linux/arch
Peter Zijlstra e32e58a96d x86: fix lockdep warning during suspend-to-ram
Andrew Morton wrote:

> I've been seeing the below for a long time during suspend-to-ram on the Vaio.
>
>
> PM: Syncing filesystems ... done.
> PM: Preparing system for mem sleep
> Freezing user space processes ... <4>------------[ cut here ]------------
> WARNING: at kernel/lockdep.c:2658 check_flags+0x4c/0x127()
> Modules linked in: i915 drm ipw2200 sonypi ipv6 autofs4 hidp l2cap bluetooth sunrpc nf_conntrack_netbios_ns ipt_REJECT nf_conntrack_ipv4 xt_state nf_conntrack xt_tcpudp iptable_filter ip_tables x_tables acpi_cpufreq nvram ohci1394 ieee1394 ehci_hcd uhci_hcd sg joydev snd_hda_intel snd_seq_dummy sr_mod snd_seq_oss cdrom snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss ieee80211 pcspkr ieee80211_crypt snd_pcm i2c_i801 snd_timer i2c_core ide_pci_generic piix snd soundcore snd_page_alloc button ext3 jbd ide_disk ide_core [last unloaded: ipw2200]
> Pid: 3250, comm: zsh Not tainted 2.6.26-rc5 #1
>  [<c011c5f5>] warn_on_slowpath+0x41/0x6d
>  [<c01080e6>] ? native_sched_clock+0x82/0x96
>  [<c013789c>] ? mark_held_locks+0x41/0x5c
>  [<c0315688>] ? _spin_unlock_irqrestore+0x36/0x58
>  [<c0137a29>] ? trace_hardirqs_on+0xe6/0x10d
>  [<c0138637>] ? __lock_acquire+0xae3/0xb2b
>  [<c0313413>] ? schedule+0x39b/0x3b4
>  [<c0135596>] check_flags+0x4c/0x127
>  [<c01386b9>] lock_acquire+0x3a/0x86
>  [<c0315075>] _spin_lock+0x26/0x53
>  [<c0140660>] ? refrigerator+0x13/0xc3
>  [<c0140660>] refrigerator+0x13/0xc3
>  [<c012684a>] get_signal_to_deliver+0x3c/0x31e
>  [<c0102fe7>] do_notify_resume+0x91/0x6ee
>  [<c01359fd>] ? lock_release_holdtime+0x50/0x56
>  [<c0315688>] ? _spin_unlock_irqrestore+0x36/0x58
>  [<c0235d24>] ? read_chan+0x0/0x58c
>  [<c0137a29>] ? trace_hardirqs_on+0xe6/0x10d
>  [<c0315694>] ? _spin_unlock_irqrestore+0x42/0x58
>  [<c0230afa>] ? tty_ldisc_deref+0x5c/0x63
>  [<c0233104>] ? tty_read+0x66/0x98
>  [<c014b3f0>] ? audit_syscall_exit+0x2aa/0x2c5
>  [<c0109430>] ? do_syscall_trace+0x6b/0x16f
>  [<c0103a9c>] work_notifysig+0x13/0x1b
>  =======================
> ---[ end trace 25b49fe59a25afa5 ]---
> possible reason: unannotated irqs-off.
> irq event stamp: 58919
> hardirqs last  enabled at (58919): [<c0103afd>] syscall_exit_work+0x11/0x26

Joy - I so love entry.S

Best I can make of it:

syscall_exit_work
  resume_userspace
    DISABLE_INTERRUPTS
    (no TRACE_IRQS_OFF)
      work_pending
        work_notifysig
          do_notify_resume()
            do_signal()
              get_signal_to_deliver()
                try_to_freeze()
                  refrigerator()
                    task_lock() -> check_flags() -> BANG

The normal path is:

syscall_exit_work
  resume_userspace
    DISABLE_INTERRUPTS
    restore_all
      TRACE_IRQS_IRET
      iret

No idea why that would not warn..

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-12 21:27:09 +02:00
..
alpha [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
arm [ARM] pxa: fix tosa.c build error 2008-06-02 20:38:15 +01:00
avr32 avr32: Fix cpufreq oops when ondemand governor is default 2008-05-27 09:37:42 +02:00
blackfin Blackfin arch: protect only the SPI bus controller with CONFIG_SPI_BFIN 2008-06-07 15:03:01 +08:00
cris [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
frv Fix various old email addresses for dwmw2 2008-06-06 11:29:10 -07:00
h8300 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
ia64 [IA64] Workaround for RSE issue 2008-05-27 13:24:39 -07:00
m32r [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
m68k m68k: enable CONFIG_COMPAT_BRK by default 2008-06-06 11:29:09 -07:00
m68knommu [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
mips Fix divide by zero error in build_clear_page() and build_copy_page() 2008-06-05 18:13:16 +01:00
mn10300 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
parisc [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
powerpc [POWERPC] Make walk_memory_resource available with MEMORY_HOTPLUG=n 2008-06-09 11:32:41 +10:00
ppc [POWERPC] Export empty_zero_page and copy_page in arch/ppc 2008-05-31 17:08:28 +10:00
s390 [S390] Update default configuration. 2008-05-30 10:03:36 +02:00
sh sh: Add -mno-fdpic to default flags. 2008-06-09 16:49:43 +09:00
sparc sparc: switch /proc/led to seq_file 2008-06-03 15:21:21 -07:00
sparc64 sparc64: Prevent stack backtrace false positives on trap frames. 2008-05-21 21:50:01 -07:00
um uml: PATH_MAX needs limits.h 2008-06-06 11:29:10 -07:00
v850 [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
x86 x86: fix lockdep warning during suspend-to-ram 2008-06-12 21:27:09 +02:00
xtensa [PATCH] take init_files to fs/file.c 2008-05-16 17:22:20 -04:00
.gitignore
Kconfig dma: add dma_*map*_attrs() interfaces 2008-04-29 08:06:11 -07:00