>From:
tinnycloud@xxxxxxxxxxx>To:
tinnycloud@xxxxxxxxxxx>Subject: Linux Guest Crash on stress test of memory sharing
>Date: Tue, 25 Jan 2011 13:07:15 +0800
>
>Hi:
>
> Follow George's suggestion to summit the bug in this new thread.
>
> Start 24 linux HVMS on a physical host, each of them reboot through "xm reboot" every 30minutes.
> After several hours, some of the HVM will crash.
>
> All of the crash HVM are stopped during booting.
> The bug still exists even I forbid page sharing by cheating tapdisk that xc_memshr_nominate_gref()
> return failure. No bug if
memory sharing is disabled.
> (This means only mem_sharing_nominate_page() are called, and in mem_sharing_nominate_page()
> page type is set to p2m_shared, so later it needs to be unshared when someone try to use it)
>
> I remember there is a call routine in memory sharing,
> hvm_hap_nested_page_fault()->mem_sharing_unshare_page()
> compare to the crash dump, it might indicates some connections.
>
>DomU kernel is from
ftp://ftp.redhat.com/pub/redhat/linux/enterprise/5Server/en/os/SRPMS/kernel-2.6.18-164.el5.src.rpm>Xen version: 4.0.0
>
>crash dump stack :
>
>crash> bt -l
>PID: 2422
TASK: ffff810013b40860 CPU: 1 COMMAND: "setfont"
> #0 [ffff810012cef900] xen_panic_event at ffffffff88001d28
> #1 [ffff810012cef920] notifier_call_chain at ffffffff80066eaa
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/kernel/sys.c: 146
> #2 [ffff810012cef940] panic at ffffffff8009094a
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/kernel/panic.c: 101
> #3 [ffff810012cefa30] oops_end at ffffffff80064fca
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/arch/x86_64/kernel/traps.c: 539
> #4 [ffff810012cefa40] do_page_fault at ffffffff80066dc0
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/arch/x86_64/mm/fault.c: 591
> #5 [ffff810012cefb30] error_exit at ffffffff8005dde9
> [exception RIP: vgacon_do_font_op+435]
> RIP: ffffffff8005162d&n
bsp; RSP: ffff810012cefbe8 RFLAGS: 00010287
> RAX: ffff8100000a6000 RBX: ffffffff804b3740 RCX: ffff8100000a4ae0
> RDX: ffff810012d16ae1 RSI: ffff810012d14000 RDI: ffffffff803244c4
> RBP: ffff810012d14000 R8: d0d6999996000000 R9: 0000009090b0b0ff
> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
> R13: 0000000000000001 R14: 0000000000000001 R15: 000000000000000e
> ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
> #6 [ffff810012cefc20] vgacon_font_set at ffffffff8016bec5
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/drivers/video/console/vgacon.c: 1238
> #7 [ffff810012cefc60] con_font_op at ffffffff801aa86b
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_6
4/drivers/char/vt.c: 3645
> #8 [ffff810012cefcd0] vt_ioctl at ffffffff801a5af4
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/drivers/char/vt_ioctl.c: 965
> #9 [ffff810012cefd70] tty_ioctl at ffffffff80038a2c
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/drivers/char/tty_io.c: 3340
>#10 [ffff810012cefeb0] do_ioctl at ffffffff800420d9
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/fs/ioctl.c: 39
>#11 [ffff810012cefed0] vfs_ioctl at ffffffff800302ce
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/fs/ioctl.c: 500
>#12 [ffff810012ceff40] sys_ioctl at ffffffff8004c766
> /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18.x86_64/fs/ioctl.c: 520
>#13 [ffff810012ceff80] tracesys at ffffffff8005d28d (via system_call)
> RIP: 00000039294cc557 RSP: 00007fff1a57ed98
RFLAGS: 00000246
> RAX: ffffffffffffffda RBX: ffffffff8005d28d RCX: ffffffffffffffff
> RDX: 00007fff1a57edb0 RSI: 0000000000004b72 RDI: 0000000000000003
> RBP: 000000001e33dab0 R8: 0000000000000010 R9: 0000000000800000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000010
> R13: 0000000000000200 R14: 0000000000000008 R15: 0000000000000008
> ORIG_RAX: 0000000000000010 CS: 0033 SS: 002b
