable() Which is valid, as pagefault_disable() increments the preempt counter and therefore disables the pagefault handler. copy_to_user() will not sleep and return an error code if a page is not available. However, as all might_sleep() checks are removed, CONFIG_DEBUG_ATOMIC_SLEEP would no longer detect the following scenario: spin_lock(&lock); rc = copy_to_user(...) spin_unlock(&lock) If the kernel is compiled with preemption turned on, preempt_disable() will make in_atomic() detect disabled preemption. The fault handler would correctly never sleep on user access. However, with preemption turned off, preempt_disable() is usually a NOP (with !CONFIG_PREEMPT_COUNT), therefore in_atomic() will not be able to detect disabled preemption nor disabled pagefaults. The fault handler could sleep. We really want to enable CONFIG_DEBUG_ATOMIC_SLEEP checks for user access functions again, otherwise we can end up with horrible deadlocks. Root of all evil is that pagefault_disable() acts almost as preempt_disable(), depending on preemption being turned on/off. As we now have pagefault_disabled(), we can use it to distinguish whether user acces functions might sleep. Convert might_fault() into a makro that calls __might_fault(), to allow proper file + line messages in case of a might_sleep() warning. Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: airlied@linux.ie Cc: akpm@linux-foundation.org Cc: benh@kernel.crashing.org Cc: bigeasy@linutronix.de Cc: borntraeger@de.ibm.com Cc: daniel.vetter@intel.com Cc: heiko.carstens@de.ibm.com Cc: herbert@gondor.apana.org.au Cc: hocko@suse.cz Cc: hughd@google.com Cc: mst@redhat.com Cc: paulus@samba.org Cc: ralf@linux-mips.org Cc: schwidefsky@de.ibm.com Cc: yang.shi@windriver.com Link: http://lkml.kernel.org/r/1431359540-32227-3-git-send-email-dahi@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17kernel.h: implement DIV_ROUND_CLOSEST_ULLJavi Merino
We have grown a number of different implementations of DIV_ROUND_CLOSEST_ULL throughout the kernel. Move the i915 one to kernel.h so that it can be reused. Signed-off-by: Javi Merino <javi.merino@arm.com> Reviewed-by: Jeff Epler <jepler@unpythonic.net> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Guenter Roeck <linux@roeck-us.net> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Alex Elder <elder@linaro.org> Cc: Antti Palosaari <crope@iki.fi> Cc: Javi Merino <javi.merino@arm.com> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12kernel.h: remove ancient __FUNCTION__ hackRasmus Villemoes
__FUNCTION__ hasn't been treated as a string literal since gcc 3.4, so this only helps people who only test-compile using 3.3 (compiler-gcc3.h barks at anything older than that). Besides, there are almost no occurrences of __FUNCTION__ left in the tree. [akpm@linux-foundation.org: convert remaining __FUNCTION__ references] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull live patching infrastructure from Jiri Kosina: "Let me provide a bit of history first, before describing what is in this pile. Originally, there was kSplice as a standalone project that implemented stop_machine()-based patching for the linux kernel. This project got later acquired, and the current owner is providing live patching as a proprietary service, without any intentions to have their implementation merged. Then, due to rising user/customer demand, both Red Hat and SUSE started working on their own implementation (not knowing about each other), and announced first versions roughly at the same time [1] [2]. The principle difference between the two solutions is how they are making sure that the patching is performed in a consistent way when it comes to different execution threads with respect to the semantic nature of the change that is being introduced. In a nutshell, kPatch is issuing stop_machine(), then looking at stacks of all existing processess, and if it decides that the system is in a state that can be patched safely, it proceeds insterting code redirection machinery to the patched functions. On the other hand, kGraft provides a per-thread consistency during one single pass of a process through the kernel and performs a lazy contignuous migration of threads from "unpatched" universe to the "patched" one at safe checkpoints. If interested in a more detailed discussion about the consistency models and its possible combinations, please see the thread that evolved around [3]. It pretty quickly became obvious to the interested parties that it's absolutely impractical in this case to have several isolated solutions for one task to co-exist in the kernel. During a dedicated Live Kernel Patching track at LPC in Dusseldorf, all the interested parties sat together and came up with a joint aproach that would work for both distro vendors. Steven Rostedt took notes [4] from this meeting. And the foundation for that aproach is what's present in this pull request. It provides a basic infrastructure for function "live patching" (i.e. code redirection), including API for kernel modules containing the actual patches, and API/ABI for userspace to be able to operate on the patches (look up what patches are applied, enable/disable them, etc). It's relatively simple and minimalistic, as it's making use of existing kernel infrastructure (namely ftrace) as much as possible. It's also self-contained, in a sense that it doesn't hook itself in any other kernel subsystem (it doesn't even touch any other code). It's now implemented for x86 only as a reference architecture, but support for powerpc, s390 and arm is already in the works (adding arch-specific support basically boils down to teaching ftrace about regs-saving). Once this common infrastructure gets merged, both Red Hat and SUSE have agreed to immediately start porting their current solutions on top of this, abandoning their out-of-tree code. The plan basically is that each patch will be marked by flag(s) that would indicate which consistency model it is willing to use (again, the details have been sketched out already in the thread at [3]). Before this happens, the current codebase can be used to patch a large group of secruity/stability problems the patches for which are not too complex (in a sense that they don't introduce non-trivial change of function's return value semantics, they don't change layout of data structures, etc) -- this corresponds to LEAVE_FUNCTION && SWITCH_FUNCTION semantics described at [3]. This tree has been in linux-next since December. [1] https://lkml.org/lkml/2014/4/30/477 [2] https://lkml.org/lkml/2014/7/14/857 [3] https://lkml.org/lkml/2014/11/7/354 [4] http://linuxplumbersconf.org/2014/wp-content/uploads/2014/10/LPC2014_LivePatching.txt [ The core code is introduced by the three commits authored by Seth Jennings, which got a lot of changes incorporated during numerous respins and reviews of the initial implementation. All the followup commits have materialized only after public tree has been created, so they were not folded into initial three commits so that the public tree doesn't get rebased ]" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: add missing newline to error message livepatch: rename config to CONFIG_LIVEPATCH livepatch: fix uninitialized return value livepatch: support for repatching a function livepatch: enforce patch stacking semantics livepatch: change ARCH_HAVE_LIVE_PATCHING to HAVE_LIVE_PATCHING livepatch: fix deferred module patching order livepatch: handle ancient compilers with more grace livepatch: kconfig: use bool instead of boolean livepatch: samples: fix usage example comments livepatch: MAINTAINERS: add git tree location livepatch: use FTRACE_OPS_FL_IPMODIFY livepatch: move x86 specific ftrace handler code to arch/x86 livepatch: samples: add sample live patching module livepatch: kernel: add support for live patching livepatch: kernel: add TAINT_LIVEPATCH
2015-02-01sched: don't cause task state changes in nested sleep debuggingLinus Torvalds
Commit 8eb23b9f35aa ("sched: Debug nested sleeps") added code to report on nested sleep conditions, which we generally want to avoid because the inner sleeping operation can re-set the thread state to TASK_RUNNING, but that will then cause the outer sleep loop not actually sleep when it calls schedule. However, that's actually valid traditional behavior, with the inner sleep being some fairly rare case (like taking a sleeping lock that normally doesn't actually need to sleep). And the debug code would actually change the state of the task to TASK_RUNNING internally, which makes that kind of traditional and working code not work at all, because now the nested sleep doesn't just sometimes cause the outer one to not block, but will cause it to happen every time. In particular, it will cause the cardbus kernel daemon (pccardd) to basically busy-loop doing scheduling, converting a laptop into a heater, as reported by Bruno Prémont. But there may be other legacy uses of that nested sleep model in other drivers that are also likely to never get converted to the new model. This fixes both cases: - don't set TASK_RUNNING when the nested condition happens (note: even if WARN_ONCE() only _warns_ once, the return value isn't whether the warning happened, but whether the condition for the warning was true. So despite the warning only happening once, the "if (WARN_ON(..))" would trigger for every nested sleep. - in the cases where we knowingly disable the warning by using "sched_annotate_sleep()", don't change the task state (that is used for all core scheduling decisions), instead use '->task_state_change' that is used for the debugging decision itself. (Credit for the second part of the fix goes to Oleg Nesterov: "Can't we avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the suggested change to use 'task_state_change' as part of the test) Reported-and-bisected-by: Bruno Prémont <bonbons@linux-vserver.org> Tested-by: Rafael J Wysocki <rjw@rjwysocki.net> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de>, Cc: Ilya Dryomov <ilya.dryomov@inktank.com>, Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Hurley <peter@hurleysoftware.com>, Cc: Davidlohr Bueso <dave@stgolabs.net>, Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-22livepatch: kernel: add TAINT_LIVEPATCHSeth Jennings
This adds a new taint flag to indicate when the kernel or a kernel module has been live patched. This will provide a clean indication in bug reports that live patching was used. Additionally, if the crash occurs in a live patched function, the live patch module will appear beside the patched function in the backtrace. Signed-off-by: Seth Jennings <sjenning@redhat.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-12-14Merge tag 'tty-3.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Here's the big tty/serial driver update for 3.19-rc1. There are a number of TTY core changes/fixes in here from Peter Hurley that have all been teted in linux-next for a long time now. There are also the normal serial driver updates as well, full details in the changelog below" * tag 'tty-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (219 commits) serial: pxa: hold port.lock when reporting modem line changes tty-hvsi_lib: Deletion of an unnecessary check before the function call "tty_kref_put" tty: Deletion of unnecessary checks before two function calls n_tty: Fix read_buf race condition, increment read_head after pushing data serial: of-serial: add PM suspend/resume support Revert "serial: of-serial: add PM suspend/resume support" Revert "serial: of-serial: fix up PM ops on no_console_suspend and port type" serial: 8250: don't attempt a trylock if in sysrq serial: core: Add big-endian iotype serial: samsung: use port->fifosize instead of hardcoded values serial: samsung: prefer to use fifosize from driver data serial: samsung: fix style problems serial: samsung: wait for transfer completion before clock disable serial: icom: fix error return code serial: tegra: clean up tty-flag assignments serial: Fix io address assign flow with Fintek PCI-to-UART Product serial: mxs-auart: fix tx_empty against shift register serial: mxs-auart: fix gpio change detection on interrupt serial: mxs-auart: Fix mxs_auart_set_ldisc() serial: 8250_dw: Use 64-bit access for OCTEON. ...
2014-12-10kernel: add panic_on_warnPrarit Bhargava
There have been several times where I have had to rebuild a kernel to cause a panic when hitting a WARN() in the code in order to get a crash dump from a system. Sometimes this is easy to do, other times (such as in the case of a remote admin) it is not trivial to send new images to the user. A much easier method would be a switch to change the WARN() over to a panic. This makes debugging easier in that I can now test the actual image the WARN() was seen on and I do not have to engage in remote debugging. This patch adds a panic_on_warn kernel parameter and /proc/sys/kernel/panic_on_warn calls panic() in the warn_slowpath_common() path. The function will still print out the location of the warning. An example of the panic_on_warn output: The first line below is from the WARN_ON() to output the WARN_ON()'s location. After that the panic() output is displayed. WARNING: CPU: 30 PID: 11698 at /home/prarit/dummy_module/dummy-module.c:25 init_dummy+0x1f/0x30 [dummy_module]() Kernel panic - not syncing: panic_on_warn set ... CPU: 30 PID: 11698 Comm: insmod Tainted: G W OE 3.17.0+ #57 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013 0000000000000000 000000008e3f87df ffff88080f093c38 ffffffff81665190 0000000000000000 ffffffff818aea3d ffff88080f093cb8 ffffffff8165e2ec ffffffff00000008 ffff88080f093cc8 ffff88080f093c68 000000008e3f87df Call Trace: [<ffffffff81665190>] dump_stack+0x46/0x58 [<ffffffff8165e2ec>] panic+0xd0/0x204 [<ffffffffa038e05f>] ? init_dummy+0x1f/0x30 [dummy_module] [<ffffffff81076b90>] warn_slowpath_common+0xd0/0xd0 [<ffffffffa038e040>] ? dummy_greetings+0x40/0x40 [dummy_module] [<ffffffff81076c8a>] warn_slowpath_null+0x1a/0x20 [<ffffffffa038e05f>] init_dummy+0x1f/0x30 [dummy_module] [<ffffffff81002144>] do_one_initcall+0xd4/0x210 [<ffffffff811b52c2>] ? __vunmap+0xc2/0x110 [<ffffffff810f8889>] load_module+0x16a9/0x1b30 [<ffffffff810f3d30>] ? store_uevent+0x70/0x70 [<ffffffff810f49b9>] ? copy_module_from_fd.isra.44+0x129/0x180 [<ffffffff810f8ec6>] SyS_finit_module+0xa6/0xd0 [<ffffffff8166cf29>] system_call_fastpath+0x12/0x17 Successfully tested by me. hpa said: There is another very valid use for this: many operators would rather a machine shuts down than being potentially compromised either functionally or security-wise. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-05tty: Move session_of_pgrp() and make staticPeter Hurley
tiocspgrp() is the lone caller of session_of_pgrp(); relocate and limit to file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-28sched: Exclude cond_resched() from nested sleep testPeter Zijlstra
cond_resched() is a preemption point, not strictly a blocking primitive, so exclude it from the ->state test. In particular, preemption preserves task_struct::state. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: tglx@linutronix.de Cc: ilya.dryomov@inktank.com Cc: umgwanakikbuti@gmail.com Cc: oleg@redhat.com Cc: Alex Elder <alex.elder@linaro.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Axel Lin <axel.lin@ingics.com> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Dave Jones <davej@redhat.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20140924082242.656559952@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28sched, exit: Deal with nested sleepsPeter Zijlstra
do_wait() is a big wait loop, but we set TASK_RUNNING too late; we end up calling potential sleeps before we reset it. Not strictly a bug since we're guaranteed to exit the loop and not call schedule(); put in annotations to quiet might_sleep(). WARNING: CPU: 0 PID: 1 at ../kernel/sched/core.c:7123 __might_sleep+0x7e/0x90() do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8109a788>] do_wait+0x88/0x270 Call Trace: [<ffffffff81694991>] dump_stack+0x4e/0x7a [<ffffffff8109877c>] warn_slowpath_common+0x8c/0xc0 [<ffffffff8109886c>] warn_slowpath_fmt+0x4c/0x50 [<ffffffff810bca6e>] __might_sleep+0x7e/0x90 [<ffffffff811a1c15>] might_fault+0x55/0xb0 [<ffffffff8109a3fb>] wait_consider_task+0x90b/0xc10 [<ffffffff8109a804>] do_wait+0x104/0x270 [<ffffffff8109b837>] SyS_wait4+0x77/0x100 [<ffffffff8169d692>] system_call_fastpath+0x16/0x1b Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: tglx@linutronix.de Cc: umgwanakikbuti@gmail.com Cc: ilya.dryomov@inktank.com Cc: Alex Elder <alex.elder@linaro.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Axel Lin <axel.lin@ingics.com> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Dave Jones <davej@redhat.com> Cc: Guillaume Morin <guillaume@morinfr.org> Cc: Ionut Alexa <ionut.m.alexa@gmail.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Michal Schmidt <mschmidt@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20140924082242.186408915@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-23Merge branch 'x86-efi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 EFI updates from Peter Anvin: "This patchset falls under the "maintainers that grovel" clause in the v3.18-rc1 announcement. We had intended to push it late in the merge window since we got it into the -tip tree relatively late. Many of these are relatively simple things, but there are a couple of key bits, especially Ard's and Matt's patches" * 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) rtc: Disable EFI rtc for x86 efi: rtc-efi: Export platform:rtc-efi as module alias efi: Delete the in_nmi() conditional runtime locking efi: Provide a non-blocking SetVariable() operation x86/efi: Adding efi_printks on memory allocationa and pci.reads x86/efi: Mark initialization code as such x86/efi: Update comment regarding required phys mapped EFI services x86/efi: Unexport add_efi_memmap variable x86/efi: Remove unused efi_call* macros efi: Resolve some shadow warnings arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format() ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format() x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format() efi: Introduce efi_md_typeattr_format() efi: Add macro for EFI_MEMORY_UCE memory attribute x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi arm64/efi: uefi_init error handling fix efi: Add kernel param efi=noruntime lib: Add a generic cmdline parse function parse_option_str ...
2014-10-14include/linux: remove strict_strto* definitionsDaniel Walter
Remove obsolete and unused strict_strto* functions Signed-off-by: Daniel Walter <dwalter@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-12Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris. Mostly ima, selinux, smack and key handling updates. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits) integrity: do zero padding of the key id KEYS: output last portion of fingerprint in /proc/keys KEYS: strip 'id:' from ca_keyid KEYS: use swapped SKID for performing partial matching KEYS: Restore partial ID matching functionality for asymmetric keys X.509: If available, use the raw subjKeyId to form the key description KEYS: handle error code encoded in pointer selinux: normalize audit log formatting selinux: cleanup error reporting in selinux_nlmsg_perm() KEYS: Check hex2bin()'s return when generating an asymmetric key ID ima: detect violations for mmaped files ima: fix race condition on ima_rdwr_violation_check and process_measurement ima: added ima_policy_flag variable ima: return an error code from ima_add_boot_aggregate() ima: provide 'ima_appraise=log' kernel option ima: move keyring initialization to ima_init() PKCS#7: Handle PKCS#7 messages that contain no X.509 certs PKCS#7: Better handling of unsupported crypto KEYS: Overhaul key identification when searching for asymmetric keys KEYS: Implement binary asymmetric key ID handling ...
2014-10-09include/linux/kernel.h: deduplicate code implementing clamp* macrosMichal Nazarewicz
Instead of open-coding clamp_t macro min_t and max_t the way clamp macro does and instead of open-coding clamp_val simply use clamp_t. Furthermore, normalise argument naming in the macros to be lo and hi. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Cc: Mark Rustad <mark.d.rustad@intel.com> Cc: "Kirsher, Jeffrey T" <jeffrey.t.kirsher@intel.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09include/linux/kernel.h: rewrite min3, max3 and clamp using min and maxMichal Nazarewicz
It appears that gcc is better at optimising a double call to min and max rather than open coded min3 and max3. This can be observed here: $ cat min-max.c #define min(x, y) ({ \ typeof(x) _min1 = (x); \ typeof(y) _min2 = (y); \ (void) (&_min1 == &_min2); \ _min1 < _min2 ? _min1 : _min2; }) #define min3(x, y, z) ({ \ typeof(x) _min1 = (x); \ typeof(y) _min2 = (y); \ typeof(z) _min3 = (z); \ (void) (&_min1 == &_min2); \ (void) (&_min1 == &_min3); \ _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \ (_min2 < _min3 ? _min2 : _min3); }) int fmin3(int x, int y, int z) { return min3(x, y, z); } int fmin2(int x, int y, int z) { return min(min(x, y), z); } $ gcc -O2 -o min-max.s -S min-max.c; cat min-max.s .file "min-max.c" .text .p2align 4,,15 .globl fmin3 .type fmin3, @function fmin3: .LFB0: .cfi_startproc cmpl %esi, %edi jl .L5 cmpl %esi, %edx movl %esi, %eax cmovle %edx, %eax ret .p2align 4,,10 .p2align 3 .L5: cmpl %edi, %edx movl %edi, %eax cmovle %edx, %eax ret .cfi_endproc .LFE0: .size fmin3, .-fmin3 .p2align 4,,15 .globl fmin2 .type fmin2, @function fmin2: .LFB1: .cfi_startproc cmpl %edi, %esi movl %edx, %eax cmovle %esi, %edi cmpl %edx, %edi cmovle %edi, %eax ret .cfi_endproc .LFE1: .size fmin2, .-fmin2 .ident "GCC: (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3" .section .note.GNU-stack,"",@progbits fmin3 function, which uses open-coded min3 macro, is compiled into total of ten instructions including a conditional branch, whereas fmin2 function, which uses two calls to min2 macro, is compiled into six instructions with no branches. Similarly, open-coded clamp produces the same code as clamp using min and max macros, but the latter is much shorter: $ cat clamp.c #define clamp(val, min, max) ({ \ typeof(val) __val = (val); \ typeof(min) __min = (min); \ typeof(max) __max = (max); \ (void) (&__val == &__min); \ (void) (&__val == &__max); \ __val = __val < __min ? __min: __val; \ __val > __max ? __max: __val; }) #define min(x, y) ({ \ typeof(x) _min1 = (x); \ typeof(y) _min2 = (y); \ (void) (&_min1 == &_min2); \ _min1 < _min2 ? _min1 : _min2; }) #define max(x, y) ({ \ typeof(x) _max1 = (x); \ typeof(y) _max2 = (y); \ (void) (&_max1 == &_max2); \ _max1 > _max2 ? _max1 : _max2; }) int fclamp(int v, int min, int max) { return clamp(v, min, max); } int fclampmm(int v, int min, int max) { return min(max(v, min), max); } $ gcc -O2 -o clamp.s -S clamp.c; cat clamp.s .file "clamp.c" .text .p2align 4,,15 .globl fclamp .type fclamp, @function fclamp: .LFB0: .cfi_startproc cmpl %edi, %esi movl %edx, %eax cmovge %esi, %edi cmpl %edx, %edi cmovle %edi, %eax ret .cfi_endproc .LFE0: .size fclamp, .-fclamp .p2align 4,,15 .globl fclampmm .type fclampmm, @function fclampmm: .LFB1: .cfi_startproc cmpl %edi, %esi cmovge %esi, %edi cmpl %edi, %edx movl %edi, %eax cmovle %edx, %eax ret .cfi_endproc .LFE1: .size fclampmm, .-fclampmm .ident "GCC: (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3" .section .note.GNU-stack,"",@progbits Linux mpn-glaptop 3.13.0-29-generic #53~precise1-Ubuntu SMP Wed Jun 4 22:06:25 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3 Copyright (C) 2011 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. -rwx------ 1 mpn eng 51224656 Jun 17 14:15 vmlinux.before -rwx------ 1 mpn eng 51224608 Jun 17 13:57 vmlinux.after 48 bytes reduction. The do_fault_around was a few instruction shorter and as far as I can tell saved 12 bytes on the stack, i.e.: $ grep -e rsp -e pop -e push do_fault_around.* do_fault_around.before.s:push %rbp do_fault_around.before.s:mov %rsp,%rbp do_fault_around.before.s:push %r13 do_fault_around.before.s:push %r12 do_fault_around.before.s:push %rbx do_fault_around.before.s:sub $0x38,%rsp do_fault_around.before.s:add $0x38,%rsp do_fault_around.before.s:pop %rbx do_fault_around.before.s:pop %r12 do_fault_around.before.s:pop %r13 do_fault_around.before.s:pop %rbp do_fault_around.after.s:push %rbp do_fault_around.after.s:mov %rsp,%rbp do_fault_around.after.s:push %r12 do_fault_around.after.s:push %rbx do_fault_around.after.s:sub $0x30,%rsp do_fault_around.after.s:add $0x30,%rsp do_fault_around.after.s:pop %rbx do_fault_around.after.s:pop %r12 do_fault_around.after.s:pop %rbp or here side-by-side: Before After push %rbp push %rbp mov %rsp,%rbp mov %rsp,%rbp push %r13 push %r12 push %r12 push %rbx push %rbx sub $0x38,%rsp sub $0x30,%rsp add $0x38,%rsp add $0x30,%rsp pop %rbx pop %rbx pop %r12 pop %r12 pop %r13 pop %rbp pop %rbp There are also fewer branches: $ grep ^j do_fault_around.* do_fault_around.before.s:jae ffffffff812079b7 do_fault_around.before.s:jmp ffffffff812079c5 do_fault_around.before.s:jmp ffffffff81207a14 do_fault_around.before.s:ja ffffffff812079f9 do_fault_around.before.s:jb ffffffff81207a10 do_fault_around.before.s:jmp ffffffff81207a63 do_fault_around.before.s:jne ffffffff812079df do_fault_around.after.s:jmp ffffffff812079fd do_fault_around.after.s:ja ffffffff812079e2 do_fault_around.after.s:jb ffffffff812079f9 do_fault_around.after.s:jmp ffffffff81207a4c do_fault_around.after.s:jne ffffffff812079c8 And here's with allyesconfig on a different machine: $ uname -a; gcc --version; ls -l vmlinux.* Linux erwin 3.14.7-mn #54 SMP Sun Jun 15 11:25:08 CEST 2014 x86_64 AMD Phenom(tm) II X3 710 Processor AuthenticAMD GNU/Linux gcc (GCC) 4.8.3 Copyright (C) 2013 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. -rwx------ 1 mpn eng 437027411 Jun 20 16:04 vmlinux.before -rwx------ 1 mpn eng 437026881 Jun 20 15:30 vmlinux.after 530 bytes reduction. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: David Rientjes <rientjes@google.com> Cc: "Rustad, Mark D" <mark.d.rustad@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-03lib: Add a generic cmdline parse function parse_option_strDave Young
There should be a generic function to parse params like a=b,c Adding parse_option_str in lib/cmdline.c which will return true if there's specified option set in the params. Also updated efi=old_map parsing code to use the new function Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-09-16Provide a binary to hex conversion functionDavid Howells
Provide a function to convert a buffer of binary data into an unterminated ascii hex string representation of that data. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-08-10Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "This finally applies the stricter sysfs perms checking we pulled out before last merge window. A few stragglers are fixed (thanks linux-next!)" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: arch/powerpc/platforms/powernv/opal-dump.c: fix world-writable sysfs files arch/powerpc/platforms/powernv/opal-elog.c: fix world-writable sysfs files drivers/video/fbdev/s3c2410fb.c: don't make debug world-writable. ARM: avoid ARM binutils leaking ELF local symbols scripts: modpost: Remove numeric suffix pattern matching scripts: modpost: fix compilation warning sysfs: disallow world-writable files. module: return bool from within_module*() module: add within_module() function modules: Fix build error in moduleloader.h
2014-08-08panic: add TAINT_SOFTLOCKUPJosh Hunt
This taint flag will be set if the system has ever entered a softlockup state. Similar to TAINT_WARN it is useful to know whether or not the system has been in a softlockup state when debugging. [akpm@linux-foundation.org: apply the taint before calling panic()] Signed-off-by: Josh Hunt <johunt@akamai.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06kernel.h: remove deprecated pack_hex_byteJoe Perches
It's been nearly 3 years now since commit 55036ba76b2d ("lib: rename pack_hex_byte() to hex_byte_pack()") so it's time to remove this deprecated and unused static inline. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-27sysfs: disallow world-writable files.Rusty Russell
This check was introduced in 2006 by Alexey Dobriyan (9774a1f54f173) for module parameters; we removed it when we unified the check into VERIFY_OCTAL_PERMISSIONS() as sysfs didn't have the same requirement. Now all those users are fixed, reintroduce it. Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Dave Jones <davej@redhat.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-06-25mac_pton: Use bool not int returnJoe Perches
Use bool instead of int as the return type. All uses are tested with !. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-06Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Nothing major: the stricter permissions checking for sysfs broke a staging driver; fix included. Greg KH said he'd take the patch but hadn't as the merge window opened, so it's included here to avoid breaking build" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: staging: fix up speakup kobject mode Use 'E' instead of 'X' for unsigned module taint flag. VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms. kallsyms: fix percpu vars on x86-64 with relocation. kallsyms: generalize address range checking module: LLVMLinux: Remove unused function warning from __param_check macro Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE module: remove MODULE_GENERIC_TABLE module: allow multiple calls to MODULE_DEVICE_TABLE() per module module: use pr_cont