Anybody having this problem still?

I just had this error on my dom0 kernel log, but I don't know what triggered it. And this is an HP server.

[ 7734.861807] Eeek! page_mapcount(page) went negative! (-1)
[ 7734.861872]   page pfn = ffffffffffffffff
[ 7734.861918]   page->flags = 4
[ 7734.861960]   page->count = ffffffff
[ 7734.862004]   page->mapping = 0000000000000000
[ 7734.862070]   vma->vm_ops = 0x0
[ 7734.862117]   vma->vm_file->f_op->mmap = xen_mmap_mem+0x0/0x40
[ 7734.862181] ------------[ cut here ]------------
[ 7734.862230] kernel BUG at /build/buildd/linux-2.6.24/debian/build/custom-source-xen/mm/rmap.c:631!
[ 7734.862320] invalid opcode: 0000 [1] SMP 
[ 7734.862373] CPU 2 
[ 7734.862415] Modules linked in: af_packet xt_physdev iptable_filter ip_tables x_tables deflate zlib_deflate twofish twofish_common camellia serpent blowfish des_generic cbc ecb blkcipher aes_generic aes_x86_64 xcbc sha256_generic sha1_generic crypto_null af_key nls_cp437 isofs ebtable_broute bridge ebtable_nat ebtable_filter ebtables parport_pc lp parport loop ipv6 pcspkr shpchp pci_hotplug button iTCO_wdt iTCO_vendor_support 8250_pnp 8250 serial_core evdev ext3 jbd mbcache sr_mod cdrom ata_generic usbhid hid ata_piix sg sd_mod pata_acpi ehci_hcd libata uhci_hcd usbcore tg3 mptsas mptscsih mptbase scsi_transport_sas scsi_mod raid10 raid456 async_xor async_memcpy async_tx xor raid1 raid0 multipath linear md_mod dm_mirror dm_snapshot dm_mod thermal processor fan fuse
[ 7734.863234] Pid: 9833, comm: hwinfo Not tainted 2.6.24-23-xen #1
[ 7734.863286] RIP: e030:[<ffffffff8028e98b>]  [<ffffffff8028e98b>] page_remove_rmap+0x12b/0x140
[ 7734.863380] RSP: e02b:ffff8800c37d5d88  EFLAGS: 00010292
[ 7734.863430] RAX: 0000000000000045 RBX: ffff880002c54fc8 RCX: ffffffffff5f7000
[ 7734.863487] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8058ce64
[ 7734.863543] RBP: ffff8800f205f678 R08: 0000000000000042 R09: 00000000ffffffff
[ 7734.863599] R10: 0000000000000000 R11: 0000000000000000 R12: 00007ffbac000000
[ 7734.863656] R13: 0000000000000020 R14: ffff880002c54fc8 R15: 00007ffbac033000
[ 7734.863714] FS:  00007ffbac0e06e0(0000) GS:ffffffff805c7100(0000) knlGS:0000000000000000
[ 7734.863801] CS:  e033 DS: 0000 ES: 0000
[ 7734.863846] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 7734.863903] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 7734.863959] Process hwinfo (pid: 9833, threadinfo ffff8800c37d4000, task ffff8800f2175040)
[ 7734.864046] Stack:  00000000000000c0 ffff8800bec71f98 00007ffbabff3000 ffffffff80283d87
[ 7734.864148]  ffffffff8061a420 ffff880001cf2438 00007ffbac032fff 0000000000000000
[ 7734.864246]  ffff8800c37d5eb0 00007ffbac033000 00007ffbabff3000 ffff8800f205f678
[ 7734.864312] Call Trace:
[ 7734.864393]  [<ffffffff80283d87>] unmap_vmas+0x687/0xb20
[ 7734.864485]  [<ffffffff80289d08>] unmap_region+0xc8/0x160
[ 7734.864549]  [<ffffffff8028ac2a>] do_munmap+0x22a/0x2f0
[ 7734.864607]  [<ffffffff80471862>] __down_write_nested+0x12/0x100
[ 7734.864671]  [<ffffffff8028ad3d>] sys_munmap+0x4d/0x80
[ 7734.864730]  [<ffffffff8020c698>] system_call+0x68/0x6d
[ 7734.864788]  [<ffffffff8020c630>] system_call+0x0/0x6d
[ 7734.864849] 
[ 7734.864886] 
[ 7734.864887] Code: 0f 0b eb fe 48 8b 53 10 e9 65 ff ff ff 0f 1f 84 00 00 00 00 
[ 7734.865095] RIP  [<ffffffff8028e98b>] page_remove_rmap+0x12b/0x140
[ 7734.865151]  RSP <ffff8800c37d5d88>
[ 7734.865820] ---[ end trace 7f378db783039b52 ]---