lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20170810005556.GU20323@X58A-UD3R>
Date:   Thu, 10 Aug 2017 09:55:56 +0900
From:   Byungchul Park <byungchul.park@....com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     mingo@...nel.org, tglx@...utronix.de, walken@...gle.com,
        boqun.feng@...il.com, kirill@...temov.name,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        akpm@...ux-foundation.org, willy@...radead.org, npiggin@...il.com,
        kernel-team@....com
Subject: Re: [PATCH v8 00/14] lockdep: Implement crossrelease feature

On Wed, Aug 09, 2017 at 05:50:59PM +0200, Peter Zijlstra wrote:
> 
> 
> Heh, look what it does...

It does not happen in my machine..

I tihink it happens because of "Simplify xhlock ring buffer invalidation"
patch of you.

First of all, could you reverse yours and check if it happens, too?
If not, we have to think the simplification more.

BTW, does your patch consider the possibility that a worker and irqs can
be nested? Is it no problem even in the case?

> 
> 
> 4======================================================
> 4WARNING: possible circular locking dependency detected
> 4.13.0-rc2-00317-gadc6764a3adf-dirty #797 Tainted: G        W      
> 4------------------------------------------------------
> 4startpar/582 is trying to acquire lock:
> c (c(complete)&barr->donec){+.+.}c, at: [<ffffffff8110de4d>] flush_work+0x1fd/0x2c0
> 4
> but task is already holding lock:
> c (clockc#3c){+.+.}c, at: [<ffffffff8122e866>] lru_add_drain_all_cpuslocked+0x46/0x1a0
> 4
> which lock already depends on the new lock.
> 
> 4
> the existing dependency chain (in reverse order) is:
> 
> -> #4c (clockc#3c){+.+.}c:
>        __lock_acquire+0x10a5/0x1100
>        lock_acquire+0xea/0x1f0
>        __mutex_lock+0x6c/0x960
>        mutex_lock_nested+0x1b/0x20
>        lru_add_drain_all_cpuslocked+0x46/0x1a0
>        lru_add_drain_all+0x13/0x20
>        SyS_mlockall+0xb8/0x1c0
>        entry_SYSCALL_64_fastpath+0x23/0xc2
> 
> -> #3c (ccpu_hotplug_lock.rw_semc){++++}c:
>        __lock_acquire+0x10a5/0x1100
>        lock_acquire+0xea/0x1f0
>        cpus_read_lock+0x2a/0x90
>        kmem_cache_create+0x2a/0x1d0
>        scsi_init_sense_cache+0xa0/0xc0
>        scsi_add_host_with_dma+0x67/0x360
>        isci_pci_probe+0x873/0xc90
>        local_pci_probe+0x42/0xa0
>        work_for_cpu_fn+0x14/0x20
>        process_one_work+0x273/0x6b0
>        worker_thread+0x21b/0x3f0
>        kthread+0x147/0x180
>        ret_from_fork+0x2a/0x40
> 
> -> #2c (cscsi_sense_cache_mutexc){+.+.}c:
>        __lock_acquire+0x10a5/0x1100
>        lock_acquire+0xea/0x1f0
>        __mutex_lock+0x6c/0x960
>        mutex_lock_nested+0x1b/0x20
>        scsi_init_sense_cache+0x3d/0xc0
>        scsi_add_host_with_dma+0x67/0x360
>        isci_pci_probe+0x873/0xc90
>        local_pci_probe+0x42/0xa0
>        work_for_cpu_fn+0x14/0x20
>        process_one_work+0x273/0x6b0
>        worker_thread+0x21b/0x3f0
>        kthread+0x147/0x180
>        ret_from_fork+0x2a/0x40
> 
> -> #1c (c(&wfc.work)c){+.+.}c:
>        process_one_work+0x244/0x6b0
>        worker_thread+0x21b/0x3f0
>        kthread+0x147/0x180
>        ret_from_fork+0x2a/0x40
>        0xffffffffffffffff
> 
> -> #0c (c(complete)&barr->donec){+.+.}c:
>        check_prev_add+0x3be/0x700
>        __lock_acquire+0x10a5/0x1100
>        lock_acquire+0xea/0x1f0
>        wait_for_completion+0x3b/0x130
>        flush_work+0x1fd/0x2c0
>        lru_add_drain_all_cpuslocked+0x158/0x1a0
>        lru_add_drain_all+0x13/0x20
>        SyS_mlockall+0xb8/0x1c0
>        entry_SYSCALL_64_fastpath+0x23/0xc2
> 
> other info that might help us debug this:
> 
> Chain exists of:
>   c(complete)&barr->donec --> ccpu_hotplug_lock.rw_semc --> clockc#3c
> 
>  Possible unsafe locking scenario:
> 
>        CPU0                    CPU1
>        ----                    ----
>   lock(clockc#3c);
>                                lock(ccpu_hotplug_lock.rw_semc);
>                                lock(clockc#3c);
>   lock(c(complete)&barr->donec);
> 
>  *** DEADLOCK ***
> 
> 2 locks held by startpar/582:
>  #0: c (ccpu_hotplug_lock.rw_semc){++++}c, at: [<ffffffff8122e9ce>] lru_add_drain_all+0xe/0x20
>  #1: c (clockc#3c){+.+.}c, at: [<ffffffff8122e866>] lru_add_drain_all_cpuslocked+0x46/0x1a0
> 
> stack backtrace:
> dCPU: 23 PID: 582 Comm: startpar Tainted: G        W       4.13.0-rc2-00317-gadc6764a3adf-dirty #797
> dHardware name: Intel Corporation S2600GZ/S2600GZ, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013
> dCall Trace:
> d dump_stack+0x86/0xcf
> d print_circular_bug+0x203/0x2f0
> d check_prev_add+0x3be/0x700
> d ? add_lock_to_list.isra.30+0xc0/0xc0
> d ? is_bpf_text_address+0x82/0xe0
> d ? unwind_get_return_address+0x1f/0x30
> d __lock_acquire+0x10a5/0x1100
> d ? __lock_acquire+0x10a5/0x1100
> d ? add_lock_to_list.isra.30+0xc0/0xc0
> d lock_acquire+0xea/0x1f0
> d ? flush_work+0x1fd/0x2c0
> d wait_for_completion+0x3b/0x130
> d ? flush_work+0x1fd/0x2c0
> d flush_work+0x1fd/0x2c0
> d ? flush_workqueue_prep_pwqs+0x1c0/0x1c0
> d ? trace_hardirqs_on+0xd/0x10
> d lru_add_drain_all_cpuslocked+0x158/0x1a0
> d lru_add_drain_all+0x13/0x20
> d SyS_mlockall+0xb8/0x1c0
> d entry_SYSCALL_64_fastpath+0x23/0xc2
> dRIP: 0033:0x7f818d2e54c7
> dRSP: 002b:00007fffcce83798 EFLAGS: 00000246c ORIG_RAX: 0000000000000097
> dRAX: ffffffffffffffda RBX: 0000000000000046 RCX: 00007f818d2e54c7
> dRDX: 0000000000000000 RSI: 00007fffcce83650 RDI: 0000000000000003
> dRBP: 000000000002c010 R08: 0000000000000000 R09: 0000000000000000
> dR10: 0000000000000008 R11: 0000000000000246 R12: 000000000002d000
> dR13: 000000000002c010 R14: 0000000000001000 R15: 00007f818d599b00

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ