hibernation hangs with ATA errors (lockup_detector bug)

[Jiri Slaby <jirislaby@gmail.com>]

Hi,

with -next I get the following errors while trying to hibernate in
qemu-kvm after the image is stored on disk:
sd 0:0:0:0: [sda] Starting disk
sd 0:0:1:0: [sdb] Starting disk
e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
ata1.00: configured for MWDMA2
ata1.01: configured for MWDMA2
PM: thaw of devices complete after 168.017 msecs
ata2.01: qc timeout (cmd 0xec)
ata2.01: failed to IDENTIFY (I/O error, err_mask=0x4)
sd 0:0:1:0: [sdb] Stopping disk
sd 0:0:0:0: [sda] Stopping disk
uhci_hcd 0000:00:01.2: PCI INT D disabled
e1000 0000:00:03.0: PCI INT A disabled
ata2.01: qc timeout (cmd 0xec)
ata2.01: failed to IDENTIFY (I/O error, err_mask=0x4)
ata2.01: qc timeout (cmd 0xec)
ata2.01: failed to IDENTIFY (I/O error, err_mask=0x4)
...

I bisected it down to:
commit 58687acba59266735adb8ccd9b5b9aa2c7cd205b
Author: Don Zickus <dzickus@redhat.com>
Date:   Fri May 7 17:11:44 2010 -0400

    lockup_detector: Combine nmi_watchdog and softlockup detector

    The new nmi_watchdog (which uses the perf event subsystem) is very
    similar in structure to the softlockup detector.  Using Ingo's
    suggestion, I combined the two functionalities into one file:
    kernel/watchdog.c.
...



The config difference against 58687acb^:
--- .config.old     2010-05-31 16:01:51.727312636 +0200
+++ .config 2010-05-31 16:11:08.682136175 +0200
@@ -1,7 +1,7 @@
 #
 # Automatically generated make config: don't edit
 # Linux kernel version: 2.6.34-rc7
-# Mon May 31 16:01:51 2010
+# Mon May 31 16:11:08 2010
 #
 CONFIG_64BIT=y
 # CONFIG_X86_32 is not set
@@ -2133,7 +2133,7 @@
 CONFIG_DEBUG_KERNEL=y
 CONFIG_DEBUG_SHIRQ=y
 CONFIG_DETECT_SOFTLOCKUP=y
-CONFIG_NMI_WATCHDOG=y
+CONFIG_LOCKUP_DETECTOR=y
 # CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC is not set
 CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE=0
 CONFIG_DETECT_HUNG_TASK=y




'nowatchdog' parameter helps.

$ grep PERF .config
CONFIG_HAVE_PERF_EVENTS=y
CONFIG_PERF_EVENTS=y
# CONFIG_PERF_COUNTERS is not set
# CONFIG_DEBUG_PERF_USE_VMALLOC is not set
CONFIG_HAVE_PERF_EVENTS_NMI=y

-- 
js