Created attachment 20846 [details]
Xorg.0.log

Forwarding this bug from a Ubuntu reporter:
https://bugs.edge.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/298768

X hangs in pixmap routines with a frequency of every few days.  Backtrace below.  A couple other similar (but less detailed) backtraces are available on the downstream bug.

01:00.0 VGA compatible controller [0300]: ATI Technologies Inc RV410 [Radeon X700 Pro (PCIE)] [1002:5e4b]
	Subsystem: Micro-Star International Co., Ltd. Device [1462:1780]


(gdb) backtrace full
#0 damageDestroyPixmap (pPixmap=0x9744840)
    at ../../../miext/damage/damage.c:1634
        pPrev = (DamagePtr *) 0x81dc968
        pDamage = (DamagePtr) 0x81dc968
        pScreen = (ScreenPtr) 0x8763cd0
        pScrPriv = (DamageScrPrivPtr) 0x876d3a8
#1 0xb7fb0fb8 in XvDestroyPixmap (pPix=0x9744840) at ../../Xext/xvmain.c:381
        status = 136169832
        pScreen = (ScreenPtr) 0x8763cd0
        pa = (XvAdaptorPtr) 0x87799ec
        na = 2
        pp = (XvPortPtr) 0x877a7f0
        np = 16
#2 0x08085ff5 in dixDestroyPixmap (value=0x9744840, pid=63207183)
    at ../../dix/dispatch.c:1272
No locals.
#3 0x0807461c in FreeResource (id=63207183, skipDeleteFuncType=0)
    at ../../dix/resource.c:561
        rtype = 2
        cid = <value optimized out>
        res = (ResourcePtr) 0x90daaa0
        prev = (ResourcePtr *) 0x9c7bb90
        head = (ResourcePtr *) 0x9c7bb90
#4 0x08087963 in ProcFreePixmap (client=0x9be5ad0)
    at ../../dix/dispatch.c:1358
        pMap = (PixmapPtr) 0x9744840
        rc = 136169832
#5 0x0808c89f in Dispatch () at ../../dix/dispatch.c:454
        result = <value optimized out>
        client = (ClientPtr) 0x9be5ad0
        nready = 0
        start_tick = 240240
#6 0x08071d1d in main (argc=10, argv=0xbfddd0e4, envp=0xc14fe8f4)
    at ../../dix/main.c:441
        i = <value optimized out>
        error = 136151028
        xauthfile = <value optimized out>
        alwaysCheckForInput = {0, 1}

[Original Report]
I've updated hardy to intrepid and experience sudden X hangs. The logs say
 [mi] EQ overflowing. The server is probably stuck in an infinite loop.
 [mi] mieqEnequeue: out-of-order valuator event; dropping.
repeatingly and dmesg tells me about usb difficulties (repeating "usb 2-2: new full speed USB device using uhci_hcd and address (looping number)" continiously).

The system becomes unresponsive to any keyboard/mouse activity and X is no longer refreshed.
Though, the system is still reachable via network.

I'm not using compiz and have not enabled 3d accelaration. I'm using the radeon driver.