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* Merge branch 'next' into upstream for v3.19Paul Moore2014-12-091-1/+1
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| * audit: convert status version to a feature bitmapRichard Guy Briggs2014-11-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The version field defined in the audit status structure was found to have limitations in terms of its expressibility of features supported. This is distict from the get/set features call to be able to command those features that are present. Converting this field from a version number to a feature bitmap will allow distributions to selectively backport and support certain features and will allow upstream to be able to deprecate features in the future. It will allow userspace clients to first query the kernel for which features are actually present and supported. Currently, EINVAL is returned rather than EOPNOTSUP, which isn't helpful in determining if there was an error in the command, or if it simply isn't supported yet. Past features are not represented by this bitmap, but their use may be converted to EOPNOTSUP if needed in the future. Since "version" is too generic to convert with a #define, use a union in the struct status, introducing the member "feature_bitmap" unionized with "version". Convert existing AUDIT_VERSION_* macros over to AUDIT_FEATURE_BITMAP* counterparts, leaving the former for backwards compatibility. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: minor whitespace tweaks] Signed-off-by: Paul Moore <pmoore@redhat.com>
* | audit: keep inode pinnedMiklos Szeredi2014-11-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Audit rules disappear when an inode they watch is evicted from the cache. This is likely not what we want. The guilty commit is "fsnotify: allow marks to not pin inodes in core", which didn't take into account that audit_tree adds watches with a zero mask. Adding any mask should fix this. Fixes: 90b1e7a57880 ("fsnotify: allow marks to not pin inodes in core") Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org # 2.6.36+ Signed-off-by: Paul Moore <pmoore@redhat.com>
* | audit: AUDIT_FEATURE_CHANGE message format missing delimiting spaceRichard Guy Briggs2014-10-301-1/+1
|/ | | | | | | | Add a space between subj= and feature= fields to make them parsable. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paul Moore <pmoore@redhat.com>
* audit: rename audit_log_remove_rule to disambiguate for treesRichard Guy Briggs2014-10-101-2/+2
| | | | | | | | Rename audit_log_remove_rule() to audit_tree_log_remove_rule() to avoid confusion with watch and mark rule removal/changes. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* audit: cull redundancy in audit_rule_changeRichard Guy Briggs2014-10-101-11/+7
| | | | | | | | Re-factor audit_rule_change() to reduce the amount of code redundancy and simplify the logic. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* audit: WARN if audit_rule_change called illegallyEric Paris2014-10-101-1/+2
| | | | Signed-off-by: Eric Paris <eparis@redhat.com>
* audit: put rule existence check in canonical orderRichard Guy Briggs2014-10-101-1/+1
| | | | | | | | Use same rule existence check order as audit_make_tree(), audit_to_watch(), update_lsm_rule() for legibility. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* audit: get comm using lock to avoid race in string printingRichard Guy Briggs2014-09-232-4/+4
| | | | | | | | | | | | | | When task->comm is passed directly to audit_log_untrustedstring() without getting a copy or using the task_lock, there is a race that could happen that would output a NULL (\0) in the output string that would effectively truncate the rest of the report text after the comm= field in the audit, losing fields. Use get_task_comm() to get a copy while acquiring the task_lock to prevent this and to prevent the result from being a mixture of old and new values of comm. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: remove open_arg() function that is never usedRichard Guy Briggs2014-09-231-8/+0
| | | | | | | open_arg() was added in commit 55669bfa "audit: AUDIT_PERM support" and never used. Remove it. Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: correct AUDIT_GET_FEATURE return message typeRichard Guy Briggs2014-09-231-1/+1
| | | | | | | | | | | | When an AUDIT_GET_FEATURE message is sent from userspace to the kernel, it should reply with a message tagged as an AUDIT_GET_FEATURE type with a struct audit_feature. The current reply is a message tagged as an AUDIT_GET type with a struct audit_feature. This appears to have been a cut-and-paste-eo in commit b0fed40. Reported-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: set nlmsg_len for multicast messages.Richard Guy Briggs2014-09-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | Report: Looking at your example code in http://people.redhat.com/rbriggs/audit-multicast-listen/audit-multicast-listen.c, it seems that nlmsg_len field in the received messages is supposed to contain the length of the header + payload, but it is always set to the size of the header only, i.e. 16. The example program works, because the printf format specifies the minimum width, not "precision", so it simply prints out the payload until the first zero byte. This isn't too much of a problem, but precludes the use of recvmmsg, iiuc? (gdb) p *(struct nlmsghdr*)nlh $14 = {nlmsg_len = 16, nlmsg_type = 1100, nlmsg_flags = 0, nlmsg_seq = 0, nlmsg_pid = 9910} The only time nlmsg_len would have been updated was at audit_buffer_alloc() inside audit_log_start() and never updated after. It should arguably be done in audit_log_vformat(), but would be more efficient in audit_log_end(). Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: use union for audit_field values since they are mutually exclusiveRichard Guy Briggs2014-09-231-9/+20
| | | | | | | Since only one of val, uid, gid and lsm* are used at any given time, combine them to reduce the size of the struct audit_field. Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: invalid op= values for rulesBurn Alting2014-09-233-5/+5
| | | | | | | | | | | | | | | | | | Various audit events dealing with adding, removing and updating rules result in invalid values set for the op keys which result in embedded spaces in op= values. The invalid values are op="add rule" set in kernel/auditfilter.c op="remove rule" set in kernel/auditfilter.c op="remove rule" set in kernel/audit_tree.c op="updated rules" set in kernel/audit_watch.c op="remove rule" set in kernel/audit_watch.c Replace the space in the above values with an underscore character ('_'). Coded-by: Burn Alting <burn@swtf.dyndns.org> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: use atomic_t to simplify audit_serial()Richard Guy Briggs2014-09-231-12/+2
| | | | | | | Since there is already a primitive to do this operation in the atomic_t, use it to simplify audit_serial(). Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]Fabian Frederick2014-09-231-1/+1
| | | | | | | | | Use kernel.h definition. Cc: Eric Paris <eparis@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: reduce scope of audit_log_fcapsRichard Guy Briggs2014-09-232-2/+1
| | | | | | audit_log_fcaps() isn't used outside kernel/audit.c. Reduce its scope. Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: reduce scope of audit_net_idRichard Guy Briggs2014-09-231-1/+1
| | | | | | audit_net_id isn't used outside kernel/audit.c. Reduce its scope. Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
* audit: x86: drop arch from __audit_syscall_entry() interfaceRichard Guy Briggs2014-09-231-4/+2
| | | | | | | | | | | | | | | | | | | | | | Since the arch is found locally in __audit_syscall_entry(), there is no need to pass it in as a parameter. Delete it from the parameter list. x86* was the only arch to call __audit_syscall_entry() directly and did so from assembly code. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-audit@redhat.com Signed-off-by: Eric Paris <eparis@redhat.com> --- As this patch relies on changes in the audit tree, I think it appropriate to send it through my tree rather than the x86 tree.
* audit: add arch field to seccomp event logRichard Guy Briggs2014-09-231-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | The AUDIT_SECCOMP record looks something like this: type=SECCOMP msg=audit(1373478171.953:32775): auid=4325 uid=4325 gid=4325 ses=1 subj=unconfined_u:unconfined_r:unconfined_t:s0 pid=12381 comm="test" sig=31 syscall=231 compat=0 ip=0x39ea8bca89 code=0x0 In order to determine what syscall 231 maps to, we need to have the arch= field right before it. To see the event, compile this test.c program: ===== int main(void) { return seccomp_load(seccomp_init(SCMP_ACT_KILL)); } ===== gcc -g test.c -o test -lseccomp After running the program, find the record by: ausearch --start recent -m SECCOMP -i Signed-off-by: Richard Guy Briggs <rgb@redhat.com> signed-off-by: Eric Paris <eparis@redhat.com>
* audit: __audit_syscall_entry: ignore arch arg and call syscall_get_arch() ↵Richard Guy Briggs2014-09-231-1/+1
| | | | | | | | | | | | | directly Since every arch should have syscall_get_arch() defined, stop using the function argument and just collect this ourselves. We do not drop the argument as fixing some code paths (in assembly) to not pass this first argument is non-trivial. The argument will be dropped when that is fixed. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2014-08-032-5/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two fixes in the timer area: - a long-standing lock inversion due to a printk - suspend-related hrtimer corruption in sched_clock" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timer: Fix lock inversion between hrtimer_bases.lock and scheduler locks sched_clock: Avoid corrupting hrtimer tree during suspend
| * timer: Fix lock inversion between hrtimer_bases.lock and scheduler locksJan Kara2014-08-011-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clockevents_increase_min_delta() calls printk() from under hrtimer_bases.lock. That causes lock inversion on scheduler locks because printk() can call into the scheduler. Lockdep puts it as: ====================================================== [ INFO: possible circular locking dependency detected ] 3.15.0-rc8-06195-g939f04b #2 Not tainted ------------------------------------------------------- trinity-main/74 is trying to acquire lock: (&port_lock_key){-.....}, at: [<811c60be>] serial8250_console_write+0x8c/0x10c but task is already holding lock: (hrtimer_bases.lock){-.-...}, at: [<8103caeb>] hrtimer_try_to_cancel+0x13/0x66 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (hrtimer_bases.lock){-.-...}: [<8104a942>] lock_acquire+0x92/0x101 [<8142f11d>] _raw_spin_lock_irqsave+0x2e/0x3e [<8103c918>] __hrtimer_start_range_ns+0x1c/0x197 [<8107ec20>] perf_swevent_start_hrtimer.part.41+0x7a/0x85 [<81080792>] task_clock_event_start+0x3a/0x3f [<810807a4>] task_clock_event_add+0xd/0x14 [<8108259a>] event_sched_in+0xb6/0x17a [<810826a2>] group_sched_in+0x44/0x122 [<81082885>] ctx_sched_in.isra.67+0x105/0x11f [<810828e6>] perf_event_sched_in.isra.70+0x47/0x4b [<81082bf6>] __perf_install_in_context+0x8b/0xa3 [<8107eb8e>] remote_function+0x12/0x2a [<8105f5af>] smp_call_function_single+0x2d/0x53 [<8107e17d>] task_function_call+0x30/0x36 [<8107fb82>] perf_install_in_context+0x87/0xbb [<810852c9>] SYSC_perf_event_open+0x5c6/0x701 [<810856f9>] SyS_perf_event_open+0x17/0x19 [<8142f8ee>] syscall_call+0x7/0xb -> #4 (&ctx->lock){......}: [<8104a942>] lock_acquire+0x92/0x101 [<8142f04c>] _raw_spin_lock+0x21/0x30 [<81081df3>] __perf_event_task_sched_out+0x1dc/0x34f [<8142cacc>] __schedule+0x4c6/0x4cb [<8142cae0>] schedule+0xf/0x11 [<8142f9a6>] work_resched+0x5/0x30 -> #3 (&rq->lock){-.-.-.}: [<8104a942>] lock_acquire+0x92/0x101 [<8142f04c>] _raw_spin_lock+0x21/0x30 [<81040873>] __task_rq_lock+0x33/0x3a [<8104184c>] wake_up_new_task+0x25/0xc2 [<8102474b>] do_fork+0x15c/0x2a0 [<810248a9>] kernel_thread+0x1a/0x1f [<814232a2>] rest_init+0x1a/0x10e [<817af949>] start_kernel+0x303/0x308 [<817af2ab>] i386_start_kernel+0x79/0x7d -> #2 (&p->pi_lock){-.-...}: [<8104a942>] lock_acquire+0x92/0x101 [<8142f11d>] _raw_spin_lock_irqsave+0x2e/0x3e [<810413dd>] try_to_wake_up+0x1d/0xd6 [<810414cd>] default_wake_function+0xb/0xd [<810461f3>] __wake_up_common+0x39/0x59 [<81046346>] __wake_up+0x29/0x3b [<811b8733>] tty_wakeup+0x49/0x51 [<811c3568>] uart_write_wakeup+0x17/0x19 [<811c5dc1>] serial8250_tx_chars+0xbc/0xfb [<811c5f28>] serial8250_handle_irq+0x54/0x6a [<811c5f57>] serial8250_default_handle_irq+0x19/0x1c [<811c56d8>] serial8250_interrupt+0x38/0x9e [<810510e7>] handle_irq_event_percpu+0x5f/0x1e2 [<81051296>] handle_irq_event+0x2c/0x43 [<81052cee>] handle_level_irq+0x57/0x80 [<81002a72>] handle_irq+0x46/0x5c [<810027df>] do_IRQ+0x32/0x89 [<8143036e>] common_interrupt+0x2e/0x33 [<8142f23c>] _raw_spin_unlock_irqrestore+0x3f/0x49 [<811c25a4>] uart_start+0x2d/0x32 [<811c2c04>] uart_write+0xc7/0xd6 [<811bc6f6>] n_tty_write+0xb8/0x35e [<811b9beb>] tty_write+0x163/0x1e4 [<811b9cd9>] redirected_tty_write+0x6d/0x75 [<810b6ed6>] vfs_write+0x75/0xb0 [<810b7265>] SyS_write+0x44/0x77 [<8142f8ee>] syscall_call+0x7/0xb -> #1 (&tty->write_wait){-.....}: [<8104a942>] lock_acquire+0x92/0x101 [<8142f11d>] _raw_spin_lock_irqsave+0x2e/0x3e [<81046332>] __wake_up+0x15/0x3b [<811b8733>] tty_wakeup+0x49/0x51 [<811c3568>] uart_write_wakeup+0x17/0x19 [<811c5dc1>] serial8250_tx_chars+0xbc/0xfb [<811c5f28>] serial8250_handle_irq+0x54/0x6a [<811c5f57>] serial8250_default_handle_irq+0x19/0x1c [<811c56d8>] serial8250_interrupt+0x38/0x9e [<810510e7>] handle_irq_event_percpu+0x5f/0x1e2 [<81051296>] handle_irq_event+0x2c/0x43 [<81052cee>] handle_level_irq+0x57/0x80 [<81002a72>] handle_irq+0x46/0x5c [<810027df>] do_IRQ+0x32/0x89 [<8143036e>] common_interrupt+0x2e/0x33 [<8142f23c>] _raw_spin_unlock_irqrestore+0x3f/0x49 [<811c25a4>] uart_start+0x2d/0x32 [<811c2c04>] uart_write+0xc7/0xd6 [<811bc6f6>] n_tty_write+0xb8/0x35e [<811b9beb>] tty_write+0x163/0x1e4 [<811b9cd9>] redirected_tty_write+0x6d/0x75 [<810b6ed6>] vfs_write+0x75/0xb0 [<810b7265>] SyS_write+0x44/0x77 [<8142f8ee>] syscall_call+0x7/0xb -> #0 (&port_lock_key){-.....}: [<8104a62d>] __lock_acquire+0x9ea/0xc6d [<8104a942>] lock_acquire+0x92/0x101 [<8142f11d>] _raw_spin_lock_irqsave+0x2e/0x3e [<811c60be>] serial8250_console_write+0x8c/0x10c [<8104e402>] call_console_drivers.constprop.31+0x87/0x118 [<8104f5d5>] console_unlock+0x1d7/0x398 [<8104fb70>] vprintk_emit+0x3da/0x3e4 [<81425f76>] printk+0x17/0x19 [<8105bfa0>] clockevents_program_min_delta+0x104/0x116 [<8105c548>] clockevents_program_event+0xe7/0xf3 [<8105cc1c>] tick_program_event+0x1e/0x23 [<8103c43c>] hrtimer_force_reprogram+0x88/0x8f [<8103c49e>] __remove_hrtimer+0x5b/0x79 [<8103cb21>] hrtimer_try_to_cancel+0x49/0x66 [<8103cb4b>] hrtimer_cancel+0xd/0x18 [<8107f102>] perf_swevent_cancel_hrtimer.part.60+0x2b/0x30 [<81080705>] task_clock_event_stop+0x20/0x64 [<81080756>] task_clock_event_del+0xd/0xf [<81081350>] event_sched_out+0xab/0x11e [<810813e0>] group_sched_out+0x1d/0x66 [<81081682>] ctx_sched_out+0xaf/0xbf [<81081e04>] __perf_event_task_sched_out+0x1ed/0x34f [<8142cacc>] __schedule+0x4c6/0x4cb [<8142cae0>] schedule+0xf/0x11 [<8142f9a6>] work_resched+0x5/0x30 other info that might help us debug this: Chain exists of: &port_lock_key --> &ctx->lock --> hrtimer_bases.lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(hrtimer_bases.lock); lock(&ctx->lock); lock(hrtimer_bases.lock); lock(&port_lock_key); *** DEADLOCK *** 4 locks held by trinity-main/74: #0: (&rq->lock){-.-.-.}, at: [<8142c6f3>] __schedule+0xed/0x4cb #1: (&ctx->lock){......}, at: [<81081df3>] __perf_event_task_sched_out+0x1dc/0x34f #2: (hrtimer_bases.lock){-.-...}, at: [<8103caeb>] hrtimer_try_to_cancel+0x13/0x66 #3: (console_lock){+.+...}, at: [<8104fb5d>] vprintk_emit+0x3c7/0x3e4 stack backtrace: CPU: 0 PID: 74 Comm: trinity-main Not tainted 3.15.0-rc8-06195-g939f04b #2 00000000 81c3a310 8b995c14 81426f69 8b995c44 81425a99 8161f671 8161f570 8161f538 8161f559 8161f538 8b995c78 8b142bb0 00000004 8b142fdc 8b142bb0 8b995ca8 8104a62d 8b142fac 000016f2 81c3a310 00000001 00000001 00000003 Call Trace: [<81426f69>] dump_stack+0x16/0x18 [<81425a99>] print_circular_bug+0x18f/0x19c [<8104a62d>] __lock_acquire+0x9ea/0xc6d [<8104a942>] lock_acquire+0x92/0x101 [<811c60be>] ? serial8250_console_write+0x8c/0x10c [<811c6032>] ? wait_for_xmitr+0x76/0x76 [<8142f11d>] _raw_spin_lock_irqsave+0x2e/0x3e [<811c60be>] ? serial8250_console_write+0x8c/0x10c [<811c60be>] serial8250_console_write+0x8c/0x10c [<8104af87>] ? lock_release+0x191/0x223 [<811c6032>] ? wait_for_xmitr+0x76/0x76 [<8104e402>] call_console_drivers.constprop.31+0x87/0x118 [<8104f5d5>] console_unlock+0x1d7/0x398 [<8104fb70>] vprintk_emit+0x3da/0x3e4 [<81425f76>] printk+0x17/0x19 [<8105bfa0>] clockevents_program_min_delta+0x104/0x116 [<8105cc1c>] tick_program_event+0x1e/0x23 [<8103c43c>] hrtimer_force_reprogram+0x88/0x8f [<8103c49e>] __remove_hrtimer+0x5b/0x79 [<8103cb21>] hrtimer_try_to_cancel+0x49/0x66 [<8103cb4b>] hrtimer_cancel+0xd/0x18 [<8107f102>] perf_swevent_cancel_hrtimer.part.60+0x2b/0x30 [<81080705>] task_clock_event_stop+0x20/0x64 [<81080756>] task_clock_event_del+0xd/0xf [<81081350>] event_sched_out+0xab/0x11e [<810813e0>] group_sched_out+0x1d/0x66 [<81081682>] ctx_sched_out+0xaf/0xbf [<81081e04>] __perf_event_task_sched_out+0x1ed/0x34f [<8104416d>] ? __dequeue_entity+0x23/0x27 [<81044505>] ? pick_next_task_fair+0xb1/0x120 [<8142cacc>] __schedule+0x4c6/0x4cb [<81047574>] ? trace_hardirqs_off_caller+0xd7/0x108 [<810475b0>] ? trace_hardirqs_off+0xb/0xd [<81056346>] ? rcu_irq_exit+0x64/0x77 Fix the problem by using printk_deferred() which does not call into the scheduler. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched_clock: Avoid corrupting hrtimer tree during suspendStephen Boyd2014-07-241-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During suspend we call sched_clock_poll() to update the epoch and accumulated time and reprogram the sched_clock_timer to fire before the next wrap-around time. Unfortunately, sched_clock_poll() doesn't restart the timer, instead it relies on the hrtimer layer to do that and during suspend we aren't calling that function from the hrtimer layer. Instead, we're reprogramming the expires time while the hrtimer is enqueued, which can cause the hrtimer tree to be corrupted. Furthermore, we restart the timer during suspend but we update the epoch during resume which seems counter-intuitive. Let's fix this by saving the accumulated state and canceling the timer during suspend. On resume we can update the epoch and restart the timer similar to what we would do if we were starting the clock for the first time. Fixes: a08ca5d1089d "sched_clock: Use an hrtimer instead of timer" Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/1406174630-23458-1-git-send-email-john.stultz@linaro.org Cc: Ingo Molnar <mingo@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | kexec: fix build error when hugetlbfs is disabledDavid Rientjes2014-07-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | free_huge_page() is undefined without CONFIG_HUGETLBFS and there's no need to filter PageHuge() page is such a configuration either, so avoid exporting the symbol to fix a build error: In file included from kernel/kexec.c:14:0: kernel/kexec.c: In function 'crash_save_vmcoreinfo_init': kernel/kexec.c:1623:20: error: 'free_huge_page' undeclared (first use in this function) VMCOREINFO_SYMBOL(free_huge_page); ^ Introduced by commit 8f1d26d0e59b ("kexec: export free_huge_page to VMCOREINFO") Reported-by: kbuild test robot <fengguang.wu@intel.com> Acked-by: Olof Johansson <olof@lixom.net> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Josh has movedJosh Triplett2014-07-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | My IBM email addresses haven't worked for years; also map some old-but-functional forwarding addresses to my canonical address. Update my GPG key fingerprint; I moved to 4096R a long time ago. Update description. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | kexec: export free_huge_page to VMCOREINFOAtsushi Kumagai2014-07-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PG_head_mask was added into VMCOREINFO to filter huge pages in b3acc56bfe1 ("kexec: save PG_head_mask in VMCOREINFO"), but makedumpfile still need another symbol to filter *hugetlbfs* pages. If a user hope to filter user pages, makedumpfile tries to exclude them by checking the condition whether the page is anonymous, but hugetlbfs pages aren't anonymous while they also be user pages. We know it's possible to detect them in the same way as PageHuge(), so we need the start address of free_huge_page(): int PageHuge(struct page *page) { if (!PageCompound(page)) return 0; page = compound_head(page); return get_compound_page_dtor(page) == free_huge_page; } For that reason, this patch changes free_huge_page() into public to export it to VMCOREINFO. Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Acked-by: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2014-07-272-7/+39
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A bunch of fixes for perf and kprobes: - revert a commit that caused a perf group regression - silence dmesg spam - fix kprobe probing errors on ia64 and ppc64 - filter kprobe faults from userspace - lockdep fix for perf exit path - prevent perf #GP in KVM guest - correct perf event and filters" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64 kprobes/x86: Don't try to resolve kprobe faults from userspace perf/x86/intel: Avoid spamming kernel log for BTS buffer failure perf/x86/intel: Protect LBR and extra_regs against KVM lying perf: Fix lockdep warning on process exit perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappings perf/x86/intel: Use proper dTLB-load-misses event on IvyBridge perf: Revert ("perf: Always destroy groups on exit")
| * kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64Masami Hiramatsu2014-07-181-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On ia64 and ppc64, function pointers do not point to the entry address of the function, but to the address of a function descriptor (which contains the entry address and misc data). Since the kprobes code passes the function pointer stored by NOKPROBE_SYMBOL() to kallsyms_lookup_size_offset() for initalizing its blacklist, it fails and reports many errors, such as: Failed to find blacklist 0001013168300000 Failed to find blacklist 0001013000f0a000 [...] To fix this bug, use arch_deref_entry_point() to get the function entry address for kallsyms_lookup_size_offset() instead of the raw function pointer. Suzuki also pointed out that blacklist entries should also be updated as well. Reported-by: Tony Luck <tony.luck@gmail.com> Fixed-by: Suzuki K. Poulose <suzuki@in.ibm.com> Tested-by: Tony Luck <tony.luck@intel.com> Tested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (for powerpc) Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: sparse@chrisli.org Cc: Paul Mackerras <paulus@samba.org> Cc: akataria@vmware.com Cc: anil.s.keshavamurthy@intel.com Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Chris Wright <chrisw@sous-sol.org> Cc: yrl.pp-manager.tt@hitachi.com Cc: Kevin Hao <haokexin@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: rdunlap@infradead.org Cc: dl9pf@gmx.de Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: David S. Miller <davem@davemloft.net> Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20140717114411.13401.2632.stgit@kbuild-fedora.novalocal Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf: Fix lockdep warning on process exitPeter Zijlstra2014-07-161-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sasha Levin reported: > While fuzzing with trinity inside a KVM tools guest running the latest -next > kernel I've stumbled on the following spew: > > ====================================================== > [ INFO: possible circular locking dependency detected ] > 3.15.0-next-20140613-sasha-00026-g6dd125d-dirty #654 Not tainted > ------------------------------------------------------- > trinity-c578/9725 is trying to acquire lock: > (&(&pool->lock)->rlock){-.-...}, at: __queue_work (kernel/workqueue.c:1346) > > but task is already holding lock: > (&ctx->lock){-.....}, at: perf_event_exit_task (kernel/events/core.c:7471 kernel/events/core.c:7533) > > which lock already depends on the new lock. > 1 lock held by trinity-c578/9725: > #0: (&ctx->lock){-.....}, at: perf_event_exit_task (kernel/events/core.c:7471 kernel/events/core.c:7533) > > Call Trace: > dump_stack (lib/dump_stack.c:52) > print_circular_bug (kernel/locking/lockdep.c:1216) > __lock_acquire (kernel/locking/lockdep.c:1840 kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131 kernel/locking/lockdep.c:3182) > lock_acquire (./arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) > _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) > __queue_work (kernel/workqueue.c:1346) > queue_work_on (kernel/workqueue.c:1424) > free_object (lib/debugobjects.c:209) > __debug_check_no_obj_freed (lib/debugobjects.c:715) > debug_check_no_obj_freed (lib/debugobjects.c:727) > kmem_cache_free (mm/slub.c:2683 mm/slub.c:2711) > free_task (kernel/fork.c:221) > __put_task_struct (kernel/fork.c:250) > put_ctx (include/linux/sched.h:1855 kernel/events/core.c:898) > perf_event_exit_task (kernel/events/core.c:907 kernel/events/core.c:7478 kernel/events/core.c:7533) > do_exit (kernel/exit.c:766) > do_group_exit (kernel/exit.c:884) > get_signal_to_deliver (kernel/signal.c:2347) > do_signal (arch/x86/kernel/signal.c:698) > do_notify_resume (arch/x86/kernel/signal.c:751) > int_signal (arch/x86/kernel/entry_64.S:600) Urgh.. so the only way I can make that happen is through: perf_event_exit_task_context() raw_spin_lock(&child_ctx->lock); unclone_ctx(child_ctx) put_ctx(ctx->parent_ctx); raw_spin_unlock_irqrestore(&child_ctx->lock); And we can avoid this by doing the change below. I can't immediately see how this changed recently, but given that you say it's easy to reproduce, lets fix this. Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Dave Jones <davej@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140623141242.GB19860@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf: Revert ("perf: Always destroy groups on exit")Peter Zijlstra2014-07-161-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Vince reported that commit 15a2d4de0eab5 ("perf: Always destroy groups on exit") causes a regression with grouped events. In particular his read_group_attached.c test fails. https://github.com/deater/perf_event_tests/blob/master/tests/bugs/read_group_attached.c Because of the context switch optimization in perf_event_context_sched_out() the 'original' event may end up in the child process and when that exits the change in the patch in question destroys the actual grouping. Therefore revert that change and only destroy inherited groups. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-zedy3uktcp753q8fw8dagx7a@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | tracing: Fix wraparound problems in "uptime" trace clockTony Luck2014-07-212-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The "uptime" trace clock added in: commit 8aacf017b065a805d27467843490c976835eb4a5 tracing: Add "uptime" trace clock that uses jiffies has wraparound problems when the system has been up more than 1 hour 11 minutes and 34 seconds. It converts jiffies to nanoseconds using: (u64)jiffies_to_usecs(jiffy) * 1000ULL but since jiffies_to_usecs() only returns a 32-bit value, it truncates at 2^32 microseconds. An additional problem on 32-bit systems is that the argument is "unsigned long", so fixing the return value only helps until 2^32 jiffies (49.7 days on a HZ=1000 system). Avoid these problems by using jiffies_64 as our basis, and not converting to nanoseconds (we do convert to clock_t because user facing API must not be dependent on internal kernel HZ values). Link: http://lkml.kernel.org/p/99d63c5bfe9b320a3b428d773825a37095bf6a51.1405708254.git.tony.luck@intel.com Cc: stable@vger.kernel.org # 3.10+ Fixes: 8aacf017b065 "tracing: Add "uptime" trace clock that uses jiffies" Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2014-07-197-45/+85
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "The locking department delivers: - A rather large and intrusive bundle of fixes to address serious performance regressions introduced by the new rwsem / mcs technology. Simpler solutions have been discussed, but they would have been ugly bandaids with more risk than doing the right thing. - Make the rwsem spin on owner technology opt-in for architectures and enable it only on the known to work ones. - A few fixes to the lockdep userspace library" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNER locking/mutex: Disable optimistic spinning on some architectures locking/rwsem: Reduce the size of struct rw_semaphore locking/rwsem: Rename 'activity' to 'count' locking/spinlocks/mcs: Micro-optimize osq_unlock() locking/spinlocks/mcs: Introduce and use init macro and function for osq locks locking/spinlocks/mcs: Convert osq lock to atomic_t to reduce overhead locking/spinlocks/mcs: Rename optimistic_spin_queue() to optimistic_spin_node() locking/rwsem: Allow conservative optimistic spinning when readers have lock tools/liblockdep: Account for bitfield changes in lockdeps lock_acquire tools/liblockdep: Remove debug print left over from development tools/liblockdep: Fix comparison of a boolean value with a value of 2
| * | locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNERDavidlohr Bueso2014-07-163-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Just like with mutexes (CONFIG_MUTEX_SPIN_ON_OWNER), encapsulate the dependencies for rwsem optimistic spinning. No logical changes here as it continues to depend on both SMP and the XADD algorithm variant. Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Acked-by: Jason Low <jason.low2@hp.com> [ Also make it depend on ARCH_SUPPORTS_ATOMIC_RMW. ] Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1405112406-13052-2-git-send-email-davidlohr@hp.com Cc: aswin@hp.com Cc: Chris Mason <clm@fb.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Josef Bacik <jbacik@fusionio.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Waiman Long <Waiman.Long@hp.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/mutex: Disable optimistic spinning on some architecturesPeter Zijlstra2014-07-161-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The optimistic spin code assumes regular stores and cmpxchg() play nice; this is found to not be true for at least: parisc, sparc32, tile32, metag-lock1, arc-!llsc and hexagon. There is further wreckage, but this in particular seemed easy to trigger, so blacklist this. Opt in for known good archs. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Reported-by: Mikulas Patocka <mpatocka@redhat.com> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Jason Low <jason.low2@hp.com> Cc: Waiman Long <waiman.long@hp.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: John David Anglin <dave.anglin@bell.net> Cc: James Hogan <james.hogan@imgtec.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: stable@vger.kernel.org Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/20140606175316.GV13930@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/rwsem: Rename 'activity' to 'count'Peter Zijlstra2014-07-161-14/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two definitions of struct rw_semaphore, one in linux/rwsem.h and one in linux/rwsem-spinlock.h. For some reason they have different names for the initial field. This makes it impossible to use C99 named initialization for __RWSEM_INITIALIZER() -- or we have to duplicate that entire thing along with the structure definitions. The simpler patch is renaming the rwsem-spinlock variant to match the regular rwsem. This allows us to switch to C99 named initialization. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-bmrZolsbGmautmzrerog27io@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/spinlocks/mcs: Micro-optimize osq_unlock()Jason Low2014-07-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the unlock function of the cancellable MCS spinlock, the first thing we do is to retrive the current CPU's osq node. However, due to the changes made in the previous patch, in the common case where the lock is not contended, we wouldn't need to access the current CPU's osq node anymore. This patch optimizes this by only retriving this CPU's osq node after we attempt the initial cmpxchg to unlock the osq and found that its contended. Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Scott Norton <scott.norton@hp.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Aswin Chandramouleeswaran <aswin@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1405358872-3732-5-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/spinlocks/mcs: Introduce and use init macro and function for osq locksJason Low2014-07-162-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we initialize the osq lock by directly setting the lock's values. It would be preferable if we use an init macro to do the initialization like we do with other locks. This patch introduces and uses a macro and function for initializing the osq lock. Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Scott Norton <scott.norton@hp.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Aswin Chandramouleeswaran <aswin@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fusionio.com> Link: http://lkml.kernel.org/r/1405358872-3732-4-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/spinlocks/mcs: Convert osq lock to atomic_t to reduce overheadJason Low2014-07-164-11/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The cancellable MCS spinlock is currently used to queue threads that are doing optimistic spinning. It uses per-cpu nodes, where a thread obtaining the lock would access and queue the local node corresponding to the CPU that it's running on. Currently, the cancellable MCS lock is implemented by using pointers to these nodes. In this patch, instead of operating on pointers to the per-cpu nodes, we store the CPU numbers in which the per-cpu nodes correspond to in atomic_t. A similar concept is used with the qspinlock. By operating on the CPU # of the nodes using atomic_t instead of pointers to those nodes, this can reduce the overhead of the cancellable MCS spinlock by 32 bits (on 64 bit systems). Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Scott Norton <scott.norton@hp.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Aswin Chandramouleeswaran <aswin@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Chris Mason <clm@fb.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Josef Bacik <jbacik@fusionio.com> Link: http://lkml.kernel.org/r/1405358872-3732-3-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/spinlocks/mcs: Rename optimistic_spin_queue() to optimistic_spin_node()Jason Low2014-07-162-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the per-cpu nodes structure for the cancellable MCS spinlock is named "optimistic_spin_queue". However, in a follow up patch in the series we will be introducing a new structure that serves as the new "handle" for the lock. It would make more sense if that structure is named "optimistic_spin_queue". Additionally, since the current use of the "optimistic_spin_queue" structure are "nodes", it might be better if we rename them to "node" anyway. This preparatory patch renames all current "optimistic_spin_queue" to "optimistic_spin_node". Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Scott Norton <scott.norton@hp.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Aswin Chandramouleeswaran <aswin@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Chris Mason <clm@fb.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Josef Bacik <jbacik@fusionio.com> Link: http://lkml.kernel.org/r/1405358872-3732-2-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/rwsem: Allow conservative optimistic spinning when readers have lockJason Low2014-07-161-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4fc828e24cd9 ("locking/rwsem: Support optimistic spinning") introduced a major performance regression for workloads such as xfs_repair which mix read and write locking of the mmap_sem across many threads. The result was xfs_repair ran 5x slower on 3.16-rc2 than on 3.15 and using 20x more system CPU time. Perf profiles indicate in some workloads that significant time can be spent spinning on !owner. This is because we don't set the lock owner when readers(s) obtain the rwsem. In this patch, we'll modify rwsem_can_spin_on_owner() such that we'll return false if there is no lock owner. The rationale is that if we just entered the slowpath, yet there is no lock owner, then there is a possibility that a reader has the lock. To be conservative, we'll avoid spinning in these situations. This patch reduced the total run time of the xfs_repair workload from about 4 minutes 24 seconds down to approximately 1 minute 26 seconds, back to close to the same performance as on 3.15. Retesting of AIM7, which were some of the workloads used to test the original optimistic spinning code, confirmed that we still get big performance gains with optimistic spinning, even with this additional regression fix. Davidlohr found that while the 'custom' workload took a performance hit of ~-14% to throughput for >300 users with this additional patch, the overall gain with optimistic spinning is still ~+45%. The 'disk' workload even improved by ~+15% at >1000 users. Tested-by: Dave Chinner <dchinner@redhat.com> Acked-by: Davidlohr Bueso <davidlohr@hp.com> Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1404532172.2572.30.camel@j-VirtualBox Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2014-07-191-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fix from Thomas Gleixner: "Prevent a possible divide by zero in the debugging code" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix possible divide by zero in avg_atom() calculation
| * | | sched: Fix possible divide by zero in avg_atom() calculationMateusz Guzik2014-07-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | proc_sched_show_task() does: if (nr_switches) do_div(avg_atom, nr_switches); nr_switches is unsigned long and do_div truncates it to 32 bits, which means it can test non-zero on e.g. x86-64 and be truncated to zero for division. Fix the problem by using div64_ul() instead. As a side effect calculations of avg_atom for big nr_switches are now correct. Signed-off-by: Mateusz Guzik <mguzik@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1402750809-31991-1-git-send-email-mguzik@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2014-07-191-2/+18
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "A single fix for a long standing issue in the alarm timer subsystem, which was noticed recently when people finally started to use alarm timers for serious work" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: alarmtimer: Fix bug where relative alarm timers were treated as absolute
| * | | | alarmtimer: Fix bug where relative alarm timers were treated as absoluteJohn Stultz2014-07-081-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sharvil noticed with the posix timer_settime interface, using the CLOCK_REALTIME_ALARM or CLOCK_BOOTTIME_ALARM clockid, if the users tried to specify a relative time timer, it would incorrectly be treated as absolute regardless of the state of the flags argument. This patch corrects this, properly checking the absolute/relative flag, as well as adds further error checking that no invalid flag bits are set. Reported-by: Sharvil Nanavati <sharvil@google.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Sharvil Nanavati <sharvil@google.com> Cc: stable <stable@vger.kernel.org> #3.0+ Link: http://lkml.kernel.org/r/1404767171-6902-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2014-07-195-56/+121
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fixes from Thomas Gleixner: "Two RCU patches: - Address a serious performance regression on open/close caused by commit ac1bea85781e ("Make cond_resched() report RCU quiescent states") - Export RCU debug functions. Not a regression, but enablement to address a serious recursion bug in the sl*b allocators in 3.17" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Reduce overhead of cond_resched() checks for RCU rcu: Export debug_init_rcu_head() and and debug_init_rcu_head()
| * \ \ \ \ Merge branch 'urgent.2014.06.23a' of ↵Ingo Molnar2014-06-255-56/+121
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent Pull RCU fixes from Paul E. McKenney: " This series includes the following: 1. Export a pair of debug-object interfaces for RCU that will allow the slab allocators to avoid a recursion bug located by Sasha Levin. Strictly speaking, this is not a regression, but it would be good to enable the fix. 2. Address a serious performance regression on an open/close micro-benchmark located by Dave Hansen. The offending commit is ac1bea85781e (Make cond_resched() report RCU quiescent states). " Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | rcu: Reduce overhead of cond_resched() checks for RCUPaul E. McKenney2014-06-235-54/+119
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ac1bea85781e (Make cond_resched() report RCU quiescent states) fixed a problem where a CPU looping in the kernel with but one runnable task would give RCU CPU stall warnings, even if the in-kernel loop contained cond_resched() calls. Unfortunately, in so doing, it introduced performance regressions in Anton Blanchard's will-it-scale "open1" test. The problem appears to be not so much the increased cond_resched() path length as an increase in the rate at which grace periods complete, which increased per-update grace-period overhead. This commit takes a different approach to fixing this bug, mainly by moving the RCU-visible quiescent state from cond_resched() to rcu_note_context_switch(), and by further reducing the check to a simple non-zero test of a single per-CPU variable. However, this approach requires that the force-quiescent-state processing send resched IPIs to the offending CPUs. These will be sent only once the grace period has reached an age specified by the boot/sysfs parameter rcutree.jiffies_till_sched_qs, or once the grace period reaches an age halfway to the point at which RCU CPU stall warnings will be emitted, whichever comes first. Reported-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@gentwo.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> [ paulmck: Made rcu_momentary_dyntick_idle() as suggested by the ktest build robot. Also fixed smp_mb() comment as noted by Oleg Nesterov. ] Merge with e552592e (Reduce overhead of cond_resched() checks for RCU) Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | * | | | | rcu: Export debug_init_rcu_head() and and debug_init_rcu_head()Paul E. McKenney2014-06-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, call_rcu() relies on implicit allocation and initialization for the debug-objects handling of RCU callbacks. If you hammer the kernel hard enough with Sasha's modified version of trinity, you can end up with the sl*b allocators recursing into themselves via this implicit call_rcu() allocation. This commit therefore exports the debug_init_rcu_head() and debug_rcu_head_free() functions, which permits the allocators to allocated and pre-initialize the debug-objects information, so that there no longer any need for call_rcu() to do that initialization, which in turn prevents the recursion into the memory allocators. Reported-by: Sasha Levin <sasha.levin@oracle.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Looks-good-to: Christoph Lameter <cl@linux.com>
* | | | | | | Merge tag 'pm+acpi-3.16-rc6' of ↵Linus Torvalds2014-07-182-2/+3
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management fixes from Rafael Wysocki: "These are a few recent regression fixes, a revert of the ACPI video commit I promised, a system resume fix related to request_firmware(), an ACPI video quirk for one more Win8-oriented BIOS, an ACPI device enumeration documentation update and a few fixes for ARM cpufreq drivers. Specifics: - Fix for a recently introduced NULL pointer dereference in the core system suspend code occuring when platforms without ACPI attempt to use the "freeze" sleep state from Zhang Rui. - Fix for a recently introduced build warning in cpufreq headers from Brian W Hart. - Fix for a 3.13 cpufreq regression related to sysem resume that triggers on some systems with multiple CPU clusters from Viresh Kumar. - Fix for a 3.4 regression in request_firmware() resulting in WARN_ON()s on some systems during system resume from Takashi Iwai. - Revert of the ACPI video commit that changed the default value of the video.brightness_switch_enabled command line argument to 0 as it has been reported to break existing setups. - ACPI device enumeration documentation update to take recent code changes into account and make the documentation match the code again from Darren Hart. - Fixes for the sa1110, imx6q, kirkwood, and cpu0 cpufreq drivers from Linus Walleij, Nicolas Del Piano, Quentin Armitage, Viresh Kumar. - New ACPI video blacklist entry for HP ProBook 4540s from Hans de Goede" * tag 'pm+acpi-3.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: make table sentinel macros unsigned to match use cpufreq: move policy kobj to policy->cpu at resume cpufreq: cpu0: OPPs can be populated at runtime cpufreq: kirkwood: Reinstate cpufreq driver for ARCH_KIRKWOOD cpufreq: imx6q: Select PM_OPP cpufreq: sa1110: set memory type for h3600 ACPI / video: Add use_native_backlight quirk for HP ProBook 4540s PM / sleep: fix freeze_ops NULL pointer dereferences PM / sleep: Fix request_firmware() error at resume Revert "ACPI / video: change acpi-video brightness_switch_enabled default to 0" ACPI / documentation: Remove reference to acpi_platform_device_ids from enumeration.txt
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